/mandos/release : revision 237.7.147

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

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*

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* Everything else is

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*

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* This file is part of Mandos.

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*

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

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

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

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* (at your option) any later version.

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*

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

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*

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

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

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

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

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*

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

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* WITHOUT ANY WARRANTY; without even the implied warranty of

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

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* General Public License for more details.

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*

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

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

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* along with this program. If not, see

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

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*

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

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*/

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

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#ifndef _LARGEFILE_SOURCE

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#define _LARGEFILE_SOURCE

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#endif /* not _LARGEFILE_SOURCE */

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#endif

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#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

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#endif /* not _FILE_OFFSET_BITS */

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#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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#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, intptr_t */

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

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

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strtof(), abort() */

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

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#include <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 <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(), S_ISREG */

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

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inet_pton(), connect() */

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

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

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*/

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

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strtoimax() */

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

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program_invocation_short_name */

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

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

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SIOCSIFFLAGS, if_indextoname(),

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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(), _exit() */

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

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

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

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argp_state, struct argp,

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

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WEXITSTATUS(), WTERMSIG() */

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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() */

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

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argz_delete(), argz_append(),

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argz_stringify(), argz_add(),

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argz_count() */

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#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: gnutls_*, GNUTLS_* */

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#if GNUTLS_VERSION_NUMBER < 0x030600

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functions:

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gnutls_*

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init_gnutls_session(),

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GNUTLS_* */

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#include <gnutls/openpgp.h>

159

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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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functions:

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gpgme_*, GPG_ERR_NO_*,

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GPGME_IMPORT_*

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GPGME_PROTOCOL_OpenPGP */

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gpgme_*

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GPGME_PROTOCOL_OpenPGP,

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GPG_ERR_NO_* */

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#define BUFFER_SIZE 256

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128

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

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#define SECKEY "seckey.txt"

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#define PUBKEY "pubkey.txt"

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#define TLS_PRIVKEY "tls-privkey.pem"

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#define TLS_PUBKEY "tls-pubkey.pem"

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

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bool debug = false;

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

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char *connect_to = NULL;

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const char *hookdir = HOOKDIR;

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int hookdir_fd = -1;

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uid_t uid = 65534;

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gid_t gid = 65534;

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143

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

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typedef struct {

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AvahiSimplePoll *simple_poll;

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AvahiServer *server;

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gnutls_certificate_credentials_t cred;

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unsigned int dh_bits;

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const char *priority;

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gpgme_ctx_t ctx;

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server *current_server;

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char *interfaces;

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size_t interfaces_size;

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} mandos_context;

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/* global so signal handler can reach it*/

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AvahiSimplePoll *simple_poll;

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

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

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.dh_bits = 1024, .priority = "SECURE256"

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

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.current_server = NULL };

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sig_atomic_t quit_now = 0;

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int signal_received = 0;

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perror(print_text);

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}

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

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

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

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va_list ap;

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va_start (ap, format);

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

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program_invocation_short_name));

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

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

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}

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/*

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

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* "buffer_length" is how much is already used.

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*/

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__attribute__((nonnull, warn_unused_result))

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size_t incbuffer(char **buffer, size_t buffer_length,

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size_t buffer_capacity){

250

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if(buffer_length + BUFFER_SIZE > buffer_capacity){

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

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if(new_buf == NULL){

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int old_errno = errno;

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free(*buffer);

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errno = old_errno;

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*buffer = NULL;

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

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if(buffer == NULL){

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return 0;

258

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}

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*buffer = new_buf;

260

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buffer_capacity += BUFFER_SIZE;

261

208

}

262

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return buffer_capacity;

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}

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

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__attribute__((nonnull, warn_unused_result))

267

213

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

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int af, server **current_server){

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int af){

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int ret;

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

271

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if(new_server == NULL){

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.af = af };

279

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if(new_server->ip == NULL){

280

226

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

227

return false;

297

228

}

298

229

/* Special case of first server */

299

if(*current_server == NULL){

230

if (mc.current_server == NULL){

300

231

new_server->next = new_server;

301

232

new_server->prev = new_server;

302

*current_server = new_server;

233

mc.current_server = new_server;

234

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

303

235

} else {

304

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

305

new_server->next = *current_server;

306

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

236

new_server->next = mc.current_server;

237

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

307

238

new_server->prev->next = new_server;

308

(*current_server)->prev = new_server;

239

mc.current_server->prev = new_server;

240

}

241

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

242

if(ret == -1){

243

perror_plus("clock_gettime");

244

return false;

309

245

}

310

246

return true;

311

247

}

312

248

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

365

249

/*

366

250

* Initialize GPGME.

367

251

*/

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){

252

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

253

const char *tempdir){

373

254

gpgme_error_t rc;

374

255

gpgme_engine_info_t engine_info;

375

256

257

376

258

/*

377

259

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

378

260

*/

379

bool import_key(const char * const filename){

261

bool import_key(const char *filename){

380

262

int ret;

381

263

int fd;

382

264

gpgme_data_t pgp_data;

387

269

return false;

388

270

}

389

271

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

439

272

rc = gpgme_data_new_from_fd(&pgp_data, fd);

440

273

if(rc != GPG_ERR_NO_ERROR){

441

274

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

443

276

return false;

444

277

}

445

278

446

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

279

rc = gpgme_op_import(mc.ctx, pgp_data);

447

280

if(rc != GPG_ERR_NO_ERROR){

448

281

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

449

282

gpgme_strsource(rc), gpgme_strerror(rc));

450

283

return false;

451

284

}

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

}

527

285

528

ret = close(fd);

286

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

529

287

if(ret == -1){

530

288

perror_plus("close");

531

289

}

568

326

}

569

327

570

328

/* Create new GPGME "context" */

571

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

329

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

572

330

if(rc != GPG_ERR_NO_ERROR){

573

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

574

gpgme_strsource(rc), gpgme_strerror(rc));

331

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

332

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

333

gpgme_strerror(rc));

575

334

return false;

576

335

}

577

336

586

345

* Decrypt OpenPGP data.

587

346

* Returns -1 on error

588

347

*/

589

__attribute__((nonnull, warn_unused_result))

590

348

static ssize_t pgp_packet_decrypt(const char *cryptotext,

591

349

size_t crypto_size,

592

char **plaintext,

593

mandos_context *mc){

350

char **plaintext){

594

351

gpgme_data_t dh_crypto, dh_plain;

595

352

gpgme_error_t rc;

596

353

ssize_t ret;

613

370

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

614

371

rc = gpgme_data_new(&dh_plain);

615

372

if(rc != GPG_ERR_NO_ERROR){

616

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

373

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

374

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

617

375

gpgme_strsource(rc), gpgme_strerror(rc));

618

376

gpgme_data_release(dh_crypto);

619

377

return -1;

621

379

622

380

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

623

381

data buffer */

624

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

382

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

625

383

if(rc != GPG_ERR_NO_ERROR){

626

384

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

627

385

gpgme_strsource(rc), gpgme_strerror(rc));

628

386

plaintext_length = -1;

629

387

if(debug){

630

388

gpgme_decrypt_result_t result;

631

result = gpgme_op_decrypt_result(mc->ctx);

389

result = gpgme_op_decrypt_result(mc.ctx);

632

390

if(result == NULL){

633

391

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

634

392

} else {

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");

393

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

394

result->unsupported_algorithm);

395

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

396

result->wrong_key_usage);

641

397

if(result->file_name != NULL){

642

398

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

643

399

}

644

645

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

646

r = r->next){

400

gpgme_recipient_t recipient;

401

recipient = result->recipients;

402

while(recipient != NULL){

647

403

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);

404

gpgme_pubkey_algo_name

405

(recipient->pubkey_algo));

406

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

650

407

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

651

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

408

recipient->status == GPG_ERR_NO_SECKEY

409

? "No" : "Yes");

410

recipient = recipient->next;

652

411

}

653

412

}

654

413

}

710

469

return plaintext_length;

711

470

}

712

471

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){

472

static const char * safer_gnutls_strerror(int value){

722

473

const char *ret = gnutls_strerror(value);

723

return safe_string(ret);

474

if(ret == NULL)

475

ret = "(unknown)";

476

return ret;

724

477

}

725

478

726

479

/* GnuTLS log function callback */

727

__attribute__((nonnull))

728

480

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

729

481

const char* string){

730

482

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

731

483

}

732

484

733

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

734

485

static int init_gnutls_global(const char *pubkeyfilename,

735

const char *seckeyfilename,

736

const char *dhparamsfilename,

737

mandos_context *mc){

486

const char *seckeyfilename){

738

487

int ret;

739

488

740

489

if(debug){

741

490

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

742

491

}

743

492

493

ret = gnutls_global_init();

494

if(ret != GNUTLS_E_SUCCESS){

495

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

496

safer_gnutls_strerror(ret));

497

return -1;

498

}

499

744

500

if(debug){

745

501

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

746

502

* - GnuTLS manual

750

506

}

751

507

752

508

/* OpenPGP credentials */

753

ret = gnutls_certificate_allocate_credentials(&mc->cred);

509

ret = gnutls_certificate_allocate_credentials(&mc.cred);

754

510

if(ret != GNUTLS_E_SUCCESS){

755

511

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

756

512

safer_gnutls_strerror(ret));

513

gnutls_global_deinit();

757

514

return -1;

758

515

}

759

516

760

517

if(debug){

761

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

762

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

518

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

519

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

763

520

pubkeyfilename,

764

521

seckeyfilename);

765

522

}

766

523

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

780

524

ret = gnutls_certificate_set_openpgp_key_file

781

(mc->cred, pubkeyfilename, seckeyfilename,

525

(mc.cred, pubkeyfilename, seckeyfilename,

782

526

GNUTLS_OPENPGP_FMT_BASE64);

783

#else

784

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

785

#endif

786

527

if(ret != GNUTLS_E_SUCCESS){

787

528

fprintf_plus(stderr,

788

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

529

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

789

530

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

790

531

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

791

532

safer_gnutls_strerror(ret));

793

534

}

794

535

795

536

/* GnuTLS server initialization */

796

ret = gnutls_dh_params_init(&mc->dh_params);

537

ret = gnutls_dh_params_init(&mc.dh_params);

797

538

if(ret != GNUTLS_E_SUCCESS){

798

539

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

799

540

" initialization: %s\n",

800

541

safer_gnutls_strerror(ret));

801

542

goto globalfail;

802

543

}

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

}

544

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

545

if(ret != GNUTLS_E_SUCCESS){

546

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

547

safer_gnutls_strerror(ret));

548

goto globalfail;

549

}

550

551

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

985

552

986

553

return 0;

987

554

988

555

globalfail:

989

556

990

gnutls_certificate_free_credentials(mc->cred);

991

gnutls_dh_params_deinit(mc->dh_params);

557

gnutls_certificate_free_credentials(mc.cred);

558

gnutls_global_deinit();

559

gnutls_dh_params_deinit(mc.dh_params);

992

560

return -1;

993

561

}

994

562

995

__attribute__((nonnull, warn_unused_result))

996

static int init_gnutls_session(gnutls_session_t *session,

997

mandos_context *mc){

563

static int init_gnutls_session(gnutls_session_t *session){

998

564

int ret;

999

565

/* GnuTLS session creation */

1000

566

do {

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

));

567

ret = gnutls_init(session, GNUTLS_SERVER);

1009

568

if(quit_now){

1010

569

return -1;

1011

570

}

1019

578

{

1020

579

const char *err;

1021

580

do {

1022

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

581

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

1023

582

if(quit_now){

1024

583

gnutls_deinit(*session);

1025

584

return -1;

1036

595

1037

596

do {

1038

597

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

1039

mc->cred);

598

mc.cred);

1040

599

if(quit_now){

1041

600

gnutls_deinit(*session);

1042

601

return -1;

1052

611

/* ignore client certificate if any. */

1053

612

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

1054

613

614

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

615

1055

616

return 0;

1056

617

}

1057

618

1059

620

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

1060

621

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

1061

622

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

1235

623

/* Called when a Mandos server is found */

1236

__attribute__((nonnull, warn_unused_result))

1237

624

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

1238

625

AvahiIfIndex if_index,

1239

int af, mandos_context *mc){

626

int af){

1240

627

int ret, tcp_sd = -1;

1241

628

ssize_t sret;

1242

struct sockaddr_storage to;

629

union {

630

struct sockaddr_in in;

631

struct sockaddr_in6 in6;

632

} to;

1243

633

char *buffer = NULL;

1244

634

char *decrypted_buffer = NULL;

1245

635

size_t buffer_length = 0;

1248

638

int retval = -1;

1249

639

gnutls_session_t session;

1250

640

int pf; /* Protocol family */

1251

bool route_added = false;

1252

641

1253

642

errno = 0;

1254

643

1270

659

return -1;

1271

660

}

1272

661

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);

662

ret = init_gnutls_session(&session);

1307

663

if(ret != 0){

1308

664

return -1;

1309

665

}

1313

669

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

1314

670

}

1315

671

1316

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

672

tcp_sd = socket(pf, SOCK_STREAM, 0);

1317

673

if(tcp_sd < 0){

1318

674

int e = errno;

1319

675

perror_plus("socket");

1326

682

goto mandos_end;

1327

683

}

1328

684

685

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

1329

686

if(af == AF_INET6){

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);

687

to.in6.sin6_family = (sa_family_t)af;

688

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

1333

689

} else { /* IPv4 */

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);

690

to.in.sin_family = (sa_family_t)af;

691

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

1337

692

}

1338

693

if(ret < 0 ){

1339

694

int e = errno;

1348

703

goto mandos_end;

1349

704

}

1350

705

if(af == AF_INET6){

1351

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

1352

if(IN6_IS_ADDR_LINKLOCAL

1353

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

706

to.in6.sin6_port = htons(port);

707

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

708

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

709

-Wunreachable-code*/

1354

710

if(if_index == AVAHI_IF_UNSPEC){

1355

711

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

1356

712

" incomplete without a network interface\n");

1358

714

goto mandos_end;

1359

715

}

1360

716

/* Set the network interface number as scope */

1361

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

717

to.in6.sin6_scope_id = (uint32_t)if_index;

1362

718

}

1363

719

} else {

1364

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

720

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

721

-Wconversion and

722

-Wunreachable-code */

1365

723

}

1366

724

1367

725

if(quit_now){

1384

742

}

1385

743

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

1386

744

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

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;

745

const char *pcret;

746

if(af == AF_INET6){

747

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

748

sizeof(addrstr));

749

} else {

750

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

751

sizeof(addrstr));

752

}

753

if(pcret == NULL){

754

perror_plus("inet_ntop");

755

} else {

756

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

757

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

758

}

759

}

760

}

761

762

if(quit_now){

763

errno = EINTR;

764

goto mandos_end;

765

}

766

767

if(af == AF_INET6){

768

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

769

} else {

770

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

771

}

772

if(ret < 0){

773

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

774

int e = errno;

775

perror_plus("connect");

776

errno = e;

777

}

778

goto mandos_end;

779

}

780

781

if(quit_now){

782

errno = EINTR;

783

goto mandos_end;

1467

784

}

1468

785

1469

786

const char *out = mandos_protocol_version;

1620

937

if(buffer_length > 0){

1621

938

ssize_t decrypted_buffer_size;

1622

939

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1623

&decrypted_buffer, mc);

940

&decrypted_buffer);

1624

941

if(decrypted_buffer_size >= 0){

1625

942

1626

clearerr(stdout);

1627

943

written = 0;

1628

944

while(written < (size_t) decrypted_buffer_size){

1629

945

if(quit_now){

1645

961

}

1646

962

written += (size_t)ret;

1647

963

}

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

}

1658

964

retval = 0;

1659

965

}

1660

966

}

1663

969

1664

970

mandos_end:

1665

971

{

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

}

1672

972

int e = errno;

1673

973

free(decrypted_buffer);

1674

974

free(buffer);

1675

975

if(tcp_sd >= 0){

1676

ret = close(tcp_sd);

976

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

1677

977

}

1678

978

if(ret == -1){

1679

979

if(e == 0){

1704

1004

AVAHI_GCC_UNUSED AvahiStringList *txt,

1705

1005

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1706

1006

flags,

1707

void *mc){

1007

AVAHI_GCC_UNUSED void* userdata){

1708

1008

if(r == NULL){

1709

1009

return;

1710

1010

}

1713

1013

timed out */

1714

1014

1715

1015

if(quit_now){

1716

avahi_s_service_resolver_free(r);

1717

1016

return;

1718

1017

}

1719

1018

1723

1022

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

1724

1023

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

1725

1024

domain,

1726

avahi_strerror(avahi_server_errno

1727

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

1025

avahi_strerror(avahi_server_errno(mc.server)));

1728

1026

break;

1729

1027

1730

1028

case AVAHI_RESOLVER_FOUND:

1738

1036

}

1739

1037

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

1740

1038

interface,

1741

avahi_proto_to_af(proto),

1742

mc);

1039

avahi_proto_to_af(proto));

1743

1040

if(ret == 0){

1744

avahi_simple_poll_quit(simple_poll);

1041

avahi_simple_poll_quit(mc.simple_poll);

1745

1042

} else {

1746

1043

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

1747

avahi_proto_to_af(proto),

1748

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

1044

avahi_proto_to_af(proto))){

1749

1045

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

1750

1046

" list\n", name);

1751

1047

}

1764

1060

const char *domain,

1765

1061

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1766

1062

flags,

1767

void *mc){

1063

AVAHI_GCC_UNUSED void* userdata){

1768

1064

if(b == NULL){

1769

1065

return;

1770

1066

}

1781

1077

case AVAHI_BROWSER_FAILURE:

1782

1078

1783

1079

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);

1080

avahi_strerror(avahi_server_errno(mc.server)));

1081

avahi_simple_poll_quit(mc.simple_poll);

1787

1082

return;

1788

1083

1789

1084

case AVAHI_BROWSER_NEW:

1792

1087

the callback function is called the Avahi server will free the

1793

1088

resolver for us. */

1794

1089

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)

1090

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

1091

name, type, domain, protocol, 0,

1092

resolve_callback, NULL) == NULL)

1799

1093

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

1800

1094

" %s\n", name,

1801

avahi_strerror(avahi_server_errno

1802

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

1095

avahi_strerror(avahi_server_errno(mc.server)));

1803

1096

break;

1804

1097

1805

1098

case AVAHI_BROWSER_REMOVE:

1824

1117

signal_received = sig;

1825

1118

int old_errno = errno;

1826

1119

/* set main loop to exit */

1827

if(simple_poll != NULL){

1828

avahi_simple_poll_quit(simple_poll);

1120

if(mc.simple_poll != NULL){

1121

avahi_simple_poll_quit(mc.simple_poll);

1829

1122

}

1830

1123

errno = old_errno;

1831

1124

}

1832

1125

1833

__attribute__((nonnull, warn_unused_result))

1834

1126

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

1835

1127

int ret;

1836

int old_errno;

1128

error_t ret_errno;

1837

1129

1838

1130

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

1839

1131

if(s < 0){

1840

old_errno = errno;

1132

ret_errno = errno;

1841

1133

perror_plus("socket");

1842

errno = old_errno;

1134

errno = ret_errno;

1843

1135

return false;

1844

1136

}

1845

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

1846

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

1137

strcpy(ifr->ifr_name, ifname);

1847

1138

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1848

1139

if(ret == -1){

1849

1140

if(debug){

1850

old_errno = errno;

1141

ret_errno = errno;

1851

1142

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;

1143

errno = ret_errno;

1858

1144

}

1859

1145

return false;

1860

1146

}

1861

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

1862

old_errno = errno;

1863

perror_plus("close");

1864

errno = old_errno;

1865

}

1866

1147

return true;

1867

1148

}

1868

1149

1869

__attribute__((nonnull, warn_unused_result))

1870

1150

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

1871

1151

1872

1152

/* Reject the loopback device */

1914

1194

* corresponds to an acceptable network device.

1915

1195

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

1916

1196

*/

1917

__attribute__((nonnull, warn_unused_result))

1918

1197

int good_interface(const struct dirent *if_entry){

1919

1198

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

1920

1199

return 0;

1938

1217

/*

1939

1218

* This function determines if a network interface is up.

1940

1219

*/

1941

__attribute__((nonnull, warn_unused_result))

1942

1220

bool interface_is_up(const char *interface){

1943

1221

struct ifreq ifr;

1944

1222

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

1955

1233

/*

1956

1234

* This function determines if a network interface is running

1957

1235

*/

1958

__attribute__((nonnull, warn_unused_result))

1959

1236

bool interface_is_running(const char *interface){

1960

1237

struct ifreq ifr;

1961

1238

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

1969

1246

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

1970

1247

}

1971

1248

1972

__attribute__((nonnull, pure, warn_unused_result))

1973

1249

int notdotentries(const struct dirent *direntry){

1974

1250

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

1975

1251

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

1982

1258

}

1983

1259

1984

1260

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

1985

__attribute__((nonnull, warn_unused_result))

1986

1261

int runnable_hook(const struct dirent *direntry){

1987

1262

int ret;

1988

1263

size_t sret;

1996

1271

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

1997

1272

"abcdefghijklmnopqrstuvwxyz"

1998

1273

"0123456789"

1999

"_.-");

1274

"_-");

2000

1275

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

2001

1276

/* Contains non-allowed characters */

2002

1277

if(debug){

2006

1281

return 0;

2007

1282

}

2008

1283

2009

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

1284

char *fullname = NULL;

1285

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

1286

if(ret < 0){

1287

perror_plus("asprintf");

1288

return 0;

1289

}

1290

1291

ret = stat(fullname, &st);

2010

1292

if(ret == -1){

2011

1293

if(debug){

2012

1294

perror_plus("Could not stat hook");

2036

1318

return 1;

2037

1319

}

2038

1320

2039

__attribute__((nonnull, warn_unused_result))

2040

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

2041

mandos_context *mc){

1321

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

2042

1322

int ret;

2043

1323

struct timespec now;

2044

1324

struct timespec waited_time;

2045

1325

intmax_t block_time;

2046

1326

2047

1327

while(true){

2048

if(mc->current_server == NULL){

2049

if(debug){

1328

if(mc.current_server == NULL){

1329

if (debug){

2050

1330

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

2051

1331

" No timeout!\n");

2052

1332

}

2053

1333

ret = avahi_simple_poll_iterate(s, -1);

2054

1334

} else {

2055

if(debug){

1335

if (debug){

2056

1336

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

2057

1337

" it, or wait\n");

2058

1338

}

2065

1345

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

2066

1346

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

2067

1347

waited_time.tv_sec = (now.tv_sec

2068

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

1348

- mc.current_server->last_seen.tv_sec);

2069

1349

waited_time.tv_nsec = (now.tv_nsec

2070

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

1350

- mc.current_server->last_seen.tv_nsec);

2071

1351

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

2072

1352

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

2073

1353

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

2075

1355

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

2076

1356

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

2077

1357

2078

if(debug){

1358

if (debug){

2079

1359

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

2080

1360

block_time);

2081

1361

}

2082

1362

2083

1363

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);

1364

ret = start_mandos_communication(mc.current_server->ip,

1365

mc.current_server->port,

1366

mc.current_server->if_index,

1367

mc.current_server->af);

2088

1368

if(ret == 0){

2089

avahi_simple_poll_quit(s);

1369

avahi_simple_poll_quit(mc.simple_poll);

2090

1370

return 0;

2091

1371

}

2092

1372

ret = clock_gettime(CLOCK_MONOTONIC,

2093

&mc->current_server->last_seen);

1373

&mc.current_server->last_seen);

2094

1374

if(ret == -1){

2095

1375

perror_plus("clock_gettime");

2096

1376

return -1;

2097

1377

}

2098

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

1378

mc.current_server = mc.current_server->next;

2099

1379

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

2100

1380

servers, but don't block */

2101

1381

}

2103

1383

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

2104

1384

}

2105

1385

if(ret != 0){

2106

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

1386

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

2107

1387

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

2108

1388

}

2109

1389

}

2110

1390

}

2111

1391

}

2112

1392

2113

__attribute__((nonnull))

2114

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

1393

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

1394

error_t raise_privileges(void){

1395

error_t old_errno = errno;

1396

error_t ret_errno = 0;

1397

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

1398

ret_errno = errno;

1399

perror_plus("seteuid");

1400

}

1401

errno = old_errno;

1402

return ret_errno;

1403

}

1404

1405

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

1406

error_t raise_privileges_permanently(void){

1407

error_t old_errno = errno;

1408

error_t ret_errno = raise_privileges();

1409

if(ret_errno != 0){

1410

errno = old_errno;

1411

return ret_errno;

1412

}

1413

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

1414

ret_errno = errno;

1415

perror_plus("seteuid");

1416

}

1417

errno = old_errno;

1418

return ret_errno;

1419

}

1420

1421

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

1422

error_t lower_privileges(void){

1423

error_t old_errno = errno;

1424

error_t ret_errno = 0;

1425

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

1426

ret_errno = errno;

1427

perror_plus("seteuid");

1428

}

1429

errno = old_errno;

1430

return ret_errno;

1431

}

1432

1433

/* Lower privileges permanently */

1434

error_t lower_privileges_permanently(void){

1435

error_t old_errno = errno;

1436

error_t ret_errno = 0;

1437

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

1438

ret_errno = errno;

1439

perror_plus("setuid");

1440

}

1441

errno = old_errno;

1442

return ret_errno;

1443

}

1444

1445

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

2115

1446

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);

1447

struct dirent **direntries;

1448

struct dirent *direntry;

1449

int ret;

1450

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

1451

alphasort);

2139

1452

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);

1453

if(errno == ENOENT){

1454

if(debug){

1455

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

1456

" found\n", hookdir);

1457

}

1458

} else {

1459

perror_plus("scandir");

2151

1460

}

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){

1461

} else {

1462

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

1463

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

1464

direntry = direntries[i];

1465

char *fullname = NULL;

1466

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

1467

if(ret < 0){

2198

1468

perror_plus("asprintf");

2199

_exit(EX_OSERR);

2200

}

2201

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

2202

if(ret == -1){

1469

continue;

1470

}

1471

if(debug){

1472

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

1473

direntry->d_name);

1474

}

1475

pid_t hook_pid = fork();

1476

if(hook_pid == 0){

1477

/* Child */

1478

/* Raise privileges */

1479

raise_privileges_permanently();

1480

/* Set group */

1481

errno = 0;

1482

ret = setgid(0);

1483

if(ret == -1){

1484

perror_plus("setgid");

1485

}

1486

/* Reset supplementary groups */

1487

errno = 0;

1488

ret = setgroups(0, NULL);

1489

if(ret == -1){

1490

perror_plus("setgroups");

1491

}

1492

dup2(devnull, STDIN_FILENO);

1493

close(devnull);

1494

dup2(STDERR_FILENO, STDOUT_FILENO);

1495

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

1496

if(ret == -1){

1497

perror_plus("setenv");

1498

_exit(EX_OSERR);

1499

}

1500

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

1501

if(ret == -1){

1502

perror_plus("setenv");

1503

_exit(EX_OSERR);

1504

}

1505

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

1506

if(ret == -1){

1507

perror_plus("setenv");

1508

_exit(EX_OSERR);

1509

}

1510

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

1511

if(ret == -1){

1512

perror_plus("setenv");

1513

_exit(EX_OSERR);

1514

}

1515

char *delaystring;

1516

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

1517

if(ret == -1){

1518

perror_plus("asprintf");

1519

_exit(EX_OSERR);

1520

}

1521

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

1522

if(ret == -1){

1523

free(delaystring);

1524

perror_plus("setenv");

1525

_exit(EX_OSERR);

1526

}

2203

1527

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;

1528

if(connect_to != NULL){

1529

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

1530

if(ret == -1){

1531

perror_plus("setenv");

1532

_exit(EX_OSERR);

1533

}

1534

}

1535

if(execl(fullname, direntry->d_name, mode, NULL) == -1){

1536

perror_plus("execl");

1537

_exit(EXIT_FAILURE);

1538

}

2272

1539

} 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);

1540

int status;

1541

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

1542

perror_plus("waitpid");

1543

free(fullname);

1544

continue;

1545

}

1546

if(WIFEXITED(status)){

1547

if(WEXITSTATUS(status) != 0){

1548

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

1549

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

1550

WEXITSTATUS(status));

1551

free(fullname);

1552

continue;

1553

}

1554

} else if(WIFSIGNALED(status)){

1555

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

1556

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

1557

WTERMSIG(status));

1558

free(fullname);

1559

continue;

1560

} else {

1561

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

1562

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

1563

free(fullname);

1564

continue;

1565

}

1566

}

1567

free(fullname);

1568

if(debug){

1569

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

1570

direntry->d_name);

1571

}

1572

}

1573

close(devnull);

1574

}

1575

return true;

2292

1576

}

2293

1577

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;

1578

error_t bring_up_interface(const char *const interface,

1579

const float delay){

1580

int sd = -1;

1581

error_t old_errno = errno;

1582

error_t ret_errno = 0;

1583

int ret, ret_setflags;

2299

1584

struct ifreq network;

2300

1585

unsigned int if_index = if_nametoindex(interface);

2301

1586

if(if_index == 0){

2310

1595

}

2311

1596

2312

1597

if(not interface_is_up(interface)){

2313

int ret_errno = 0;

2314

int ioctl_errno = 0;

2315

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

1598

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

2316

1599

ret_errno = errno;

2317

1600

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

2318

1601

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

2319

errno = old_errno;

2320

1602

return ret_errno;

2321

1603

}

2322

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

1604

network.ifr_flags |= IFF_UP;

2323

1605

2324

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

2325

if(sd == -1){

1606

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1607

if(sd < 0){

2326

1608

ret_errno = errno;

2327

1609

perror_plus("socket");

2328

1610

errno = old_errno;

2329

1611

return ret_errno;

2330

1612

}

2331

1613

2332

1614

if(quit_now){

2333

ret = close(sd);

2334

if(ret == -1){

2335

perror_plus("close");

2336

}

1615

close(sd);

2337

1616

errno = old_errno;

2338

1617

return EINTR;

2339

1618

}

2343

1622

interface);

2344

1623

}

2345

1624

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

}

1625

/* Raise priviliges */

1626

raise_privileges();

2352

1627

2353

1628

#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

}

1629

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1630

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

1631

int ret_linux = klogctl(8, NULL, 5);

1632

bool restore_loglevel = true;

1633

if(ret_linux == -1){

1634

restore_loglevel = false;

1635

perror_plus("klogctl");

2365

1636

}

2366

1637

#endif /* __linux__ */

2367

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

2368

ioctl_errno = errno;

1638

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

1639

ret_errno = errno;

2369

1640

#ifdef __linux__

2370

1641

if(restore_loglevel){

2371

1642

ret_linux = klogctl(7, NULL, 0);

2375

1646

}

2376

1647

#endif /* __linux__ */

2377

1648

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

}

1649

/* Lower privileges */

1650

lower_privileges();

2387

1651

2388

1652

/* Close the socket */

2389

ret = close(sd);

1653

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

2390

1654

if(ret == -1){

2391

1655

perror_plus("close");

2392

1656

}

2393

1657

2394

1658

if(ret_setflags == -1){

2395

errno = ioctl_errno;

1659

errno = ret_errno;

2396

1660

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2397

1661

errno = old_errno;

2398

return ioctl_errno;

1662

return ret_errno;

2399

1663

}

2400

1664

} else if(debug){

2401

1665

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

2404

1668

2405

1669

/* Sleep checking until interface is running.

2406

1670

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

2407

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

1671

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

2408

1672

if(interface_is_running(interface)){

2409

1673

break;

2410

1674

}

2419

1683

return 0;

2420

1684

}

2421

1685

2422

__attribute__((nonnull, warn_unused_result))

2423

int take_down_interface(const char *const interface){

2424

int old_errno = errno;

1686

error_t take_down_interface(const char *const interface){

1687

int sd = -1;

1688

error_t old_errno = errno;

1689

error_t ret_errno = 0;

1690

int ret, ret_setflags;

2425

1691

struct ifreq network;

2426

1692

unsigned int if_index = if_nametoindex(interface);

2427

1693

if(if_index == 0){

2430

1696

return ENXIO;

2431

1697

}

2432

1698

if(interface_is_up(interface)){

2433

int ret_errno = 0;

2434

int ioctl_errno = 0;

2435

1699

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

2436

1700

ret_errno = errno;

2437

1701

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

2438

1702

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

2439

errno = old_errno;

2440

1703

return ret_errno;

2441

1704

}

2442

1705

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

2443

1706

2444

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

2445

if(sd == -1){

1707

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1708

if(sd < 0){

2446

1709

ret_errno = errno;

2447

1710

perror_plus("socket");

2448

1711

errno = old_errno;

2454

1717

interface);

2455

1718

}

2456

1719

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

}

1720

/* Raise priviliges */

1721

raise_privileges();

1722

1723

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

1724

ret_errno = errno;

1725

1726

/* Lower privileges */

1727

lower_privileges();

2476

1728

2477

1729

/* Close the socket */

2478

int ret = close(sd);

1730

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

2479

1731

if(ret == -1){

2480

1732

perror_plus("close");

2481

1733

}

2482

1734

2483

1735

if(ret_setflags == -1){

2484

errno = ioctl_errno;

1736

errno = ret_errno;

2485

1737

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2486

1738

errno = old_errno;

2487

return ioctl_errno;

1739

return ret_errno;

2488

1740

}

2489

1741

} else if(debug){

2490

1742

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

2496

1748

}

2497

1749

2498

1750

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 };

2512

1751

AvahiSServiceBrowser *sb = NULL;

2513

1752

error_t ret_errno;

2514

1753

int ret;

2515

1754

intmax_t tmpmax;

2516

1755

char *tmp;

2517

1756

int exitcode = EXIT_SUCCESS;

1757

char *interfaces = NULL;

1758

size_t interfaces_size = 0;

2518

1759

char *interfaces_to_take_down = NULL;

2519

1760

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;

1761

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

1762

bool tempdir_created = false;

2523

1763

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2524

1764

const char *seckey = PATHDIR "/" SECKEY;

2525

1765

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

1766

char *interfaces_hooks = NULL;

1767

size_t interfaces_hooks_size = 0;

2532

1768

2533

1769

bool gnutls_initialized = false;

2534

1770

bool gpgme_initialized = false;

2580

1816

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

2581

1817

.arg = "FILE",

2582

1818

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

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 },

1819

.group = 2 },

2600

1820

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

2601

1821

.arg = "BITS",

2602

1822

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

2603

1823

" Diffie-Hellman key exchange",

2604

1824

.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 },

2610

1825

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

2611

1826

.arg = "STRING",

2612

1827

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

2646

1861

connect_to = arg;

2647

1862

break;

2648

1863

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

2649

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

2650

arg, (int)',');

1864

ret_errno = argz_add_sep(&interfaces, &interfaces_size, arg,

1865

(int)',');

2651

1866

if(ret_errno != 0){

2652

1867

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

2653

1868

}

2658

1873

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

2659

1874

pubkey = arg;

2660

1875

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;

2671

1876

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

2672

1877

errno = 0;

2673

1878

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

2677

1882

}

2678

1883

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

2679

1884

break;

2680

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

2681

dh_params_file = arg;

2682

break;

2683

1885

case 130: /* --priority */

2684

1886

mc.priority = arg;

2685

1887

break;

2708

1910

argp_state_help(state, state->out_stream,

2709

1911

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

2710

1912

& ~(unsigned int)ARGP_HELP_EXIT_OK);

2711

__builtin_unreachable();

2712

1913

case -3: /* --usage */

2713

1914

argp_state_help(state, state->out_stream,

2714

1915

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2715

__builtin_unreachable();

2716

1916

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

2717

1917

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

2718

1918

exit(argp_err_exit_status);

2727

1927

.args_doc = "",

2728

1928

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

2729

1929

" passwords from a Mandos server" };

2730

ret_errno = argp_parse(&argp, argc, argv,

2731

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2732

switch(ret_errno){

1930

ret = argp_parse(&argp, argc, argv,

1931

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1932

switch(ret){

2733

1933

case 0:

2734

1934

break;

2735

1935

case ENOMEM:

2736

1936

default:

2737

errno = ret_errno;

1937

errno = ret;

2738

1938

perror_plus("argp_parse");

2739

1939

exitcode = EX_OSERR;

2740

1940

goto end;

2743

1943

goto end;

2744

1944

}

2745

1945

}

2746

1946

2747

1947

{

2748

/* Re-raise privileges */

2749

ret = raise_privileges();

2750

if(ret != 0){

2751

errno = ret;

2752

perror_plus("Failed to raise privileges");

2753

} else {

1948

/* Work around Debian bug #633582:

1949

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

1950

1951

/* Re-raise priviliges */

1952

if(raise_privileges() == 0){

2754

1953

struct stat st;

2755

1954

2756

/* Work around Debian bug #633582:

2757

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

2758

2759

1955

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

2760

1956

int seckey_fd = open(seckey, O_RDONLY);

2761

1957

if(seckey_fd == -1){

2773

1969

}

2774

1970

}

2775

1971

}

2776

close(seckey_fd);

1972

TEMP_FAILURE_RETRY(close(seckey_fd));

2777

1973

}

2778

1974

}

2779

1975

2780

1976

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

2781

1977

int pubkey_fd = open(pubkey, O_RDONLY);

2782

1978

if(pubkey_fd == -1){

2794

1990

}

2795

1991

}

2796

1992

}

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

1993

TEMP_FAILURE_RETRY(close(pubkey_fd));

1994

}

1995

}

1996

2832

1997

/* Lower privileges */

2833

ret = lower_privileges();

2834

if(ret != 0){

2835

errno = ret;

2836

perror_plus("Failed to lower privileges");

1998

errno = 0;

1999

ret = seteuid(uid);

2000

if(ret == -1){

2001

perror_plus("seteuid");

2837

2002

}

2838

2003

}

2839

2004

}

2840

2005

2841

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

2006

/* Remove empty interface names */

2842

2007

{

2843

2008

char *interface = NULL;

2844

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

2009

while((interface = argz_next(interfaces, interfaces_size,

2845

2010

interface))){

2846

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

2847

and if_nametoindex(interface) == 0){

2848

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

2011

if(if_nametoindex(interface) == 0){

2012

if(interface[0] != '\0' and strcmp(interface, "none") != 0){

2849

2013

fprintf_plus(stderr, "Not using nonexisting interface"

2850

2014

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

2851

2015

}

2852

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

2016

argz_delete(&interfaces, &interfaces_size, interface);

2853

2017

interface = NULL;

2854

2018

}

2855

2019

}

2857

2021

2858

2022

/* Run network hooks */

2859

2023

{

2860

if(mc.interfaces != NULL){

2861

interfaces_hooks = malloc(mc.interfaces_size);

2024

2025

if(interfaces != NULL){

2026

interfaces_hooks = malloc(interfaces_size);

2862

2027

if(interfaces_hooks == NULL){

2863

2028

perror_plus("malloc");

2864

2029

goto end;

2865

2030

}

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);

2031

memcpy(interfaces_hooks, interfaces, interfaces_size);

2032

interfaces_hooks_size = interfaces_size;

2033

argz_stringify(interfaces_hooks, interfaces_hooks_size,

2034

(int)',');

2035

}

2036

if(not run_network_hooks("start", interfaces_hooks != NULL ?

2037

interfaces_hooks : "", delay)){

2038

goto end;

2039

}

2871

2040

}

2872

2041

2873

2042

if(not debug){

2878

2047

from the signal handler */

2879

2048

/* Initialize the pseudo-RNG for Avahi */

2880

2049

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

2881

simple_poll = avahi_simple_poll_new();

2882

if(simple_poll == NULL){

2050

mc.simple_poll = avahi_simple_poll_new();

2051

if(mc.simple_poll == NULL){

2883

2052

fprintf_plus(stderr,

2884

2053

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

2885

2054

exitcode = EX_UNAVAILABLE;

2950

2119

}

2951

2120

2952

2121

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

2953

if(mc.interfaces == NULL){

2954

struct dirent **direntries = NULL;

2122

if(interfaces == NULL){

2123

struct dirent **direntries;

2955

2124

/* Look for any good interfaces */

2956

2125

ret = scandir(sys_class_net, &direntries, good_interface,

2957

2126

alphasort);

2958

2127

if(ret >= 1){

2959

2128

/* Add all found interfaces to interfaces list */

2960

2129

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

2961

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

2130

ret_errno = argz_add(&interfaces, &interfaces_size,

2962

2131

direntries[i]->d_name);

2963

2132

if(ret_errno != 0){

2964

errno = ret_errno;

2965

2133

perror_plus("argz_add");

2966

free(direntries[i]);

2967

2134

continue;

2968

2135

}

2969

2136

if(debug){

2970

2137

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

2971

2138

direntries[i]->d_name);

2972

2139

}

2973

free(direntries[i]);

2974

2140

}

2975

2141

free(direntries);

2976

2142

} else {

2977

if(ret == 0){

2978

free(direntries);

2979

}

2143

free(direntries);

2980

2144

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

2981

2145

exitcode = EXIT_FAILURE;

2982

2146

goto end;

2983

2147

}

2984

2148

}

2985

2149

2986

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

2987

{

2150

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

2151

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

2152

if(debug){

2153

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

2154

interfaces);

2155

}

2156

if_index = (AvahiIfIndex)if_nametoindex(interfaces);

2157

}

2158

2159

/* Bring up interfaces which are down */

2160

if(not (argz_count(interfaces, interfaces_size) == 1

2161

and strcmp(interfaces, "none") == 0)){

2988

2162

char *interface = NULL;

2989

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

2163

while((interface = argz_next(interfaces, interfaces_size,

2990

2164

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;

3003

}

3004

}

3005

break;

3006

}

3007

2165

bool interface_was_up = interface_is_up(interface);

3008

errno = bring_up_interface(interface, delay);

2166

ret = bring_up_interface(interface, delay);

3009

2167

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));

2168

if(ret != 0){

2169

errno = ret;

2170

perror_plus("Failed to bring up interface");

3013

2171

} 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

}

2172

ret_errno = argz_add(&interfaces_to_take_down,

2173

&interfaces_to_take_down_size,

2174

interface);

3020

2175

}

3021

2176

}

3022

2177

}

2178

free(interfaces);

2179

interfaces = NULL;

2180

interfaces_size = 0;

3023

2181

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

3024

2182

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

3025

2183

}

3026

2184

}

3027

2185

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);

3035

}

3036

3037

2186

if(quit_now){

3038

2187

goto end;

3039

2188

}

3040

2189

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

2190

ret = init_gnutls_global(pubkey, seckey);

3048

2191

if(ret == -1){

3049

2192

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

3050

2193

exitcode = EX_UNAVAILABLE;

3057

2200

goto end;

3058

2201

}

3059

2202

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){

2203

if(mkdtemp(tempdir) == NULL){

3070

2204

perror_plus("mkdtemp");

3071

2205

goto end;

3072

2206

}

2207

tempdir_created = true;

3073

2208

3074

2209

if(quit_now){

3075

2210

goto end;

3076

2211

}

3077

2212

3078

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

2213

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

3079

2214

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

3080

2215

exitcode = EX_UNAVAILABLE;

3081

2216

goto end;

3111

2246

exitcode = EX_USAGE;

3112

2247

goto end;

3113

2248

}

3114

2249

3115

2250

if(quit_now){

3116

2251

goto end;

3117

2252

}

3138

2273

}

3139

2274

3140

2275

while(not quit_now){

3141

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

3142

&mc);

2276

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

3143

2277

if(quit_now or ret == 0){

3144

2278

break;

3145

2279

}

3147

2281

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

3148

2282

(int)retry_interval);

3149

2283

}

3150

sleep((unsigned int)retry_interval);

2284

sleep((int)retry_interval);

3151

2285

}

3152

2286

3153

if(not quit_now){

2287

if (not quit_now){

3154

2288

exitcode = EXIT_SUCCESS;

3155

2289

}

3156

2290

3171

2305

config.publish_domain = 0;

3172

2306

3173

2307

/* Allocate a new server */

3174

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

3175

&config, NULL, NULL, &ret);

2308

mc.server = avahi_server_new(avahi_simple_poll_get

2309

(mc.simple_poll), &config, NULL,

2310

NULL, &ret_errno);

3176

2311

3177

2312

/* Free the Avahi configuration data */

3178

2313

avahi_server_config_free(&config);

3181

2316

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

3182

2317

if(mc.server == NULL){

3183

2318

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

3184

avahi_strerror(ret));

2319

avahi_strerror(ret_errno));

3185

2320

exitcode = EX_UNAVAILABLE;

3186

2321

goto end;

3187

2322

}

3193

2328

/* Create the Avahi service browser */

3194

2329

sb = avahi_s_service_browser_new(mc.server, if_index,

3195

2330

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

3196

NULL, 0, browse_callback,

3197

(void *)&mc);

2331

NULL, 0, browse_callback, NULL);

3198

2332

if(sb == NULL){

3199

2333

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

3200

2334

avahi_strerror(avahi_server_errno(mc.server)));

3211

2345

if(debug){

3212

2346

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

3213

2347

}

3214

3215

ret = avahi_loop_with_timeout(simple_poll,

3216

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

2348

2349

ret = avahi_loop_with_timeout(mc.simple_poll,

2350

(int)(retry_interval * 1000));

3217

2351

if(debug){

3218

2352

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

3219

2353

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

3222

2356

end:

3223

2357

3224

2358

if(debug){

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

}

2359

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

3232

2360

}

3233

2361

3234

2362

/* Cleanup things */

3235

free(mc.interfaces);

3236

3237

2363

if(sb != NULL)

3238

2364

avahi_s_service_browser_free(sb);

3239

2365

3240

2366

if(mc.server != NULL)

3241

2367

avahi_server_free(mc.server);

3242

2368

3243

if(simple_poll != NULL)

3244

avahi_simple_poll_free(simple_poll);

2369

if(mc.simple_poll != NULL)

2370

avahi_simple_poll_free(mc.simple_poll);

3245

2371

3246

2372

if(gnutls_initialized){

3247

2373

gnutls_certificate_free_credentials(mc.cred);

2374

gnutls_global_deinit();

3248

2375

gnutls_dh_params_deinit(mc.dh_params);

3249

2376

}

3250

2377

3258

2385

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

3259

2386

while(mc.current_server != NULL){

3260

2387

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

2388

free(mc.current_server);

3270

2389

mc.current_server = next;

3271

2390

}

3272

2391

}

3273

2392

3274

/* Re-raise privileges */

2393

/* Re-raise priviliges */

3275

2394

{

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

}

2395

raise_privileges();

2396

2397

/* Run network hooks */

2398

run_network_hooks("stop", interfaces_hooks != NULL ?

2399

interfaces_hooks : "", delay);

2400

2401

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

2402

{

2403

char *interface = NULL;

2404

while((interface=argz_next(interfaces_to_take_down,

2405

interfaces_to_take_down_size,

2406

interface))){

2407

ret_errno = take_down_interface(interface);

2408

if(ret_errno != 0){

2409

errno = ret_errno;

2410

perror_plus("Failed to take down interface");

2411

}

2412

}

2413

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

2414

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

2415

" down\n");

2416

}

2417

}

2418

2419

lower_privileges_permanently();

3310

2420

}

3311

2421

3312

2422

free(interfaces_to_take_down);

3313

2423

free(interfaces_hooks);

3314

2424

3315

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

3316

uintmax_t level){

2425

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

2426

if(tempdir_created){

3317

2427

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){

2428

struct dirent *direntry = NULL;

2429

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

2430

alphasort);

2431

if (numentries > 0){

3331

2432

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);

2433

direntry = direntries[i];

2434

char *fullname = NULL;

2435

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

2436

direntry->d_name);

2437

if(ret < 0){

2438

perror_plus("asprintf");

2439

continue;

2440

}

2441

ret = remove(fullname);

2442

if(ret == -1){

2443

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

2444

strerror(errno));

2445

}

2446

free(fullname);

2447

}

2448

}

2449

2450

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

2451

free(direntries);

2452

if (numentries == -1){

2453

perror_plus("scandir");

2454

}

2455

ret = rmdir(tempdir);

2456

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

2457

perror_plus("rmdir");

2458

}

3372

2459

}

3373

2460

3374

2461

if(quit_now){