/mandos/trunk : revision 1292

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

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*

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* Everything else is

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*

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

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

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

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

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*

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

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*

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* This file is part of Mandos.

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*

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

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

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

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* (at your option) any later version.

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*

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

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* WITHOUT ANY WARRANTY; without even the implied warranty of

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

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* General Public License for more details.

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*

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

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* along with this program. If not, see

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

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

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*

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

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*/

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

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#ifndef _LARGEFILE_SOURCE

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#define _LARGEFILE_SOURCE

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#endif

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#endif /* not _LARGEFILE_SOURCE */

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#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

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#endif

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#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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#endif /* not _FILE_OFFSET_BITS */

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#define _GNU_SOURCE /* program_invocation_short_name,

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TEMP_FAILURE_RETRY(), O_CLOEXEC,

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scandirat(), asprintf() */

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

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

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

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

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

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sockaddr_in6, PF_INET6,

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SOCK_STREAM, uid_t, gid_t, open(),

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opendir(), DIR */

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

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

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inet_pton(), connect(),

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getnameinfo() */

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

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

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*/

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

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#include <argp.h> /* argp_program_version,

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argp_program_bug_address,

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struct argp_option,

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struct argp_state, argp_error(),

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argp_state_help,

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ARGP_HELP_STD_HELP,

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ARGP_HELP_EXIT_ERR,

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ARGP_HELP_EXIT_OK, ARGP_HELP_USAGE,

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argp_err_exit_status,

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ARGP_ERR_UNKNOWN, struct argp,

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argp_parse(), ARGP_IN_ORDER,

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ARGP_NO_HELP */

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

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

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seteuid(), setuid(), pid_t,

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

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

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

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

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_exit(), dup2(), STDIN_FILENO,

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STDERR_FILENO, STDOUT_FILENO,

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

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

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

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

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sa_family_t, struct sockaddr_in,

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htons(), IN6_IS_ADDR_LINKLOCAL,

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INET_ADDRSTRLEN, INET6_ADDRSTRLEN,

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ntohl(), IPPROTO_IP */

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

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CLOCK_MONOTONIC, time_t, struct tm,

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gmtime_r(), clock_settime(),

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CLOCK_REALTIME, nanosleep() */

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#include <errno.h> /* errno,

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program_invocation_short_name,

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EINTR, EINVAL, ENETUNREACH,

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EHOSTUNREACH, ECONNREFUSED, EPROTO,

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EIO, ENOENT, ENXIO, error_t,

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ENOMEM, EISDIR, ENOTEMPTY */

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

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vfprintf(), off_t, SEEK_SET,

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stdout, fwrite(), ferror(),

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fflush(), asprintf() */

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

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

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getenv(), EXIT_FAILURE, setenv(),

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EXIT_SUCCESS, strtof(), strtod(),

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

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

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

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

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strsignal() */

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

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O_PATH, O_CLOEXEC, openat(),

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O_NOFOLLOW, AT_REMOVEDIR */

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

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

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S_ISREG(), S_IXUSR, S_IXGRP,

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S_IXOTH, lstat() */

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

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if_nametoindex(), SIOCGIFFLAGS,

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IFF_LOOPBACK, IFF_POINTOPOINT,

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IFF_BROADCAST, IFF_NOARP, IFF_UP,

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IFF_RUNNING, SIOCSIFFLAGS */

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

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EX_UNAVAILABLE, EX_USAGE */

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

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

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WEXITSTATUS(), WIFSIGNALED(),

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WTERMSIG() */

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

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SIG_DFL, sigemptyset(),

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sigaddset(), SIGINT, SIGHUP,

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SIG_IGN, raise() */

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

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PF_INET6, AF_INET, PF_INET,

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socket(), SOCK_STREAM,

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SOCK_CLOEXEC, struct sockaddr,

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connect(), SOCK_DGRAM */

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

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argz_delete(), argz_stringify(),

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argz_add(), argz_count() */

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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 <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() */

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

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argz_delete(), argz_append(),

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argz_stringify(), argz_add(),

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argz_count() */

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#include <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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#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:

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gnutls_*

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init_gnutls_session(),

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GNUTLS_* */

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functions: gnutls_*, GNUTLS_* */

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#if GNUTLS_VERSION_NUMBER < 0x030600

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#include <gnutls/openpgp.h>

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/* gnutls_certificate_set_openpgp_key_file(),

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GNUTLS_OPENPGP_FMT_BASE64 */

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#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_*

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GPGME_PROTOCOL_OpenPGP,

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GPG_ERR_NO_* */

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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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#define BUFFER_SIZE 256

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

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#define SECKEY "seckey.txt"

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#define PUBKEY "pubkey.txt"

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#define TLS_PRIVKEY "tls-privkey.pem"

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#define TLS_PUBKEY "tls-pubkey.pem"

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

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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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perror(print_text);

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}

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

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

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

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va_list ap;

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va_start (ap, format);

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

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* "buffer_length" is how much is already used.

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*/

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__attribute__((nonnull, warn_unused_result))

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size_t incbuffer(char **buffer, size_t buffer_length,

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size_t buffer_capacity){

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if(buffer_length + BUFFER_SIZE > buffer_capacity){

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}

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

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__attribute__((nonnull, warn_unused_result))

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

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int af, server **current_server){

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int ret;

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.af = af };

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if(new_server->ip == NULL){

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perror_plus("strdup");

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free(new_server);

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return false;

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}

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

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if(ret == -1){

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perror_plus("clock_gettime");

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#ifdef __GNUC__

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#pragma GCC diagnostic push

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#pragma GCC diagnostic ignored "-Wcast-qual"

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#endif

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

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#ifdef __GNUC__

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#pragma GCC diagnostic pop

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#endif

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free(new_server);

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return false;

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}

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/* Special case of first server */

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new_server->next = new_server;

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new_server->prev = new_server;

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*current_server = new_server;

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

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} else {

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

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new_server->next = *current_server;

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

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new_server->prev->next = new_server;

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return true;

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}

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

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__attribute__((warn_unused_result))

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int raise_privileges(void){

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int old_errno = errno;

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int ret = 0;

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

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ret = errno;

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}

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errno = old_errno;

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return ret;

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}

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

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__attribute__((warn_unused_result))

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int raise_privileges_permanently(void){

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int old_errno = errno;

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int ret = raise_privileges();

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if(ret != 0){

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errno = old_errno;

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return ret;

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}

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

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ret = errno;

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}

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errno = old_errno;

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return ret;

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}

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

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__attribute__((warn_unused_result))

343

int lower_privileges(void){

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int old_errno = errno;

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int ret = 0;

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

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ret = errno;

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}

349

errno = old_errno;

350

return ret;

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}

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/* Lower privileges permanently */

354

__attribute__((warn_unused_result))

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int lower_privileges_permanently(void){

356

int old_errno = errno;

357

int ret = 0;

358

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

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ret = errno;

360

}

361

errno = old_errno;

362

return ret;

363

}

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/*

256

366

* Initialize GPGME.

257

367

*/

258

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

259

const char *tempdir, mandos_context *mc){

368

__attribute__((nonnull, warn_unused_result))

369

static bool init_gpgme(const char * const seckey,

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const char * const pubkey,

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const char * const tempdir,

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mandos_context *mc){

260

373

gpgme_error_t rc;

261

374

gpgme_engine_info_t engine_info;

262

375

263

376

/*

264

377

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

265

378

*/

266

bool import_key(const char *filename){

379

bool import_key(const char * const filename){

267

380

int ret;

268

381

int fd;

269

382

gpgme_data_t pgp_data;

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387

return false;

275

388

}

276

389

390

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

391

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

392

do {

393

{

394

time_t currtime = time(NULL);

395

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

396

struct tm tm;

397

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

398

perror_plus("gmtime_r");

399

break;

400

}

401

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

402

break;

403

}

404

if(debug){

405

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

406

}

407

} else {

408

if(debug){

409

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

410

}

411

}

412

}

413

struct stat keystat;

414

ret = fstat(fd, &keystat);

415

if(ret != 0){

416

perror_plus("fstat");

417

break;

418

}

419

ret = raise_privileges();

420

if(ret != 0){

421

errno = ret;

422

perror_plus("Failed to raise privileges");

423

break;

424

}

425

if(debug){

426

fprintf_plus(stderr,

427

"Setting system clock to key file mtime");

428

}

429

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

430

perror_plus("clock_settime");

431

}

432

ret = lower_privileges();

433

if(ret != 0){

434

errno = ret;

435

perror_plus("Failed to lower privileges");

436

}

437

} while(false);

438

277

439

rc = gpgme_data_new_from_fd(&pgp_data, fd);

278

440

if(rc != GPG_ERR_NO_ERROR){

279

441

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

287

449

gpgme_strsource(rc), gpgme_strerror(rc));

288

450

return false;

289

451

}

452

{

453

gpgme_import_result_t import_result

454

= gpgme_op_import_result(mc->ctx);

455

if((import_result->imported < 1

456

or import_result->not_imported > 0)

457

and import_result->unchanged == 0){

458

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

459

fprintf_plus(stderr,

460

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

461

import_result->considered);

462

fprintf_plus(stderr,

463

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

464

import_result->no_user_id);

465

fprintf_plus(stderr,

466

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

467

import_result->imported);

468

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

469

import_result->imported_rsa);

470

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

471

import_result->unchanged);

472

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

473

import_result->new_user_ids);

474

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

475

import_result->new_sub_keys);

476

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

477

import_result->new_signatures);

478

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

479

import_result->new_revocations);

480

fprintf_plus(stderr,

481

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

482

import_result->secret_read);

483

fprintf_plus(stderr,

484

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

485

import_result->secret_imported);

486

fprintf_plus(stderr,

487

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

488

import_result->secret_unchanged);

489

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

490

import_result->not_imported);

491

for(gpgme_import_status_t import_status

492

= import_result->imports;

493

import_status != NULL;

494

import_status = import_status->next){

495

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

496

import_status->fpr);

497

if(import_status->result != GPG_ERR_NO_ERROR){

498

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

499

gpgme_strsource(import_status->result),

500

gpgme_strerror(import_status->result));

501

}

502

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

503

fprintf_plus(stderr,

504

import_status->status & GPGME_IMPORT_NEW

505

? "The key was new.\n"

506

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

507

fprintf_plus(stderr,

508

import_status->status & GPGME_IMPORT_UID

509

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

510

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

511

fprintf_plus(stderr,

512

import_status->status & GPGME_IMPORT_SIG

513

? "The key contained new signatures.\n"

514

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

515

fprintf_plus(stderr,

516

import_status->status & GPGME_IMPORT_SUBKEY

517

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

518

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

519

fprintf_plus(stderr,

520

import_status->status & GPGME_IMPORT_SECRET

521

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

522

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

523

}

524

return false;

525

}

526

}

290

527

291

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

528

ret = close(fd);

292

529

if(ret == -1){

293

530

perror_plus("close");

294

531

}

333

570

/* Create new GPGME "context" */

334

571

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

335

572

if(rc != GPG_ERR_NO_ERROR){

336

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

337

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

338

gpgme_strerror(rc));

573

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

574

gpgme_strsource(rc), gpgme_strerror(rc));

339

575

return false;

340

576

}

341

577

350

586

* Decrypt OpenPGP data.

351

587

* Returns -1 on error

352

588

*/

589

__attribute__((nonnull, warn_unused_result))

353

590

static ssize_t pgp_packet_decrypt(const char *cryptotext,

354

591

size_t crypto_size,

355

592

char **plaintext,

376

613

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

377

614

rc = gpgme_data_new(&dh_plain);

378

615

if(rc != GPG_ERR_NO_ERROR){

379

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

380

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

616

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

381

617

gpgme_strsource(rc), gpgme_strerror(rc));

382

618

gpgme_data_release(dh_crypto);

383

619

return -1;

396

632

if(result == NULL){

397

633

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

398

634

} else {

399

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

400

result->unsupported_algorithm);

401

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

402

result->wrong_key_usage);

635

if(result->unsupported_algorithm != NULL) {

636

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

637

result->unsupported_algorithm);

638

}

639

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

640

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

403

641

if(result->file_name != NULL){

404

642

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

405

643

}

406

gpgme_recipient_t recipient;

407

recipient = result->recipients;

408

while(recipient != NULL){

644

645

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

646

r = r->next){

409

647

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

410

gpgme_pubkey_algo_name

411

(recipient->pubkey_algo));

412

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

648

gpgme_pubkey_algo_name(r->pubkey_algo));

649

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

413

650

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

414

recipient->status == GPG_ERR_NO_SECKEY

415

? "No" : "Yes");

416

recipient = recipient->next;

651

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

417

652

}

418

653

}

419

654

}

475

710

return plaintext_length;

476

711

}

477

712

478

static const char * safer_gnutls_strerror(int value){

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){

479

722

const char *ret = gnutls_strerror(value);

480

if(ret == NULL)

481

ret = "(unknown)";

482

return ret;

723

return safe_string(ret);

483

724

}

484

725

485

726

/* GnuTLS log function callback */

727

__attribute__((nonnull))

486

728

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

487

729

const char* string){

488

730

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

489

731

}

490

732

733

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

491

734

static int init_gnutls_global(const char *pubkeyfilename,

492

735

const char *seckeyfilename,

736

const char *dhparamsfilename,

493

737

mandos_context *mc){

494

738

int ret;

495

739

497

741

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

498

742

}

499

743

500

ret = gnutls_global_init();

501

if(ret != GNUTLS_E_SUCCESS){

502

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

503

safer_gnutls_strerror(ret));

504

return -1;

505

}

506

507

744

if(debug){

508

745

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

509

746

* - GnuTLS manual

517

754

if(ret != GNUTLS_E_SUCCESS){

518

755

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

519

756

safer_gnutls_strerror(ret));

520

gnutls_global_deinit();

521

757

return -1;

522

758

}

523

759

524

760

if(debug){

525

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

526

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

761

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

762

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

527

763

pubkeyfilename,

528

764

seckeyfilename);

529

765

}

530

766

767

#if GNUTLS_VERSION_NUMBER >= 0x030606

768

ret = gnutls_certificate_set_rawpk_key_file

769

(mc->cred, pubkeyfilename, seckeyfilename,

770

GNUTLS_X509_FMT_PEM, /* format */

771

NULL, /* pass */

772

/* key_usage */

773

GNUTLS_KEY_DIGITAL_SIGNATURE | GNUTLS_KEY_KEY_ENCIPHERMENT,

774

NULL, /* names */

775

0, /* names_length */

776

/* privkey_flags */

777

GNUTLS_PKCS_PLAIN | GNUTLS_PKCS_NULL_PASSWORD,

778

0); /* pkcs11_flags */

779

#elif GNUTLS_VERSION_NUMBER < 0x030600

531

780

ret = gnutls_certificate_set_openpgp_key_file

532

781

(mc->cred, pubkeyfilename, seckeyfilename,

533

782

GNUTLS_OPENPGP_FMT_BASE64);

783

#else

784

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

785

#endif

534

786

if(ret != GNUTLS_E_SUCCESS){

535

787

fprintf_plus(stderr,

536

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

788

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

537

789

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

538

790

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

539

791

safer_gnutls_strerror(ret));

548

800

safer_gnutls_strerror(ret));

549

801

goto globalfail;

550

802

}

551

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

552

if(ret != GNUTLS_E_SUCCESS){

553

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

554

safer_gnutls_strerror(ret));

555

goto globalfail;

556

}

557

558

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

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

}

559

985

560

986

return 0;

561

987

562

988

globalfail:

563

989

564

990

gnutls_certificate_free_credentials(mc->cred);

565

gnutls_global_deinit();

566

991

gnutls_dh_params_deinit(mc->dh_params);

567

992

return -1;

568

993

}

569

994

995

__attribute__((nonnull, warn_unused_result))

570

996

static int init_gnutls_session(gnutls_session_t *session,

571

997

mandos_context *mc){

572

998

int ret;

573

999

/* GnuTLS session creation */

574

1000

do {

575

ret = gnutls_init(session, GNUTLS_SERVER);

1001

ret = gnutls_init(session, (GNUTLS_SERVER

1002

#if GNUTLS_VERSION_NUMBER >= 0x030506

1003

| GNUTLS_NO_TICKETS

1004

#endif

1005

#if GNUTLS_VERSION_NUMBER >= 0x030606

1006

| GNUTLS_ENABLE_RAWPK

1007

#endif

1008

));

576

1009

if(quit_now){

577

1010

return -1;

578

1011

}

619

1052

/* ignore client certificate if any. */

620

1053

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

621

1054

622

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

623

624

1055

return 0;

625

1056

}

626

1057

628

1059

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

629

1060

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

630

1061

1062

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

1063

__attribute__((nonnull, warn_unused_result))

1064

static bool add_delete_local_route(const bool add,

1065

const char *address,

1066

AvahiIfIndex if_index){

1067

int ret;

1068

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

1069

char add_arg[] = "add";

1070

char delete_arg[] = "delete";

1071

char debug_flag[] = "--debug";

1072

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

1073

if(pluginhelperdir == NULL){

1074

if(debug){

1075

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

1076

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

1077

}

1078

return false;

1079

}

1080

1081

char interface[IF_NAMESIZE];

1082

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

1083

perror_plus("if_indextoname");

1084

return false;

1085

}

1086

1087

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

1088

if(devnull == -1){

1089

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

1090

return false;

1091

}

1092

pid_t pid = fork();

1093

if(pid == 0){

1094

/* Child */

1095

/* Raise privileges */

1096

errno = raise_privileges_permanently();

1097

if(errno != 0){

1098

perror_plus("Failed to raise privileges");

1099

/* _exit(EX_NOPERM); */

1100

} else {

1101

/* Set group */

1102

errno = 0;

1103

ret = setgid(0);

1104

if(ret == -1){

1105

perror_plus("setgid");

1106

close(devnull);

1107

_exit(EX_NOPERM);

1108

}

1109

/* Reset supplementary groups */

1110

errno = 0;

1111

ret = setgroups(0, NULL);

1112

if(ret == -1){

1113

perror_plus("setgroups");

1114

close(devnull);

1115

_exit(EX_NOPERM);

1116

}

1117

}

1118

ret = dup2(devnull, STDIN_FILENO);

1119

if(ret == -1){

1120

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

1121

close(devnull);

1122

_exit(EX_OSERR);

1123

}

1124

ret = close(devnull);

1125

if(ret == -1){

1126

perror_plus("close");

1127

}

1128

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1129

if(ret == -1){

1130

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

1131

_exit(EX_OSERR);

1132

}

1133

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

1134

O_RDONLY

1135

| O_DIRECTORY

1136

| O_PATH

1137

| O_CLOEXEC));

1138

if(helperdir_fd == -1){

1139

perror_plus("open");

1140

_exit(EX_UNAVAILABLE);

1141

}

1142

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

1143

helper, O_RDONLY));

1144

if(helper_fd == -1){

1145

perror_plus("openat");

1146

close(helperdir_fd);

1147

_exit(EX_UNAVAILABLE);

1148

}

1149

close(helperdir_fd);

1150

#ifdef __GNUC__

1151

#pragma GCC diagnostic push

1152

#pragma GCC diagnostic ignored "-Wcast-qual"

1153

#endif

1154

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

1155

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

1156

interface, debug ? debug_flag : NULL, NULL },

1157

environ) == -1){

1158

#ifdef __GNUC__

1159

#pragma GCC diagnostic pop

1160

#endif

1161

perror_plus("fexecve");

1162

_exit(EXIT_FAILURE);

1163

}

1164

}

1165

if(pid == -1){

1166

perror_plus("fork");

1167

close(devnull);

1168

return false;

1169

}

1170

ret = close(devnull);

1171

if(ret == -1){

1172

perror_plus("close");

1173

}

1174

int status;

1175

pid_t pret = -1;

1176

errno = 0;

1177

do {

1178

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

1179

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

1180

int errno_raising = 0;

1181

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

1182

errno_raising = errno;

1183

perror_plus("Failed to raise privileges in order to"

1184

" kill helper program");

1185

}

1186

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

1187

perror_plus("kill");

1188

}

1189

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

1190

perror_plus("Failed to lower privileges after killing"

1191

" helper program");

1192

}

1193

return false;

1194

}

1195

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

1196

if(pret == -1){

1197

perror_plus("waitpid");

1198

return false;

1199

}

1200

if(WIFEXITED(status)){

1201

if(WEXITSTATUS(status) != 0){

1202

fprintf_plus(stderr, "Error: iprouteadddel exited"

1203

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

1204

return false;

1205

}

1206

return true;

1207

}

1208

if(WIFSIGNALED(status)){

1209

fprintf_plus(stderr, "Error: iprouteadddel died by"

1210

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

1211

return false;

1212

}

1213

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

1214

return false;

1215

}

1216

1217

__attribute__((nonnull, warn_unused_result))

1218

static bool add_local_route(const char *address,

1219

AvahiIfIndex if_index){

1220

if(debug){

1221

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

1222

}

1223

return add_delete_local_route(true, address, if_index);

1224

}

1225

1226

__attribute__((nonnull, warn_unused_result))

1227

static bool delete_local_route(const char *address,

1228

AvahiIfIndex if_index){

1229

if(debug){

1230

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

1231

}

1232

return add_delete_local_route(false, address, if_index);

1233

}

1234

631

1235

/* Called when a Mandos server is found */

1236

__attribute__((nonnull, warn_unused_result))

632

1237

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

633

1238

AvahiIfIndex if_index,

634

1239

int af, mandos_context *mc){

643

1248

int retval = -1;

644

1249

gnutls_session_t session;

645

1250

int pf; /* Protocol family */

1251

bool route_added = false;

646

1252

647

1253

errno = 0;

648

1254

670

1276

bool match = false;

671

1277

{

672

1278

char *interface = NULL;

673

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

674

interface))){

1279

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

1280

mc->interfaces_size,

1281

interface))){

675

1282

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

676

1283

match = true;

677

1284

break;

706

1313

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

707

1314

}

708

1315

709

tcp_sd = socket(pf, SOCK_STREAM, 0);

1316

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

710

1317

if(tcp_sd < 0){

711

1318

int e = errno;

712

1319

perror_plus("socket");

719

1326

goto mandos_end;

720

1327

}

721

1328

722

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

723

1329

if(af == AF_INET6){

724

((struct sockaddr_in6 *)&to)->sin6_family = (sa_family_t)af;

725

ret = inet_pton(af, ip, &((struct sockaddr_in6 *)&to)->sin6_addr);

1330

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

1331

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

1332

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

726

1333

} else { /* IPv4 */

727

((struct sockaddr_in *)&to)->sin_family = (sa_family_t)af;

728

ret = inet_pton(af, ip, &((struct sockaddr_in *)&to)->sin_addr);

1334

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

1335

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

1336

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

729

1337

}

730

1338

if(ret < 0 ){

731

1339

int e = errno;

740

1348

goto mandos_end;

741

1349

}

742

1350

if(af == AF_INET6){

743

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

1351

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

744

1352

if(IN6_IS_ADDR_LINKLOCAL

745

1353

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

746

1354

if(if_index == AVAHI_IF_UNSPEC){

801

1409

goto mandos_end;

802

1410

}

803

1411

804

if(af == AF_INET6){

805

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

806

sizeof(struct sockaddr_in6));

807

} else {

808

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

809

sizeof(struct sockaddr_in));

810

}

811

if(ret < 0){

812

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

813

int e = errno;

814

perror_plus("connect");

815

errno = e;

816

}

817

goto mandos_end;

818

}

819

820

if(quit_now){

821

errno = EINTR;

822

goto mandos_end;

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;

823

1467

}

824

1468

825

1469

const char *out = mandos_protocol_version;

979

1623

&decrypted_buffer, mc);

980

1624

if(decrypted_buffer_size >= 0){

981

1625

1626

clearerr(stdout);

982

1627

written = 0;

983

1628

while(written < (size_t) decrypted_buffer_size){

984

1629

if(quit_now){

1000

1645

}

1001

1646

written += (size_t)ret;

1002

1647

}

1648

ret = fflush(stdout);

1649

if(ret != 0){

1650

int e = errno;

1651

if(debug){

1652

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

1653

strerror(errno));

1654

}

1655

errno = e;

1656

goto mandos_end;

1657

}

1003

1658

retval = 0;

1004

1659

}

1005

1660

}

1008

1663

1009

1664

mandos_end:

1010

1665

{

1666

if(route_added){

1667

if(not delete_local_route(ip, if_index)){

1668

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

1669

" interface %d", ip, if_index);

1670

}

1671

}

1011

1672

int e = errno;

1012

1673

free(decrypted_buffer);

1013

1674

free(buffer);

1014

1675

if(tcp_sd >= 0){

1015

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

1676

ret = close(tcp_sd);

1016

1677

}

1017

1678

if(ret == -1){

1018

1679

if(e == 0){

1043

1704

AVAHI_GCC_UNUSED AvahiStringList *txt,

1044

1705

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1045

1706

flags,

1046

void* mc){

1707

void *mc){

1047

1708

if(r == NULL){

1048

1709

return;

1049

1710

}

1052

1713

timed out */

1053

1714

1054

1715

if(quit_now){

1716

avahi_s_service_resolver_free(r);

1055

1717

return;

1056

1718

}

1057

1719

1102

1764

const char *domain,

1103

1765

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1104

1766

flags,

1105

void* mc){

1767

void *mc){

1106

1768

if(b == NULL){

1107

1769

return;

1108

1770

}

1168

1830

errno = old_errno;

1169

1831

}

1170

1832

1833

__attribute__((nonnull, warn_unused_result))

1171

1834

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

1172

1835

int ret;

1173

error_t ret_errno;

1836

int old_errno;

1174

1837

1175

1838

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

1176

1839

if(s < 0){

1177

ret_errno = errno;

1840

old_errno = errno;

1178

1841

perror_plus("socket");

1179

errno = ret_errno;

1842

errno = old_errno;

1180

1843

return false;

1181

1844

}

1182

strcpy(ifr->ifr_name, ifname);

1845

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

1846

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

1183

1847

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1184

1848

if(ret == -1){

1185

1849

if(debug){

1186

ret_errno = errno;

1850

old_errno = errno;

1187

1851

perror_plus("ioctl SIOCGIFFLAGS");

1188

errno = ret_errno;

1852

errno = old_errno;

1853

}

1854

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

1855

old_errno = errno;

1856

perror_plus("close");

1857

errno = old_errno;

1189

1858

}

1190

1859

return false;

1191

1860

}

1861

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

1862

old_errno = errno;

1863

perror_plus("close");

1864

errno = old_errno;

1865

}

1192

1866

return true;

1193

1867

}

1194

1868

1869

__attribute__((nonnull, warn_unused_result))

1195

1870

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

1196

1871

1197

1872

/* Reject the loopback device */

1239

1914

* corresponds to an acceptable network device.

1240

1915

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

1241

1916

*/

1917

__attribute__((nonnull, warn_unused_result))

1242

1918

int good_interface(const struct dirent *if_entry){

1243

1919

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

1244

1920

return 0;

1262

1938

/*

1263

1939

* This function determines if a network interface is up.

1264

1940

*/

1941

__attribute__((nonnull, warn_unused_result))

1265

1942

bool interface_is_up(const char *interface){

1266

1943

struct ifreq ifr;

1267

1944

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

1278

1955

/*

1279

1956

* This function determines if a network interface is running

1280

1957

*/

1958

__attribute__((nonnull, warn_unused_result))

1281

1959

bool interface_is_running(const char *interface){

1282

1960

struct ifreq ifr;

1283

1961

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

1291

1969

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

1292

1970

}

1293

1971

1972

__attribute__((nonnull, pure, warn_unused_result))

1294

1973

int notdotentries(const struct dirent *direntry){

1295

1974

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

1296

1975

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

1303

1982

}

1304

1983

1305

1984

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

1985

__attribute__((nonnull, warn_unused_result))

1306

1986

int runnable_hook(const struct dirent *direntry){

1307

1987

int ret;

1308

1988

size_t sret;

1316

1996

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

1317

1997

"abcdefghijklmnopqrstuvwxyz"

1318

1998

"0123456789"

1319

"_-");

1999

"_.-");

1320

2000

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

1321

2001

/* Contains non-allowed characters */

1322

2002

if(debug){

1326

2006

return 0;

1327

2007

}

1328

2008

1329

char *fullname = NULL;

1330

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

1331

if(ret < 0){

1332

perror_plus("asprintf");

1333

return 0;

1334

}

1335

1336

ret = stat(fullname, &st);

2009

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

1337

2010

if(ret == -1){

1338

2011

if(debug){

1339

2012

perror_plus("Could not stat hook");

1363

2036

return 1;

1364

2037

}

1365

2038

2039

__attribute__((nonnull, warn_unused_result))

1366

2040

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1367

2041

mandos_context *mc){

1368

2042

int ret;

1372

2046

1373

2047

while(true){

1374

2048

if(mc->current_server == NULL){

1375

if (debug){

2049

if(debug){

1376

2050

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

1377

2051

" No timeout!\n");

1378

2052

}

1379

2053

ret = avahi_simple_poll_iterate(s, -1);

1380

2054

} else {

1381

if (debug){

2055

if(debug){

1382

2056

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

1383

2057

" it, or wait\n");

1384

2058

}

1401

2075

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

1402

2076

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

1403

2077

1404

if (debug){

2078

if(debug){

1405

2079

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

1406

2080

block_time);

1407

2081

}

1429

2103

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

1430

2104

}

1431

2105

if(ret != 0){

1432

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

2106

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

1433

2107

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

1434

2108

}

1435

2109

}

1436

2110

}

1437

2111

}

1438

2112

1439

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

1440

error_t raise_privileges(void){

1441

error_t old_errno = errno;

1442

error_t ret_errno = 0;

1443

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

1444

ret_errno = errno;

1445

perror_plus("seteuid");

1446

}

1447

errno = old_errno;

1448

return ret_errno;

1449

}

1450

1451

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

1452

error_t raise_privileges_permanently(void){

1453

error_t old_errno = errno;

1454

error_t ret_errno = raise_privileges();

1455

if(ret_errno != 0){

1456

errno = old_errno;

1457

return ret_errno;

1458

}

1459

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

1460

ret_errno = errno;

1461

perror_plus("seteuid");

1462

}

1463

errno = old_errno;

1464

return ret_errno;

1465

}

1466

1467

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

1468

error_t lower_privileges(void){

1469

error_t old_errno = errno;

1470

error_t ret_errno = 0;

1471

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

1472

ret_errno = errno;

1473

perror_plus("seteuid");

1474

}

1475

errno = old_errno;

1476

return ret_errno;

1477

}

1478

1479

/* Lower privileges permanently */

1480

error_t lower_privileges_permanently(void){

1481

error_t old_errno = errno;

1482

error_t ret_errno = 0;

1483

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

1484

ret_errno = errno;

1485

perror_plus("setuid");

1486

}

1487

errno = old_errno;

1488

return ret_errno;

1489

}

1490

1491

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

2113

__attribute__((nonnull))

2114

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

1492

2115

const float delay){

1493

struct dirent **direntries;

1494

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

1495

alphasort);

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);

1496

2139

if(numhooks == -1){

1497

if(errno == ENOENT){

1498

if(debug){

1499

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

1500

" found\n", hookdir);

1501

}

1502

} else {

1503

perror_plus("scandir");

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);

1504

2151

}

1505

} else {

1506

struct dirent *direntry;

1507

int ret;

1508

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

1509

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

1510

direntry = direntries[i];

1511

char *fullname = NULL;

1512

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

1513

if(ret < 0){

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){

1514

2198

perror_plus("asprintf");

1515

continue;

1516

}

1517

if(debug){

1518

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

1519

direntry->d_name);

1520

}

1521

pid_t hook_pid = fork();

1522

if(hook_pid == 0){

1523

/* Child */

1524

/* Raise privileges */

1525

raise_privileges_permanently();

1526

/* Set group */

1527

errno = 0;

1528

ret = setgid(0);

1529

if(ret == -1){

1530

perror_plus("setgid");

1531

}

1532

/* Reset supplementary groups */

1533

errno = 0;

1534

ret = setgroups(0, NULL);

1535

if(ret == -1){

1536

perror_plus("setgroups");

1537

}

1538

dup2(devnull, STDIN_FILENO);

1539

close(devnull);

1540

dup2(STDERR_FILENO, STDOUT_FILENO);

1541

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

1542

if(ret == -1){

1543

perror_plus("setenv");

1544

_exit(EX_OSERR);

1545

}

1546

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

1547

if(ret == -1){

1548

perror_plus("setenv");

1549

_exit(EX_OSERR);

1550

}

1551

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

1552

if(ret == -1){

1553

perror_plus("setenv");

1554

_exit(EX_OSERR);

1555

}

1556

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

1557

if(ret == -1){

1558

perror_plus("setenv");

1559

_exit(EX_OSERR);

1560

}

1561

char *delaystring;

1562

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

1563

if(ret == -1){

1564

perror_plus("asprintf");

1565

_exit(EX_OSERR);

1566

}

1567

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

1568

if(ret == -1){

1569

free(delaystring);

1570

perror_plus("setenv");

1571

_exit(EX_OSERR);

1572

}

2199

_exit(EX_OSERR);

2200

}

2201

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

2202

if(ret == -1){

1573

2203

free(delaystring);

1574

if(connect_to != NULL){

1575

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

1576

if(ret == -1){

1577

perror_plus("setenv");

1578

_exit(EX_OSERR);

1579

}

1580

}

1581

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

1582

perror_plus("execl");

1583

_exit(EXIT_FAILURE);

1584

}

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;

1585

2272

} else {

1586

int status;

1587

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

1588

perror_plus("waitpid");

1589

free(fullname);

1590

continue;

1591

}

1592

if(WIFEXITED(status)){

1593

if(WEXITSTATUS(status) != 0){

1594

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

1595

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

1596

WEXITSTATUS(status));

1597

free(fullname);

1598

continue;

1599

}

1600

} else if(WIFSIGNALED(status)){

1601

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

1602

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

1603

WTERMSIG(status));

1604

free(fullname);

1605

continue;

1606

} else {

1607

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

1608

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

1609

free(fullname);

1610

continue;

1611

}

1612

}

1613

free(fullname);

1614

if(debug){

1615

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

1616

direntry->d_name);

1617

}

1618

}

1619

close(devnull);

1620

}

1621

return true;

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);

1622

2292

}

1623

2293

1624

error_t bring_up_interface(const char *const interface,

1625

const float delay){

1626

int sd = -1;

1627

error_t old_errno = errno;

1628

error_t ret_errno = 0;

1629

int ret, ret_setflags;

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;

1630

2299

struct ifreq network;

1631

2300

unsigned int if_index = if_nametoindex(interface);

1632

2301

if(if_index == 0){

1641

2310

}

1642

2311

1643

2312

if(not interface_is_up(interface)){

1644

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

2313

int ret_errno = 0;

2314

int ioctl_errno = 0;

2315

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

1645

2316

ret_errno = errno;

1646

2317

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

1647

2318

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

2319

errno = old_errno;

1648

2320

return ret_errno;

1649

2321

}

1650

network.ifr_flags |= IFF_UP;

2322

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

1651

2323

1652

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1653

if(sd < 0){

2324

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

2325

if(sd == -1){

1654

2326

ret_errno = errno;

1655

2327

perror_plus("socket");

1656

2328

errno = old_errno;

1657

2329

return ret_errno;

1658

2330

}

1659

2331

1660

2332

if(quit_now){

1661

close(sd);

2333

ret = close(sd);

2334

if(ret == -1){

2335

perror_plus("close");

2336

}

1662

2337

errno = old_errno;

1663

2338

return EINTR;

1664

2339

}

1668

2343

interface);

1669

2344

}

1670

2345

1671

/* Raise priviliges */

1672

raise_privileges();

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

}

1673

2352

1674

2353

#ifdef __linux__

1675

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1676

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

1677

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

1678

bool restore_loglevel = true;

1679

if(ret_linux == -1){

1680

restore_loglevel = false;

1681

perror_plus("klogctl");

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

}

1682

2365

}

1683

2366

#endif /* __linux__ */

1684

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

1685

ret_errno = errno;

2367

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

2368

ioctl_errno = errno;

1686

2369

#ifdef __linux__

1687

2370

if(restore_loglevel){

1688

2371

ret_linux = klogctl(7, NULL, 0);

1692

2375

}

1693

2376

#endif /* __linux__ */

1694

2377

1695

/* Lower privileges */

1696

lower_privileges();

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

}

1697

2387

1698

2388

/* Close the socket */

1699

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

2389

ret = close(sd);

1700

2390

if(ret == -1){

1701

2391

perror_plus("close");

1702

2392

}

1703

2393

1704

2394

if(ret_setflags == -1){

1705

errno = ret_errno;

2395

errno = ioctl_errno;

1706

2396

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1707

2397

errno = old_errno;

1708

return ret_errno;

2398

return ioctl_errno;

1709

2399

}

1710

2400

} else if(debug){

1711

2401

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

1714

2404

1715

2405

/* Sleep checking until interface is running.

1716

2406

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

1717

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

2407

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

1718

2408

if(interface_is_running(interface)){

1719

2409

break;

1720

2410

}

1729

2419

return 0;

1730

2420

}

1731

2421

1732

error_t take_down_interface(const char *const interface){

1733

error_t old_errno = errno;

2422

__attribute__((nonnull, warn_unused_result))

2423

int take_down_interface(const char *const interface){

2424

int old_errno = errno;

1734

2425

struct ifreq network;

1735

2426

unsigned int if_index = if_nametoindex(interface);

1736

2427

if(if_index == 0){

1739

2430

return ENXIO;

1740

2431

}

1741

2432

if(interface_is_up(interface)){

1742

error_t ret_errno = 0;

2433

int ret_errno = 0;

2434

int ioctl_errno = 0;

1743

2435

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

1744

2436

ret_errno = errno;

1745

2437

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

1746

2438

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

2439

errno = old_errno;

1747

2440

return ret_errno;

1748

2441

}

1749

2442

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

1750

2443

1751

2444

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

1752

if(sd < 0){

2445

if(sd == -1){

1753

2446

ret_errno = errno;

1754

2447

perror_plus("socket");

1755

2448

errno = old_errno;

1761

2454

interface);

1762

2455

}

1763

2456

1764

/* Raise priviliges */

1765

raise_privileges();

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

}

1766

2463

1767

2464

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

1768

ret_errno = errno;

2465

ioctl_errno = errno;

1769

2466

1770

/* Lower privileges */

1771

lower_privileges();

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

}

1772

2476

1773

2477

/* Close the socket */

1774

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

2478

int ret = close(sd);

1775

2479

if(ret == -1){

1776

2480

perror_plus("close");

1777

2481

}

1778

2482

1779

2483

if(ret_setflags == -1){

1780

errno = ret_errno;

2484

errno = ioctl_errno;

1781

2485

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1782

2486

errno = old_errno;

1783

return ret_errno;

2487

return ioctl_errno;

1784

2488

}

1785

2489

} else if(debug){

1786

2490

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

1792

2496

}

1793

2497

1794

2498

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

1795

mandos_context mc = { .server = NULL, .dh_bits = 1024,

1796

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

1797

"+CTYPE-OPENPGP", .current_server = NULL,

1798

.interfaces = NULL, .interfaces_size = 0 };

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 };

1799

2512

AvahiSServiceBrowser *sb = NULL;

1800

2513

error_t ret_errno;

1801

2514

int ret;

1804

2517

int exitcode = EXIT_SUCCESS;

1805

2518

char *interfaces_to_take_down = NULL;

1806

2519

size_t interfaces_to_take_down_size = 0;

1807

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

1808

bool tempdir_created = false;

2520

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

2521

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

2522

char *tempdir = NULL;

1809

2523

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1810

2524

const char *seckey = PATHDIR "/" SECKEY;

1811

2525

const char *pubkey = PATHDIR "/" PUBKEY;

2526

#if GNUTLS_VERSION_NUMBER >= 0x030606

2527

const char *tls_privkey = PATHDIR "/" TLS_PRIVKEY;

2528

const char *tls_pubkey = PATHDIR "/" TLS_PUBKEY;

2529

#endif

2530

const char *dh_params_file = NULL;

1812

2531

char *interfaces_hooks = NULL;

1813

2532

1814

2533

bool gnutls_initialized = false;

1861

2580

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

1862

2581

.arg = "FILE",

1863

2582

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

1864

.group = 2 },

2583

.group = 1 },

2584

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

2585

.arg = "FILE",

2586

#if GNUTLS_VERSION_NUMBER >= 0x030606

2587

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

2588

#else

2589

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

2590

#endif

2591

.group = 1 },

2592

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

2593

.arg = "FILE",

2594

#if GNUTLS_VERSION_NUMBER >= 0x030606

2595

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

2596

#else

2597

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

2598

#endif

2599

.group = 1 },

1865

2600

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

1866

2601

.arg = "BITS",

1867

2602

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

1868

2603

" Diffie-Hellman key exchange",

1869

2604

.group = 2 },

2605

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

2606

.arg = "FILE",

2607

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

2608

" for the Diffie-Hellman key exchange",

2609

.group = 2 },

1870

2610

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

1871

2611

.arg = "STRING",

1872

2612

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

1918

2658

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

1919

2659

pubkey = arg;

1920

2660

break;

2661

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

2662

#if GNUTLS_VERSION_NUMBER >= 0x030606

2663

tls_privkey = arg;

2664

#endif

2665

break;

2666

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

2667

#if GNUTLS_VERSION_NUMBER >= 0x030606

2668

tls_pubkey = arg;

2669

#endif

2670

break;

1921

2671

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

1922

2672

errno = 0;

1923

2673

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

1927

2677

}

1928

2678

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

1929

2679

break;

2680

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

2681

dh_params_file = arg;

2682

break;

1930

2683

case 130: /* --priority */

1931

2684

mc.priority = arg;

1932

2685

break;

1955

2708

argp_state_help(state, state->out_stream,

1956

2709

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

1957

2710

& ~(unsigned int)ARGP_HELP_EXIT_OK);

2711

__builtin_unreachable();

1958

2712

case -3: /* --usage */

1959

2713

argp_state_help(state, state->out_stream,

1960

2714

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2715

__builtin_unreachable();

1961

2716

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

1962

2717

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

1963

2718

exit(argp_err_exit_status);

1972

2727

.args_doc = "",

1973

2728

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

1974

2729

" passwords from a Mandos server" };

1975

ret = argp_parse(&argp, argc, argv,

1976

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1977

switch(ret){

2730

ret_errno = argp_parse(&argp, argc, argv,

2731

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2732

switch(ret_errno){

1978

2733

case 0:

1979

2734

break;

1980

2735

case ENOMEM:

1981

2736

default:

1982

errno = ret;

2737

errno = ret_errno;

1983

2738

perror_plus("argp_parse");

1984

2739

exitcode = EX_OSERR;

1985

2740

goto end;

1988

2743

goto end;

1989

2744

}

1990

2745

}

1991

2746

1992

2747

{

1993

/* Work around Debian bug #633582:

1994

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

1995

1996

/* Re-raise priviliges */

1997

if(raise_privileges() == 0){

2748

/* Re-raise privileges */

2749

ret = raise_privileges();

2750

if(ret != 0){

2751

errno = ret;

2752

perror_plus("Failed to raise privileges");

2753

} else {

1998

2754

struct stat st;

1999

2755

2756

/* Work around Debian bug #633582:

2757

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

2758

2000

2759

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

2001

2760

int seckey_fd = open(seckey, O_RDONLY);

2002

2761

if(seckey_fd == -1){

2014

2773

}

2015

2774

}

2016

2775

}

2017

TEMP_FAILURE_RETRY(close(seckey_fd));

2776

close(seckey_fd);

2018

2777

}

2019

2778

}

2020

2779

2021

2780

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

2022

2781

int pubkey_fd = open(pubkey, O_RDONLY);

2023

2782

if(pubkey_fd == -1){

2035

2794

}

2036

2795

}

2037

2796

}

2038

TEMP_FAILURE_RETRY(close(pubkey_fd));

2039

}

2040

}

2041

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

2042

2832

/* Lower privileges */

2043

lower_privileges();

2833

ret = lower_privileges();

2834

if(ret != 0){

2835

errno = ret;

2836

perror_plus("Failed to lower privileges");

2837

}

2044

2838

}

2045

2839

}

2046

2840

2072

2866

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

2073

2867

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

2074

2868

}

2075

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

2076

interfaces_hooks : "", delay)){

2077

goto end;

2078

}

2869

run_network_hooks("start", interfaces_hooks != NULL ?

2870

interfaces_hooks : "", delay);

2079

2871

}

2080

2872

2081

2873

if(not debug){

2159

2951

2160

2952

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

2161

2953

if(mc.interfaces == NULL){

2162

struct dirent **direntries;

2954

struct dirent **direntries = NULL;

2163

2955

/* Look for any good interfaces */

2164

2956

ret = scandir(sys_class_net, &direntries, good_interface,

2165

2957

alphasort);

2171

2963

if(ret_errno != 0){

2172

2964

errno = ret_errno;

2173

2965

perror_plus("argz_add");

2966

free(direntries[i]);

2174

2967

continue;

2175

2968

}

2176

2969

if(debug){

2177

2970

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

2178

2971

direntries[i]->d_name);

2179

2972

}

2973

free(direntries[i]);

2180

2974

}

2181

2975

free(direntries);

2182

2976

} else {

2183

free(direntries);

2977

if(ret == 0){

2978

free(direntries);

2979

}

2184

2980

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

2185

2981

exitcode = EXIT_FAILURE;

2186

2982

goto end;

2209

3005

break;

2210

3006

}

2211

3007

bool interface_was_up = interface_is_up(interface);

2212

ret = bring_up_interface(interface, delay);

3008

errno = bring_up_interface(interface, delay);

2213

3009

if(not interface_was_up){

2214

if(ret != 0){

2215

errno = ret;

2216

perror_plus("Failed to bring up interface");

3010

if(errno != 0){

3011

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

3012

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

2217

3013

} else {

2218

ret_errno = argz_add(&interfaces_to_take_down,

2219

&interfaces_to_take_down_size,

2220

interface);

2221

if(ret_errno != 0){

2222

errno = ret_errno;

3014

errno = argz_add(&interfaces_to_take_down,

3015

&interfaces_to_take_down_size,

3016

interface);

3017

if(errno != 0){

2223

3018

perror_plus("argz_add");

2224

3019

}

2225

3020

}

2243

3038

goto end;

2244

3039

}

2245

3040

2246

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

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

2247

3048

if(ret == -1){

2248

3049

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

2249

3050

exitcode = EX_UNAVAILABLE;

2256

3057

goto end;

2257

3058

}

2258

3059

2259

if(mkdtemp(tempdir) == NULL){

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){

2260

3070

perror_plus("mkdtemp");

2261

3071

goto end;

2262

3072

}

2263

tempdir_created = true;

2264

3073

2265

3074

if(quit_now){

2266

3075

goto end;

2341

3150

sleep((unsigned int)retry_interval);

2342

3151

}

2343

3152

2344

if (not quit_now){

3153

if(not quit_now){

2345

3154

exitcode = EXIT_SUCCESS;

2346

3155

}

2347

3156

2363

3172

2364

3173

/* Allocate a new server */

2365

3174

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2366

&config, NULL, NULL, &ret_errno);

3175

&config, NULL, NULL, &ret);

2367

3176

2368

3177

/* Free the Avahi configuration data */

2369

3178

avahi_server_config_free(&config);

2372

3181

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

2373

3182

if(mc.server == NULL){

2374

3183

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

2375

avahi_strerror(ret_errno));

3184

avahi_strerror(ret));

2376

3185

exitcode = EX_UNAVAILABLE;

2377

3186

goto end;

2378

3187

}

2402

3211

if(debug){

2403

3212

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

2404

3213

}

2405

3214

2406

3215

ret = avahi_loop_with_timeout(simple_poll,

2407

3216

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

2408

3217

if(debug){

2413

3222

end:

2414

3223

2415

3224

if(debug){

2416

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

3225

if(signal_received){

3226

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

3227

argv[0], signal_received,

3228

strsignal(signal_received));

3229

} else {

3230

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

3231

}

2417

3232

}

2418

3233

2419

3234

/* Cleanup things */

2430

3245

2431

3246

if(gnutls_initialized){

2432

3247

gnutls_certificate_free_credentials(mc.cred);

2433

gnutls_global_deinit();

2434

3248

gnutls_dh_params_deinit(mc.dh_params);

2435

3249

}

2436

3250

2444

3258

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

2445

3259

while(mc.current_server != NULL){

2446

3260

server *next = mc.current_server->next;

3261

#ifdef __GNUC__

3262

#pragma GCC diagnostic push

3263

#pragma GCC diagnostic ignored "-Wcast-qual"

3264

#endif

3265

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

3266

#ifdef __GNUC__

3267

#pragma GCC diagnostic pop

3268

#endif

2447

3269

free(mc.current_server);

2448

3270

mc.current_server = next;

2449

3271

}

2450

3272

}

2451

3273

2452

/* Re-raise priviliges */

3274

/* Re-raise privileges */

2453

3275

{

2454

raise_privileges();

2455

2456

/* Run network hooks */

2457

run_network_hooks("stop", interfaces_hooks != NULL ?

2458

interfaces_hooks : "", delay);

2459

2460

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

2461

{

2462

char *interface = NULL;

2463

while((interface=argz_next(interfaces_to_take_down,

2464

interfaces_to_take_down_size,

2465

interface))){

2466

ret_errno = take_down_interface(interface);

2467

if(ret_errno != 0){

2468

errno = ret_errno;

2469

perror_plus("Failed to take down interface");

2470

}

2471

}

2472

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

2473

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

2474

" down\n");

2475

}

2476

}

2477

2478

lower_privileges_permanently();

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

}

2479

3310

}

2480

3311

2481

3312

free(interfaces_to_take_down);

2482

3313

free(interfaces_hooks);

2483

3314

3315

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

3316

uintmax_t level){

3317

struct dirent **direntries = NULL;

3318

int dret;

3319

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

3320

O_RDONLY

3321

| O_NOFOLLOW

3322

| O_DIRECTORY

3323

| O_PATH));

3324

if(dir_fd == -1){

3325

perror_plus("open");

3326

return;

3327

}

3328

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

3329

notdotentries, alphasort);

3330

if(numentries >= 0){

3331

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

3332

if(debug){

3333

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

3334

dirname, direntries[i]->d_name);

3335

}

3336

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

3337

if(dret == -1){

3338

if(errno == EISDIR){

3339

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

3340

AT_REMOVEDIR);

3341

}

3342

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

3343

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

3344

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

3345

/* Recurse only in this special case */

3346

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

3347

dret = 0;

3348

}

3349

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

3350

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

3351

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

3352

}

3353

}

3354

free(direntries[i]);

3355

}

3356

3357

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

3358

free(direntries);

3359

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3360

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

3361

perror_plus("rmdir");

3362

}

3363

} else {

3364

perror_plus("scandirat");

3365

}

3366

close(dir_fd);

3367

}

3368

2484

3369

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

2485

if(tempdir_created){

2486

struct dirent **direntries = NULL;

2487

struct dirent *direntry = NULL;

2488

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

2489

alphasort);

2490

if (numentries > 0){

2491

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

2492

direntry = direntries[i];

2493

char *fullname = NULL;

2494

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

2495

direntry->d_name);

2496

if(ret < 0){

2497

perror_plus("asprintf");

2498

continue;

2499

}

2500

ret = remove(fullname);

2501

if(ret == -1){

2502

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

2503

strerror(errno));

2504

}

2505

free(fullname);

2506

}

2507

}

2508

2509

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

2510

free(direntries);

2511

if (numentries == -1){

2512

perror_plus("scandir");

2513

}

2514

ret = rmdir(tempdir);

2515

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

2516

perror_plus("rmdir");

2517

}

3370

if(tempdir != NULL){

3371

clean_dir_at(-1, tempdir, 0);

2518

3372

}

2519

3373

2520

3374

if(quit_now){