/mandos/release : revision 237.16.17

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

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*

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* Everything else is

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*

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* This file is part of Mandos.

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*

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

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

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

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* (at your option) any later version.

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*

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

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*

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

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

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

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

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*

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

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* WITHOUT ANY WARRANTY; without even the implied warranty of

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

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* General Public License for more details.

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*

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

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

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* along with this program. If not, see

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

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*

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

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*/

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

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#ifndef _LARGEFILE_SOURCE

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#define _LARGEFILE_SOURCE

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#endif /* not _LARGEFILE_SOURCE */

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#endif

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#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

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#endif /* not _FILE_OFFSET_BITS */

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#endif

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

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

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stdout, ferror() */

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

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stdout, ferror(), remove() */

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

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

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

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strtof(), abort() */

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

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

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asprintf(), strncpy(), strsignal()

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*/

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

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

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

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

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sockaddr_in6, PF_INET6,

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opendir(), DIR */

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

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

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inet_pton(), connect(),

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getnameinfo() */

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

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inet_pton(), connect() */

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

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

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*/

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

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strtoimax() */

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

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EAI_SYSTEM, ENETUNREACH,

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EHOSTUNREACH, ECONNREFUSED, EPROTO,

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EIO, ENOENT, ENXIO, ENOMEM, EISDIR,

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ENOTEMPTY,

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

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

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program_invocation_short_name */

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

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

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*/

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

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

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

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unlinkat() */

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

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setgid(), pause(), _exit() */

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

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

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

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argp_state, struct argp,

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

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WEXITSTATUS(), WTERMSIG() */

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

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

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argz_delete(), argz_append(),

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argz_stringify(), argz_add(),

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argz_count() */

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

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EAI_SYSTEM, gai_strerror() */

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#ifdef __linux__

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

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

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char *connect_to = NULL;

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const char *hookdir = HOOKDIR;

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int hookdir_fd = -1;

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uid_t uid = 65534;

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gid_t gid = 65534;

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

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typedef struct server{

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const char *ip;

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in_port_t port;

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uint16_t port;

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AvahiIfIndex if_index;

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int af;

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struct timespec last_seen;

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

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typedef struct {

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AvahiSimplePoll *simple_poll;

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AvahiServer *server;

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gnutls_certificate_credentials_t cred;

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unsigned int dh_bits;

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const char *priority;

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gpgme_ctx_t ctx;

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server *current_server;

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char *interfaces;

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size_t interfaces_size;

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} mandos_context;

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/* global so signal handler can reach it*/

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AvahiSimplePoll *simple_poll;

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

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

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.dh_bits = 1024, .priority = "SECURE256"

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

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.current_server = NULL };

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sig_atomic_t quit_now = 0;

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int signal_received = 0;

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/* Function to use when printing errors */

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void perror_plus(const char *print_text){

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int e = errno;

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

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program_invocation_short_name);

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errno = e;

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perror(print_text);

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}

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

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

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va_list ap;

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va_start (ap, format);

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

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program_invocation_short_name));

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

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

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}

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/*

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

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* "buffer_length" is how much is already used.

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*/

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__attribute__((nonnull, warn_unused_result))

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size_t incbuffer(char **buffer, size_t buffer_length,

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size_t buffer_capacity){

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if(buffer_length + BUFFER_SIZE > buffer_capacity){

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

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if(new_buf == NULL){

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int old_errno = errno;

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free(*buffer);

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errno = old_errno;

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*buffer = NULL;

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

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if(buffer == NULL){

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return 0;

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}

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*buffer = new_buf;

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buffer_capacity += BUFFER_SIZE;

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200

}

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return buffer_capacity;

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202

}

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

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__attribute__((nonnull, warn_unused_result))

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

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int af, server **current_server){

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

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int af){

231

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int ret;

232

208

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

233

209

if(new_server == NULL){

234

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perror_plus("malloc");

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return false;

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return -1;

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212

}

237

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

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.port = port,

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.af = af };

241

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if(new_server->ip == NULL){

242

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perror_plus("strdup");

243

free(new_server);

244

return false;

245

}

246

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

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if(ret == -1){

248

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"

252

#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);

258

return false;

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return -1;

259

220

}

260

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/* Special case of first server */

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if(*current_server == NULL){

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if (mc.current_server == NULL){

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new_server->next = new_server;

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new_server->prev = new_server;

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*current_server = new_server;

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mc.current_server = new_server;

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

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} else {

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

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new_server->next = *current_server;

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

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new_server->next = mc.current_server;

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

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new_server->prev->next = new_server;

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(*current_server)->prev = new_server;

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}

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return true;

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mc.current_server->prev = new_server;

232

}

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

234

if(ret == -1){

235

perror_plus("clock_gettime");

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return -1;

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}

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return 0;

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}

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240

275

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/*

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* Initialize GPGME.

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*/

278

__attribute__((nonnull, warn_unused_result))

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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){

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

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const char *tempdir){

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gpgme_error_t rc;

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gpgme_engine_info_t engine_info;

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/*

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

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*/

289

bool import_key(const char * const filename){

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bool import_key(const char *filename){

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int ret;

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int fd;

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gpgme_data_t pgp_data;

304

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return false;

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}

306

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

271

rc = gpgme_op_import(mc.ctx, pgp_data);

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if(rc != GPG_ERR_NO_ERROR){

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

312

276

}

313

{

314

gpgme_import_result_t import_result

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= gpgme_op_import_result(mc->ctx);

316

if((import_result->imported < 1

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or import_result->not_imported > 0)

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and import_result->unchanged == 0){

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

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fprintf_plus(stderr,

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

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import_result->considered);

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fprintf_plus(stderr,

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

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import_result->no_user_id);

326

fprintf_plus(stderr,

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

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import_result->imported);

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

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import_result->imported_rsa);

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

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import_result->unchanged);

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

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import_result->new_user_ids);

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

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import_result->new_sub_keys);

337

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

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import_result->new_signatures);

339

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

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import_result->new_revocations);

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fprintf_plus(stderr,

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

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import_result->secret_read);

344

fprintf_plus(stderr,

345

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

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import_result->secret_imported);

347

fprintf_plus(stderr,

348

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

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import_result->secret_unchanged);

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

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import_result->not_imported);

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for(gpgme_import_status_t import_status

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= import_result->imports;

354

import_status != NULL;

355

import_status = import_status->next){

356

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

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import_status->fpr);

358

if(import_status->result != GPG_ERR_NO_ERROR){

359

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

360

gpgme_strsource(import_status->result),

361

gpgme_strerror(import_status->result));

362

}

363

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

364

fprintf_plus(stderr,

365

import_status->status & GPGME_IMPORT_NEW

366

? "The key was new.\n"

367

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

368

fprintf_plus(stderr,

369

import_status->status & GPGME_IMPORT_UID

370

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

371

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

372

fprintf_plus(stderr,

373

import_status->status & GPGME_IMPORT_SIG

374

? "The key contained new signatures.\n"

375

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

376

fprintf_plus(stderr,

377

import_status->status & GPGME_IMPORT_SUBKEY

378

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

379

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

380

fprintf_plus(stderr,

381

import_status->status & GPGME_IMPORT_SECRET

382

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

383

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

384

}

385

return false;

386

}

387

}

388

277

389

ret = close(fd);

278

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

390

279

if(ret == -1){

391

280

perror_plus("close");

392

281

}

429

318

}

430

319

431

320

/* Create new GPGME "context" */

432

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

321

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

433

322

if(rc != GPG_ERR_NO_ERROR){

434

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

435

gpgme_strsource(rc), gpgme_strerror(rc));

323

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

324

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

325

gpgme_strerror(rc));

436

326

return false;

437

327

}

438

328

447

337

* Decrypt OpenPGP data.

448

338

* Returns -1 on error

449

339

*/

450

__attribute__((nonnull, warn_unused_result))

451

340

static ssize_t pgp_packet_decrypt(const char *cryptotext,

452

341

size_t crypto_size,

453

char **plaintext,

454

mandos_context *mc){

342

char **plaintext){

455

343

gpgme_data_t dh_crypto, dh_plain;

456

344

gpgme_error_t rc;

457

345

ssize_t ret;

474

362

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

475

363

rc = gpgme_data_new(&dh_plain);

476

364

if(rc != GPG_ERR_NO_ERROR){

477

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

365

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

366

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

478

367

gpgme_strsource(rc), gpgme_strerror(rc));

479

368

gpgme_data_release(dh_crypto);

480

369

return -1;

482

371

483

372

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

484

373

data buffer */

485

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

374

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

486

375

if(rc != GPG_ERR_NO_ERROR){

487

376

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

488

377

gpgme_strsource(rc), gpgme_strerror(rc));

489

378

plaintext_length = -1;

490

379

if(debug){

491

380

gpgme_decrypt_result_t result;

492

result = gpgme_op_decrypt_result(mc->ctx);

381

result = gpgme_op_decrypt_result(mc.ctx);

493

382

if(result == NULL){

494

383

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

495

384

} else {

496

if(result->unsupported_algorithm != NULL) {

497

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

498

result->unsupported_algorithm);

499

}

500

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

501

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

385

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

386

result->unsupported_algorithm);

387

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

388

result->wrong_key_usage);

502

389

if(result->file_name != NULL){

503

390

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

504

391

}

505

506

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

507

r = r->next){

392

gpgme_recipient_t recipient;

393

recipient = result->recipients;

394

while(recipient != NULL){

508

395

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

509

gpgme_pubkey_algo_name(r->pubkey_algo));

510

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

396

gpgme_pubkey_algo_name

397

(recipient->pubkey_algo));

398

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

511

399

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

512

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

400

recipient->status == GPG_ERR_NO_SECKEY

401

? "No" : "Yes");

402

recipient = recipient->next;

513

403

}

514

404

}

515

405

}

571

461

return plaintext_length;

572

462

}

573

463

574

__attribute__((warn_unused_result, const))

575

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

576

if(str == NULL)

577

return "(unknown)";

578

return str;

579

}

580

581

__attribute__((warn_unused_result))

582

static const char *safer_gnutls_strerror(int value){

583

const char *ret = gnutls_strerror(value);

584

return safe_string(ret);

464

static const char * safer_gnutls_strerror(int value){

465

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

466

-Wunreachable-code */

467

if(ret == NULL)

468

ret = "(unknown)";

469

return ret;

585

470

}

586

471

587

472

/* GnuTLS log function callback */

588

__attribute__((nonnull))

589

473

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

590

474

const char* string){

591

475

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

592

476

}

593

477

594

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

595

478

static int init_gnutls_global(const char *pubkeyfilename,

596

const char *seckeyfilename,

597

const char *dhparamsfilename,

598

mandos_context *mc){

479

const char *seckeyfilename){

599

480

int ret;

600

unsigned int uret;

601

481

602

482

if(debug){

603

483

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

604

484

}

605

485

486

ret = gnutls_global_init();

487

if(ret != GNUTLS_E_SUCCESS){

488

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

489

safer_gnutls_strerror(ret));

490

return -1;

491

}

492

606

493

if(debug){

607

494

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

608

495

* - GnuTLS manual

612

499

}

613

500

614

501

/* OpenPGP credentials */

615

ret = gnutls_certificate_allocate_credentials(&mc->cred);

502

ret = gnutls_certificate_allocate_credentials(&mc.cred);

616

503

if(ret != GNUTLS_E_SUCCESS){

617

504

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

618

505

safer_gnutls_strerror(ret));

506

gnutls_global_deinit();

619

507

return -1;

620

508

}

621

509

627

515

}

628

516

629

517

ret = gnutls_certificate_set_openpgp_key_file

630

(mc->cred, pubkeyfilename, seckeyfilename,

518

(mc.cred, pubkeyfilename, seckeyfilename,

631

519

GNUTLS_OPENPGP_FMT_BASE64);

632

520

if(ret != GNUTLS_E_SUCCESS){

633

521

fprintf_plus(stderr,

639

527

}

640

528

641

529

/* GnuTLS server initialization */

642

ret = gnutls_dh_params_init(&mc->dh_params);

530

ret = gnutls_dh_params_init(&mc.dh_params);

643

531

if(ret != GNUTLS_E_SUCCESS){

644

532

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

645

533

" initialization: %s\n",

646

534

safer_gnutls_strerror(ret));

647

535

goto globalfail;

648

536

}

649

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

650

if(dhparamsfilename != NULL){

651

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

652

do {

653

int dhpfile = open(dhparamsfilename, O_RDONLY);

654

if(dhpfile == -1){

655

perror_plus("open");

656

dhparamsfilename = NULL;

657

break;

658

}

659

size_t params_capacity = 0;

660

while(true){

661

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

662

(size_t)params.size,

663

(size_t)params_capacity);

664

if(params_capacity == 0){

665

perror_plus("incbuffer");

666

free(params.data);

667

params.data = NULL;

668

dhparamsfilename = NULL;

669

break;

670

}

671

ssize_t bytes_read = read(dhpfile,

672

params.data + params.size,

673

BUFFER_SIZE);

674

/* EOF */

675

if(bytes_read == 0){

676

break;

677

}

678

/* check bytes_read for failure */

679

if(bytes_read < 0){

680

perror_plus("read");

681

free(params.data);

682

params.data = NULL;

683

dhparamsfilename = NULL;

684

break;

685

}

686

params.size += (unsigned int)bytes_read;

687

}

688

ret = close(dhpfile);

689

if(ret == -1){

690

perror_plus("close");

691

}

692

if(params.data == NULL){

693

dhparamsfilename = NULL;

694

}

695

if(dhparamsfilename == NULL){

696

break;

697

}

698

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

699

GNUTLS_X509_FMT_PEM);

700

if(ret != GNUTLS_E_SUCCESS){

701

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

702

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

703

safer_gnutls_strerror(ret));

704

dhparamsfilename = NULL;

705

}

706

free(params.data);

707

} while(false);

708

}

709

if(dhparamsfilename == NULL){

710

if(mc->dh_bits == 0){

711

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

712

/* Try to read the private key file */

713

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

714

do {

715

int secfile = open(seckeyfilename, O_RDONLY);

716

if(secfile == -1){

717

perror_plus("open");

718

break;

719

}

720

size_t buffer_capacity = 0;

721

while(true){

722

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

723

(size_t)buffer.size,

724

(size_t)buffer_capacity);

725

if(buffer_capacity == 0){

726

perror_plus("incbuffer");

727

free(buffer.data);

728

buffer.data = NULL;

729

break;

730

}

731

ssize_t bytes_read = read(secfile,

732

buffer.data + buffer.size,

733

BUFFER_SIZE);

734

/* EOF */

735

if(bytes_read == 0){

736

break;

737

}

738

/* check bytes_read for failure */

739

if(bytes_read < 0){

740

perror_plus("read");

741

free(buffer.data);

742

buffer.data = NULL;

743

break;

744

}

745

buffer.size += (unsigned int)bytes_read;

746

}

747

close(secfile);

748

} while(false);

749

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

750

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

751

if(buffer.data != NULL){

752

{

753

gnutls_openpgp_privkey_t privkey = NULL;

754

ret = gnutls_openpgp_privkey_init(&privkey);

755

if(ret != GNUTLS_E_SUCCESS){

756

fprintf_plus(stderr, "Error initializing OpenPGP key"

757

" structure: %s",

758

safer_gnutls_strerror(ret));

759

free(buffer.data);

760

buffer.data = NULL;

761

} else {

762

ret = gnutls_openpgp_privkey_import

763

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

764

if(ret != GNUTLS_E_SUCCESS){

765

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

766

safer_gnutls_strerror(ret));

767

privkey = NULL;

768

}

769

free(buffer.data);

770

buffer.data = NULL;

771

if(privkey != NULL){

772

/* Use private key to suggest an appropriate

773

sec_param */

774

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

775

gnutls_openpgp_privkey_deinit(privkey);

776

if(debug){

777

fprintf_plus(stderr, "This OpenPGP key implies using"

778

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

779

safe_string(gnutls_sec_param_get_name

780

(sec_param)));

781

}

782

}

783

}

784

}

785

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

786

/* Err on the side of caution */

787

sec_param = GNUTLS_SEC_PARAM_ULTRA;

788

if(debug){

789

fprintf_plus(stderr, "Falling back to security parameter"

790

" \"%s\"\n",

791

safe_string(gnutls_sec_param_get_name

792

(sec_param)));

793

}

794

}

795

}

796

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

797

if(uret != 0){

798

mc->dh_bits = uret;

799

if(debug){

800

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

801

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

802

safe_string(gnutls_sec_param_get_name

803

(sec_param)),

804

mc->dh_bits);

805

}

806

} else {

807

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

808

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

809

safe_string(gnutls_sec_param_get_name

810

(sec_param)),

811

safer_gnutls_strerror(ret));

812

goto globalfail;

813

}

814

} else if(debug){

815

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

816

mc->dh_bits);

817

}

818

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

819

if(ret != GNUTLS_E_SUCCESS){

820

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

821

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

822

safer_gnutls_strerror(ret));

823

goto globalfail;

824

}

825

}

826

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

537

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

538

if(ret != GNUTLS_E_SUCCESS){

539

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

540

safer_gnutls_strerror(ret));

541

goto globalfail;

542

}

543

544

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

827

545

828

546

return 0;

829

547

830

548

globalfail:

831

549

832

gnutls_certificate_free_credentials(mc->cred);

833

gnutls_dh_params_deinit(mc->dh_params);

550

gnutls_certificate_free_credentials(mc.cred);

551

gnutls_global_deinit();

552

gnutls_dh_params_deinit(mc.dh_params);

834

553

return -1;

835

554

}

836

555

837

__attribute__((nonnull, warn_unused_result))

838

static int init_gnutls_session(gnutls_session_t *session,

839

mandos_context *mc){

556

static int init_gnutls_session(gnutls_session_t *session){

840

557

int ret;

841

558

/* GnuTLS session creation */

842

559

do {

854

571

{

855

572

const char *err;

856

573

do {

857

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

574

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

858

575

if(quit_now){

859

576

gnutls_deinit(*session);

860

577

return -1;

871

588

872

589

do {

873

590

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

874

mc->cred);

591

mc.cred);

875

592

if(quit_now){

876

593

gnutls_deinit(*session);

877

594

return -1;

887

604

/* ignore client certificate if any. */

888

605

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

889

606

607

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

608

890

609

return 0;

891

610

}

892

611

894

613

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

895

614

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

896

615

897

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

898

__attribute__((warn_unused_result))

899

int raise_privileges(void){

900

int old_errno = errno;

901

int ret = 0;

902

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

903

ret = errno;

904

}

905

errno = old_errno;

906

return ret;

907

}

908

909

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

910

__attribute__((warn_unused_result))

911

int raise_privileges_permanently(void){

912

int old_errno = errno;

913

int ret = raise_privileges();

914

if(ret != 0){

915

errno = old_errno;

916

return ret;

917

}

918

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

919

ret = errno;

920

}

921

errno = old_errno;

922

return ret;

923

}

924

925

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

926

__attribute__((warn_unused_result))

927

int lower_privileges(void){

928

int old_errno = errno;

929

int ret = 0;

930

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

931

ret = errno;

932

}

933

errno = old_errno;

934

return ret;

935

}

936

937

/* Lower privileges permanently */

938

__attribute__((warn_unused_result))

939

int lower_privileges_permanently(void){

940

int old_errno = errno;

941

int ret = 0;

942

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

943

ret = errno;

944

}

945

errno = old_errno;

946

return ret;

947

}

948

949

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

950

__attribute__((nonnull, warn_unused_result))

951

static bool add_delete_local_route(const bool add,

952

const char *address,

953

AvahiIfIndex if_index){

954

int ret;

955

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

956

char add_arg[] = "add";

957

char delete_arg[] = "delete";

958

char debug_flag[] = "--debug";

959

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

960

if(pluginhelperdir == NULL){

961

if(debug){

962

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

963

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

964

}

965

return false;

966

}

967

968

char interface[IF_NAMESIZE];

969

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

970

perror_plus("if_indextoname");

971

return false;

972

}

973

974

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

975

if(devnull == -1){

976

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

977

return false;

978

}

979

pid_t pid = fork();

980

if(pid == 0){

981

/* Child */

982

/* Raise privileges */

983

errno = raise_privileges_permanently();

984

if(errno != 0){

985

perror_plus("Failed to raise privileges");

986

/* _exit(EX_NOPERM); */

987

} else {

988

/* Set group */

989

errno = 0;

990

ret = setgid(0);

991

if(ret == -1){

992

perror_plus("setgid");

993

_exit(EX_NOPERM);

994

}

995

/* Reset supplementary groups */

996

errno = 0;

997

ret = setgroups(0, NULL);

998

if(ret == -1){

999

perror_plus("setgroups");

1000

_exit(EX_NOPERM);

1001

}

1002

}

1003

ret = dup2(devnull, STDIN_FILENO);

1004

if(ret == -1){

1005

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

1006

_exit(EX_OSERR);

1007

}

1008

ret = close(devnull);

1009

if(ret == -1){

1010

perror_plus("close");

1011

_exit(EX_OSERR);

1012

}

1013

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1014

if(ret == -1){

1015

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

1016

_exit(EX_OSERR);

1017

}

1018

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

1019

O_RDONLY

1020

| O_DIRECTORY

1021

| O_PATH

1022

| O_CLOEXEC));

1023

if(helperdir_fd == -1){

1024

perror_plus("open");

1025

_exit(EX_UNAVAILABLE);

1026

}

1027

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

1028

helper, O_RDONLY));

1029

if(helper_fd == -1){

1030

perror_plus("openat");

1031

close(helperdir_fd);

1032

_exit(EX_UNAVAILABLE);

1033

}

1034

close(helperdir_fd);

1035

#ifdef __GNUC__

1036

#pragma GCC diagnostic push

1037

#pragma GCC diagnostic ignored "-Wcast-qual"

1038

#endif

1039

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

1040

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

1041

interface, debug ? debug_flag : NULL, NULL },

1042

environ) == -1){

1043

#ifdef __GNUC__

1044

#pragma GCC diagnostic pop

1045

#endif

1046

perror_plus("fexecve");

1047

_exit(EXIT_FAILURE);

1048

}

1049

}

1050

if(pid == -1){

1051

perror_plus("fork");

1052

return false;

1053

}

1054

int status;

1055

pid_t pret = -1;

1056

errno = 0;

1057

do {

1058

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

1059

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

1060

int errno_raising = 0;

1061

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

1062

errno_raising = errno;

1063

perror_plus("Failed to raise privileges in order to"

1064

" kill helper program");

1065

}

1066

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

1067

perror_plus("kill");

1068

}

1069

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

1070

perror_plus("Failed to lower privileges after killing"

1071

" helper program");

1072

}

1073

return false;

1074

}

1075

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

1076

if(pret == -1){

1077

perror_plus("waitpid");

1078

return false;

1079

}

1080

if(WIFEXITED(status)){

1081

if(WEXITSTATUS(status) != 0){

1082

fprintf_plus(stderr, "Error: iprouteadddel exited"

1083

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

1084

return false;

1085

}

1086

return true;

1087

}

1088

if(WIFSIGNALED(status)){

1089

fprintf_plus(stderr, "Error: iprouteadddel died by"

1090

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

1091

return false;

1092

}

1093

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

1094

return false;

1095

}

1096

1097

__attribute__((nonnull, warn_unused_result))

1098

static bool add_local_route(const char *address,

1099

AvahiIfIndex if_index){

1100

if(debug){

1101

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

1102

}

1103

return add_delete_local_route(true, address, if_index);

1104

}

1105

1106

__attribute__((nonnull, warn_unused_result))

1107

static bool delete_local_route(const char *address,

1108

AvahiIfIndex if_index){

1109

if(debug){

1110

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

1111

}

1112

return add_delete_local_route(false, address, if_index);

1113

}

1114

1115

616

/* Called when a Mandos server is found */

1116

__attribute__((nonnull, warn_unused_result))

1117

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

617

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

1118

618

AvahiIfIndex if_index,

1119

int af, mandos_context *mc){

619

int af){

1120

620

int ret, tcp_sd = -1;

1121

621

ssize_t sret;

1122

struct sockaddr_storage to;

622

union {

623

struct sockaddr_in in;

624

struct sockaddr_in6 in6;

625

} to;

1123

626

char *buffer = NULL;

1124

627

char *decrypted_buffer = NULL;

1125

628

size_t buffer_length = 0;

1128

631

int retval = -1;

1129

632

gnutls_session_t session;

1130

633

int pf; /* Protocol family */

1131

bool route_added = false;

1132

634

1133

635

errno = 0;

1134

636

1150

652

return -1;

1151

653

}

1152

654

1153

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

1154

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

1155

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

1156

bool match = false;

1157

{

1158

char *interface = NULL;

1159

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

1160

mc->interfaces_size,

1161

interface))){

1162

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

1163

match = true;

1164

break;

1165

}

1166

}

1167

}

1168

if(not match){

1169

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

1170

connect to the server */

1171

if(debug){

1172

char interface[IF_NAMESIZE];

1173

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

1174

perror_plus("if_indextoname");

1175

} else {

1176

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

1177

" \"%s\"\n",

1178

if_indextoname((unsigned int)if_index,

1179

interface));

1180

}

1181

}

1182

return -1;

1183

}

1184

}

1185

1186

ret = init_gnutls_session(&session, mc);

655

ret = init_gnutls_session(&session);

1187

656

if(ret != 0){

1188

657

return -1;

1189

658

}

1190

659

1191

660

if(debug){

1192

661

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

1193

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

662

PRIu16 "\n", ip, port);

1194

663

}

1195

664

1196

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

665

tcp_sd = socket(pf, SOCK_STREAM, 0);

1197

666

if(tcp_sd < 0){

1198

667

int e = errno;

1199

668

perror_plus("socket");

1206

675

goto mandos_end;

1207

676

}

1208

677

678

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

1209

679

if(af == AF_INET6){

1210

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

1211

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

1212

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

680

to.in6.sin6_family = (sa_family_t)af;

681

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

1213

682

} else { /* IPv4 */

1214

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

1215

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

1216

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

683

to.in.sin_family = (sa_family_t)af;

684

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

1217

685

}

1218

686

if(ret < 0 ){

1219

687

int e = errno;

1228

696

goto mandos_end;

1229

697

}

1230

698

if(af == AF_INET6){

1231

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

1232

if(IN6_IS_ADDR_LINKLOCAL

1233

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

699

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

700

-Wconversion and

701

-Wunreachable-code */

702

703

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

704

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

705

-Wunreachable-code*/

1234

706

if(if_index == AVAHI_IF_UNSPEC){

1235

707

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

1236

708

" incomplete without a network interface\n");

1238

710

goto mandos_end;

1239

711

}

1240

712

/* Set the network interface number as scope */

1241

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

713

to.in6.sin6_scope_id = (uint32_t)if_index;

1242

714

}

1243

715

} else {

1244

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

716

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

717

-Wconversion and

718

-Wunreachable-code */

1245

719

}

1246

720

1247

721

if(quit_now){

1255

729

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

1256

730

perror_plus("if_indextoname");

1257

731

} else {

1258

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

1259

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

732

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

733

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

1260

734

}

1261

735

} else {

1262

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

1263

ip, (uintmax_t)port);

736

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

737

ip, port);

1264

738

}

1265

739

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

1266

740

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

1267

if(af == AF_INET6){

1268

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

1269

sizeof(struct sockaddr_in6),

1270

addrstr, sizeof(addrstr), NULL, 0,

1271

NI_NUMERICHOST);

1272

} else {

1273

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

1274

sizeof(struct sockaddr_in),

1275

addrstr, sizeof(addrstr), NULL, 0,

1276

NI_NUMERICHOST);

1277

}

1278

if(ret == EAI_SYSTEM){

1279

perror_plus("getnameinfo");

1280

} else if(ret != 0) {

1281

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

1282

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

1283

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

1284

}

1285

}

1286

1287

if(quit_now){

1288

errno = EINTR;

1289

goto mandos_end;

1290

}

1291

1292

while(true){

1293

if(af == AF_INET6){

1294

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

1295

sizeof(struct sockaddr_in6));

1296

} else {

1297

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

1298

sizeof(struct sockaddr_in));

1299

}

1300

if(ret < 0){

1301

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

1302

and if_index != AVAHI_IF_UNSPEC

1303

and connect_to == NULL

1304

and not route_added and

1305

((af == AF_INET6 and not

1306

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1307

&to)->sin6_addr)))

1308

or (af == AF_INET and

1309

/* Not a a IPv4LL address */

1310

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

1311

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

1312

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

1313

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

1314

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

1315

connect to a Mandos server announced by Avahi on a server

1316

host with a global address. Work around this by retrying

1317

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

1318

1319

Avahi bug reference:

1320

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

1321

https://bugs.debian.org/587961

1322

*/

1323

if(debug){

1324

fprintf_plus(stderr, "Mandos server unreachable, trying"

1325

" direct route\n");

1326

}

1327

int e = errno;

1328

route_added = add_local_route(ip, if_index);

1329

if(route_added){

1330

continue;

1331

}

1332

errno = e;

1333

}

1334

if(errno != ECONNREFUSED or debug){

1335

int e = errno;

1336

perror_plus("connect");

1337

errno = e;

1338

}

1339

goto mandos_end;

1340

}

1341

1342

if(quit_now){

1343

errno = EINTR;

1344

goto mandos_end;

1345

}

1346

break;

741

const char *pcret;

742

if(af == AF_INET6){

743

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

744

sizeof(addrstr));

745

} else {

746

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

747

sizeof(addrstr));

748

}

749

if(pcret == NULL){

750

perror_plus("inet_ntop");

751

} else {

752

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

753

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

754

}

755

}

756

}

757

758

if(quit_now){

759

errno = EINTR;

760

goto mandos_end;

761

}

762

763

if(af == AF_INET6){

764

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

765

} else {

766

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

767

}

768

if(ret < 0){

769

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

770

int e = errno;

771

perror_plus("connect");

772

errno = e;

773

}

774

goto mandos_end;

775

}

776

777

if(quit_now){

778

errno = EINTR;

779

goto mandos_end;

1347

780

}

1348

781

1349

782

const char *out = mandos_protocol_version;

1385

818

goto mandos_end;

1386

819

}

1387

820

1388

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

1389

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

1390

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

1391

gnutls_transport_set_ptr(session,

1392

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

821

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

822

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1393

823

1394

824

if(quit_now){

1395

825

errno = EINTR;

1500

930

if(buffer_length > 0){

1501

931

ssize_t decrypted_buffer_size;

1502

932

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1503

&decrypted_buffer, mc);

933

&decrypted_buffer);

1504

934

if(decrypted_buffer_size >= 0){

1505

935

1506

clearerr(stdout);

1507

936

written = 0;

1508

937

while(written < (size_t) decrypted_buffer_size){

1509

938

if(quit_now){

1525

954

}

1526

955

written += (size_t)ret;

1527

956

}

1528

ret = fflush(stdout);

1529

if(ret != 0){

1530

int e = errno;

1531

if(debug){

1532

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

1533

strerror(errno));

1534

}

1535

errno = e;

1536

goto mandos_end;

1537

}

1538

957

retval = 0;

1539

958

}

1540

959

}

1543

962

1544

963

mandos_end:

1545

964

{

1546

if(route_added){

1547

if(not delete_local_route(ip, if_index)){

1548

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

1549

" interface %d", ip, if_index);

1550

}

1551

}

1552

965

int e = errno;

1553

966

free(decrypted_buffer);

1554

967

free(buffer);

1555

968

if(tcp_sd >= 0){

1556

ret = close(tcp_sd);

969

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

1557

970

}

1558

971

if(ret == -1){

1559

972

if(e == 0){

1584

997

AVAHI_GCC_UNUSED AvahiStringList *txt,

1585

998

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1586

999

flags,

1587

void *mc){

1588

if(r == NULL){

1589

return;

1590

}

1000

AVAHI_GCC_UNUSED void* userdata){

1001

assert(r);

1591

1002

1592

1003

/* Called whenever a service has been resolved successfully or

1593

1004

timed out */

1594

1005

1595

1006

if(quit_now){

1596

avahi_s_service_resolver_free(r);

1597

1007

return;

1598

1008

}

1599

1009

1603

1013

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

1604

1014

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

1605

1015

domain,

1606

avahi_strerror(avahi_server_errno

1607

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

1016

avahi_strerror(avahi_server_errno(mc.server)));

1608

1017

break;

1609

1018

1610

1019

case AVAHI_RESOLVER_FOUND:

1616

1025

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

1617

1026

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

1618

1027

}

1619

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

1620

interface,

1621

avahi_proto_to_af(proto),

1622

mc);

1028

int ret = start_mandos_communication(ip, port, interface,

1029

avahi_proto_to_af(proto));

1623

1030

if(ret == 0){

1624

avahi_simple_poll_quit(simple_poll);

1031

avahi_simple_poll_quit(mc.simple_poll);

1625

1032

} else {

1626

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

1627

avahi_proto_to_af(proto),

1628

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

1629

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

1630

" list\n", name);

1631

}

1033

ret = add_server(ip, port, interface,

1034

avahi_proto_to_af(proto));

1632

1035

}

1633

1036

}

1634

1037

}

1644

1047

const char *domain,

1645

1048

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1646

1049

flags,

1647

void *mc){

1648

if(b == NULL){

1649

return;

1650

}

1050

AVAHI_GCC_UNUSED void* userdata){

1051

assert(b);

1651

1052

1652

1053

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

1653

1054

is removed from the LAN */

1661

1062

case AVAHI_BROWSER_FAILURE:

1662

1063

1663

1064

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

1664

avahi_strerror(avahi_server_errno

1665

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

1666

avahi_simple_poll_quit(simple_poll);

1065

avahi_strerror(avahi_server_errno(mc.server)));

1066

avahi_simple_poll_quit(mc.simple_poll);

1667

1067

return;

1668

1068

1669

1069

case AVAHI_BROWSER_NEW:

1672

1072

the callback function is called the Avahi server will free the

1673

1073

resolver for us. */

1674

1074

1675

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

1676

interface, protocol, name, type,

1677

domain, protocol, 0,

1678

resolve_callback, mc) == NULL)

1075

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

1076

name, type, domain, protocol, 0,

1077

resolve_callback, NULL) == NULL)

1679

1078

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

1680

1079

" %s\n", name,

1681

avahi_strerror(avahi_server_errno

1682

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

1080

avahi_strerror(avahi_server_errno(mc.server)));

1683

1081

break;

1684

1082

1685

1083

case AVAHI_BROWSER_REMOVE:

1704

1102

signal_received = sig;

1705

1103

int old_errno = errno;

1706

1104

/* set main loop to exit */

1707

if(simple_poll != NULL){

1708

avahi_simple_poll_quit(simple_poll);

1105

if(mc.simple_poll != NULL){

1106

avahi_simple_poll_quit(mc.simple_poll);

1709

1107

}

1710

1108

errno = old_errno;

1711

1109

}

1712

1110

1713

__attribute__((nonnull, warn_unused_result))

1714

1111

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

1715

1112

int ret;

1716

int old_errno;

1717

1113

1718

1114

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

1719

1115

if(s < 0){

1720

old_errno = errno;

1721

1116

perror_plus("socket");

1722

errno = old_errno;

1723

1117

return false;

1724

1118

}

1725

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

1726

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

1119

strcpy(ifr->ifr_name, ifname);

1727

1120

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1728

1121

if(ret == -1){

1729

1122

if(debug){

1730

old_errno = errno;

1731

1123

perror_plus("ioctl SIOCGIFFLAGS");

1732

errno = old_errno;

1733

}

1734

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

1735

old_errno = errno;

1736

perror_plus("close");

1737

errno = old_errno;

1738

1124

}

1739

1125

return false;

1740

1126

}

1741

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

1742

old_errno = errno;

1743

perror_plus("close");

1744

errno = old_errno;

1745

}

1746

1127

return true;

1747

1128

}

1748

1129

1749

__attribute__((nonnull, warn_unused_result))

1750

1130

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

1751

1131

1752

1132

/* Reject the loopback device */

1794

1174

* corresponds to an acceptable network device.

1795

1175

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

1796

1176

*/

1797

__attribute__((nonnull, warn_unused_result))

1798

1177

int good_interface(const struct dirent *if_entry){

1799

1178

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

1800

1179

return 0;

1816

1195

}

1817

1196

1818

1197

/*

1819

* This function determines if a network interface is up.

1820

*/

1821

__attribute__((nonnull, warn_unused_result))

1822

bool interface_is_up(const char *interface){

1823

struct ifreq ifr;

1824

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

1825

if(debug){

1826

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

1827

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

1828

}

1829

return false;

1830

}

1831

1832

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

1833

}

1834

1835

/*

1836

* This function determines if a network interface is running

1837

*/

1838

__attribute__((nonnull, warn_unused_result))

1839

bool interface_is_running(const char *interface){

1840

struct ifreq ifr;

1841

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

1842

if(debug){

1843

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

1844

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

1845

}

1846

return false;

1847

}

1848

1849

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

1850

}

1851

1852

__attribute__((nonnull, pure, warn_unused_result))

1198

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

1199

* corresponds to an acceptable network device which is up.

1200

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

1201

*/

1202

int up_interface(const struct dirent *if_entry){

1203

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

1204

return 0;

1205

}

1206

1207

struct ifreq ifr;

1208

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

1209

if(debug){

1210

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

1211

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

1212

}

1213

return 0;

1214

}

1215

1216

/* Reject down interfaces */

1217

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

1218

if(debug){

1219

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

1220

if_entry->d_name);

1221

}

1222

return 0;

1223

}

1224

1225

/* Reject non-running interfaces */

1226

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

1227

if(debug){

1228

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

1229

if_entry->d_name);

1230

}

1231

return 0;

1232

}

1233

1234

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

1235

return 0;

1236

}

1237

return 1;

1238

}

1239

1853

1240

int notdotentries(const struct dirent *direntry){

1854

1241

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

1855

1242

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

1862

1249

}

1863

1250

1864

1251

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

1865

__attribute__((nonnull, warn_unused_result))

1866

1252

int runnable_hook(const struct dirent *direntry){

1867

1253

int ret;

1868

1254

size_t sret;

1876

1262

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

1877

1263

"abcdefghijklmnopqrstuvwxyz"

1878

1264

"0123456789"

1879

"_.-");

1265

"_-");

1880

1266

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

1881

1267

/* Contains non-allowed characters */

1882

1268

if(debug){

1886

1272

return 0;

1887

1273

}

1888

1274

1889

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

1275

char *fullname = NULL;

1276

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

1277

if(ret < 0){

1278

perror_plus("asprintf");

1279

return 0;

1280

}

1281

1282

ret = stat(fullname, &st);

1890

1283

if(ret == -1){

1891

1284

if(debug){

1892

1285

perror_plus("Could not stat hook");

1916

1309

return 1;

1917

1310

}

1918

1311

1919

__attribute__((nonnull, warn_unused_result))

1920

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1921

mandos_context *mc){

1312

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1922

1313

int ret;

1923

1314

struct timespec now;

1924

1315

struct timespec waited_time;

1925

1316

intmax_t block_time;

1926

1317

1927

1318

while(true){

1928

if(mc->current_server == NULL){

1929

if(debug){

1319

if(mc.current_server == NULL){

1320

if (debug){

1930

1321

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

1931

1322

" No timeout!\n");

1932

1323

}

1933

1324

ret = avahi_simple_poll_iterate(s, -1);

1934

1325

} else {

1935

if(debug){

1326

if (debug){

1936

1327

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

1937

1328

" it, or wait\n");

1938

1329

}

1945

1336

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

1946

1337

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

1947

1338

waited_time.tv_sec = (now.tv_sec

1948

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

1339

- mc.current_server->last_seen.tv_sec);

1949

1340

waited_time.tv_nsec = (now.tv_nsec

1950

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

1341

- mc.current_server->last_seen.tv_nsec);

1951

1342

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

1952

1343

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

1953

1344

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

1955

1346

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

1956

1347

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

1957

1348

1958

if(debug){

1349

if (debug){

1959

1350

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

1960

1351

block_time);

1961

1352

}

1962

1353

1963

1354

if(block_time <= 0){

1964

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

1965

mc->current_server->port,

1966

mc->current_server->if_index,

1967

mc->current_server->af, mc);

1355

ret = start_mandos_communication(mc.current_server->ip,

1356

mc.current_server->port,

1357

mc.current_server->if_index,

1358

mc.current_server->af);

1968

1359

if(ret == 0){

1969

avahi_simple_poll_quit(s);

1360

avahi_simple_poll_quit(mc.simple_poll);

1970

1361

return 0;

1971

1362

}

1972

1363

ret = clock_gettime(CLOCK_MONOTONIC,

1973

&mc->current_server->last_seen);

1364

&mc.current_server->last_seen);

1974

1365

if(ret == -1){

1975

1366

perror_plus("clock_gettime");

1976

1367

return -1;

1977

1368

}

1978

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

1369

mc.current_server = mc.current_server->next;

1979

1370

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

1980

1371

servers, but don't block */

1981

1372

}

1983

1374

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

1984

1375

}

1985

1376

if(ret != 0){

1986

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

1377

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

1987

1378

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

1988

1379

}

1989

1380

}

1990

1381

}

1991

1382

}

1992

1383

1993

__attribute__((nonnull))

1994

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

1384

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

1995

1385

const float delay){

1996

struct dirent **direntries = NULL;

1997

if(hookdir_fd == -1){

1998

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1999

| O_CLOEXEC);

2000

if(hookdir_fd == -1){

2001

if(errno == ENOENT){

2002

if(debug){

2003

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

2004

" found\n", hookdir);

2005

}

2006

} else {

2007

perror_plus("open");

2008

}

2009

return;

2010

}

2011

}

2012

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

2013

if(devnull == -1){

2014

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

2015

return;

2016

}

2017

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

2018

runnable_hook, alphasort);

1386

struct dirent **direntries;

1387

struct dirent *direntry;

1388

int ret;

1389

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

1390

alphasort);

2019

1391

if(numhooks == -1){

2020

1392

perror_plus("scandir");

2021

close(devnull);

2022

return;

2023

}

2024

struct dirent *direntry;

2025

int ret;

2026

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

2027

direntry = direntries[i];

2028

if(debug){

2029

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

2030

direntry->d_name);

2031

}

2032

pid_t hook_pid = fork();

2033

if(hook_pid == 0){

2034

/* Child */

2035

/* Raise privileges */

2036

errno = raise_privileges_permanently();

2037

if(errno != 0){

2038

perror_plus("Failed to raise privileges");

2039

_exit(EX_NOPERM);

2040

}

2041

/* Set group */

2042

errno = 0;

2043

ret = setgid(0);

2044

if(ret == -1){

2045

perror_plus("setgid");

2046

_exit(EX_NOPERM);

2047

}

2048

/* Reset supplementary groups */

2049

errno = 0;

2050

ret = setgroups(0, NULL);

2051

if(ret == -1){

2052

perror_plus("setgroups");

2053

_exit(EX_NOPERM);

2054

}

2055

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

2056

if(ret == -1){

2057

perror_plus("setenv");

2058

_exit(EX_OSERR);

2059

}

2060

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

2061

if(ret == -1){

2062

perror_plus("setenv");

2063

_exit(EX_OSERR);

2064

}

2065

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

2066

if(ret == -1){

2067

perror_plus("setenv");

2068

_exit(EX_OSERR);

2069

}

2070

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

2071

if(ret == -1){

2072

perror_plus("setenv");

2073

_exit(EX_OSERR);

2074

}

2075

char *delaystring;

2076

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

2077

if(ret == -1){

1393

} else {

1394

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

1395

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

1396

direntry = direntries[i];

1397

char *fullname = NULL;

1398

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

1399

if(ret < 0){

2078

1400

perror_plus("asprintf");

2079

_exit(EX_OSERR);

2080

}

2081

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

2082

if(ret == -1){

1401

continue;

1402

}

1403

if(debug){

1404

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

1405

direntry->d_name);

1406

}

1407

pid_t hook_pid = fork();

1408

if(hook_pid == 0){

1409

/* Child */

1410

/* Raise privileges */

1411

errno = 0;

1412

ret = seteuid(0);

1413

if(ret == -1){

1414

perror_plus("seteuid");

1415

}

1416

/* Raise privileges even more */

1417

errno = 0;

1418

ret = setuid(0);

1419

if(ret == -1){

1420

perror_plus("setuid");

1421

}

1422

/* Set group */

1423

errno = 0;

1424

ret = setgid(0);

1425

if(ret == -1){

1426

perror_plus("setgid");

1427

}

1428

/* Reset supplementary groups */

1429

errno = 0;

1430

ret = setgroups(0, NULL);

1431

if(ret == -1){

1432

perror_plus("setgroups");

1433

}

1434

fprintf_plus(stderr, "Child: getuid() = %d\n", getuid());

1435

fprintf_plus(stderr, "Child: geteuid() = %d\n", geteuid());

1436

dup2(devnull, STDIN_FILENO);

1437

close(devnull);

1438

dup2(STDERR_FILENO, STDOUT_FILENO);

1439

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

1440

if(ret == -1){

1441

perror_plus("setenv");

1442

_exit(EX_OSERR);

1443

}

1444

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

1445

if(ret == -1){

1446

perror_plus("setenv");

1447

_exit(EX_OSERR);

1448

}

1449

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

1450

if(ret == -1){

1451

perror_plus("setenv");

1452

_exit(EX_OSERR);

1453

}

1454

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

1455

if(ret == -1){

1456

perror_plus("setenv");

1457

_exit(EX_OSERR);

1458

}

1459

char *delaystring;

1460

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

1461

if(ret == -1){

1462

perror_plus("asprintf");

1463

_exit(EX_OSERR);

1464

}

1465

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

1466

if(ret == -1){

1467

free(delaystring);

1468

perror_plus("setenv");

1469

_exit(EX_OSERR);

1470

}

2083

1471

free(delaystring);

2084

perror_plus("setenv");

2085

_exit(EX_OSERR);

2086

}

2087

free(delaystring);

2088

if(connect_to != NULL){

2089

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

2090

if(ret == -1){

2091

perror_plus("setenv");

2092

_exit(EX_OSERR);

2093

}

2094

}

2095

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

2096

direntry->d_name,

2097

O_RDONLY));

2098

if(hook_fd == -1){

2099

perror_plus("openat");

2100

_exit(EXIT_FAILURE);

2101

}

2102

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

2103

perror_plus("close");

2104

_exit(EXIT_FAILURE);

2105

}

2106

ret = dup2(devnull, STDIN_FILENO);

2107

if(ret == -1){

2108

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

2109

_exit(EX_OSERR);

2110

}

2111

ret = close(devnull);

2112

if(ret == -1){

2113

perror_plus("close");

2114

_exit(EX_OSERR);

2115

}

2116

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2117

if(ret == -1){

2118

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

2119

_exit(EX_OSERR);

2120

}

2121

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

2122

environ) == -1){

2123

perror_plus("fexecve");

2124

_exit(EXIT_FAILURE);

2125

}

2126

} else {

2127

if(hook_pid == -1){

2128

perror_plus("fork");

2129

free(direntry);

2130

continue;

2131

}

2132

int status;

2133

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

2134

perror_plus("waitpid");

2135

free(direntry);

2136

continue;

2137

}

2138

if(WIFEXITED(status)){

2139

if(WEXITSTATUS(status) != 0){

2140

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

2141

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

2142

WEXITSTATUS(status));

2143

free(direntry);

2144

continue;

2145

}

2146

} else if(WIFSIGNALED(status)){

2147

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

2148

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

2149

WTERMSIG(status));

2150

free(direntry);

2151

continue;

2152

} else {

2153

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

2154

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

2155

free(direntry);

2156

continue;

2157

}

2158

}

2159

if(debug){

2160

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

2161

direntry->d_name);

2162

}

2163

free(direntry);

2164

}

2165

free(direntries);

2166

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

2167

perror_plus("close");

2168

} else {

2169

hookdir_fd = -1;

2170

}

2171

close(devnull);

2172

}

2173

2174

__attribute__((nonnull, warn_unused_result))

2175

int bring_up_interface(const char *const interface,

2176

const float delay){

2177

int old_errno = errno;

2178

int ret;

2179

struct ifreq network;

2180

unsigned int if_index = if_nametoindex(interface);

2181

if(if_index == 0){

2182

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

2183

errno = old_errno;

2184

return ENXIO;

2185

}

2186

2187

if(quit_now){

2188

errno = old_errno;

2189

return EINTR;

2190

}

2191

2192

if(not interface_is_up(interface)){

2193

int ret_errno = 0;

2194

int ioctl_errno = 0;

2195

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

2196

ret_errno = errno;

2197

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

2198

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

2199

errno = old_errno;

2200

return ret_errno;

2201

}

2202

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

2203

2204

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

2205

if(sd == -1){

2206

ret_errno = errno;

2207

perror_plus("socket");

2208

errno = old_errno;

2209

return ret_errno;

2210

}

2211

2212

if(quit_now){

2213

ret = close(sd);

2214

if(ret == -1){

2215

perror_plus("close");

2216

}

2217

errno = old_errno;

2218

return EINTR;

2219

}

2220

2221

if(debug){

2222

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

2223

interface);

2224

}

2225

2226

/* Raise privileges */

2227

ret_errno = raise_privileges();

2228

if(ret_errno != 0){

2229

errno = ret_errno;

2230

perror_plus("Failed to raise privileges");

2231

}

2232

2233

#ifdef __linux__

2234

int ret_linux;

2235

bool restore_loglevel = false;

2236

if(ret_errno == 0){

2237

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2238

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

2239

ret_linux = klogctl(8, NULL, 5);

2240

if(ret_linux == -1){

2241

perror_plus("klogctl");

2242

} else {

2243

restore_loglevel = true;

2244

}

2245

}

2246

#endif /* __linux__ */

2247

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

2248

ioctl_errno = errno;

2249

#ifdef __linux__

2250

if(restore_loglevel){

2251

ret_linux = klogctl(7, NULL, 0);

2252

if(ret_linux == -1){

2253

perror_plus("klogctl");

2254

}

2255

}

2256

#endif /* __linux__ */

2257

2258

/* If raise_privileges() succeeded above */

2259

if(ret_errno == 0){

2260

/* Lower privileges */

2261

ret_errno = lower_privileges();

2262

if(ret_errno != 0){

2263

errno = ret_errno;

2264

perror_plus("Failed to lower privileges");

2265

}

2266

}

2267

2268

/* Close the socket */

2269

ret = close(sd);

2270

if(ret == -1){

2271

perror_plus("close");

2272

}

2273

2274

if(ret_setflags == -1){

2275

errno = ioctl_errno;

2276

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2277

errno = old_errno;

2278

return ioctl_errno;

2279

}

2280

} else if(debug){

2281

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

2282

interface);

2283

}

2284

2285

/* Sleep checking until interface is running.

2286

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

2287

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

2288

if(interface_is_running(interface)){

2289

break;

2290

}

2291

struct timespec sleeptime = { .tv_nsec = 250000000 };

2292

ret = nanosleep(&sleeptime, NULL);

2293

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

2294

perror_plus("nanosleep");

2295

}

2296

}

2297

2298

errno = old_errno;

2299

return 0;

2300

}

2301

2302

__attribute__((nonnull, warn_unused_result))

2303

int take_down_interface(const char *const interface){

2304

int old_errno = errno;

2305

struct ifreq network;

2306

unsigned int if_index = if_nametoindex(interface);

2307

if(if_index == 0){

2308

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

2309

errno = old_errno;

2310

return ENXIO;

2311

}

2312

if(interface_is_up(interface)){

2313

int ret_errno = 0;

2314

int ioctl_errno = 0;

2315

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

2316

ret_errno = errno;

2317

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

2318

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

2319

errno = old_errno;

2320

return ret_errno;

2321

}

2322

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

2323

2324

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

2325

if(sd == -1){

2326

ret_errno = errno;

2327

perror_plus("socket");

2328

errno = old_errno;

2329

return ret_errno;

2330

}

2331

2332

if(debug){

2333

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

2334

interface);

2335

}

2336

2337

/* Raise privileges */

2338

ret_errno = raise_privileges();

2339

if(ret_errno != 0){

2340

errno = ret_errno;

2341

perror_plus("Failed to raise privileges");

2342

}

2343

2344

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

2345

ioctl_errno = errno;

2346

2347

/* If raise_privileges() succeeded above */

2348

if(ret_errno == 0){

2349

/* Lower privileges */

2350

ret_errno = lower_privileges();

2351

if(ret_errno != 0){

2352

errno = ret_errno;

2353

perror_plus("Failed to lower privileges");

2354

}

2355

}

2356

2357

/* Close the socket */

2358

int ret = close(sd);

2359

if(ret == -1){

2360

perror_plus("close");

2361

}

2362

2363

if(ret_setflags == -1){

2364

errno = ioctl_errno;

2365

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2366

errno = old_errno;

2367

return ioctl_errno;

2368

}

2369

} else if(debug){

2370

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

2371

interface);

2372

}

2373

2374

errno = old_errno;

2375

return 0;

1472

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

1473

perror_plus("execl");

1474

} else {

1475

int status;

1476

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

1477

perror_plus("waitpid");

1478

free(fullname);

1479

continue;

1480

}

1481

if(WIFEXITED(status)){

1482

if(WEXITSTATUS(status) != 0){

1483

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

1484

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

1485

WEXITSTATUS(status));

1486

free(fullname);

1487

continue;

1488

}

1489

} else if(WIFSIGNALED(status)){

1490

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

1491

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

1492

WTERMSIG(status));

1493

free(fullname);

1494

continue;

1495

} else {

1496

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

1497

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

1498

free(fullname);

1499

continue;

1500

}

1501

}

1502

free(fullname);

1503

if(debug){

1504

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

1505

direntry->d_name);

1506

}

1507

}

1508

close(devnull);

1509

}

1510

return true;

2376

1511

}

2377

1512

2378

1513

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

2379

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

2380

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

2381

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

2382

.current_server = NULL, .interfaces = NULL,

2383

.interfaces_size = 0 };

2384

1514

AvahiSServiceBrowser *sb = NULL;

2385

error_t ret_errno;

1515

int error;

2386

1516

int ret;

2387

1517

intmax_t tmpmax;

2388

1518

char *tmp;

2389

1519

int exitcode = EXIT_SUCCESS;

2390

char *interfaces_to_take_down = NULL;

2391

size_t interfaces_to_take_down_size = 0;

2392

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

2393

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

2394

char *tempdir = NULL;

1520

const char *interface = "";

1521

struct ifreq network;

1522

int sd = -1;

1523

bool take_down_interface = false;

1524

uid_t uid;

1525

gid_t gid;

1526

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

1527

bool tempdir_created = false;

2395

1528

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2396

1529

const char *seckey = PATHDIR "/" SECKEY;

2397

1530

const char *pubkey = PATHDIR "/" PUBKEY;

2398

const char *dh_params_file = NULL;

2399

char *interfaces_hooks = NULL;

2400

1531

2401

1532

bool gnutls_initialized = false;

2402

1533

bool gpgme_initialized = false;

2454

1585

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

2455

1586

" Diffie-Hellman key exchange",

2456

1587

.group = 2 },

2457

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

2458

.arg = "FILE",

2459

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

2460

" for the Diffie-Hellman key exchange",

2461

.group = 2 },

2462

1588

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

2463

1589

.arg = "STRING",

2464

1590

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

2469

1595

.group = 2 },

2470

1596

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

2471

1597

.arg = "SECONDS",

2472

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

1598

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

2473

1599

.group = 2 },

2474

1600

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

2475

1601

.arg = "DIR",

2498

1624

connect_to = arg;

2499

1625

break;

2500

1626

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

2501

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

2502

arg, (int)',');

2503

if(ret_errno != 0){

2504

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

2505

}

1627

interface = arg;

2506

1628

break;

2507

1629

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

2508

1630

seckey = arg;

2519

1641

}

2520

1642

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

2521

1643

break;

2522

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

2523

dh_params_file = arg;

2524

break;

2525

1644

case 130: /* --priority */

2526

1645

mc.priority = arg;

2527

1646

break;

2554

1673

argp_state_help(state, state->out_stream,

2555

1674

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2556

1675

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

1676

fprintf_plus(state->out_stream,

1677

"Mandos plugin mandos-client: ");

2557

1678

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

2558

1679

exit(argp_err_exit_status);

2559

1680

break;

2567

1688

.args_doc = "",

2568

1689

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

2569

1690

" passwords from a Mandos server" };

2570

ret_errno = argp_parse(&argp, argc, argv,

2571

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2572

switch(ret_errno){

1691

ret = argp_parse(&argp, argc, argv,

1692

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1693

switch(ret){

2573

1694

case 0:

2574

1695

break;

2575

1696

case ENOMEM:

2576

1697

default:

2577

errno = ret_errno;

1698

errno = ret;

2578

1699

perror_plus("argp_parse");

2579

1700

exitcode = EX_OSERR;

2580

1701

goto end;

2583

1704

goto end;

2584

1705

}

2585

1706

}

2586

1707

2587

1708

{

2588

1709

/* Work around Debian bug #633582:

2589

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

1710

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

2590

1711

2591

/* Re-raise privileges */

2592

ret = raise_privileges();

2593

if(ret != 0){

2594

errno = ret;

2595

perror_plus("Failed to raise privileges");

1712

/* Re-raise priviliges */

1713

errno = 0;

1714

ret = seteuid(0);

1715

if(ret == -1){

1716

perror_plus("seteuid");

2596

1717

} else {

2597

1718

struct stat st;

2598

1719

2613

1734

}

2614

1735

}

2615

1736

}

2616

close(seckey_fd);

1737

TEMP_FAILURE_RETRY(close(seckey_fd));

2617

1738

}

2618

1739

}

2619

1740

2620

1741

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

2621

1742

int pubkey_fd = open(pubkey, O_RDONLY);

2622

1743

if(pubkey_fd == -1){

2634

1755

}

2635

1756

}

2636

1757

}

2637

close(pubkey_fd);

2638

}

2639

}

2640

2641

if(dh_params_file != NULL

2642

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

2643

int dhparams_fd = open(dh_params_file, O_RDONLY);

2644

if(dhparams_fd == -1){

2645

perror_plus("open");

2646

} else {

2647

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

2648

if(ret == -1){

2649

perror_plus("fstat");

2650

} else {

2651

if(S_ISREG(st.st_mode)

2652

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

2653

ret = fchown(dhparams_fd, uid, gid);

2654

if(ret == -1){

2655

perror_plus("fchown");

2656

}

2657

}

2658

}

2659

close(dhparams_fd);

2660

}

2661

}

2662

1758

TEMP_FAILURE_RETRY(close(pubkey_fd));

1759

}

1760

}

1761

2663

1762

/* Lower privileges */

2664

ret = lower_privileges();

2665

if(ret != 0){

2666

errno = ret;

2667

perror_plus("Failed to lower privileges");

2668

}

2669

}

2670

}

2671

2672

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

2673

{

2674

char *interface = NULL;

2675

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

2676

interface))){

2677

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

2678

and if_nametoindex(interface) == 0){

2679

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

2680

fprintf_plus(stderr, "Not using nonexisting interface"

2681

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

2682

}

2683

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

2684

interface = NULL;

1763

errno = 0;

1764

ret = seteuid(uid);

1765

if(ret == -1){

1766

perror_plus("seteuid");

2685

1767

}

2686

1768

}

2687

1769

}

2688

1770

2689

1771

/* Run network hooks */

2690

{

2691

if(mc.interfaces != NULL){

2692

interfaces_hooks = malloc(mc.interfaces_size);

2693

if(interfaces_hooks == NULL){

2694

perror_plus("malloc");

2695

goto end;

2696

}

2697

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

2698

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

2699

}

2700

run_network_hooks("start", interfaces_hooks != NULL ?

2701

interfaces_hooks : "", delay);

1772

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

1773

goto end;

2702

1774

}

2703

1775

2704

1776

if(not debug){

2705

1777

avahi_set_log_function(empty_log);

2706

1778

}

2707

1779

1780

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

1781

struct dirent **direntries;

1782

/* First look for interfaces that are up */

1783

ret = scandir(sys_class_net, &direntries, up_interface,

1784

alphasort);

1785

if(ret == 0){

1786

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

1787

free(direntries);

1788

ret = scandir(sys_class_net, &direntries, good_interface,

1789

alphasort);

1790

}

1791

if(ret >= 1){

1792

/* Pick the first interface returned */

1793

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

1794

if(debug){

1795

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

1796

}

1797

if(interface == NULL){

1798

perror_plus("malloc");

1799

free(direntries);

1800

exitcode = EXIT_FAILURE;

1801

goto end;

1802

}

1803

free(direntries);

1804

} else {

1805

free(direntries);

1806

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

1807

exitcode = EXIT_FAILURE;

1808

goto end;

1809

}

1810

}

1811

2708

1812

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

2709

1813

from the signal handler */

2710

1814

/* Initialize the pseudo-RNG for Avahi */

2711

1815

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

2712

simple_poll = avahi_simple_poll_new();

2713

if(simple_poll == NULL){

1816

mc.simple_poll = avahi_simple_poll_new();

1817

if(mc.simple_poll == NULL){

2714

1818

fprintf_plus(stderr,

2715

1819

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

2716

1820

exitcode = EX_UNAVAILABLE;

2780

1884

}

2781

1885

}

2782

1886

2783

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

2784

if(mc.interfaces == NULL){

2785

struct dirent **direntries = NULL;

2786

/* Look for any good interfaces */

2787

ret = scandir(sys_class_net, &direntries, good_interface,

2788

alphasort);

2789

if(ret >= 1){

2790

/* Add all found interfaces to interfaces list */

2791

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

2792

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

2793

direntries[i]->d_name);

2794

if(ret_errno != 0){

2795

errno = ret_errno;

2796

perror_plus("argz_add");

2797

free(direntries[i]);

2798

continue;

2799

}

2800

if(debug){

2801

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

2802

direntries[i]->d_name);

2803

}

2804

free(direntries[i]);

2805

}

2806

free(direntries);

2807

} else {

2808

if(ret == 0){

2809

free(direntries);

2810

}

2811

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

2812

exitcode = EXIT_FAILURE;

2813

goto end;

2814

}

2815

}

2816

2817

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

2818

{

2819

char *interface = NULL;

2820

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

2821

interface))){

2822

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

2823

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

2824

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

2825

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

2826

interface);

2827

interface = NULL;

2828

while((interface = argz_next(mc.interfaces,

2829

mc.interfaces_size, interface))){

2830

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

2831

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

2832

interface);

2833

interface = NULL;

1887

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

1888

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

1889

if_index = (AvahiIfIndex) if_nametoindex(interface);

1890

if(if_index == 0){

1891

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

1892

exitcode = EX_UNAVAILABLE;

1893

goto end;

1894

}

1895

1896

if(quit_now){

1897

goto end;

1898

}

1899

1900

/* Re-raise priviliges */

1901

errno = 0;

1902

ret = seteuid(0);

1903

if(ret == -1){

1904

perror_plus("seteuid");

1905

}

1906

1907

#ifdef __linux__

1908

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1909

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

1910

ret = klogctl(8, NULL, 5);

1911

bool restore_loglevel = true;

1912

if(ret == -1){

1913

restore_loglevel = false;

1914

perror_plus("klogctl");

1915

}

1916

#endif /* __linux__ */

1917

1918

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1919

if(sd < 0){

1920

perror_plus("socket");

1921

exitcode = EX_OSERR;

1922

#ifdef __linux__

1923

if(restore_loglevel){

1924

ret = klogctl(7, NULL, 0);

1925

if(ret == -1){

1926

perror_plus("klogctl");

1927

}

1928

}

1929

#endif /* __linux__ */

1930

/* Lower privileges */

1931

errno = 0;

1932

ret = seteuid(uid);

1933

if(ret == -1){

1934

perror_plus("seteuid");

1935

}

1936

goto end;

1937

}

1938

strcpy(network.ifr_name, interface);

1939

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

1940

if(ret == -1){

1941

perror_plus("ioctl SIOCGIFFLAGS");

1942

#ifdef __linux__

1943

if(restore_loglevel){

1944

ret = klogctl(7, NULL, 0);

1945

if(ret == -1){

1946

perror_plus("klogctl");

1947

}

1948

}

1949

#endif /* __linux__ */

1950

exitcode = EX_OSERR;

1951

/* Lower privileges */

1952

errno = 0;

1953

ret = seteuid(uid);

1954

if(ret == -1){

1955

perror_plus("seteuid");

1956

}

1957

goto end;

1958

}

1959

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

1960

network.ifr_flags |= IFF_UP;

1961

take_down_interface = true;

1962

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

1963

if(ret == -1){

1964

take_down_interface = false;

1965

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1966

exitcode = EX_OSERR;

1967

#ifdef __linux__

1968

if(restore_loglevel){

1969

ret = klogctl(7, NULL, 0);

1970

if(ret == -1){

1971

perror_plus("klogctl");

2834

1972

}

2835

1973

}

1974

#endif /* __linux__ */

1975

/* Lower privileges */

1976

errno = 0;

1977

ret = seteuid(uid);

1978

if(ret == -1){

1979

perror_plus("seteuid");

1980

}

1981

goto end;

1982

}

1983

}

1984

/* Sleep checking until interface is running.

1985

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

1986

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

1987

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

1988

if(ret == -1){

1989

perror_plus("ioctl SIOCGIFFLAGS");

1990

} else if(network.ifr_flags & IFF_RUNNING){

2836

1991

break;

2837

1992

}

2838

bool interface_was_up = interface_is_up(interface);

2839

errno = bring_up_interface(interface, delay);

2840

if(not interface_was_up){

2841

if(errno != 0){

2842

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

2843

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

2844

} else {

2845

errno = argz_add(&interfaces_to_take_down,

2846

&interfaces_to_take_down_size,

2847

interface);

2848

if(errno != 0){

2849

perror_plus("argz_add");

2850

}

2851

}

2852

}

2853

}

2854

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

2855

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

2856

}

2857

}

2858

2859

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

2860

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

2861

if(debug){

2862

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

2863

mc.interfaces);

2864

}

2865

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

1993

struct timespec sleeptime = { .tv_nsec = 250000000 };

1994

ret = nanosleep(&sleeptime, NULL);

1995

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

1996

perror_plus("nanosleep");

1997

}

1998

}

1999

if(not take_down_interface){

2000

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

2001

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

2002

if(ret == -1){

2003

perror_plus("close");

2004

}

2005

}

2006

#ifdef __linux__

2007

if(restore_loglevel){

2008

/* Restores kernel loglevel to default */

2009

ret = klogctl(7, NULL, 0);

2010

if(ret == -1){

2011

perror_plus("klogctl");

2012

}

2013

}

2014

#endif /* __linux__ */

2015

/* Lower privileges */

2016

errno = 0;

2017

/* Lower privileges */

2018

ret = seteuid(uid);

2019

if(ret == -1){

2020

perror_plus("seteuid");

2021

}

2866

2022

}

2867

2023

2868

2024

if(quit_now){

2869

2025

goto end;

2870

2026

}

2871

2027

2872

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

2028

ret = init_gnutls_global(pubkey, seckey);

2873

2029

if(ret == -1){

2874

2030

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

2875

2031

exitcode = EX_UNAVAILABLE;

2882

2038

goto end;

2883

2039

}

2884

2040

2885

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

2886

tempdir = mkdtemp(run_tempdir);

2887

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

2888

if(debug){

2889

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

2890

run_tempdir, old_tempdir);

2891

}

2892

tempdir = mkdtemp(old_tempdir);

2893

}

2894

if(tempdir == NULL){

2041

if(mkdtemp(tempdir) == NULL){

2895

2042

perror_plus("mkdtemp");

2896

2043

goto end;

2897

2044

}

2045

tempdir_created = true;

2898

2046

2899

2047

if(quit_now){

2900

2048

goto end;

2901

2049

}

2902

2050

2903

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

2051

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

2904

2052

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

2905

2053

exitcode = EX_UNAVAILABLE;

2906

2054

goto end;

2916

2064

/* Connect directly, do not use Zeroconf */

2917

2065

/* (Mainly meant for debugging) */

2918

2066

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

2919

2920

2067

if(address == NULL){

2921

2068

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

2922

2069

exitcode = EX_USAGE;

2927

2074

goto end;

2928

2075

}

2929

2076

2930

in_port_t port;

2077

uint16_t port;

2931

2078

errno = 0;

2932

2079

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

2933

2080

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

2934

or tmpmax != (in_port_t)tmpmax){

2081

or tmpmax != (uint16_t)tmpmax){

2935

2082

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

2936

2083

exitcode = EX_USAGE;

2937

2084

goto end;

2938

2085

}

2939

2086

2940

2087

if(quit_now){

2941

2088

goto end;

2942

2089

}

2943

2090

2944

port = (in_port_t)tmpmax;

2091

port = (uint16_t)tmpmax;

2945

2092

*address = '\0';

2946

2093

/* Colon in address indicates IPv6 */

2947

2094

int af;

2963

2110

}

2964

2111

2965

2112

while(not quit_now){

2966

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

2967

&mc);

2113

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

2968

2114

if(quit_now or ret == 0){

2969

2115

break;

2970

2116

}

2972

2118

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

2973

2119

(int)retry_interval);

2974

2120

}

2975

sleep((unsigned int)retry_interval);

2121

sleep((int)retry_interval);

2976

2122

}

2977

2123

2978

if(not quit_now){

2124

if (not quit_now){

2979

2125

exitcode = EXIT_SUCCESS;

2980

2126

}

2981

2127

2996

2142

config.publish_domain = 0;

2997

2143

2998

2144

/* Allocate a new server */

2999

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

3000

&config, NULL, NULL, &ret);

2145

mc.server = avahi_server_new(avahi_simple_poll_get

2146

(mc.simple_poll), &config, NULL,

2147

NULL, &error);

3001

2148

3002

2149

/* Free the Avahi configuration data */

3003

2150

avahi_server_config_free(&config);

3006

2153

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

3007

2154

if(mc.server == NULL){

3008

2155

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

3009

avahi_strerror(ret));

2156

avahi_strerror(error));

3010

2157

exitcode = EX_UNAVAILABLE;

3011

2158

goto end;

3012

2159

}

3018

2165

/* Create the Avahi service browser */

3019

2166

sb = avahi_s_service_browser_new(mc.server, if_index,

3020

2167

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

3021

NULL, 0, browse_callback,

3022

(void *)&mc);

2168

NULL, 0, browse_callback, NULL);

3023

2169

if(sb == NULL){

3024

2170

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

3025

2171

avahi_strerror(avahi_server_errno(mc.server)));

3036

2182

if(debug){

3037

2183

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

3038

2184

}

3039

3040

ret = avahi_loop_with_timeout(simple_poll,

3041

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

2185

2186

ret = avahi_loop_with_timeout(mc.simple_poll,

2187

(int)(retry_interval * 1000));

3042

2188

if(debug){

3043

2189

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

3044

2190

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

3047

2193

end:

3048

2194

3049

2195

if(debug){

3050

if(signal_received){

3051

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

3052

argv[0], signal_received,

3053

strsignal(signal_received));

3054

} else {

3055

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

3056

}

2196

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

3057

2197

}

3058

2198

3059

2199

/* Cleanup things */

3060

free(mc.interfaces);

3061

3062

2200

if(sb != NULL)

3063

2201

avahi_s_service_browser_free(sb);

3064

2202

3065

2203

if(mc.server != NULL)

3066

2204

avahi_server_free(mc.server);

3067

2205

3068

if(simple_poll != NULL)

3069

avahi_simple_poll_free(simple_poll);

2206

if(mc.simple_poll != NULL)

2207

avahi_simple_poll_free(mc.simple_poll);

3070

2208

3071

2209

if(gnutls_initialized){

3072

2210

gnutls_certificate_free_credentials(mc.cred);

2211

gnutls_global_deinit();

3073

2212

gnutls_dh_params_deinit(mc.dh_params);

3074

2213

}

3075

2214

3083

2222

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

3084

2223

while(mc.current_server != NULL){

3085

2224

server *next = mc.current_server->next;

3086

#ifdef __GNUC__

3087

#pragma GCC diagnostic push

3088

#pragma GCC diagnostic ignored "-Wcast-qual"

3089

#endif

3090

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

3091

#ifdef __GNUC__

3092

#pragma GCC diagnostic pop

3093

#endif

3094

2225

free(mc.current_server);

3095

2226

mc.current_server = next;

3096

2227

}

3097

2228

}

3098

2229

3099

/* Re-raise privileges */

2230

/* Run network hooks */

2231

run_network_hooks("stop", interface, delay);

2232

2233

/* Re-raise priviliges */

3100

2234

{

3101

ret = raise_privileges();

3102

if(ret != 0){

3103

errno = ret;

3104

perror_plus("Failed to raise privileges");

3105

} else {

3106

3107

/* Run network hooks */

3108

run_network_hooks("stop", interfaces_hooks != NULL ?

3109

interfaces_hooks : "", delay);

3110

3111

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

3112

{

3113

char *interface = NULL;

3114

while((interface = argz_next(interfaces_to_take_down,

3115

interfaces_to_take_down_size,

3116

interface))){

3117

ret = take_down_interface(interface);

3118

if(ret != 0){

3119

errno = ret;

3120

perror_plus("Failed to take down interface");

3121

}

3122

}

3123

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

3124

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

3125

" down\n");

3126

}

3127

}

2235

errno = 0;

2236

ret = seteuid(0);

2237

if(ret == -1){

2238

perror_plus("seteuid");

3128

2239

}

3129

2240

3130

ret = lower_privileges_permanently();

3131

if(ret != 0){

3132

errno = ret;

3133

perror_plus("Failed to lower privileges permanently");

2241

/* Take down the network interface */

2242

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

2243

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

2244

if(ret == -1){

2245

perror_plus("ioctl SIOCGIFFLAGS");

2246

} else if(network.ifr_flags & IFF_UP){

2247

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

2248

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

2249

if(ret == -1){

2250

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2251

}

2252

}

2253

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

2254

if(ret == -1){

2255

perror_plus("close");

2256

}

3134

2257

}

3135

2258

}

3136

3137

free(interfaces_to_take_down);

3138

free(interfaces_hooks);

3139

3140

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

3141

uintmax_t level){

2259

/* Lower privileges permanently */

2260

errno = 0;

2261

ret = setuid(uid);

2262

if(ret == -1){

2263

perror_plus("setuid");

2264

}

2265

2266

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

2267

if(tempdir_created){

3142

2268

struct dirent **direntries = NULL;

3143

int dret;

3144

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

3145

O_RDONLY

3146

| O_NOFOLLOW

3147

| O_DIRECTORY

3148

| O_PATH));

3149

if(dir_fd == -1){

3150

perror_plus("open");

3151

return;

3152

}

3153

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

3154

notdotentries, alphasort);

3155

if(numentries >= 0){

2269

struct dirent *direntry = NULL;

2270

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

2271

alphasort);

2272

if (numentries > 0){

3156

2273

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

3157

if(debug){

3158

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

3159

dirname, direntries[i]->d_name);

3160

}

3161

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

3162

if(dret == -1){

3163

if(errno == EISDIR){

3164

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

3165

AT_REMOVEDIR);

3166

}

3167

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

3168

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

3169

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

3170

/* Recurse only in this special case */

3171

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

3172

dret = 0;

3173

}

3174

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

3175

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

3176

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

3177

}

3178

}

3179

free(direntries[i]);

3180

}

3181

3182

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

3183

free(direntries);

3184

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3185

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

3186

perror_plus("rmdir");

3187

}

3188

} else {

3189

perror_plus("scandirat");

3190

}

3191

close(dir_fd);

3192

}

3193

3194

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

3195

if(tempdir != NULL){

3196

clean_dir_at(-1, tempdir, 0);

2274

direntry = direntries[i];

2275

char *fullname = NULL;

2276

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

2277

direntry->d_name);

2278

if(ret < 0){

2279

perror_plus("asprintf");

2280

continue;

2281

}

2282

ret = remove(fullname);

2283

if(ret == -1){

2284

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

2285

strerror(errno));

2286

}

2287

free(fullname);

2288

}

2289

}

2290

2291

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

2292

free(direntries);

2293

if (numentries == -1){

2294

perror_plus("scandir");

2295

}

2296

ret = rmdir(tempdir);

2297

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

2298

perror_plus("rmdir");

2299

}

3197

2300

}

3198

2301

3199

2302

if(quit_now){