/mandos/release : revision 237.7.860

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

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*

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* Everything else is

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*

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

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

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

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

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*

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

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*

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* This file is part of Mandos.

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*

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

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

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

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* (at your option) any later version.

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*

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

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* WITHOUT ANY WARRANTY; without even the implied warranty of

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

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* General Public License for more details.

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*

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

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* along with this program. If not, see

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

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

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*

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* Contact the authors at <mandos@fukt.bsnet.se>.

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

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*/

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

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#ifndef _LARGEFILE_SOURCE

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35

#define _LARGEFILE_SOURCE

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#endif

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#endif /* not _LARGEFILE_SOURCE */

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#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

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#endif

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

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

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stdout, ferror(), remove() */

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

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#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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#endif /* not _FILE_OFFSET_BITS */

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#define _GNU_SOURCE /* program_invocation_short_name,

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TEMP_FAILURE_RETRY(), O_CLOEXEC,

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scandirat(), asprintf() */

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

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

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

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

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

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sockaddr_in6, PF_INET6,

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SOCK_STREAM, uid_t, gid_t, open(),

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opendir(), DIR */

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

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

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inet_pton(), connect() */

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

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#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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#include <argp.h> /* argp_program_version,

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argp_program_bug_address,

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struct argp_option,

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struct argp_state, argp_error(),

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argp_state_help,

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ARGP_HELP_STD_HELP,

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ARGP_HELP_EXIT_ERR,

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ARGP_HELP_EXIT_OK, ARGP_HELP_USAGE,

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argp_err_exit_status,

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ARGP_ERR_UNKNOWN, struct argp,

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argp_parse(), ARGP_IN_ORDER,

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ARGP_NO_HELP */

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

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#include <sys/types.h> /* uid_t, gid_t, sig_atomic_t,

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seteuid(), setuid(), pid_t,

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setgid(), getuid(), getgid() */

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#include <unistd.h> /* uid_t, gid_t, TEMP_FAILURE_RETRY(),

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seteuid(), setuid(), close(),

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ssize_t, read(), fork(), setgid(),

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_exit(), dup2(), STDIN_FILENO,

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STDERR_FILENO, STDOUT_FILENO,

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fexecve(), write(), getuid(),

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getgid(), fchown(), symlink(),

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sleep(), unlinkat(), pause() */

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#include <netinet/in.h> /* in_port_t, struct sockaddr_in6,

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sa_family_t, struct sockaddr_in,

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htons(), IN6_IS_ADDR_LINKLOCAL,

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INET_ADDRSTRLEN, INET6_ADDRSTRLEN,

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ntohl(), IPPROTO_IP */

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#include <time.h> /* struct timespec, clock_gettime(),

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CLOCK_MONOTONIC, time_t, struct tm,

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gmtime_r(), clock_settime(),

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CLOCK_REALTIME, nanosleep() */

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#include <errno.h> /* errno,

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program_invocation_short_name,

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EINTR, EINVAL, ENETUNREACH,

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EHOSTUNREACH, ECONNREFUSED, EPROTO,

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EIO, ENOENT, ENXIO, error_t,

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ENOMEM, EISDIR, ENOTEMPTY */

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

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vfprintf(), off_t, SEEK_SET,

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stdout, fwrite(), ferror(),

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fflush(), asprintf() */

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#include <stdarg.h> /* va_list, va_start(), vfprintf() */

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#include <stdlib.h> /* realloc(), free(), malloc(),

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getenv(), EXIT_FAILURE, setenv(),

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EXIT_SUCCESS, strtof(), strtod(),

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srand(), mkdtemp(), abort() */

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

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strerror(), strncpy(), strspn(),

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memcpy(), strrchr(), strchr(),

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strsignal() */

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

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O_PATH, O_CLOEXEC, openat(),

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O_NOFOLLOW, AT_REMOVEDIR */

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

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#include <sys/stat.h> /* struct stat, fstat(), fstatat(),

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S_ISREG(), S_IXUSR, S_IXGRP,

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S_IXOTH, lstat() */

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#include <net/if.h> /* IF_NAMESIZE, if_indextoname(),

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if_nametoindex(), SIOCGIFFLAGS,

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IFF_LOOPBACK, IFF_POINTOPOINT,

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IFF_BROADCAST, IFF_NOARP, IFF_UP,

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IFF_RUNNING, SIOCSIFFLAGS */

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#include <sysexits.h> /* EX_NOPERM, EX_OSERR,

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EX_UNAVAILABLE, EX_USAGE */

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

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

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WEXITSTATUS(), WIFSIGNALED(),

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WTERMSIG() */

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#include <signal.h> /* kill(), SIGTERM, struct sigaction,

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SIG_DFL, sigemptyset(),

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sigaddset(), SIGINT, SIGHUP,

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SIG_IGN, raise() */

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#include <sys/socket.h> /* struct sockaddr_storage, AF_INET6,

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PF_INET6, AF_INET, PF_INET,

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socket(), SOCK_STREAM,

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SOCK_CLOEXEC, struct sockaddr,

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connect(), SOCK_DGRAM */

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

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argz_delete(), argz_stringify(),

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argz_add(), argz_count() */

127

#include <inttypes.h> /* PRIuMAX, uintmax_t, uint32_t,

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PRIdMAX, PRIu16, intmax_t,

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strtoimax() */

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

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

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

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

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SIOCSIFFLAGS, if_indextoname(),

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if_nametoindex(), IF_NAMESIZE */

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#include <netinet/in.h> /* IN6_IS_ADDR_LINKLOCAL,

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INET_ADDRSTRLEN, INET6_ADDRSTRLEN

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*/

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

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

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setgid(), pause() */

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

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#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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argp_parse(), ARGP_KEY_ARG,

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ARGP_KEY_END, ARGP_ERR_UNKNOWN */

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#include <signal.h> /* sigemptyset(), sigaddset(),

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sigaction(), SIGTERM, sig_atomic_t,

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raise() */

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

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EX_NOHOST, EX_IOERR, EX_PROTOCOL */

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

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

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

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EAI_SYSTEM, gai_strerror() */

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

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

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alphasort(), scandir() */

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#include <limits.h> /* INT_MAX */

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138

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139

#ifdef __linux__

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

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/* GnuTLS */

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#include <gnutls/gnutls.h> /* All GnuTLS types, constants and

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functions:

106

gnutls_*

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init_gnutls_session(),

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GNUTLS_* */

156

functions: gnutls_*, GNUTLS_* */

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#if GNUTLS_VERSION_NUMBER < 0x030600

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#include <gnutls/openpgp.h>

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/* gnutls_certificate_set_openpgp_key_file(),

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GNUTLS_OPENPGP_FMT_BASE64 */

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/* gnutls_certificate_set_openpgp_key_file(),

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GNUTLS_OPENPGP_FMT_BASE64 */

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#elif GNUTLS_VERSION_NUMBER >= 0x030606

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#include <gnutls/x509.h> /* GNUTLS_PKCS_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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168

functions:

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gpgme_*

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GPGME_PROTOCOL_OpenPGP,

118

GPG_ERR_NO_* */

169

gpgme_*, GPG_ERR_NO_*,

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GPGME_IMPORT_*

171

GPGME_PROTOCOL_OpenPGP */

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#define BUFFER_SIZE 256

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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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181

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bool debug = false;

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static const char mandos_protocol_version[] = "1";

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const char *argp_program_version = "mandos-client " VERSION;

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

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

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

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char *connect_to = NULL;

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const char *hookdir = HOOKDIR;

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int hookdir_fd = -1;

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uid_t uid = 65534;

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gid_t gid = 65534;

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

194

typedef struct server{

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const char *ip;

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in_port_t port;

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AvahiIfIndex if_index;

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int af;

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struct timespec last_seen;

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struct server *next;

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struct server *prev;

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} server;

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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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gnutls_dh_params_t dh_params;

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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;

141

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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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/* global so signal handler can reach it*/

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AvahiSimplePoll *simple_poll;

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sig_atomic_t quit_now = 0;

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int signal_received = 0;

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/* Function to use when printing errors */

224

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);

228

errno = e;

229

perror(print_text);

230

}

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

233

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

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va_list ap;

235

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));

240

}

241

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/*

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

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

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* "buffer_length" is how much is already used.

154

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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,

156

size_t buffer_capacity){

249

size_t buffer_capacity){

157

250

if(buffer_length + BUFFER_SIZE > buffer_capacity){

158

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

159

if(buffer == NULL){

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

252

if(new_buf == NULL){

253

int old_errno = errno;

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free(*buffer);

255

errno = old_errno;

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*buffer = NULL;

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return 0;

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}

259

*buffer = new_buf;

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260

buffer_capacity += BUFFER_SIZE;

163

261

}

164

262

return buffer_capacity;

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263

}

166

264

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

266

__attribute__((nonnull, warn_unused_result))

267

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

268

int af, server **current_server){

269

int ret;

270

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

271

if(new_server == NULL){

272

perror_plus("malloc");

273

return false;

274

}

275

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

276

.port = port,

277

.if_index = if_index,

278

.af = af };

279

if(new_server->ip == NULL){

280

perror_plus("strdup");

281

free(new_server);

282

return false;

283

}

284

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

285

if(ret == -1){

286

perror_plus("clock_gettime");

287

#ifdef __GNUC__

288

#pragma GCC diagnostic push

289

#pragma GCC diagnostic ignored "-Wcast-qual"

290

#endif

291

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

292

#ifdef __GNUC__

293

#pragma GCC diagnostic pop

294

#endif

295

free(new_server);

296

return false;

297

}

298

/* Special case of first server */

299

if(*current_server == NULL){

300

new_server->next = new_server;

301

new_server->prev = new_server;

302

*current_server = new_server;

303

} else {

304

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

305

new_server->next = *current_server;

306

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

307

new_server->prev->next = new_server;

308

(*current_server)->prev = new_server;

309

}

310

return true;

311

}

312

313

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

314

__attribute__((warn_unused_result))

315

int raise_privileges(void){

316

int old_errno = errno;

317

int ret = 0;

318

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

319

ret = errno;

320

}

321

errno = old_errno;

322

return ret;

323

}

324

325

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

326

__attribute__((warn_unused_result))

327

int raise_privileges_permanently(void){

328

int old_errno = errno;

329

int ret = raise_privileges();

330

if(ret != 0){

331

errno = old_errno;

332

return ret;

333

}

334

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

335

ret = errno;

336

}

337

errno = old_errno;

338

return ret;

339

}

340

341

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

342

__attribute__((warn_unused_result))

343

int lower_privileges(void){

344

int old_errno = errno;

345

int ret = 0;

346

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

347

ret = errno;

348

}

349

errno = old_errno;

350

return ret;

351

}

352

353

/* Lower privileges permanently */

354

__attribute__((warn_unused_result))

355

int lower_privileges_permanently(void){

356

int old_errno = errno;

357

int ret = 0;

358

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

359

ret = errno;

360

}

361

errno = old_errno;

362

return ret;

363

}

364

167

365

/*

168

366

* Initialize GPGME.

169

367

*/

170

static bool init_gpgme(const char *seckey,

171

const char *pubkey, const char *tempdir){

368

__attribute__((nonnull, warn_unused_result))

369

static bool init_gpgme(const char * const seckey,

370

const char * const pubkey,

371

const char * const tempdir,

372

mandos_context *mc){

172

373

gpgme_error_t rc;

173

374

gpgme_engine_info_t engine_info;

174

375

175

176

376

/*

177

377

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

178

378

*/

179

bool import_key(const char *filename){

379

bool import_key(const char * const filename){

180

380

int ret;

181

381

int fd;

182

382

gpgme_data_t pgp_data;

183

383

184

384

fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));

185

385

if(fd == -1){

186

perror("open");

386

perror_plus("open");

187

387

return false;

188

388

}

189

389

390

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

391

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

392

do {

393

{

394

time_t currtime = time(NULL);

395

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

396

struct tm tm;

397

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

398

perror_plus("gmtime_r");

399

break;

400

}

401

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

402

break;

403

}

404

if(debug){

405

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

406

}

407

} else {

408

if(debug){

409

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

410

}

411

}

412

}

413

struct stat keystat;

414

ret = fstat(fd, &keystat);

415

if(ret != 0){

416

perror_plus("fstat");

417

break;

418

}

419

ret = raise_privileges();

420

if(ret != 0){

421

errno = ret;

422

perror_plus("Failed to raise privileges");

423

break;

424

}

425

if(debug){

426

fprintf_plus(stderr,

427

"Setting system clock to key file mtime");

428

}

429

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

430

perror_plus("clock_settime");

431

}

432

ret = lower_privileges();

433

if(ret != 0){

434

errno = ret;

435

perror_plus("Failed to lower privileges");

436

}

437

} while(false);

438

190

439

rc = gpgme_data_new_from_fd(&pgp_data, fd);

191

440

if(rc != GPG_ERR_NO_ERROR){

192

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

193

gpgme_strsource(rc), gpgme_strerror(rc));

441

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

442

gpgme_strsource(rc), gpgme_strerror(rc));

194

443

return false;

195

444

}

196

445

197

rc = gpgme_op_import(mc.ctx, pgp_data);

446

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

198

447

if(rc != GPG_ERR_NO_ERROR){

199

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

200

gpgme_strsource(rc), gpgme_strerror(rc));

448

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

449

gpgme_strsource(rc), gpgme_strerror(rc));

201

450

return false;

202

451

}

452

{

453

gpgme_import_result_t import_result

454

= gpgme_op_import_result(mc->ctx);

455

if((import_result->imported < 1

456

or import_result->not_imported > 0)

457

and import_result->unchanged == 0){

458

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

459

fprintf_plus(stderr,

460

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

461

import_result->considered);

462

fprintf_plus(stderr,

463

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

464

import_result->no_user_id);

465

fprintf_plus(stderr,

466

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

467

import_result->imported);

468

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

469

import_result->imported_rsa);

470

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

471

import_result->unchanged);

472

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

473

import_result->new_user_ids);

474

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

475

import_result->new_sub_keys);

476

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

477

import_result->new_signatures);

478

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

479

import_result->new_revocations);

480

fprintf_plus(stderr,

481

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

482

import_result->secret_read);

483

fprintf_plus(stderr,

484

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

485

import_result->secret_imported);

486

fprintf_plus(stderr,

487

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

488

import_result->secret_unchanged);

489

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

490

import_result->not_imported);

491

for(gpgme_import_status_t import_status

492

= import_result->imports;

493

import_status != NULL;

494

import_status = import_status->next){

495

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

496

import_status->fpr);

497

if(import_status->result != GPG_ERR_NO_ERROR){

498

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

499

gpgme_strsource(import_status->result),

500

gpgme_strerror(import_status->result));

501

}

502

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

503

fprintf_plus(stderr,

504

import_status->status & GPGME_IMPORT_NEW

505

? "The key was new.\n"

506

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

507

fprintf_plus(stderr,

508

import_status->status & GPGME_IMPORT_UID

509

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

510

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

511

fprintf_plus(stderr,

512

import_status->status & GPGME_IMPORT_SIG

513

? "The key contained new signatures.\n"

514

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

515

fprintf_plus(stderr,

516

import_status->status & GPGME_IMPORT_SUBKEY

517

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

518

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

519

fprintf_plus(stderr,

520

import_status->status & GPGME_IMPORT_SECRET

521

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

522

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

523

}

524

return false;

525

}

526

}

203

527

204

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

528

ret = close(fd);

205

529

if(ret == -1){

206

perror("close");

530

perror_plus("close");

207

531

}

208

532

gpgme_data_release(pgp_data);

209

533

return true;

210

534

}

211

535

212

536

if(debug){

213

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

537

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

214

538

}

215

539

216

540

/* Init GPGME */

217

541

gpgme_check_version(NULL);

218

542

rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

219

543

if(rc != GPG_ERR_NO_ERROR){

220

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

221

gpgme_strsource(rc), gpgme_strerror(rc));

544

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

545

gpgme_strsource(rc), gpgme_strerror(rc));

222

546

return false;

223

547

}

224

548

225

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

549

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

226

550

rc = gpgme_get_engine_info(&engine_info);

227

551

if(rc != GPG_ERR_NO_ERROR){

228

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

229

gpgme_strsource(rc), gpgme_strerror(rc));

552

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

553

gpgme_strsource(rc), gpgme_strerror(rc));

230

554

return false;

231

555

}

232

556

while(engine_info != NULL){

238

562

engine_info = engine_info->next;

239

563

}

240

564

if(engine_info == NULL){

241

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

565

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

566

tempdir);

242

567

return false;

243

568

}

244

569

245

570

/* Create new GPGME "context" */

246

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

571

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

247

572

if(rc != GPG_ERR_NO_ERROR){

248

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

249

gpgme_strsource(rc), gpgme_strerror(rc));

573

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

574

gpgme_strsource(rc), gpgme_strerror(rc));

250

575

return false;

251

576

}

252

577

261

586

* Decrypt OpenPGP data.

262

587

* Returns -1 on error

263

588

*/

589

__attribute__((nonnull, warn_unused_result))

264

590

static ssize_t pgp_packet_decrypt(const char *cryptotext,

265

591

size_t crypto_size,

266

char **plaintext){

592

char **plaintext,

593

mandos_context *mc){

267

594

gpgme_data_t dh_crypto, dh_plain;

268

595

gpgme_error_t rc;

269

596

ssize_t ret;

271

598

ssize_t plaintext_length = 0;

272

599

273

600

if(debug){

274

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

601

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

275

602

}

276

603

277

604

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

278

605

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

279

606

0);

280

607

if(rc != GPG_ERR_NO_ERROR){

281

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

282

gpgme_strsource(rc), gpgme_strerror(rc));

608

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

609

gpgme_strsource(rc), gpgme_strerror(rc));

283

610

return -1;

284

611

}

285

612

286

613

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

287

614

rc = gpgme_data_new(&dh_plain);

288

615

if(rc != GPG_ERR_NO_ERROR){

289

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

290

gpgme_strsource(rc), gpgme_strerror(rc));

616

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

617

gpgme_strsource(rc), gpgme_strerror(rc));

291

618

gpgme_data_release(dh_crypto);

292

619

return -1;

293

620

}

294

621

295

622

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

296

623

data buffer */

297

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

624

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

298

625

if(rc != GPG_ERR_NO_ERROR){

299

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

300

gpgme_strsource(rc), gpgme_strerror(rc));

626

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

627

gpgme_strsource(rc), gpgme_strerror(rc));

301

628

plaintext_length = -1;

302

629

if(debug){

303

630

gpgme_decrypt_result_t result;

304

result = gpgme_op_decrypt_result(mc.ctx);

631

result = gpgme_op_decrypt_result(mc->ctx);

305

632

if(result == NULL){

306

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

633

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

307

634

} else {

308

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

309

result->unsupported_algorithm);

310

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

311

result->wrong_key_usage);

635

if(result->unsupported_algorithm != NULL) {

636

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

637

result->unsupported_algorithm);

638

}

639

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

640

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

312

641

if(result->file_name != NULL){

313

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

642

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

314

643

}

315

gpgme_recipient_t recipient;

316

recipient = result->recipients;

317

while(recipient != NULL){

318

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

319

gpgme_pubkey_algo_name(recipient->pubkey_algo));

320

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

321

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

322

recipient->status == GPG_ERR_NO_SECKEY

323

? "No" : "Yes");

324

recipient = recipient->next;

644

645

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

646

r = r->next){

647

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

648

gpgme_pubkey_algo_name(r->pubkey_algo));

649

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

650

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

651

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

325

652

}

326

653

}

327

654

}

329

656

}

330

657

331

658

if(debug){

332

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

659

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

333

660

}

334

661

335

662

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

336

663

if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){

337

perror("gpgme_data_seek");

664

perror_plus("gpgme_data_seek");

338

665

plaintext_length = -1;

339

666

goto decrypt_end;

340

667

}

342

669

*plaintext = NULL;

343

670

while(true){

344

671

plaintext_capacity = incbuffer(plaintext,

345

(size_t)plaintext_length,

346

plaintext_capacity);

672

(size_t)plaintext_length,

673

plaintext_capacity);

347

674

if(plaintext_capacity == 0){

348

perror("incbuffer");

349

plaintext_length = -1;

350

goto decrypt_end;

675

perror_plus("incbuffer");

676

plaintext_length = -1;

677

goto decrypt_end;

351

678

}

352

679

353

680

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

358

685

break;

359

686

}

360

687

if(ret < 0){

361

perror("gpgme_data_read");

688

perror_plus("gpgme_data_read");

362

689

plaintext_length = -1;

363

690

goto decrypt_end;

364

691

}

366

693

}

367

694

368

695

if(debug){

369

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

696

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

370

697

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

371

698

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

372

699

}

383

710

return plaintext_length;

384

711

}

385

712

386

static const char * safer_gnutls_strerror(int value){

387

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

388

-Wunreachable-code */

389

if(ret == NULL)

390

ret = "(unknown)";

391

return ret;

713

__attribute__((warn_unused_result, const))

714

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

715

if(str == NULL)

716

return "(unknown)";

717

return str;

718

}

719

720

__attribute__((warn_unused_result))

721

static const char *safer_gnutls_strerror(int value){

722

const char *ret = gnutls_strerror(value);

723

return safe_string(ret);

392

724

}

393

725

394

726

/* GnuTLS log function callback */

727

__attribute__((nonnull))

395

728

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

396

729

const char* string){

397

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

730

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

398

731

}

399

732

733

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

400

734

static int init_gnutls_global(const char *pubkeyfilename,

401

const char *seckeyfilename){

735

const char *seckeyfilename,

736

const char *dhparamsfilename,

737

mandos_context *mc){

402

738

int ret;

403

739

404

740

if(debug){

405

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

406

}

407

408

ret = gnutls_global_init();

409

if(ret != GNUTLS_E_SUCCESS){

410

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

411

safer_gnutls_strerror(ret));

412

return -1;

741

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

413

742

}

414

743

415

744

if(debug){

421

750

}

422

751

423

752

/* OpenPGP credentials */

424

gnutls_certificate_allocate_credentials(&mc.cred);

753

ret = gnutls_certificate_allocate_credentials(&mc->cred);

425

754

if(ret != GNUTLS_E_SUCCESS){

426

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

427

from

428

-Wunreachable-code

429

*/

430

safer_gnutls_strerror(ret));

431

gnutls_global_deinit();

755

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

756

safer_gnutls_strerror(ret));

432

757

return -1;

433

758

}

434

759

435

760

if(debug){

436

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

437

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

438

seckeyfilename);

761

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

762

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

763

pubkeyfilename,

764

seckeyfilename);

439

765

}

440

766

767

#if GNUTLS_VERSION_NUMBER >= 0x030606

768

ret = gnutls_certificate_set_rawpk_key_file

769

(mc->cred, pubkeyfilename, seckeyfilename,

770

GNUTLS_X509_FMT_PEM, /* format */

771

NULL, /* pass */

772

/* key_usage */

773

GNUTLS_KEY_DIGITAL_SIGNATURE | GNUTLS_KEY_KEY_ENCIPHERMENT,

774

NULL, /* names */

775

0, /* names_length */

776

/* privkey_flags */

777

GNUTLS_PKCS_PLAIN | GNUTLS_PKCS_NULL_PASSWORD,

778

0); /* pkcs11_flags */

779

#elif GNUTLS_VERSION_NUMBER < 0x030600

441

780

ret = gnutls_certificate_set_openpgp_key_file

442

(mc.cred, pubkeyfilename, seckeyfilename,

781

(mc->cred, pubkeyfilename, seckeyfilename,

443

782

GNUTLS_OPENPGP_FMT_BASE64);

783

#else

784

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

785

#endif

444

786

if(ret != GNUTLS_E_SUCCESS){

445

fprintf(stderr,

446

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

447

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

448

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

449

safer_gnutls_strerror(ret));

787

fprintf_plus(stderr,

788

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

789

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

790

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

791

safer_gnutls_strerror(ret));

450

792

goto globalfail;

451

793

}

452

794

453

795

/* GnuTLS server initialization */

454

ret = gnutls_dh_params_init(&mc.dh_params);

455

if(ret != GNUTLS_E_SUCCESS){

456

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

457

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

458

goto globalfail;

459

}

460

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

461

if(ret != GNUTLS_E_SUCCESS){

462

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

463

safer_gnutls_strerror(ret));

464

goto globalfail;

465

}

466

467

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

796

ret = gnutls_dh_params_init(&mc->dh_params);

797

if(ret != GNUTLS_E_SUCCESS){

798

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

799

" initialization: %s\n",

800

safer_gnutls_strerror(ret));

801

goto globalfail;

802

}

803

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

804

if(dhparamsfilename != NULL){

805

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

806

do {

807

int dhpfile = open(dhparamsfilename, O_RDONLY);

808

if(dhpfile == -1){

809

perror_plus("open");

810

dhparamsfilename = NULL;

811

break;

812

}

813

size_t params_capacity = 0;

814

while(true){

815

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

816

(size_t)params.size,

817

(size_t)params_capacity);

818

if(params_capacity == 0){

819

perror_plus("incbuffer");

820

free(params.data);

821

params.data = NULL;

822

dhparamsfilename = NULL;

823

break;

824

}

825

ssize_t bytes_read = read(dhpfile,

826

params.data + params.size,

827

BUFFER_SIZE);

828

/* EOF */

829

if(bytes_read == 0){

830

break;

831

}

832

/* check bytes_read for failure */

833

if(bytes_read < 0){

834

perror_plus("read");

835

free(params.data);

836

params.data = NULL;

837

dhparamsfilename = NULL;

838

break;

839

}

840

params.size += (unsigned int)bytes_read;

841

}

842

ret = close(dhpfile);

843

if(ret == -1){

844

perror_plus("close");

845

}

846

if(params.data == NULL){

847

dhparamsfilename = NULL;

848

}

849

if(dhparamsfilename == NULL){

850

break;

851

}

852

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

853

GNUTLS_X509_FMT_PEM);

854

if(ret != GNUTLS_E_SUCCESS){

855

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

856

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

857

safer_gnutls_strerror(ret));

858

dhparamsfilename = NULL;

859

}

860

free(params.data);

861

} while(false);

862

}

863

if(dhparamsfilename == NULL){

864

if(mc->dh_bits == 0){

865

#if GNUTLS_VERSION_NUMBER < 0x030600

866

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

867

/* Try to read the private key file */

868

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

869

do {

870

int secfile = open(seckeyfilename, O_RDONLY);

871

if(secfile == -1){

872

perror_plus("open");

873

break;

874

}

875

size_t buffer_capacity = 0;

876

while(true){

877

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

878

(size_t)buffer.size,

879

(size_t)buffer_capacity);

880

if(buffer_capacity == 0){

881

perror_plus("incbuffer");

882

free(buffer.data);

883

buffer.data = NULL;

884

break;

885

}

886

ssize_t bytes_read = read(secfile,

887

buffer.data + buffer.size,

888

BUFFER_SIZE);

889

/* EOF */

890

if(bytes_read == 0){

891

break;

892

}

893

/* check bytes_read for failure */

894

if(bytes_read < 0){

895

perror_plus("read");

896

free(buffer.data);

897

buffer.data = NULL;

898

break;

899

}

900

buffer.size += (unsigned int)bytes_read;

901

}

902

close(secfile);

903

} while(false);

904

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

905

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

906

if(buffer.data != NULL){

907

{

908

gnutls_openpgp_privkey_t privkey = NULL;

909

ret = gnutls_openpgp_privkey_init(&privkey);

910

if(ret != GNUTLS_E_SUCCESS){

911

fprintf_plus(stderr, "Error initializing OpenPGP key"

912

" structure: %s",

913

safer_gnutls_strerror(ret));

914

free(buffer.data);

915

buffer.data = NULL;

916

} else {

917

ret = gnutls_openpgp_privkey_import

918

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

919

if(ret != GNUTLS_E_SUCCESS){

920

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

921

safer_gnutls_strerror(ret));

922

privkey = NULL;

923

}

924

free(buffer.data);

925

buffer.data = NULL;

926

if(privkey != NULL){

927

/* Use private key to suggest an appropriate

928

sec_param */

929

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

930

gnutls_openpgp_privkey_deinit(privkey);

931

if(debug){

932

fprintf_plus(stderr, "This OpenPGP key implies using"

933

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

934

safe_string(gnutls_sec_param_get_name

935

(sec_param)));

936

}

937

}

938

}

939

}

940

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

941

/* Err on the side of caution */

942

sec_param = GNUTLS_SEC_PARAM_ULTRA;

943

if(debug){

944

fprintf_plus(stderr, "Falling back to security parameter"

945

" \"%s\"\n",

946

safe_string(gnutls_sec_param_get_name

947

(sec_param)));

948

}

949

}

950

}

951

unsigned int uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

952

if(uret != 0){

953

mc->dh_bits = uret;

954

if(debug){

955

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

956

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

957

safe_string(gnutls_sec_param_get_name

958

(sec_param)),

959

mc->dh_bits);

960

}

961

} else {

962

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

963

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

964

safe_string(gnutls_sec_param_get_name

965

(sec_param)),

966

safer_gnutls_strerror(ret));

967

goto globalfail;

968

}

969

#endif

970

} else { /* dh_bits != 0 */

971

if(debug){

972

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

973

mc->dh_bits);

974

}

975

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

976

if(ret != GNUTLS_E_SUCCESS){

977

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

978

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

979

safer_gnutls_strerror(ret));

980

goto globalfail;

981

}

982

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

983

}

984

}

468

985

469

986

return 0;

470

987

471

988

globalfail:

472

989

473

gnutls_certificate_free_credentials(mc.cred);

474

gnutls_global_deinit();

475

gnutls_dh_params_deinit(mc.dh_params);

990

gnutls_certificate_free_credentials(mc->cred);

991

gnutls_dh_params_deinit(mc->dh_params);

476

992

return -1;

477

993

}

478

994

479

static int init_gnutls_session(gnutls_session_t *session){

995

__attribute__((nonnull, warn_unused_result))

996

static int init_gnutls_session(gnutls_session_t *session,

997

mandos_context *mc){

480

998

int ret;

481

999

/* GnuTLS session creation */

482

1000

do {

483

ret = gnutls_init(session, GNUTLS_SERVER);

1001

ret = gnutls_init(session, (GNUTLS_SERVER

1002

#if GNUTLS_VERSION_NUMBER >= 0x030506

1003

| GNUTLS_NO_TICKETS

1004

#endif

1005

#if GNUTLS_VERSION_NUMBER >= 0x030606

1006

| GNUTLS_ENABLE_RAWPK

1007

#endif

1008

));

484

1009

if(quit_now){

485

1010

return -1;

486

1011

}

487

1012

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

488

1013

if(ret != GNUTLS_E_SUCCESS){

489

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

490

safer_gnutls_strerror(ret));

1014

fprintf_plus(stderr,

1015

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

1016

safer_gnutls_strerror(ret));

491

1017

}

492

1018

493

1019

{

494

1020

const char *err;

495

1021

do {

496

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

1022

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

497

1023

if(quit_now){

498

1024

gnutls_deinit(*session);

499

1025

return -1;

500

1026

}

501

1027

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

502

1028

if(ret != GNUTLS_E_SUCCESS){

503

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

504

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

505

safer_gnutls_strerror(ret));

1029

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

1030

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

1031

safer_gnutls_strerror(ret));

506

1032

gnutls_deinit(*session);

507

1033

return -1;

508

1034

}

510

1036

511

1037

do {

512

1038

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

513

mc.cred);

1039

mc->cred);

514

1040

if(quit_now){

515

1041

gnutls_deinit(*session);

516

1042

return -1;

517

1043

}

518

1044

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

519

1045

if(ret != GNUTLS_E_SUCCESS){

520

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

521

safer_gnutls_strerror(ret));

1046

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

1047

safer_gnutls_strerror(ret));

522

1048

gnutls_deinit(*session);

523

1049

return -1;

524

1050

}

526

1052

/* ignore client certificate if any. */

527

1053

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

528

1054

529

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

530

531

1055

return 0;

532

1056

}

533

1057

535

1059

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

536

1060

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

537

1061

1062

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

1063

__attribute__((nonnull, warn_unused_result))

1064

static bool add_delete_local_route(const bool add,

1065

const char *address,

1066

AvahiIfIndex if_index){

1067

int ret;

1068

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

1069

char add_arg[] = "add";

1070

char delete_arg[] = "delete";

1071

char debug_flag[] = "--debug";

1072

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

1073

if(pluginhelperdir == NULL){

1074

if(debug){

1075

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

1076

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

1077

}

1078

return false;

1079

}

1080

1081

char interface[IF_NAMESIZE];

1082

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

1083

perror_plus("if_indextoname");

1084

return false;

1085

}

1086

1087

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

1088

if(devnull == -1){

1089

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

1090

return false;

1091

}

1092

pid_t pid = fork();

1093

if(pid == 0){

1094

/* Child */

1095

/* Raise privileges */

1096

errno = raise_privileges_permanently();

1097

if(errno != 0){

1098

perror_plus("Failed to raise privileges");

1099

/* _exit(EX_NOPERM); */

1100

} else {

1101

/* Set group */

1102

errno = 0;

1103

ret = setgid(0);

1104

if(ret == -1){

1105

perror_plus("setgid");

1106

close(devnull);

1107

_exit(EX_NOPERM);

1108

}

1109

/* Reset supplementary groups */

1110

errno = 0;

1111

ret = setgroups(0, NULL);

1112

if(ret == -1){

1113

perror_plus("setgroups");

1114

close(devnull);

1115

_exit(EX_NOPERM);

1116

}

1117

}

1118

ret = dup2(devnull, STDIN_FILENO);

1119

if(ret == -1){

1120

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

1121

close(devnull);

1122

_exit(EX_OSERR);

1123

}

1124

ret = close(devnull);

1125

if(ret == -1){

1126

perror_plus("close");

1127

}

1128

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1129

if(ret == -1){

1130

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

1131

_exit(EX_OSERR);

1132

}

1133

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

1134

O_RDONLY

1135

| O_DIRECTORY

1136

| O_PATH

1137

| O_CLOEXEC));

1138

if(helperdir_fd == -1){

1139

perror_plus("open");

1140

_exit(EX_UNAVAILABLE);

1141

}

1142

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

1143

helper, O_RDONLY));

1144

if(helper_fd == -1){

1145

perror_plus("openat");

1146

close(helperdir_fd);

1147

_exit(EX_UNAVAILABLE);

1148

}

1149

close(helperdir_fd);

1150

#ifdef __GNUC__

1151

#pragma GCC diagnostic push

1152

#pragma GCC diagnostic ignored "-Wcast-qual"

1153

#endif

1154

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

1155

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

1156

interface, debug ? debug_flag : NULL, NULL },

1157

environ) == -1){

1158

#ifdef __GNUC__

1159

#pragma GCC diagnostic pop

1160

#endif

1161

perror_plus("fexecve");

1162

_exit(EXIT_FAILURE);

1163

}

1164

}

1165

if(pid == -1){

1166

perror_plus("fork");

1167

close(devnull);

1168

return false;

1169

}

1170

ret = close(devnull);

1171

if(ret == -1){

1172

perror_plus("close");

1173

}

1174

int status;

1175

pid_t pret = -1;

1176

errno = 0;

1177

do {

1178

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

1179

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

1180

int errno_raising = 0;

1181

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

1182

errno_raising = errno;

1183

perror_plus("Failed to raise privileges in order to"

1184

" kill helper program");

1185

}

1186

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

1187

perror_plus("kill");

1188

}

1189

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

1190

perror_plus("Failed to lower privileges after killing"

1191

" helper program");

1192

}

1193

return false;

1194

}

1195

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

1196

if(pret == -1){

1197

perror_plus("waitpid");

1198

return false;

1199

}

1200

if(WIFEXITED(status)){

1201

if(WEXITSTATUS(status) != 0){

1202

fprintf_plus(stderr, "Error: iprouteadddel exited"

1203

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

1204

return false;

1205

}

1206

return true;

1207

}

1208

if(WIFSIGNALED(status)){

1209

fprintf_plus(stderr, "Error: iprouteadddel died by"

1210

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

1211

return false;

1212

}

1213

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

1214

return false;

1215

}

1216

1217

__attribute__((nonnull, warn_unused_result))

1218

static bool add_local_route(const char *address,

1219

AvahiIfIndex if_index){

1220

if(debug){

1221

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

1222

}

1223

return add_delete_local_route(true, address, if_index);

1224

}

1225

1226

__attribute__((nonnull, warn_unused_result))

1227

static bool delete_local_route(const char *address,

1228

AvahiIfIndex if_index){

1229

if(debug){

1230

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

1231

}

1232

return add_delete_local_route(false, address, if_index);

1233

}

1234

538

1235

/* Called when a Mandos server is found */

539

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

1236

__attribute__((nonnull, warn_unused_result))

1237

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

540

1238

AvahiIfIndex if_index,

541

int af){

1239

int af, mandos_context *mc){

542

1240

int ret, tcp_sd = -1;

543

1241

ssize_t sret;

544

union {

545

struct sockaddr_in in;

546

struct sockaddr_in6 in6;

547

} to;

1242

struct sockaddr_storage to;

548

1243

char *buffer = NULL;

549

1244

char *decrypted_buffer = NULL;

550

1245

size_t buffer_length = 0;

553

1248

int retval = -1;

554

1249

gnutls_session_t session;

555

1250

int pf; /* Protocol family */

1251

bool route_added = false;

556

1252

557

1253

errno = 0;

558

1254

569

1265

pf = PF_INET;

570

1266

break;

571

1267

default:

572

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

1268

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

573

1269

errno = EINVAL;

574

1270

return -1;

575

1271

}

576

1272

577

ret = init_gnutls_session(&session);

1273

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

1274

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

1275

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

1276

bool match = false;

1277

{

1278

char *interface = NULL;

1279

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

1280

mc->interfaces_size,

1281

interface))){

1282

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

1283

match = true;

1284

break;

1285

}

1286

}

1287

}

1288

if(not match){

1289

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

1290

connect to the server */

1291

if(debug){

1292

char interface[IF_NAMESIZE];

1293

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

1294

perror_plus("if_indextoname");

1295

} else {

1296

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

1297

" \"%s\"\n",

1298

if_indextoname((unsigned int)if_index,

1299

interface));

1300

}

1301

}

1302

return -1;

1303

}

1304

}

1305

1306

ret = init_gnutls_session(&session, mc);

578

1307

if(ret != 0){

579

1308

return -1;

580

1309

}

581

1310

582

1311

if(debug){

583

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

584

"\n", ip, port);

1312

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

1313

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

585

1314

}

586

1315

587

tcp_sd = socket(pf, SOCK_STREAM, 0);

1316

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

588

1317

if(tcp_sd < 0){

589

1318

int e = errno;

590

perror("socket");

1319

perror_plus("socket");

591

1320

errno = e;

592

1321

goto mandos_end;

593

1322

}

597

1326

goto mandos_end;

598

1327

}

599

1328

600

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

601

1329

if(af == AF_INET6){

602

to.in6.sin6_family = (sa_family_t)af;

603

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

1330

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

1331

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

1332

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

604

1333

} else { /* IPv4 */

605

to.in.sin_family = (sa_family_t)af;

606

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

1334

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

1335

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

1336

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

607

1337

}

608

1338

if(ret < 0 ){

609

1339

int e = errno;

610

perror("inet_pton");

1340

perror_plus("inet_pton");

611

1341

errno = e;

612

1342

goto mandos_end;

613

1343

}

614

1344

if(ret == 0){

615

1345

int e = errno;

616

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

1346

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

617

1347

errno = e;

618

1348

goto mandos_end;

619

1349

}

620

1350

if(af == AF_INET6){

621

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

622

-Wconversion and

623

-Wunreachable-code */

624

625

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

626

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

627

-Wunreachable-code*/

1351

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

1352

if(IN6_IS_ADDR_LINKLOCAL

1353

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

628

1354

if(if_index == AVAHI_IF_UNSPEC){

629

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

630

" without a network interface\n");

1355

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

1356

" incomplete without a network interface\n");

631

1357

errno = EINVAL;

632

1358

goto mandos_end;

633

1359

}

634

1360

/* Set the network interface number as scope */

635

to.in6.sin6_scope_id = (uint32_t)if_index;

1361

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

636

1362

}

637

1363

} else {

638

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

639

-Wconversion and

640

-Wunreachable-code */

1364

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

641

1365

}

642

1366

643

1367

if(quit_now){

649

1373

if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){

650

1374

char interface[IF_NAMESIZE];

651

1375

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

652

perror("if_indextoname");

1376

perror_plus("if_indextoname");

653

1377

} else {

654

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

655

ip, interface, port);

1378

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

1379

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

656

1380

}

657

1381

} else {

658

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

659

port);

1382

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

1383

ip, (uintmax_t)port);

660

1384

}

661

1385

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

662

1386

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

663

const char *pcret;

664

if(af == AF_INET6){

665

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

666

sizeof(addrstr));

667

} else {

668

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

669

sizeof(addrstr));

670

}

671

if(pcret == NULL){

672

perror("inet_ntop");

673

} else {

674

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

675

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

676

}

677

}

678

}

679

680

if(quit_now){

681

errno = EINTR;

682

goto mandos_end;

683

}

684

685

if(af == AF_INET6){

686

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

687

} else {

688

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

689

}

690

if(ret < 0){

691

int e = errno;

692

perror("connect");

693

errno = e;

694

goto mandos_end;

695

}

696

697

if(quit_now){

698

errno = EINTR;

699

goto mandos_end;

1387

if(af == AF_INET6){

1388

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

1389

sizeof(struct sockaddr_in6),

1390

addrstr, sizeof(addrstr), NULL, 0,

1391

NI_NUMERICHOST);

1392

} else {

1393

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

1394

sizeof(struct sockaddr_in),

1395

addrstr, sizeof(addrstr), NULL, 0,

1396

NI_NUMERICHOST);

1397

}

1398

if(ret == EAI_SYSTEM){

1399

perror_plus("getnameinfo");

1400

} else if(ret != 0) {

1401

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

1402

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

1403

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

1404

}

1405

}

1406

1407

if(quit_now){

1408

errno = EINTR;

1409

goto mandos_end;

1410

}

1411

1412

while(true){

1413

if(af == AF_INET6){

1414

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

1415

sizeof(struct sockaddr_in6));

1416

} else {

1417

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

1418

sizeof(struct sockaddr_in));

1419

}

1420

if(ret < 0){

1421

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

1422

and if_index != AVAHI_IF_UNSPEC

1423

and connect_to == NULL

1424

and not route_added and

1425

((af == AF_INET6 and not

1426

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1427

&to)->sin6_addr)))

1428

or (af == AF_INET and

1429

/* Not a a IPv4LL address */

1430

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

1431

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

1432

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

1433

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

1434

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

1435

connect to a Mandos server announced by Avahi on a server

1436

host with a global address. Work around this by retrying

1437

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

1438

1439

Avahi bug reference:

1440

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

1441

https://bugs.debian.org/587961

1442

*/

1443

if(debug){

1444

fprintf_plus(stderr, "Mandos server unreachable, trying"

1445

" direct route\n");

1446

}

1447

int e = errno;

1448

route_added = add_local_route(ip, if_index);

1449

if(route_added){

1450

continue;

1451

}

1452

errno = e;

1453

}

1454

if(errno != ECONNREFUSED or debug){

1455

int e = errno;

1456

perror_plus("connect");

1457

errno = e;

1458

}

1459

goto mandos_end;

1460

}

1461

1462

if(quit_now){

1463

errno = EINTR;

1464

goto mandos_end;

1465

}

1466

break;

700

1467

}

701

1468

702

1469

const char *out = mandos_protocol_version;

704

1471

while(true){

705

1472

size_t out_size = strlen(out);

706

1473

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

707

out_size - written));

1474

out_size - written));

708

1475

if(ret == -1){

709

1476

int e = errno;

710

perror("write");

1477

perror_plus("write");

711

1478

errno = e;

712

1479

goto mandos_end;

713

1480

}

730

1497

}

731

1498

732

1499

if(debug){

733

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

1500

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

734

1501

}

735

1502

736

1503

if(quit_now){

738

1505

goto mandos_end;

739

1506

}

740

1507

741

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1508

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

1509

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

1510

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

1511

gnutls_transport_set_ptr(session,

1512

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

742

1513

743

1514

if(quit_now){

744

1515

errno = EINTR;

755

1526

756

1527

if(ret != GNUTLS_E_SUCCESS){

757

1528

if(debug){

758

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

1529

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

759

1530

gnutls_perror(ret);

760

1531

}

761

1532

errno = EPROTO;

765

1536

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

766

1537

767

1538

if(debug){

768

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

769

ip);

1539

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

1540

" %s\n", ip);

770

1541

}

771

1542

772

1543

while(true){

777

1548

}

778

1549

779

1550

buffer_capacity = incbuffer(&buffer, buffer_length,

780

buffer_capacity);

1551

buffer_capacity);

781

1552

if(buffer_capacity == 0){

782

1553

int e = errno;

783

perror("incbuffer");

1554

perror_plus("incbuffer");

784

1555

errno = e;

785

1556

goto mandos_end;

786

1557

}

810

1581

}

811

1582

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

812

1583

if(ret < 0){

813

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

1584

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

1585

"***\n");

814

1586

gnutls_perror(ret);

815

1587

errno = EPROTO;

816

1588

goto mandos_end;

817

1589

}

818

1590

break;

819

1591

default:

820

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

821

" encrypted session with Mandos server\n");

1592

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

1593

" encrypted session with Mandos server\n");

822

1594

gnutls_bye(session, GNUTLS_SHUT_RDWR);

823

1595

errno = EIO;

824

1596

goto mandos_end;

829

1601

}

830

1602

831

1603

if(debug){

832

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

1604

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

833

1605

}

834

1606

835

1607

if(quit_now){

847

1619

848

1620

if(buffer_length > 0){

849

1621

ssize_t decrypted_buffer_size;

850

decrypted_buffer_size = pgp_packet_decrypt(buffer,

851

buffer_length,

852

&decrypted_buffer);

1622

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1623

&decrypted_buffer, mc);

853

1624

if(decrypted_buffer_size >= 0){

854

1625

1626

clearerr(stdout);

855

1627

written = 0;

856

1628

while(written < (size_t) decrypted_buffer_size){

857

1629

if(quit_now){

865

1637

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

866

1638

int e = errno;

867

1639

if(debug){

868

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

869

strerror(errno));

1640

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

1641

strerror(errno));

870

1642

}

871

1643

errno = e;

872

1644

goto mandos_end;

873

1645

}

874

1646

written += (size_t)ret;

875

1647

}

1648

ret = fflush(stdout);

1649

if(ret != 0){

1650

int e = errno;

1651

if(debug){

1652

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

1653

strerror(errno));

1654

}

1655

errno = e;

1656

goto mandos_end;

1657

}

876

1658

retval = 0;

877

1659

}

878

1660

}

881

1663

882

1664

mandos_end:

883

1665

{

1666

if(route_added){

1667

if(not delete_local_route(ip, if_index)){

1668

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

1669

" interface %d", ip, if_index);

1670

}

1671

}

884

1672

int e = errno;

885

1673

free(decrypted_buffer);

886

1674

free(buffer);

887

1675

if(tcp_sd >= 0){

888

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

1676

ret = close(tcp_sd);

889

1677

}

890

1678

if(ret == -1){

891

1679

if(e == 0){

892

1680

e = errno;

893

1681

}

894

perror("close");

1682

perror_plus("close");

895

1683

}

896

1684

gnutls_deinit(session);

1685

errno = e;

897

1686

if(quit_now){

898

e = EINTR;

1687

errno = EINTR;

899

1688

retval = -1;

900

1689

}

901

errno = e;

902

1690

}

903

1691

return retval;

904

1692

}

916

1704

AVAHI_GCC_UNUSED AvahiStringList *txt,

917

1705

AVAHI_GCC_UNUSED AvahiLookupResultFlags

918

1706

flags,

919

AVAHI_GCC_UNUSED void* userdata){

920

assert(r);

1707

void *mc){

1708

if(r == NULL){

1709

return;

1710

}

921

1711

922

1712

/* Called whenever a service has been resolved successfully or

923

1713

timed out */

924

1714

925

1715

if(quit_now){

1716

avahi_s_service_resolver_free(r);

926

1717

return;

927

1718

}

928

1719

929

1720

switch(event){

930

1721

default:

931

1722

case AVAHI_RESOLVER_FAILURE:

932

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

933

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

934

avahi_strerror(avahi_server_errno(mc.server)));

1723

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

1724

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

1725

domain,

1726

avahi_strerror(avahi_server_errno

1727

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

935

1728

break;

936

1729

937

1730

case AVAHI_RESOLVER_FOUND:

939

1732

char ip[AVAHI_ADDRESS_STR_MAX];

940

1733

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

941

1734

if(debug){

942

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

943

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

944

ip, (intmax_t)interface, port);

1735

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

1736

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

1737

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

945

1738

}

946

int ret = start_mandos_communication(ip, port, interface,

947

avahi_proto_to_af(proto));

1739

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

1740

interface,

1741

avahi_proto_to_af(proto),

1742

mc);

948

1743

if(ret == 0){

949

avahi_simple_poll_quit(mc.simple_poll);

1744

avahi_simple_poll_quit(simple_poll);

1745

} else {

1746

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

1747

avahi_proto_to_af(proto),

1748

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

1749

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

1750

" list\n", name);

1751

}

950

1752

}

951

1753

}

952

1754

}

962

1764

const char *domain,

963

1765

AVAHI_GCC_UNUSED AvahiLookupResultFlags

964

1766

flags,

965

AVAHI_GCC_UNUSED void* userdata){

966

assert(b);

1767

void *mc){

1768

if(b == NULL){

1769

return;

1770

}

967

1771

968

1772

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

969

1773

is removed from the LAN */

976

1780

default:

977

1781

case AVAHI_BROWSER_FAILURE:

978

1782

979

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

980

avahi_strerror(avahi_server_errno(mc.server)));

981

avahi_simple_poll_quit(mc.simple_poll);

1783

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

1784

avahi_strerror(avahi_server_errno

1785

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

1786

avahi_simple_poll_quit(simple_poll);

982

1787

return;

983

1788

984

1789

case AVAHI_BROWSER_NEW:

987

1792

the callback function is called the Avahi server will free the

988

1793

resolver for us. */

989

1794

990

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

991

name, type, domain, protocol, 0,

992

resolve_callback, NULL) == NULL)

993

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

994

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

1795

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

1796

interface, protocol, name, type,

1797

domain, protocol, 0,

1798

resolve_callback, mc) == NULL)

1799

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

1800

" %s\n", name,

1801

avahi_strerror(avahi_server_errno

1802

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

995

1803

break;

996

1804

997

1805

case AVAHI_BROWSER_REMOVE:

1000

1808

case AVAHI_BROWSER_ALL_FOR_NOW:

1001

1809

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1002

1810

if(debug){

1003

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

1811

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

1812

" searching...\n");

1004

1813

}

1005

1814

break;

1006

1815

}

1007

1816

}

1008

1817

1009

/* stop main loop after sigterm has been called */

1818

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

1010

1819

static void handle_sigterm(int sig){

1011

1820

if(quit_now){

1012

1821

return;

1014

1823

quit_now = 1;

1015

1824

signal_received = sig;

1016

1825

int old_errno = errno;

1017

if(mc.simple_poll != NULL){

1018

avahi_simple_poll_quit(mc.simple_poll);

1019

}

1020

errno = old_errno;

1826

/* set main loop to exit */

1827

if(simple_poll != NULL){

1828

avahi_simple_poll_quit(simple_poll);

1829

}

1830

errno = old_errno;

1831

}

1832

1833

__attribute__((nonnull, warn_unused_result))

1834

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

1835

int ret;

1836

int old_errno;

1837

1838

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

1839

if(s < 0){

1840

old_errno = errno;

1841

perror_plus("socket");

1842

errno = old_errno;

1843

return false;

1844

}

1845

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

1846

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

1847

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1848

if(ret == -1){

1849

if(debug){

1850

old_errno = errno;

1851

perror_plus("ioctl SIOCGIFFLAGS");

1852

errno = old_errno;

1853

}

1854

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

1855

old_errno = errno;

1856

perror_plus("close");

1857

errno = old_errno;

1858

}

1859

return false;

1860

}

1861

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

1862

old_errno = errno;

1863

perror_plus("close");

1864

errno = old_errno;

1865

}

1866

return true;

1867

}

1868

1869

__attribute__((nonnull, warn_unused_result))

1870

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

1871

1872

/* Reject the loopback device */

1873

if(ifr->ifr_flags & IFF_LOOPBACK){

1874

if(debug){

1875

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

1876

ifname);

1877

}

1878

return false;

1879

}

1880

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

1881

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

1882

if(debug){

1883

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

1884

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

1885

}

1886

return true;

1887

}

1888

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

1889

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

1890

if(debug){

1891

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1892

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

1893

}

1894

return false;

1895

}

1896

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

1897

if(ifr->ifr_flags & IFF_NOARP){

1898

if(debug){

1899

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

1900

ifname);

1901

}

1902

return false;

1903

}

1904

1905

/* Accept this device */

1906

if(debug){

1907

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

1908

}

1909

return true;

1910

}

1911

1912

/*

1913

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

1914

* corresponds to an acceptable network device.

1915

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

1916

*/

1917

__attribute__((nonnull, warn_unused_result))

1918

int good_interface(const struct dirent *if_entry){

1919

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

1920

return 0;

1921

}

1922

1923

struct ifreq ifr;

1924

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

1925

if(debug){

1926

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

1927

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

1928

}

1929

return 0;

1930

}

1931

1932

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

1933

return 0;

1934

}

1935

return 1;

1936

}

1937

1938

/*

1939

* This function determines if a network interface is up.

1940

*/

1941

__attribute__((nonnull, warn_unused_result))

1942

bool interface_is_up(const char *interface){

1943

struct ifreq ifr;

1944

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

1945

if(debug){

1946

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

1947

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

1948

}

1949

return false;

1950

}

1951

1952

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

1953

}

1954

1955

/*

1956

* This function determines if a network interface is running

1957

*/

1958

__attribute__((nonnull, warn_unused_result))

1959

bool interface_is_running(const char *interface){

1960

struct ifreq ifr;

1961

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

1962

if(debug){

1963

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

1964

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

1965

}

1966

return false;

1967

}

1968

1969

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

1970

}

1971

1972

__attribute__((nonnull, pure, warn_unused_result))

1973

int notdotentries(const struct dirent *direntry){

1974

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

1975

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

1976

and (direntry->d_name[1] == '\0'

1977

or (direntry->d_name[1] == '.'

1978

and direntry->d_name[2] == '\0'))){

1979

return 0;

1980

}

1981

return 1;

1982

}

1983

1984

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

1985

__attribute__((nonnull, warn_unused_result))

1986

int runnable_hook(const struct dirent *direntry){

1987

int ret;

1988

size_t sret;

1989

struct stat st;

1990

1991

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

1992

/* Empty name? */

1993

return 0;

1994

}

1995

1996

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

1997

"abcdefghijklmnopqrstuvwxyz"

1998

"0123456789"

1999

"_.-");

2000

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

2001

/* Contains non-allowed characters */

2002

if(debug){

2003

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

2004

direntry->d_name);

2005

}

2006

return 0;

2007

}

2008

2009

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

2010

if(ret == -1){

2011

if(debug){

2012

perror_plus("Could not stat hook");

2013

}

2014

return 0;

2015

}

2016

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

2017

/* Not a regular file */

2018

if(debug){

2019

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

2020

direntry->d_name);

2021

}

2022

return 0;

2023

}

2024

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

2025

/* Not executable */

2026

if(debug){

2027

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

2028

direntry->d_name);

2029

}

2030

return 0;

2031

}

2032

if(debug){

2033

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

2034

direntry->d_name);

2035

}

2036

return 1;

2037

}

2038

2039

__attribute__((nonnull, warn_unused_result))

2040

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

2041

mandos_context *mc){

2042

int ret;

2043

struct timespec now;

2044

struct timespec waited_time;

2045

intmax_t block_time;

2046

2047

while(true){

2048

if(mc->current_server == NULL){

2049

if(debug){

2050

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

2051

" No timeout!\n");

2052

}

2053

ret = avahi_simple_poll_iterate(s, -1);

2054

} else {

2055

if(debug){

2056

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

2057

" it, or wait\n");

2058

}

2059

/* the current time */

2060

ret = clock_gettime(CLOCK_MONOTONIC, &now);

2061

if(ret == -1){

2062

perror_plus("clock_gettime");

2063

return -1;

2064

}

2065

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

2066

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

2067

waited_time.tv_sec = (now.tv_sec

2068

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

2069

waited_time.tv_nsec = (now.tv_nsec

2070

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

2071

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

2072

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

2073

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

2074

block_time = ((retry_interval

2075

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

2076

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

2077

2078

if(debug){

2079

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

2080

block_time);

2081

}

2082

2083

if(block_time <= 0){

2084

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

2085

mc->current_server->port,

2086

mc->current_server->if_index,

2087

mc->current_server->af, mc);

2088

if(ret == 0){

2089

avahi_simple_poll_quit(s);

2090

return 0;

2091

}

2092

ret = clock_gettime(CLOCK_MONOTONIC,

2093

&mc->current_server->last_seen);

2094

if(ret == -1){

2095

perror_plus("clock_gettime");

2096

return -1;

2097

}

2098

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

2099

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

2100

servers, but don't block */

2101

}

2102

2103

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

2104

}

2105

if(ret != 0){

2106

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

2107

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

2108

}

2109

}

2110

}

2111

}

2112

2113

__attribute__((nonnull))

2114

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

2115

const float delay){

2116

struct dirent **direntries = NULL;

2117

if(hookdir_fd == -1){

2118

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

2119

| O_CLOEXEC);

2120

if(hookdir_fd == -1){

2121

if(errno == ENOENT){

2122

if(debug){

2123

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

2124

" found\n", hookdir);

2125

}

2126

} else {

2127

perror_plus("open");

2128

}

2129

return;

2130

}

2131

}

2132

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

2133

if(devnull == -1){

2134

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

2135

return;

2136

}

2137

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

2138

runnable_hook, alphasort);

2139

if(numhooks == -1){

2140

perror_plus("scandir");

2141

close(devnull);

2142

return;

2143

}

2144

struct dirent *direntry;

2145

int ret;

2146

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

2147

direntry = direntries[i];

2148

if(debug){

2149

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

2150

direntry->d_name);

2151

}

2152

pid_t hook_pid = fork();

2153

if(hook_pid == 0){

2154

/* Child */

2155

/* Raise privileges */

2156

errno = raise_privileges_permanently();

2157

if(errno != 0){

2158

perror_plus("Failed to raise privileges");

2159

_exit(EX_NOPERM);

2160

}

2161

/* Set group */

2162

errno = 0;

2163

ret = setgid(0);

2164

if(ret == -1){

2165

perror_plus("setgid");

2166

_exit(EX_NOPERM);

2167

}

2168

/* Reset supplementary groups */

2169

errno = 0;

2170

ret = setgroups(0, NULL);

2171

if(ret == -1){

2172

perror_plus("setgroups");

2173

_exit(EX_NOPERM);

2174

}

2175

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

2176

if(ret == -1){

2177

perror_plus("setenv");

2178

_exit(EX_OSERR);

2179

}

2180

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

2181

if(ret == -1){

2182

perror_plus("setenv");

2183

_exit(EX_OSERR);

2184

}

2185

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

2186

if(ret == -1){

2187

perror_plus("setenv");

2188

_exit(EX_OSERR);

2189

}

2190

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

2191

if(ret == -1){

2192

perror_plus("setenv");

2193

_exit(EX_OSERR);

2194

}

2195

char *delaystring;

2196

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

2197

if(ret == -1){

2198

perror_plus("asprintf");

2199

_exit(EX_OSERR);

2200

}

2201

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

2202

if(ret == -1){

2203

free(delaystring);

2204

perror_plus("setenv");

2205

_exit(EX_OSERR);

2206

}

2207

free(delaystring);

2208

if(connect_to != NULL){

2209

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

2210

if(ret == -1){

2211

perror_plus("setenv");

2212

_exit(EX_OSERR);

2213

}

2214

}

2215

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

2216

direntry->d_name,

2217

O_RDONLY));

2218

if(hook_fd == -1){

2219

perror_plus("openat");

2220

_exit(EXIT_FAILURE);

2221

}

2222

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

2223

perror_plus("close");

2224

_exit(EXIT_FAILURE);

2225

}

2226

ret = dup2(devnull, STDIN_FILENO);

2227

if(ret == -1){

2228

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

2229

_exit(EX_OSERR);

2230

}

2231

ret = close(devnull);

2232

if(ret == -1){

2233

perror_plus("close");

2234

_exit(EX_OSERR);

2235

}

2236

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2237

if(ret == -1){

2238

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

2239

_exit(EX_OSERR);

2240

}

2241

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

2242

environ) == -1){

2243

perror_plus("fexecve");

2244

_exit(EXIT_FAILURE);

2245

}

2246

} else {

2247

if(hook_pid == -1){

2248

perror_plus("fork");

2249

free(direntry);

2250

continue;

2251

}

2252

int status;

2253

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

2254

perror_plus("waitpid");

2255

free(direntry);

2256

continue;

2257

}

2258

if(WIFEXITED(status)){

2259

if(WEXITSTATUS(status) != 0){

2260

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

2261

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

2262

WEXITSTATUS(status));

2263

free(direntry);

2264

continue;

2265

}

2266

} else if(WIFSIGNALED(status)){

2267

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

2268

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

2269

WTERMSIG(status));

2270

free(direntry);

2271

continue;

2272

} else {

2273

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

2274

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

2275

free(direntry);

2276

continue;

2277

}

2278

}

2279

if(debug){

2280

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

2281

direntry->d_name);

2282

}

2283

free(direntry);

2284

}

2285

free(direntries);

2286

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

2287

perror_plus("close");

2288

} else {

2289

hookdir_fd = -1;

2290

}

2291

close(devnull);

2292

}

2293

2294

__attribute__((nonnull, warn_unused_result))

2295

int bring_up_interface(const char *const interface,

2296

const float delay){

2297

int old_errno = errno;

2298

int ret;

2299

struct ifreq network;

2300

unsigned int if_index = if_nametoindex(interface);

2301

if(if_index == 0){

2302

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

2303

errno = old_errno;

2304

return ENXIO;

2305

}

2306

2307

if(quit_now){

2308

errno = old_errno;

2309

return EINTR;

2310

}

2311

2312

if(not interface_is_up(interface)){

2313

int ret_errno = 0;

2314

int ioctl_errno = 0;

2315

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

2316

ret_errno = errno;

2317

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

2318

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

2319

errno = old_errno;

2320

return ret_errno;

2321

}

2322

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

2323

2324

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

2325

if(sd == -1){

2326

ret_errno = errno;

2327

perror_plus("socket");

2328

errno = old_errno;

2329

return ret_errno;

2330

}

2331

2332

if(quit_now){

2333

ret = close(sd);

2334

if(ret == -1){

2335

perror_plus("close");

2336

}

2337

errno = old_errno;

2338

return EINTR;

2339

}

2340

2341

if(debug){

2342

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

2343

interface);

2344

}

2345

2346

/* Raise privileges */

2347

ret_errno = raise_privileges();

2348

if(ret_errno != 0){

2349

errno = ret_errno;

2350

perror_plus("Failed to raise privileges");

2351

}

2352

2353

#ifdef __linux__

2354

int ret_linux;

2355

bool restore_loglevel = false;

2356

if(ret_errno == 0){

2357

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2358

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

2359

ret_linux = klogctl(8, NULL, 5);

2360

if(ret_linux == -1){

2361

perror_plus("klogctl");

2362

} else {

2363

restore_loglevel = true;

2364

}

2365

}

2366

#endif /* __linux__ */

2367

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

2368

ioctl_errno = errno;

2369

#ifdef __linux__

2370

if(restore_loglevel){

2371

ret_linux = klogctl(7, NULL, 0);

2372

if(ret_linux == -1){

2373

perror_plus("klogctl");

2374

}

2375

}

2376

#endif /* __linux__ */

2377

2378

/* If raise_privileges() succeeded above */

2379

if(ret_errno == 0){

2380

/* Lower privileges */

2381

ret_errno = lower_privileges();

2382

if(ret_errno != 0){

2383

errno = ret_errno;

2384

perror_plus("Failed to lower privileges");

2385

}

2386

}

2387

2388

/* Close the socket */

2389

ret = close(sd);

2390

if(ret == -1){

2391

perror_plus("close");

2392

}

2393

2394

if(ret_setflags == -1){

2395

errno = ioctl_errno;

2396

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2397

errno = old_errno;

2398

return ioctl_errno;

2399

}

2400

} else if(debug){

2401

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

2402

interface);

2403

}

2404

2405

/* Sleep checking until interface is running.

2406

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

2407

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

2408

if(interface_is_running(interface)){

2409

break;

2410

}

2411

struct timespec sleeptime = { .tv_nsec = 250000000 };

2412

ret = nanosleep(&sleeptime, NULL);

2413

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

2414

perror_plus("nanosleep");

2415

}

2416

}

2417

2418

errno = old_errno;

2419

return 0;

2420

}

2421

2422

__attribute__((nonnull, warn_unused_result))

2423

int take_down_interface(const char *const interface){

2424

int old_errno = errno;

2425

struct ifreq network;

2426

unsigned int if_index = if_nametoindex(interface);

2427

if(if_index == 0){

2428

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

2429

errno = old_errno;

2430

return ENXIO;

2431

}

2432

if(interface_is_up(interface)){

2433

int ret_errno = 0;

2434

int ioctl_errno = 0;

2435

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

2436

ret_errno = errno;

2437

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

2438

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

2439

errno = old_errno;

2440

return ret_errno;

2441

}

2442

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

2443

2444

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

2445

if(sd == -1){

2446

ret_errno = errno;

2447

perror_plus("socket");

2448

errno = old_errno;

2449

return ret_errno;

2450

}

2451

2452

if(debug){

2453

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

2454

interface);

2455

}

2456

2457

/* Raise privileges */

2458

ret_errno = raise_privileges();

2459

if(ret_errno != 0){

2460

errno = ret_errno;

2461

perror_plus("Failed to raise privileges");

2462

}

2463

2464

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

2465

ioctl_errno = errno;

2466

2467

/* If raise_privileges() succeeded above */

2468

if(ret_errno == 0){

2469

/* Lower privileges */

2470

ret_errno = lower_privileges();

2471

if(ret_errno != 0){

2472

errno = ret_errno;

2473

perror_plus("Failed to lower privileges");

2474

}

2475

}

2476

2477

/* Close the socket */

2478

int ret = close(sd);

2479

if(ret == -1){

2480

perror_plus("close");

2481

}

2482

2483

if(ret_setflags == -1){

2484

errno = ioctl_errno;

2485

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2486

errno = old_errno;

2487

return ioctl_errno;

2488

}

2489

} else if(debug){

2490

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

2491

interface);

2492

}

2493

2494

errno = old_errno;

2495

return 0;

1021

2496

}

1022

2497

1023

2498

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

2499

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

2500

#if GNUTLS_VERSION_NUMBER >= 0x030606

2501

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

2502

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

2503

":%PROFILE_ULTRA",

2504

#elif GNUTLS_VERSION_NUMBER < 0x030600

2505

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

2506

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

2507

#else

2508

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

2509

#endif

2510

.current_server = NULL, .interfaces = NULL,

2511

.interfaces_size = 0 };

1024

2512

AvahiSServiceBrowser *sb = NULL;

1025

int error;

2513

error_t ret_errno;

1026

2514

int ret;

1027

2515

intmax_t tmpmax;

1028

2516

char *tmp;

1029

2517

int exitcode = EXIT_SUCCESS;

1030

const char *interface = "eth0";

1031

struct ifreq network;

1032

int sd = -1;

1033

bool take_down_interface = false;

1034

uid_t uid;

1035

gid_t gid;

1036

char *connect_to = NULL;

1037

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

1038

bool tempdir_created = false;

2518

char *interfaces_to_take_down = NULL;

2519

size_t interfaces_to_take_down_size = 0;

2520

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

2521

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

2522

char *tempdir = NULL;

1039

2523

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1040

2524

const char *seckey = PATHDIR "/" SECKEY;

1041

2525

const char *pubkey = PATHDIR "/" PUBKEY;

2526

#if GNUTLS_VERSION_NUMBER >= 0x030606

2527

const char *tls_privkey = PATHDIR "/" TLS_PRIVKEY;

2528

const char *tls_pubkey = PATHDIR "/" TLS_PUBKEY;

2529

#endif

2530

const char *dh_params_file = NULL;

2531

char *interfaces_hooks = NULL;

1042

2532

1043

2533

bool gnutls_initialized = false;

1044

2534

bool gpgme_initialized = false;

1045

2535

float delay = 2.5f;

2536

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

2537

retrying the same server again */

1046

2538

1047

2539

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1048

2540

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1054

2546

errno = 0;

1055

2547

ret = setgid(gid);

1056

2548

if(ret == -1){

1057

perror("setgid");

2549

perror_plus("setgid");

1058

2550

}

1059

2551

1060

2552

/* Lower user privileges (temporarily) */

1061

2553

errno = 0;

1062

2554

ret = seteuid(uid);

1063

2555

if(ret == -1){

1064

perror("seteuid");

2556

perror_plus("seteuid");

1065

2557

}

1066

2558

1067

2559

if(quit_now){

1088

2580

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

1089

2581

.arg = "FILE",

1090

2582

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

1091

.group = 2 },

2583

.group = 1 },

2584

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

2585

.arg = "FILE",

2586

#if GNUTLS_VERSION_NUMBER >= 0x030606

2587

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

2588

#else

2589

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

2590

#endif

2591

.group = 1 },

2592

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

2593

.arg = "FILE",

2594

#if GNUTLS_VERSION_NUMBER >= 0x030606

2595

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

2596

#else

2597

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

2598

#endif

2599

.group = 1 },

1092

2600

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

1093

2601

.arg = "BITS",

1094

2602

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

1095

2603

" Diffie-Hellman key exchange",

1096

2604

.group = 2 },

2605

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

2606

.arg = "FILE",

2607

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

2608

" for the Diffie-Hellman key exchange",

2609

.group = 2 },

1097

2610

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

1098

2611

.arg = "STRING",

1099

2612

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

1102

2615

.arg = "SECONDS",

1103

2616

.doc = "Maximum delay to wait for interface startup",

1104

2617

.group = 2 },

2618

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

2619

.arg = "SECONDS",

2620

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

2621

.group = 2 },

2622

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

2623

.arg = "DIR",

2624

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

2625

.group = 2 },

1105

2626

/*

1106

2627

* These reproduce what we would get without ARGP_NO_HELP

1107

2628

*/

1125

2646

connect_to = arg;

1126

2647

break;

1127

2648

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

1128

interface = arg;

2649

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

2650

arg, (int)',');

2651

if(ret_errno != 0){

2652

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

2653

}

1129

2654

break;

1130

2655

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

1131

2656

seckey = arg;

1133

2658

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

1134

2659

pubkey = arg;

1135

2660

break;

2661

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

2662

#if GNUTLS_VERSION_NUMBER >= 0x030606

2663

tls_privkey = arg;

2664

#endif

2665

break;

2666

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

2667

#if GNUTLS_VERSION_NUMBER >= 0x030606

2668

tls_pubkey = arg;

2669

#endif

2670

break;

1136

2671

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

1137

2672

errno = 0;

1138

2673

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

1142

2677

}

1143

2678

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

1144

2679

break;

2680

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

2681

dh_params_file = arg;

2682

break;

1145

2683

case 130: /* --priority */

1146

2684

mc.priority = arg;

1147

2685

break;

1151

2689

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

1152

2690

argp_error(state, "Bad delay");

1153

2691

}

2692

case 132: /* --retry */

2693

errno = 0;

2694

retry_interval = strtod(arg, &tmp);

2695

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

2696

or (retry_interval * 1000) > INT_MAX

2697

or retry_interval < 0){

2698

argp_error(state, "Bad retry interval");

2699

}

2700

break;

2701

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

2702

hookdir = arg;

1154

2703

break;

1155

2704

/*

1156

2705

* These reproduce what we would get without ARGP_NO_HELP

1159

2708

argp_state_help(state, state->out_stream,

1160

2709

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

1161

2710

& ~(unsigned int)ARGP_HELP_EXIT_OK);

2711

__builtin_unreachable();

1162

2712

case -3: /* --usage */

1163

2713

argp_state_help(state, state->out_stream,

1164

2714

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2715

__builtin_unreachable();

1165

2716

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

1166

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

2717

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

1167

2718

exit(argp_err_exit_status);

1168

2719

break;

1169

2720

default:

1176

2727

.args_doc = "",

1177

2728

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

1178

2729

" passwords from a Mandos server" };

1179

ret = argp_parse(&argp, argc, argv,

1180

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1181

switch(ret){

2730

ret_errno = argp_parse(&argp, argc, argv,

2731

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2732

switch(ret_errno){

1182

2733

case 0:

1183

2734

break;

1184

2735

case ENOMEM:

1185

2736

default:

1186

errno = ret;

1187

perror("argp_parse");

2737

errno = ret_errno;

2738

perror_plus("argp_parse");

1188

2739

exitcode = EX_OSERR;

1189

2740

goto end;

1190

2741

case EINVAL:

1193

2744

}

1194

2745

}

1195

2746

2747

{

2748

/* Re-raise privileges */

2749

ret = raise_privileges();

2750

if(ret != 0){

2751

errno = ret;

2752

perror_plus("Failed to raise privileges");

2753

} else {

2754

struct stat st;

2755

2756

/* Work around Debian bug #633582:

2757

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

2758

2759

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

2760

int seckey_fd = open(seckey, O_RDONLY);

2761

if(seckey_fd == -1){

2762

perror_plus("open");

2763

} else {

2764

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

2765

if(ret == -1){

2766

perror_plus("fstat");

2767

} else {

2768

if(S_ISREG(st.st_mode)

2769

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

2770

ret = fchown(seckey_fd, uid, gid);

2771

if(ret == -1){

2772

perror_plus("fchown");

2773

}

2774

}

2775

}

2776

close(seckey_fd);

2777

}

2778

}

2779

2780

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

2781

int pubkey_fd = open(pubkey, O_RDONLY);

2782

if(pubkey_fd == -1){

2783

perror_plus("open");

2784

} else {

2785

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

2786

if(ret == -1){

2787

perror_plus("fstat");

2788

} else {

2789

if(S_ISREG(st.st_mode)

2790

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

2791

ret = fchown(pubkey_fd, uid, gid);

2792

if(ret == -1){

2793

perror_plus("fchown");

2794

}

2795

}

2796

}

2797

close(pubkey_fd);

2798

}

2799

}

2800

2801

if(dh_params_file != NULL

2802

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

2803

int dhparams_fd = open(dh_params_file, O_RDONLY);

2804

if(dhparams_fd == -1){

2805

perror_plus("open");

2806

} else {

2807

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

2808

if(ret == -1){

2809

perror_plus("fstat");

2810

} else {

2811

if(S_ISREG(st.st_mode)

2812

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

2813

ret = fchown(dhparams_fd, uid, gid);

2814

if(ret == -1){

2815

perror_plus("fchown");

2816

}

2817

}

2818

}

2819

close(dhparams_fd);

2820

}

2821

}

2822

2823

/* Work around Debian bug #981302

2824

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

2825

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

2826

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

2827

if(ret == -1){

2828

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

2829

}

2830

}

2831

2832

/* Lower privileges */

2833

ret = lower_privileges();

2834

if(ret != 0){

2835

errno = ret;

2836

perror_plus("Failed to lower privileges");

2837

}

2838

}

2839

}

2840

2841

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

2842

{

2843

char *interface = NULL;

2844

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

2845

interface))){

2846

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

2847

and if_nametoindex(interface) == 0){

2848

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

2849

fprintf_plus(stderr, "Not using nonexisting interface"

2850

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

2851

}

2852

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

2853

interface = NULL;

2854

}

2855

}

2856

}

2857

2858

/* Run network hooks */

2859

{

2860

if(mc.interfaces != NULL){

2861

interfaces_hooks = malloc(mc.interfaces_size);

2862

if(interfaces_hooks == NULL){

2863

perror_plus("malloc");

2864

goto end;

2865

}

2866

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

2867

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

2868

}

2869

run_network_hooks("start", interfaces_hooks != NULL ?

2870

interfaces_hooks : "", delay);

2871

}

2872

1196

2873

if(not debug){

1197

2874

avahi_set_log_function(empty_log);

1198

2875

}

1201

2878

from the signal handler */

1202

2879

/* Initialize the pseudo-RNG for Avahi */

1203

2880

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

1204

mc.simple_poll = avahi_simple_poll_new();

1205

if(mc.simple_poll == NULL){

1206

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

2881

simple_poll = avahi_simple_poll_new();

2882

if(simple_poll == NULL){

2883

fprintf_plus(stderr,

2884

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

1207

2885

exitcode = EX_UNAVAILABLE;

1208

2886

goto end;

1209

2887

}

1211

2889

sigemptyset(&sigterm_action.sa_mask);

1212

2890

ret = sigaddset(&sigterm_action.sa_mask, SIGINT);

1213

2891

if(ret == -1){

1214

perror("sigaddset");

2892

perror_plus("sigaddset");

1215

2893

exitcode = EX_OSERR;

1216

2894

goto end;

1217

2895

}

1218

2896

ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);

1219

2897

if(ret == -1){

1220

perror("sigaddset");

2898

perror_plus("sigaddset");

1221

2899

exitcode = EX_OSERR;

1222

2900

goto end;

1223

2901

}

1224

2902

ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);

1225

2903

if(ret == -1){

1226

perror("sigaddset");

2904

perror_plus("sigaddset");

1227

2905

exitcode = EX_OSERR;

1228

2906

goto end;

1229

2907

}

1233

2911

*/

1234

2912

ret = sigaction(SIGINT, NULL, &old_sigterm_action);

1235

2913

if(ret == -1){

1236

perror("sigaction");

2914

perror_plus("sigaction");

1237

2915

return EX_OSERR;

1238

2916

}

1239

2917

if(old_sigterm_action.sa_handler != SIG_IGN){

1240

2918

ret = sigaction(SIGINT, &sigterm_action, NULL);

1241

2919

if(ret == -1){

1242

perror("sigaction");

2920

perror_plus("sigaction");

1243

2921

exitcode = EX_OSERR;

1244

2922

goto end;

1245

2923

}

1246

2924

}

1247

2925

ret = sigaction(SIGHUP, NULL, &old_sigterm_action);

1248

2926

if(ret == -1){

1249

perror("sigaction");

2927

perror_plus("sigaction");

1250

2928

return EX_OSERR;

1251

2929

}

1252

2930

if(old_sigterm_action.sa_handler != SIG_IGN){

1253

2931

ret = sigaction(SIGHUP, &sigterm_action, NULL);

1254

2932

if(ret == -1){

1255

perror("sigaction");

2933

perror_plus("sigaction");

1256

2934

exitcode = EX_OSERR;

1257

2935

goto end;

1258

2936

}

1259

2937

}

1260

2938

ret = sigaction(SIGTERM, NULL, &old_sigterm_action);

1261

2939

if(ret == -1){

1262

perror("sigaction");

2940

perror_plus("sigaction");

1263

2941

return EX_OSERR;

1264

2942

}

1265

2943

if(old_sigterm_action.sa_handler != SIG_IGN){

1266

2944

ret = sigaction(SIGTERM, &sigterm_action, NULL);

1267

2945

if(ret == -1){

1268

perror("sigaction");

1269

exitcode = EX_OSERR;

1270

goto end;

1271

}

1272

}

1273

1274

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

1275

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

1276

if_index = (AvahiIfIndex) if_nametoindex(interface);

1277

if(if_index == 0){

1278

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

1279

exitcode = EX_UNAVAILABLE;

1280

goto end;

1281

}

1282

1283

if(quit_now){

1284

goto end;

1285

}

1286

1287

/* Re-raise priviliges */

1288

errno = 0;

1289

ret = seteuid(0);

1290

if(ret == -1){

1291

perror("seteuid");

1292

}

1293

1294

#ifdef __linux__

1295

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1296

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

1297

ret = klogctl(8, NULL, 5);

1298

bool restore_loglevel = true;

1299

if(ret == -1){

1300

restore_loglevel = false;

1301

perror("klogctl");

1302

}

1303

#endif /* __linux__ */

1304

1305

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1306

if(sd < 0){

1307

perror("socket");

1308

exitcode = EX_OSERR;

1309

#ifdef __linux__

1310

if(restore_loglevel){

1311

ret = klogctl(7, NULL, 0);

1312

if(ret == -1){

1313

perror("klogctl");

1314

}

1315

}

1316

#endif /* __linux__ */

1317

/* Lower privileges */

1318

errno = 0;

1319

ret = seteuid(uid);

1320

if(ret == -1){

1321

perror("seteuid");

1322

}

1323

goto end;

1324

}

1325

strcpy(network.ifr_name, interface);

1326

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

1327

if(ret == -1){

1328

perror("ioctl SIOCGIFFLAGS");

1329

#ifdef __linux__

1330

if(restore_loglevel){

1331

ret = klogctl(7, NULL, 0);

1332

if(ret == -1){

1333

perror("klogctl");

1334

}

1335

}

1336

#endif /* __linux__ */

1337

exitcode = EX_OSERR;

1338

/* Lower privileges */

1339

errno = 0;

1340

ret = seteuid(uid);

1341

if(ret == -1){

1342

perror("seteuid");

1343

}

1344

goto end;

1345

}

1346

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

1347

network.ifr_flags |= IFF_UP;

1348

take_down_interface = true;

1349

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

1350

if(ret == -1){

1351

take_down_interface = false;

1352

perror("ioctl SIOCSIFFLAGS");

1353

exitcode = EX_OSERR;

1354

#ifdef __linux__

1355

if(restore_loglevel){

1356

ret = klogctl(7, NULL, 0);

1357

if(ret == -1){

1358

perror("klogctl");

2946

perror_plus("sigaction");

2947

exitcode = EX_OSERR;

2948

goto end;

2949

}

2950

}

2951

2952

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

2953

if(mc.interfaces == NULL){

2954

struct dirent **direntries = NULL;

2955

/* Look for any good interfaces */

2956

ret = scandir(sys_class_net, &direntries, good_interface,

2957

alphasort);

2958

if(ret >= 1){

2959

/* Add all found interfaces to interfaces list */

2960

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

2961

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

2962

direntries[i]->d_name);

2963

if(ret_errno != 0){

2964

errno = ret_errno;

2965

perror_plus("argz_add");

2966

free(direntries[i]);

2967

continue;

2968

}

2969

if(debug){

2970

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

2971

direntries[i]->d_name);

2972

}

2973

free(direntries[i]);

2974

}

2975

free(direntries);

2976

} else {

2977

if(ret == 0){

2978

free(direntries);

2979

}

2980

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

2981

exitcode = EXIT_FAILURE;

2982

goto end;

2983

}

2984

}

2985

2986

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

2987

{

2988

char *interface = NULL;

2989

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

2990

interface))){

2991

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

2992

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

2993

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

2994

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

2995

interface);

2996

interface = NULL;

2997

while((interface = argz_next(mc.interfaces,

2998

mc.interfaces_size, interface))){

2999

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

3000

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

3001

interface);

3002

interface = NULL;

1359

3003

}

1360

3004

}

1361

#endif /* __linux__ */

1362

/* Lower privileges */

1363

errno = 0;

1364

ret = seteuid(uid);

1365

if(ret == -1){

1366

perror("seteuid");

1367

}

1368

goto end;

1369

}

1370

}

1371

/* sleep checking until interface is running */

1372

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

1373

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

1374

if(ret == -1){

1375

perror("ioctl SIOCGIFFLAGS");

1376

} else if(network.ifr_flags & IFF_RUNNING){

1377

3005

break;

1378

3006

}

1379

struct timespec sleeptime = { .tv_nsec = 250000000 };

1380

ret = nanosleep(&sleeptime, NULL);

1381

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

1382

perror("nanosleep");

1383

}

1384

}

1385

if(not take_down_interface){

1386

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

1387

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

1388

if(ret == -1){

1389

perror("close");

1390

}

1391

}

1392

#ifdef __linux__

1393

if(restore_loglevel){

1394

/* Restores kernel loglevel to default */

1395

ret = klogctl(7, NULL, 0);

1396

if(ret == -1){

1397

perror("klogctl");

1398

}

1399

}

1400

#endif /* __linux__ */

1401

/* Lower privileges */

1402

errno = 0;

1403

if(take_down_interface){

1404

/* Lower privileges */

1405

ret = seteuid(uid);

1406

if(ret == -1){

1407

perror("seteuid");

1408

}

1409

} else {

1410

/* Lower privileges permanently */

1411

ret = setuid(uid);

1412

if(ret == -1){

1413

perror("setuid");

1414

}

1415

}

3007

bool interface_was_up = interface_is_up(interface);

3008

errno = bring_up_interface(interface, delay);

3009

if(not interface_was_up){

3010

if(errno != 0){

3011

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

3012

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

3013

} else {

3014

errno = argz_add(&interfaces_to_take_down,

3015

&interfaces_to_take_down_size,

3016

interface);

3017

if(errno != 0){

3018

perror_plus("argz_add");

3019

}

3020

}

3021

}

3022

}

3023

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

3024

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

3025

}

3026

}

3027

3028

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

3029

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

3030

if(debug){

3031

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

3032

mc.interfaces);

3033

}

3034

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

1416

3035

}

1417

3036

1418

3037

if(quit_now){

1419

3038

goto end;

1420

3039

}

1421

3040

1422

ret = init_gnutls_global(pubkey, seckey);

3041

#if GNUTLS_VERSION_NUMBER >= 0x030606

3042

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

3043

#elif GNUTLS_VERSION_NUMBER < 0x030600

3044

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

3045

#else

3046

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

3047

#endif

1423

3048

if(ret == -1){

1424

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

3049

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

1425

3050

exitcode = EX_UNAVAILABLE;

1426

3051

goto end;

1427

3052

} else {

1432

3057

goto end;

1433

3058

}

1434

3059

1435

tempdir_created = true;

1436

if(mkdtemp(tempdir) == NULL){

1437

tempdir_created = false;

1438

perror("mkdtemp");

3060

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

3061

tempdir = mkdtemp(run_tempdir);

3062

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

3063

if(debug){

3064

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

3065

run_tempdir, old_tempdir);

3066

}

3067

tempdir = mkdtemp(old_tempdir);

3068

}

3069

if(tempdir == NULL){

3070

perror_plus("mkdtemp");

1439

3071

goto end;

1440

3072

}

1441

3073

1443

3075

goto end;

1444

3076

}

1445

3077

1446

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

1447

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

3078

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

3079

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

1448

3080

exitcode = EX_UNAVAILABLE;

1449

3081

goto end;

1450

3082

} else {

1459

3091

/* Connect directly, do not use Zeroconf */

1460

3092

/* (Mainly meant for debugging) */

1461

3093

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

3094

1462

3095

if(address == NULL){

1463

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

3096

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

1464

3097

exitcode = EX_USAGE;

1465

3098

goto end;

1466

3099

}

1469

3102

goto end;

1470

3103

}

1471

3104

1472

uint16_t port;

3105

in_port_t port;

1473

3106

errno = 0;

1474

3107

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

1475

3108

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

1476

or tmpmax != (uint16_t)tmpmax){

1477

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

3109

or tmpmax != (in_port_t)tmpmax){

3110

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

1478

3111

exitcode = EX_USAGE;

1479

3112

goto end;

1480

3113

}

1481

3114

1482

3115

if(quit_now){

1483

3116

goto end;

1484

3117

}

1485

3118

1486

port = (uint16_t)tmpmax;

3119

port = (in_port_t)tmpmax;

1487

3120

*address = '\0';

1488

address = connect_to;

1489

3121

/* Colon in address indicates IPv6 */

1490

3122

int af;

1491

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

3123

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

1492

3124

af = AF_INET6;

3125

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

3126

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

3127

{

3128

connect_to++;

3129

address[-1] = '\0';

3130

}

1493

3131

} else {

1494

3132

af = AF_INET;

1495

3133

}

3134

address = connect_to;

1496

3135

1497

3136

if(quit_now){

1498

3137

goto end;

1499

3138

}

1500

3139

1501

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

1502

if(ret < 0){

1503

switch(errno){

1504

case ENETUNREACH:

1505

case EHOSTDOWN:

1506

case EHOSTUNREACH:

1507

exitcode = EX_NOHOST;

1508

break;

1509

case EINVAL:

1510

exitcode = EX_USAGE;

1511

break;

1512

case EIO:

1513

exitcode = EX_IOERR;

1514

break;

1515

case EPROTO:

1516

exitcode = EX_PROTOCOL;

1517

break;

1518

default:

1519

exitcode = EX_OSERR;

1520

break;

1521

}

1522

} else {

3140

while(not quit_now){

3141

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

3142

&mc);

3143

if(quit_now or ret == 0){

3144

break;

3145

}

3146

if(debug){

3147

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

3148

(int)retry_interval);

3149

}

3150

sleep((unsigned int)retry_interval);

3151

}

3152

3153

if(not quit_now){

1523

3154

exitcode = EXIT_SUCCESS;

1524

3155

}

3156

1525

3157

goto end;

1526

3158

}

1527

3159

1539

3171

config.publish_domain = 0;

1540

3172

1541

3173

/* Allocate a new server */

1542

mc.server = avahi_server_new(avahi_simple_poll_get

1543

(mc.simple_poll), &config, NULL,

1544

NULL, &error);

3174

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

3175

&config, NULL, NULL, &ret);

1545

3176

1546

3177

/* Free the Avahi configuration data */

1547

3178

avahi_server_config_free(&config);

1549

3180

1550

3181

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

1551

3182

if(mc.server == NULL){

1552

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

1553

avahi_strerror(error));

3183

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

3184

avahi_strerror(ret));

1554

3185

exitcode = EX_UNAVAILABLE;

1555

3186

goto end;

1556

3187

}

1562

3193

/* Create the Avahi service browser */

1563

3194

sb = avahi_s_service_browser_new(mc.server, if_index,

1564

3195

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1565

NULL, 0, browse_callback, NULL);

3196

NULL, 0, browse_callback,

3197

(void *)&mc);

1566

3198

if(sb == NULL){

1567

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

1568

avahi_strerror(avahi_server_errno(mc.server)));

3199

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

3200

avahi_strerror(avahi_server_errno(mc.server)));

1569

3201

exitcode = EX_UNAVAILABLE;

1570

3202

goto end;

1571

3203

}

1577

3209

/* Run the main loop */

1578

3210

1579

3211

if(debug){

1580

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

3212

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

1581

3213

}

1582

3214

1583

avahi_simple_poll_loop(mc.simple_poll);

3215

ret = avahi_loop_with_timeout(simple_poll,

3216

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

3217

if(debug){

3218

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

3219

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

3220

}

1584

3221

1585

3222

end:

1586

3223

1587

3224

if(debug){

1588

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

3225

if(signal_received){

3226

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

3227

argv[0], signal_received,

3228

strsignal(signal_received));

3229

} else {

3230

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

3231

}

1589

3232

}

1590

3233

1591

3234

/* Cleanup things */

3235

free(mc.interfaces);

3236

1592

3237

if(sb != NULL)

1593

3238

avahi_s_service_browser_free(sb);

1594

3239

1595

3240

if(mc.server != NULL)

1596

3241

avahi_server_free(mc.server);

1597

3242

1598

if(mc.simple_poll != NULL)

1599

avahi_simple_poll_free(mc.simple_poll);

3243

if(simple_poll != NULL)

3244

avahi_simple_poll_free(simple_poll);

1600

3245

1601

3246

if(gnutls_initialized){

1602

3247

gnutls_certificate_free_credentials(mc.cred);

1603

gnutls_global_deinit();

1604

3248

gnutls_dh_params_deinit(mc.dh_params);

1605

3249

}

1606

3250

1608

3252

gpgme_release(mc.ctx);

1609

3253

}

1610

3254

1611

/* Take down the network interface */

1612

if(take_down_interface){

1613

/* Re-raise priviliges */

1614

errno = 0;

1615

ret = seteuid(0);

1616

if(ret == -1){

1617

perror("seteuid");

1618

}

1619

if(geteuid() == 0){

1620

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

1621

if(ret == -1){

1622

perror("ioctl SIOCGIFFLAGS");

1623

} else if(network.ifr_flags & IFF_UP) {

1624

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

1625

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

1626

if(ret == -1){

1627

perror("ioctl SIOCSIFFLAGS");

1628

}

1629

}

1630

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

1631

if(ret == -1){

1632

perror("close");

1633

}

1634

/* Lower privileges permanently */

1635

errno = 0;

1636

ret = setuid(uid);

1637

if(ret == -1){

1638

perror("setuid");

1639

}

1640

}

1641

}

1642

1643

/* Removes the temp directory used by GPGME */

1644

if(tempdir_created){

1645

DIR *d;

1646

struct dirent *direntry;

1647

d = opendir(tempdir);

1648

if(d == NULL){

1649

if(errno != ENOENT){

1650

perror("opendir");

1651

}

1652

} else {

1653

while(true){

1654

direntry = readdir(d);

1655

if(direntry == NULL){

1656

break;

1657

}

1658

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

1659

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

1660

and (direntry->d_name[1] == '\0'

1661

or (direntry->d_name[1] == '.'

1662

and direntry->d_name[2] == '\0'))){

1663

continue;

1664

}

1665

char *fullname = NULL;

1666

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

1667

direntry->d_name);

1668

if(ret < 0){

1669

perror("asprintf");

1670

continue;

1671

}

1672

ret = remove(fullname);

1673

if(ret == -1){

1674

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

1675

strerror(errno));

1676

}

1677

free(fullname);

1678

}

1679

closedir(d);

1680

}

1681

ret = rmdir(tempdir);

1682

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

1683

perror("rmdir");

1684

}

3255

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

3256

has seen */

3257

if(mc.current_server != NULL){

3258

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

3259

while(mc.current_server != NULL){

3260

server *next = mc.current_server->next;

3261

#ifdef __GNUC__

3262

#pragma GCC diagnostic push

3263

#pragma GCC diagnostic ignored "-Wcast-qual"

3264

#endif

3265

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

3266

#ifdef __GNUC__

3267

#pragma GCC diagnostic pop

3268

#endif

3269

free(mc.current_server);

3270

mc.current_server = next;

3271

}

3272

}

3273

3274

/* Re-raise privileges */

3275

{

3276

ret = raise_privileges();

3277

if(ret != 0){

3278

errno = ret;

3279

perror_plus("Failed to raise privileges");

3280

} else {

3281

3282

/* Run network hooks */

3283

run_network_hooks("stop", interfaces_hooks != NULL ?

3284

interfaces_hooks : "", delay);

3285

3286

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

3287

{

3288

char *interface = NULL;

3289

while((interface = argz_next(interfaces_to_take_down,

3290

interfaces_to_take_down_size,

3291

interface))){

3292

ret = take_down_interface(interface);

3293

if(ret != 0){

3294

errno = ret;

3295

perror_plus("Failed to take down interface");

3296

}

3297

}

3298

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

3299

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

3300

" down\n");

3301

}

3302

}

3303

}

3304

3305

ret = lower_privileges_permanently();

3306

if(ret != 0){

3307

errno = ret;

3308

perror_plus("Failed to lower privileges permanently");

3309

}

3310

}

3311

3312

free(interfaces_to_take_down);

3313

free(interfaces_hooks);

3314

3315

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

3316

uintmax_t level){

3317

struct dirent **direntries = NULL;

3318

int dret;

3319

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

3320

O_RDONLY

3321

| O_NOFOLLOW

3322

| O_DIRECTORY

3323

| O_PATH));

3324

if(dir_fd == -1){

3325

perror_plus("open");

3326

return;

3327

}

3328

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

3329

notdotentries, alphasort);

3330

if(numentries >= 0){

3331

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

3332

if(debug){

3333

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

3334

dirname, direntries[i]->d_name);

3335

}

3336

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

3337

if(dret == -1){

3338

if(errno == EISDIR){

3339

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

3340

AT_REMOVEDIR);

3341

}

3342

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

3343

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

3344

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

3345

/* Recurse only in this special case */

3346

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

3347

dret = 0;

3348

}

3349

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

3350

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

3351

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

3352

}

3353

}

3354

free(direntries[i]);

3355

}

3356

3357

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

3358

free(direntries);

3359

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3360

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

3361

perror_plus("rmdir");

3362

}

3363

} else {

3364

perror_plus("scandirat");

3365

}

3366

close(dir_fd);

3367

}

3368

3369

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

3370

if(tempdir != NULL){

3371

clean_dir_at(-1, tempdir, 0);

1685

3372

}

1686

3373

1687

3374

if(quit_now){

1691

3378

&old_sigterm_action,

1692

3379

NULL));

1693

3380

if(ret == -1){

1694

perror("sigaction");

3381

perror_plus("sigaction");

1695

3382

}

1696

3383

do {

1697

3384

ret = raise(signal_received);

1698

3385

} while(ret != 0 and errno == EINTR);

1699

3386

if(ret != 0){

1700

perror("raise");

3387

perror_plus("raise");

1701

3388

abort();

1702

3389

}

1703

3390

TEMP_FAILURE_RETRY(pause());