/mandos/trunk : revision 304

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

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*

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* Everything else is

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*

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

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

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

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*/

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

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#ifndef _LARGEFILE_SOURCE

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#define _LARGEFILE_SOURCE

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#endif

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#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

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#endif

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

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

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stdout, ferror(), remove() */

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stdout, ferror(), sscanf(),

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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 <stdlib.h> /* free(), EXIT_SUCCESS, EXIT_FAILURE,

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srand() */

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

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

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

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sockaddr_in6, PF_INET6,

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SOCK_STREAM, uid_t, gid_t, open(),

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opendir(), DIR */

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

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

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

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inet_pton(), connect() */

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

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

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*/

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

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strtoimax() */

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

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

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

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

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SIOCSIFFLAGS, if_indextoname(),

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if_nametoindex(), IF_NAMESIZE */

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INET_ADDRSTRLEN, INET6_ADDRSTRLEN

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*/

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

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

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

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

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getuid(), getgid(), setuid(),

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setgid() */

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

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

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

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argp_state, struct argp,

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argp_parse(), ARGP_KEY_ARG,

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ARGP_KEY_END, ARGP_ERR_UNKNOWN */

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

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sigaction(), SIGTERM, sig_atomic_t,

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raise() */

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

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EX_NOHOST, EX_IOERR, EX_PROTOCOL */

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

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WEXITSTATUS(), WTERMSIG() */

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

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#ifdef __linux__

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

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#endif /* __linux__ */

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#endif

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/* Avahi */

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/* All Avahi types, constants and functions

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init_gnutls_session(),

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GNUTLS_* */

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#include <gnutls/openpgp.h>

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/* gnutls_certificate_set_openpgp_key_file(),

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GNUTLS_OPENPGP_FMT_BASE64 */

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/* gnutls_certificate_set_openpgp_key_file(),

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GNUTLS_OPENPGP_FMT_BASE64 */

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/* GPGME */

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#include <gpgme.h> /* All GPGME types, constants and

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

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#define SECKEY "seckey.txt"

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#define PUBKEY "pubkey.txt"

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

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bool debug = false;

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static const char mandos_protocol_version[] = "1";

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

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

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

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char *connect_to = NULL;

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const char *hookdir = HOOKDIR;

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/* 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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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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struct server *next;

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struct server *prev;

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} server;

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

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

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typedef struct {

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127

gnutls_dh_params_t dh_params;

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const char *priority;

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gpgme_ctx_t ctx;

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server *current_server;

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} mandos_context;

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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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168

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

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program_invocation_short_name);

175

perror(print_text);

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}

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

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

180

va_list ap;

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va_start (ap, format);

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

184

program_invocation_short_name));

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

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}

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188

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/*

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

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

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* Make room in "buffer" for at least BUFFER_SIZE additional bytes.

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* "buffer_capacity" is how much is currently allocated,

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* "buffer_length" is how much is already used.

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136

*/

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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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size_t adjustbuffer(char **buffer, size_t buffer_length,

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size_t buffer_capacity){

195

139

if(buffer_length + BUFFER_SIZE > buffer_capacity){

196

140

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

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141

if(buffer == NULL){

202

146

return buffer_capacity;

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}

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

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

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int af){

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int ret;

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

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if(new_server == NULL){

211

perror_plus("malloc");

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return false;

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}

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

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.port = port,

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.if_index = if_index,

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.af = af };

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if(new_server->ip == NULL){

219

perror_plus("strdup");

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return false;

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}

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/* Special case of first server */

223

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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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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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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mc.current_server->prev = new_server;

233

}

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

235

if(ret == -1){

236

perror_plus("clock_gettime");

237

return false;

238

}

239

return true;

240

}

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242

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/*

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150

* Initialize GPGME.

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151

*/

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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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static bool init_gpgme(mandos_context *mc, const char *seckey,

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const char *pubkey, const char *tempdir){

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int ret;

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gpgme_error_t rc;

248

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gpgme_engine_info_t engine_info;

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252

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

253

161

*/

254

162

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;

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

260

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if(fd == -1){

261

perror_plus("open");

168

perror("open");

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return false;

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170

}

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rc = gpgme_data_new_from_fd(&pgp_data, fd);

266

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if(rc != GPG_ERR_NO_ERROR){

267

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

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}

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rc = gpgme_op_import(mc.ctx, pgp_data);

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

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}

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

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if(ret == -1){

281

perror_plus("close");

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perror("close");

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}

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gpgme_data_release(pgp_data);

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return true;

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}

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if(debug){

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

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fprintf(stderr, "Initialize gpgme\n");

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}

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/* Init GPGME */

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gpgme_check_version(NULL);

293

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rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

294

201

if(rc != GPG_ERR_NO_ERROR){

295

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

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}

299

206

300

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

207

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

301

208

rc = gpgme_get_engine_info(&engine_info);

302

209

if(rc != GPG_ERR_NO_ERROR){

303

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

304

gpgme_strsource(rc), gpgme_strerror(rc));

210

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

211

gpgme_strsource(rc), gpgme_strerror(rc));

305

212

return false;

306

213

}

307

214

while(engine_info != NULL){

313

220

engine_info = engine_info->next;

314

221

}

315

222

if(engine_info == NULL){

316

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

317

tempdir);

223

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

318

224

return false;

319

225

}

320

226

321

227

/* Create new GPGME "context" */

322

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

228

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

323

229

if(rc != GPG_ERR_NO_ERROR){

324

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

325

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

326

gpgme_strerror(rc));

230

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

231

gpgme_strsource(rc), gpgme_strerror(rc));

327

232

return false;

328

233

}

329

234

331

236

return false;

332

237

}

333

238

334

return true;

239

return true;

335

240

}

336

241

337

242

/*

338

243

* Decrypt OpenPGP data.

339

244

* Returns -1 on error

340

245

*/

341

static ssize_t pgp_packet_decrypt(const char *cryptotext,

246

static ssize_t pgp_packet_decrypt(const mandos_context *mc,

247

const char *cryptotext,

342

248

size_t crypto_size,

343

249

char **plaintext){

344

250

gpgme_data_t dh_crypto, dh_plain;

348

254

ssize_t plaintext_length = 0;

349

255

350

256

if(debug){

351

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

257

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

352

258

}

353

259

354

260

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

355

261

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

356

262

0);

357

263

if(rc != GPG_ERR_NO_ERROR){

358

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

359

gpgme_strsource(rc), gpgme_strerror(rc));

264

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

265

gpgme_strsource(rc), gpgme_strerror(rc));

360

266

return -1;

361

267

}

362

268

363

269

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

364

270

rc = gpgme_data_new(&dh_plain);

365

271

if(rc != GPG_ERR_NO_ERROR){

366

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

367

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

368

gpgme_strsource(rc), gpgme_strerror(rc));

272

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

273

gpgme_strsource(rc), gpgme_strerror(rc));

369

274

gpgme_data_release(dh_crypto);

370

275

return -1;

371

276

}

372

277

373

278

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

374

279

data buffer */

375

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

280

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

376

281

if(rc != GPG_ERR_NO_ERROR){

377

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

378

gpgme_strsource(rc), gpgme_strerror(rc));

282

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

283

gpgme_strsource(rc), gpgme_strerror(rc));

379

284

plaintext_length = -1;

380

285

if(debug){

381

286

gpgme_decrypt_result_t result;

382

result = gpgme_op_decrypt_result(mc.ctx);

287

result = gpgme_op_decrypt_result(mc->ctx);

383

288

if(result == NULL){

384

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

289

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

385

290

} else {

386

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

387

result->unsupported_algorithm);

388

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

389

result->wrong_key_usage);

291

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

292

result->unsupported_algorithm);

293

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

294

result->wrong_key_usage);

390

295

if(result->file_name != NULL){

391

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

296

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

392

297

}

393

298

gpgme_recipient_t recipient;

394

299

recipient = result->recipients;

395

while(recipient != NULL){

396

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

397

gpgme_pubkey_algo_name

398

(recipient->pubkey_algo));

399

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

400

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

401

recipient->status == GPG_ERR_NO_SECKEY

402

? "No" : "Yes");

403

recipient = recipient->next;

300

if(recipient){

301

while(recipient != NULL){

302

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

303

gpgme_pubkey_algo_name(recipient->pubkey_algo));

304

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

305

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

306

recipient->status == GPG_ERR_NO_SECKEY

307

? "No" : "Yes");

308

recipient = recipient->next;

309

}

404

310

}

405

311

}

406

312

}

408

314

}

409

315

410

316

if(debug){

411

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

317

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

412

318

}

413

319

414

320

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

415

321

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

416

perror_plus("gpgme_data_seek");

322

perror("gpgme_data_seek");

417

323

plaintext_length = -1;

418

324

goto decrypt_end;

419

325

}

420

326

421

327

*plaintext = NULL;

422

328

while(true){

423

plaintext_capacity = incbuffer(plaintext,

424

(size_t)plaintext_length,

425

plaintext_capacity);

329

plaintext_capacity = adjustbuffer(plaintext,

330

(size_t)plaintext_length,

331

plaintext_capacity);

426

332

if(plaintext_capacity == 0){

427

perror_plus("incbuffer");

428

plaintext_length = -1;

429

goto decrypt_end;

333

perror("adjustbuffer");

334

plaintext_length = -1;

335

goto decrypt_end;

430

336

}

431

337

432

338

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

437

343

break;

438

344

}

439

345

if(ret < 0){

440

perror_plus("gpgme_data_read");

346

perror("gpgme_data_read");

441

347

plaintext_length = -1;

442

348

goto decrypt_end;

443

349

}

445

351

}

446

352

447

353

if(debug){

448

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

354

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

449

355

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

450

356

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

451

357

}

473

379

/* GnuTLS log function callback */

474

380

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

475

381

const char* string){

476

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

382

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

477

383

}

478

384

479

static int init_gnutls_global(const char *pubkeyfilename,

385

static int init_gnutls_global(mandos_context *mc,

386

const char *pubkeyfilename,

480

387

const char *seckeyfilename){

481

388

int ret;

482

389

483

390

if(debug){

484

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

391

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

485

392

}

486

393

487

394

ret = gnutls_global_init();

488

395

if(ret != GNUTLS_E_SUCCESS){

489

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

490

safer_gnutls_strerror(ret));

396

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

397

safer_gnutls_strerror(ret));

491

398

return -1;

492

399

}

493

400

500

407

}

501

408

502

409

/* OpenPGP credentials */

503

ret = gnutls_certificate_allocate_credentials(&mc.cred);

410

gnutls_certificate_allocate_credentials(&mc->cred);

504

411

if(ret != GNUTLS_E_SUCCESS){

505

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

506

safer_gnutls_strerror(ret));

412

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

413

from

414

-Wunreachable-code

415

*/

416

safer_gnutls_strerror(ret));

507

417

gnutls_global_deinit();

508

418

return -1;

509

419

}

510

420

511

421

if(debug){

512

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

513

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

514

pubkeyfilename,

515

seckeyfilename);

422

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

423

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

424

seckeyfilename);

516

425

}

517

426

518

427

ret = gnutls_certificate_set_openpgp_key_file

519

(mc.cred, pubkeyfilename, seckeyfilename,

428

(mc->cred, pubkeyfilename, seckeyfilename,

520

429

GNUTLS_OPENPGP_FMT_BASE64);

521

430

if(ret != GNUTLS_E_SUCCESS){

522

fprintf_plus(stderr,

523

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

524

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

525

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

526

safer_gnutls_strerror(ret));

431

fprintf(stderr,

432

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

433

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

434

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

435

safer_gnutls_strerror(ret));

527

436

goto globalfail;

528

437

}

529

438

530

439

/* GnuTLS server initialization */

531

ret = gnutls_dh_params_init(&mc.dh_params);

440

ret = gnutls_dh_params_init(&mc->dh_params);

532

441

if(ret != GNUTLS_E_SUCCESS){

533

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

534

" initialization: %s\n",

535

safer_gnutls_strerror(ret));

442

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

443

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

536

444

goto globalfail;

537

445

}

538

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

446

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

539

447

if(ret != GNUTLS_E_SUCCESS){

540

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

541

safer_gnutls_strerror(ret));

448

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

449

safer_gnutls_strerror(ret));

542

450

goto globalfail;

543

451

}

544

452

545

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

453

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

546

454

547

455

return 0;

548

456

549

457

globalfail:

550

458

551

gnutls_certificate_free_credentials(mc.cred);

459

gnutls_certificate_free_credentials(mc->cred);

552

460

gnutls_global_deinit();

553

gnutls_dh_params_deinit(mc.dh_params);

461

gnutls_dh_params_deinit(mc->dh_params);

554

462

return -1;

555

463

}

556

464

557

static int init_gnutls_session(gnutls_session_t *session){

465

static int init_gnutls_session(mandos_context *mc,

466

gnutls_session_t *session){

558

467

int ret;

559

468

/* GnuTLS session creation */

560

do {

561

ret = gnutls_init(session, GNUTLS_SERVER);

562

if(quit_now){

563

return -1;

564

}

565

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

469

ret = gnutls_init(session, GNUTLS_SERVER);

566

470

if(ret != GNUTLS_E_SUCCESS){

567

fprintf_plus(stderr,

568

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

569

safer_gnutls_strerror(ret));

471

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

472

safer_gnutls_strerror(ret));

570

473

}

571

474

572

475

{

573

476

const char *err;

574

do {

575

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

576

if(quit_now){

577

gnutls_deinit(*session);

578

return -1;

579

}

580

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

477

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

581

478

if(ret != GNUTLS_E_SUCCESS){

582

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

583

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

584

safer_gnutls_strerror(ret));

479

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

480

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

481

safer_gnutls_strerror(ret));

585

482

gnutls_deinit(*session);

586

483

return -1;

587

484

}

588

485

}

589

486

590

do {

591

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

592

mc.cred);

593

if(quit_now){

594

gnutls_deinit(*session);

595

return -1;

596

}

597

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

487

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

488

mc->cred);

598

489

if(ret != GNUTLS_E_SUCCESS){

599

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

600

safer_gnutls_strerror(ret));

490

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

491

safer_gnutls_strerror(ret));

601

492

gnutls_deinit(*session);

602

493

return -1;

603

494

}

604

495

605

496

/* ignore client certificate if any. */

606

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

497

gnutls_certificate_server_set_request(*session,

498

GNUTLS_CERT_IGNORE);

607

499

608

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

500

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

609

501

610

502

return 0;

611

503

}

617

509

/* Called when a Mandos server is found */

618

510

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

619

511

AvahiIfIndex if_index,

620

int af){

621

int ret, tcp_sd = -1;

512

mandos_context *mc, int af){

513

int ret, tcp_sd;

622

514

ssize_t sret;

623

515

union {

624

516

struct sockaddr_in in;

625

517

struct sockaddr_in6 in6;

626

518

} to;

627

519

char *buffer = NULL;

628

char *decrypted_buffer = NULL;

520

char *decrypted_buffer;

629

521

size_t buffer_length = 0;

630

522

size_t buffer_capacity = 0;

523

ssize_t decrypted_buffer_size;

631

524

size_t written;

632

int retval = -1;

525

int retval = 0;

633

526

gnutls_session_t session;

634

527

int pf; /* Protocol family */

635

528

636

errno = 0;

637

638

if(quit_now){

639

errno = EINTR;

640

return -1;

641

}

642

643

529

switch(af){

644

530

case AF_INET6:

645

531

pf = PF_INET6;

648

534

pf = PF_INET;

649

535

break;

650

536

default:

651

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

652

errno = EINVAL;

537

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

653

538

return -1;

654

539

}

655

540

656

ret = init_gnutls_session(&session);

541

ret = init_gnutls_session(mc, &session);

657

542

if(ret != 0){

658

543

return -1;

659

544

}

660

545

661

546

if(debug){

662

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

663

PRIu16 "\n", ip, port);

547

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

548

"\n", ip, port);

664

549

}

665

550

666

551

tcp_sd = socket(pf, SOCK_STREAM, 0);

667

552

if(tcp_sd < 0){

668

int e = errno;

669

perror_plus("socket");

670

errno = e;

671

goto mandos_end;

672

}

673

674

if(quit_now){

675

errno = EINTR;

676

goto mandos_end;

553

perror("socket");

554

return -1;

677

555

}

678

556

679

557

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

680

558

if(af == AF_INET6){

681

to.in6.sin6_family = (sa_family_t)af;

559

to.in6.sin6_family = (uint16_t)af;

682

560

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

683

561

} else { /* IPv4 */

684

562

to.in.sin_family = (sa_family_t)af;

685

563

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

686

564

}

687

565

if(ret < 0 ){

688

int e = errno;

689

perror_plus("inet_pton");

690

errno = e;

691

goto mandos_end;

566

perror("inet_pton");

567

return -1;

692

568

}

693

569

if(ret == 0){

694

int e = errno;

695

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

696

errno = e;

697

goto mandos_end;

570

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

571

return -1;

698

572

}

699

573

if(af == AF_INET6){

700

574

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

703

577

704

578

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

705

579

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

706

-Wunreachable-code*/

580

-Wunreachable-code*/

707

581

if(if_index == AVAHI_IF_UNSPEC){

708

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

709

" incomplete without a network interface\n");

710

errno = EINVAL;

711

goto mandos_end;

582

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

583

" without a network interface\n");

584

return -1;

712

585

}

713

586

/* Set the network interface number as scope */

714

587

to.in6.sin6_scope_id = (uint32_t)if_index;

719

592

-Wunreachable-code */

720

593

}

721

594

722

if(quit_now){

723

errno = EINTR;

724

goto mandos_end;

725

}

726

727

595

if(debug){

728

596

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

729

597

char interface[IF_NAMESIZE];

730

598

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

731

perror_plus("if_indextoname");

599

perror("if_indextoname");

732

600

} else {

733

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

734

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

601

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

602

ip, interface, port);

735

603

}

736

604

} else {

737

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

738

ip, port);

605

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

606

port);

739

607

}

740

608

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

741

609

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

748

616

sizeof(addrstr));

749

617

}

750

618

if(pcret == NULL){

751

perror_plus("inet_ntop");

619

perror("inet_ntop");

752

620

} else {

753

621

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

754

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

622

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

755

623

}

756

624

}

757

625

}

758

626

759

if(quit_now){

760

errno = EINTR;

761

goto mandos_end;

762

}

763

764

627

if(af == AF_INET6){

765

628

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

766

629

} else {

767

630

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

768

631

}

769

632

if(ret < 0){

770

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

771

int e = errno;

772

perror_plus("connect");

773

errno = e;

774

}

775

goto mandos_end;

776

}

777

778

if(quit_now){

779

errno = EINTR;

780

goto mandos_end;

633

perror("connect");

634

return -1;

781

635

}

782

636

783

637

const char *out = mandos_protocol_version;

785

639

while(true){

786

640

size_t out_size = strlen(out);

787

641

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

788

out_size - written));

642

out_size - written));

789

643

if(ret == -1){

790

int e = errno;

791

perror_plus("write");

792

errno = e;

644

perror("write");

645

retval = -1;

793

646

goto mandos_end;

794

647

}

795

648

written += (size_t)ret;

803

656

break;

804

657

}

805

658

}

806

807

if(quit_now){

808

errno = EINTR;

809

goto mandos_end;

810

}

811

659

}

812

660

813

661

if(debug){

814

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

815

}

816

817

if(quit_now){

818

errno = EINTR;

819

goto mandos_end;

820

}

821

822

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

662

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

663

}

664

823

665

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

824

666

825

if(quit_now){

826

errno = EINTR;

827

goto mandos_end;

828

}

829

830

do {

667

do{

831

668

ret = gnutls_handshake(session);

832

if(quit_now){

833

errno = EINTR;

834

goto mandos_end;

835

}

836

669

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

837

670

838

671

if(ret != GNUTLS_E_SUCCESS){

839

672

if(debug){

840

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

673

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

841

674

gnutls_perror(ret);

842

675

}

843

errno = EPROTO;

676

retval = -1;

844

677

goto mandos_end;

845

678

}

846

679

847

680

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

848

681

849

682

if(debug){

850

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

851

" %s\n", ip);

683

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

684

ip);

852

685

}

853

686

854

687

while(true){

855

856

if(quit_now){

857

errno = EINTR;

858

goto mandos_end;

859

}

860

861

buffer_capacity = incbuffer(&buffer, buffer_length,

862

buffer_capacity);

688

buffer_capacity = adjustbuffer(&buffer, buffer_length,

689

buffer_capacity);

863

690

if(buffer_capacity == 0){

864

int e = errno;

865

perror_plus("incbuffer");

866

errno = e;

867

goto mandos_end;

868

}

869

870

if(quit_now){

871

errno = EINTR;

691

perror("adjustbuffer");

692

retval = -1;

872

693

goto mandos_end;

873

694

}

874

695

883

704

case GNUTLS_E_AGAIN:

884

705

break;

885

706

case GNUTLS_E_REHANDSHAKE:

886

do {

707

do{

887

708

ret = gnutls_handshake(session);

888

889

if(quit_now){

890

errno = EINTR;

891

goto mandos_end;

892

}

893

709

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

894

710

if(ret < 0){

895

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

896

"***\n");

711

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

897

712

gnutls_perror(ret);

898

errno = EPROTO;

713

retval = -1;

899

714

goto mandos_end;

900

715

}

901

716

break;

902

717

default:

903

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

904

" encrypted session with Mandos server\n");

718

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

719

" encrypted session with Mandos server\n");

720

retval = -1;

905

721

gnutls_bye(session, GNUTLS_SHUT_RDWR);

906

errno = EIO;

907

722

goto mandos_end;

908

723

}

909

724

} else {

912

727

}

913

728

914

729

if(debug){

915

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

916

}

917

918

if(quit_now){

919

errno = EINTR;

920

goto mandos_end;

921

}

922

923

do {

924

ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);

925

if(quit_now){

926

errno = EINTR;

927

goto mandos_end;

928

}

929

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

730

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

731

}

732

733

gnutls_bye(session, GNUTLS_SHUT_RDWR);

930

734

931

735

if(buffer_length > 0){

932

ssize_t decrypted_buffer_size;

933

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

736

decrypted_buffer_size = pgp_packet_decrypt(mc, buffer,

737

buffer_length,

934

738

&decrypted_buffer);

935

739

if(decrypted_buffer_size >= 0){

936

937

740

written = 0;

938

741

while(written < (size_t) decrypted_buffer_size){

939

if(quit_now){

940

errno = EINTR;

941

goto mandos_end;

942

}

943

944

742

ret = (int)fwrite(decrypted_buffer + written, 1,

945

743

(size_t)decrypted_buffer_size - written,

946

744

stdout);

947

745

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

948

int e = errno;

949

746

if(debug){

950

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

951

strerror(errno));

747

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

748

strerror(errno));

952

749

}

953

errno = e;

954

goto mandos_end;

750

retval = -1;

751

break;

955

752

}

956

753

written += (size_t)ret;

957

754

}

958

retval = 0;

755

free(decrypted_buffer);

756

} else {

757

retval = -1;

959

758

}

759

} else {

760

retval = -1;

960

761

}

961

762

962

763

/* Shutdown procedure */

963

764

964

765

mandos_end:

965

{

966

int e = errno;

967

free(decrypted_buffer);

968

free(buffer);

969

if(tcp_sd >= 0){

970

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

971

}

972

if(ret == -1){

973

if(e == 0){

974

e = errno;

975

}

976

perror_plus("close");

977

}

978

gnutls_deinit(session);

979

errno = e;

980

if(quit_now){

981

errno = EINTR;

982

retval = -1;

983

}

766

free(buffer);

767

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

768

if(ret == -1){

769

perror("close");

984

770

}

771

gnutls_deinit(session);

985

772

return retval;

986

773

}

987

774

998

785

AVAHI_GCC_UNUSED AvahiStringList *txt,

999

786

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1000

787

flags,

1001

AVAHI_GCC_UNUSED void* userdata){

788

void* userdata){

789

mandos_context *mc = userdata;

1002

790

assert(r);

1003

791

1004

792

/* Called whenever a service has been resolved successfully or

1005

793

timed out */

1006

794

1007

if(quit_now){

1008

return;

1009

}

1010

1011

795

switch(event){

1012

796

default:

1013

797

case AVAHI_RESOLVER_FAILURE:

1014

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

1015

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

1016

domain,

1017

avahi_strerror(avahi_server_errno(mc.server)));

798

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

799

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

800

avahi_strerror(avahi_server_errno(mc->server)));

1018

801

break;

1019

802

1020

803

case AVAHI_RESOLVER_FOUND:

1022

805

char ip[AVAHI_ADDRESS_STR_MAX];

1023

806

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

1024

807

if(debug){

1025

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

1026

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

1027

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

808

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

809

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

810

ip, (intmax_t)interface, port);

1028

811

}

1029

int ret = start_mandos_communication(ip, port, interface,

812

int ret = start_mandos_communication(ip, port, interface, mc,

1030

813

avahi_proto_to_af(proto));

1031

814

if(ret == 0){

1032

avahi_simple_poll_quit(mc.simple_poll);

1033

} else {

1034

if(not add_server(ip, port, interface,

1035

avahi_proto_to_af(proto))){

1036

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

1037

" list\n", name);

1038

}

815

avahi_simple_poll_quit(mc->simple_poll);

1039

816

}

1040

817

}

1041

818

}

1051

828

const char *domain,

1052

829

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1053

830

flags,

1054

AVAHI_GCC_UNUSED void* userdata){

831

void* userdata){

832

mandos_context *mc = userdata;

1055

833

assert(b);

1056

834

1057

835

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

1058

836

is removed from the LAN */

1059

837

1060

if(quit_now){

1061

return;

1062

}

1063

1064

838

switch(event){

1065

839

default:

1066

840

case AVAHI_BROWSER_FAILURE:

1067

841

1068

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

1069

avahi_strerror(avahi_server_errno(mc.server)));

1070

avahi_simple_poll_quit(mc.simple_poll);

842

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

843

avahi_strerror(avahi_server_errno(mc->server)));

844

avahi_simple_poll_quit(mc->simple_poll);

1071

845

return;

1072

846

1073

847

case AVAHI_BROWSER_NEW:

1076

850

the callback function is called the Avahi server will free the

1077

851

resolver for us. */

1078

852

1079

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

1080

name, type, domain, protocol, 0,

1081

resolve_callback, NULL) == NULL)

1082

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

1083

" %s\n", name,

1084

avahi_strerror(avahi_server_errno(mc.server)));

853

if(!(avahi_s_service_resolver_new(mc->server, interface,

854

protocol, name, type, domain,

855

AVAHI_PROTO_INET6, 0,

856

resolve_callback, mc)))

857

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

858

name, avahi_strerror(avahi_server_errno(mc->server)));

1085

859

break;

1086

860

1087

861

case AVAHI_BROWSER_REMOVE:

1090

864

case AVAHI_BROWSER_ALL_FOR_NOW:

1091

865

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1092

866

if(debug){

1093

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

1094

" searching...\n");

867

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

1095

868

}

1096

869

break;

1097

870

}

1098

871

}

1099

872

1100

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

1101

static void handle_sigterm(int sig){

1102

if(quit_now){

1103

return;

1104

}

1105

quit_now = 1;

1106

signal_received = sig;

1107

int old_errno = errno;

1108

/* set main loop to exit */

1109

if(mc.simple_poll != NULL){

1110

avahi_simple_poll_quit(mc.simple_poll);

1111

}

1112

errno = old_errno;

1113

}

1114

1115

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

1116

int ret;

1117

1118

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

1119

if(s < 0){

1120

perror_plus("socket");

1121

return false;

1122

}

1123

strcpy(ifr->ifr_name, ifname);

1124

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1125

if(ret == -1){

1126

if(debug){

1127

perror_plus("ioctl SIOCGIFFLAGS");

1128

}

1129

return false;

1130

}

1131

return true;

1132

}

1133

1134

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

1135

1136

/* Reject the loopback device */

1137

if(ifr->ifr_flags & IFF_LOOPBACK){

1138

if(debug){

1139

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

1140

ifname);

1141

}

1142

return false;

1143

}

1144

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

1145

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

1146

if(debug){

1147

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

1148

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

1149

}

1150

return true;

1151

}

1152

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

1153

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

1154

if(debug){

1155

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1156

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

1157

}

1158

return false;

1159

}

1160

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

1161

if(ifr->ifr_flags & IFF_NOARP){

1162

if(debug){

1163

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

1164

ifname);

1165

}

1166

return false;

1167

}

1168

1169

/* Accept this device */

1170

if(debug){

1171

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

1172

}

1173

return true;

1174

}

1175

1176

/*

1177

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

1178

* corresponds to an acceptable network device.

1179

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

1180

*/

1181

int good_interface(const struct dirent *if_entry){

1182

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

1183

return 0;

1184

}

1185

1186

struct ifreq ifr;

1187

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

1188

if(debug){

1189

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

1190

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

1191

}

1192

return 0;

1193

}

1194

1195

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

1196

return 0;

1197

}

1198

return 1;

1199

}

1200

1201

/*

1202

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

1203

* corresponds to an acceptable network device which is up.

1204

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

1205

*/

1206

int up_interface(const struct dirent *if_entry){

1207

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

1208

return 0;

1209

}

1210

1211

struct ifreq ifr;

1212

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

1213

if(debug){

1214

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

1215

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

1216

}

1217

return 0;

1218

}

1219

1220

/* Reject down interfaces */

1221

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

1222

if(debug){

1223

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

1224

if_entry->d_name);

1225

}

1226

return 0;

1227

}

1228

1229

/* Reject non-running interfaces */

1230

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

1231

if(debug){

1232

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

1233

if_entry->d_name);

1234

}

1235

return 0;

1236

}

1237

1238

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

1239

return 0;

1240

}

1241

return 1;

1242

}

1243

1244

int notdotentries(const struct dirent *direntry){

1245

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

1246

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

1247

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

1248

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

1249

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

1250

return 0;

1251

}

1252

return 1;

1253

}

1254

1255

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

1256

int runnable_hook(const struct dirent *direntry){

1257

int ret;

1258

size_t sret;

1259

struct stat st;

1260

1261

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

1262

/* Empty name? */

1263

return 0;

1264

}

1265

1266

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

1267

"abcdefghijklmnopqrstuvwxyz"

1268

"0123456789"

1269

"_-");

1270

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

1271

/* Contains non-allowed characters */

1272

if(debug){

1273

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

1274

direntry->d_name);

1275

}

1276

return 0;

1277

}

1278

1279

char *fullname = NULL;

1280

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

1281

if(ret < 0){

1282

perror_plus("asprintf");

1283

return 0;

1284

}

1285

1286

ret = stat(fullname, &st);

1287

if(ret == -1){

1288

if(debug){

1289

perror_plus("Could not stat hook");

1290

}

1291

return 0;

1292

}

1293

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

1294

/* Not a regular file */

1295

if(debug){

1296

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

1297

direntry->d_name);

1298

}

1299

return 0;

1300

}

1301

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

1302

/* Not executable */

1303

if(debug){

1304

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

1305

direntry->d_name);

1306

}

1307

return 0;

1308

}

1309

if(debug){

1310

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

1311

direntry->d_name);

1312

}

1313

return 1;

1314

}

1315

1316

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1317

int ret;

1318

struct timespec now;

1319

struct timespec waited_time;

1320

intmax_t block_time;

1321

1322

while(true){

1323

if(mc.current_server == NULL){

1324

if (debug){

1325

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

1326

" No timeout!\n");

1327

}

1328

ret = avahi_simple_poll_iterate(s, -1);

1329

} else {

1330

if (debug){

1331

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

1332

" it, or wait\n");

1333

}

1334

/* the current time */

1335

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1336

if(ret == -1){

1337

perror_plus("clock_gettime");

1338

return -1;

1339

}

1340

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

1341

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

1342

waited_time.tv_sec = (now.tv_sec

1343

- mc.current_server->last_seen.tv_sec);

1344

waited_time.tv_nsec = (now.tv_nsec

1345

- mc.current_server->last_seen.tv_nsec);

1346

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

1347

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

1348

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

1349

block_time = ((retry_interval

1350

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

1351

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

1352

1353

if (debug){

1354

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

1355

block_time);

1356

}

1357

1358

if(block_time <= 0){

1359

ret = start_mandos_communication(mc.current_server->ip,

1360

mc.current_server->port,

1361

mc.current_server->if_index,

1362

mc.current_server->af);

1363

if(ret == 0){

1364

avahi_simple_poll_quit(mc.simple_poll);

1365

return 0;

1366

}

1367

ret = clock_gettime(CLOCK_MONOTONIC,

1368

&mc.current_server->last_seen);

1369

if(ret == -1){

1370

perror_plus("clock_gettime");

1371

return -1;

1372

}

1373

mc.current_server = mc.current_server->next;

1374

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

1375

servers, but don't block */

1376

}

1377

1378

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

1379

}

1380

if(ret != 0){

1381

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

1382

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

1383

}

1384

}

1385

}

1386

}

1387

1388

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

1389

const float delay){

1390

struct dirent **direntries;

1391

struct dirent *direntry;

1392

int ret;

1393

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

1394

alphasort);

1395

if(numhooks == -1){

1396

perror_plus("scandir");

1397

} else {

1398

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

1399

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

1400

direntry = direntries[i];

1401

char *fullname = NULL;

1402

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

1403

if(ret < 0){

1404

perror_plus("asprintf");

1405

continue;

1406

}

1407

if(debug){

1408

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

1409

direntry->d_name);

1410

}

1411

pid_t hook_pid = fork();

1412

if(hook_pid == 0){

1413

/* Child */

1414

/* Raise privileges */

1415

errno = 0;

1416

ret = seteuid(0);

1417

if(ret == -1){

1418

perror_plus("seteuid");

1419

}

1420

/* Raise privileges even more */

1421

errno = 0;

1422

ret = setuid(0);

1423

if(ret == -1){

1424

perror_plus("setuid");

1425

}

1426

/* Set group */

1427

errno = 0;

1428

ret = setgid(0);

1429

if(ret == -1){

1430

perror_plus("setgid");

1431

}

1432

/* Reset supplementary groups */

1433

errno = 0;

1434

ret = setgroups(0, NULL);

1435

if(ret == -1){

1436

perror_plus("setgroups");

1437

}

1438

dup2(devnull, STDIN_FILENO);

1439

close(devnull);

1440

dup2(STDERR_FILENO, STDOUT_FILENO);

1441

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

1442

if(ret == -1){

1443

perror_plus("setenv");

1444

_exit(EX_OSERR);

1445

}

1446

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

1447

if(ret == -1){

1448

perror_plus("setenv");

1449

_exit(EX_OSERR);

1450

}

1451

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

1452

if(ret == -1){

1453

perror_plus("setenv");

1454

_exit(EX_OSERR);

1455

}

1456

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

1457

if(ret == -1){

1458

perror_plus("setenv");

1459

_exit(EX_OSERR);

1460

}

1461

char *delaystring;

1462

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

1463

if(ret == -1){

1464

perror_plus("asprintf");

1465

_exit(EX_OSERR);

1466

}

1467

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

1468

if(ret == -1){

1469

free(delaystring);

1470

perror_plus("setenv");

1471

_exit(EX_OSERR);

1472

}

1473

free(delaystring);

1474

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

1475

perror_plus("execl");

1476

_exit(EXIT_FAILURE);

1477

}

1478

} else {

1479

int status;

1480

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

1481

perror_plus("waitpid");

1482

free(fullname);

1483

continue;

1484

}

1485

if(WIFEXITED(status)){

1486

if(WEXITSTATUS(status) != 0){

1487

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

1488

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

1489

WEXITSTATUS(status));

1490

free(fullname);

1491

continue;

1492

}

1493

} else if(WIFSIGNALED(status)){

1494

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

1495

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

1496

WTERMSIG(status));

1497

free(fullname);

1498

continue;

1499

} else {

1500

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

1501

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

1502

free(fullname);

1503

continue;

1504

}

1505

}

1506

free(fullname);

1507

if(debug){

1508

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

1509

direntry->d_name);

1510

}

1511

}

1512

close(devnull);

1513

}

1514

return true;

1515

}

1516

1517

873

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

1518

874

AvahiSServiceBrowser *sb = NULL;

1519

875

int error;

1520

876

int ret;

1521

877

intmax_t tmpmax;

1522

char *tmp;

878

int numchars;

1523

879

int exitcode = EXIT_SUCCESS;

1524

const char *interface = "";

880

const char *interface = "eth0";

1525

881

struct ifreq network;

1526

int sd = -1;

1527

bool take_down_interface = false;

882

int sd;

1528

883

uid_t uid;

1529

884

gid_t gid;

885

char *connect_to = NULL;

1530

886

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

1531

887

bool tempdir_created = false;

1532

888

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1533

889

const char *seckey = PATHDIR "/" SECKEY;

1534

890

const char *pubkey = PATHDIR "/" PUBKEY;

1535

891

892

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

893

.dh_bits = 1024, .priority = "SECURE256"

894

":!CTYPE-X.509:+CTYPE-OPENPGP" };

1536

895

bool gnutls_initialized = false;

1537

896

bool gpgme_initialized = false;

1538

float delay = 2.5f;

1539

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

1540

retrying the same server again */

1541

1542

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1543

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1544

1545

uid = getuid();

1546

gid = getgid();

1547

1548

/* Lower any group privileges we might have, just to be safe */

1549

errno = 0;

1550

ret = setgid(gid);

1551

if(ret == -1){

1552

perror_plus("setgid");

1553

}

1554

1555

/* Lower user privileges (temporarily) */

1556

errno = 0;

1557

ret = seteuid(uid);

1558

if(ret == -1){

1559

perror_plus("seteuid");

1560

}

1561

1562

if(quit_now){

1563

goto end;

1564

}

897

double delay = 2.5;

1565

898

1566

899

{

1567

900

struct argp_option options[] = {

1597

930

.arg = "SECONDS",

1598

931

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

1599

932

.group = 2 },

1600

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

1601

.arg = "SECONDS",

1602

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

1603

.group = 2 },

1604

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

1605

.arg = "DIR",

1606

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

1607

.group = 2 },

1608

/*

1609

* These reproduce what we would get without ARGP_NO_HELP

1610

*/

1611

{ .name = "help", .key = '?',

1612

.doc = "Give this help list", .group = -1 },

1613

{ .name = "usage", .key = -3,

1614

.doc = "Give a short usage message", .group = -1 },

1615

{ .name = "version", .key = 'V',

1616

.doc = "Print program version", .group = -1 },

1617

933

{ .name = NULL }

1618

934

};

1619

935

1620

936

error_t parse_opt(int key, char *arg,

1621

937

struct argp_state *state){

1622

errno = 0;

1623

938

switch(key){

1624

939

case 128: /* --debug */

1625

940

debug = true;

1637

952

pubkey = arg;

1638

953

break;

1639

954

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

1640

errno = 0;

1641

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

1642

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

1643

or tmpmax != (typeof(mc.dh_bits))tmpmax){

1644

argp_error(state, "Bad number of DH bits");

955

ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);

956

if(ret < 1 or tmpmax != (typeof(mc.dh_bits))tmpmax

957

or arg[numchars] != '\0'){

958

fprintf(stderr, "Bad number of DH bits\n");

959

exit(EXIT_FAILURE);

1645

960

}

1646

961

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

1647

962

break;

1649

964

mc.priority = arg;

1650

965

break;

1651

966

case 131: /* --delay */

1652

errno = 0;

1653

delay = strtof(arg, &tmp);

1654

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

1655

argp_error(state, "Bad delay");

1656

}

1657

case 132: /* --retry */

1658

errno = 0;

1659

retry_interval = strtod(arg, &tmp);

1660

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

1661

or (retry_interval * 1000) > INT_MAX

1662

or retry_interval < 0){

1663

argp_error(state, "Bad retry interval");

1664

}

1665

break;

1666

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

1667

hookdir = arg;

1668

break;

1669

/*

1670

* These reproduce what we would get without ARGP_NO_HELP

1671

*/

1672

case '?': /* --help */

1673

argp_state_help(state, state->out_stream,

1674

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

1675

& ~(unsigned int)ARGP_HELP_EXIT_OK);

1676

case -3: /* --usage */

1677

argp_state_help(state, state->out_stream,

1678

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1679

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

1680

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

1681

exit(argp_err_exit_status);

967

ret = sscanf(arg, "%lf%n", &delay, &numchars);

968

if(ret < 1 or arg[numchars] != '\0'){

969

fprintf(stderr, "Bad delay\n");

970

exit(EXIT_FAILURE);

971

}

972

break;

973

case ARGP_KEY_ARG:

974

argp_usage(state);

975

case ARGP_KEY_END:

1682

976

break;

1683

977

default:

1684

978

return ARGP_ERR_UNKNOWN;

1685

979

}

1686

return errno;

980

return 0;

1687

981

}

1688

982

1689

983

struct argp argp = { .options = options, .parser = parse_opt,

1690

984

.args_doc = "",

1691

985

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

1692

986

" passwords from a Mandos server" };

1693

ret = argp_parse(&argp, argc, argv,

1694

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1695

switch(ret){

1696

case 0:

1697

break;

1698

case ENOMEM:

1699

default:

1700

errno = ret;

1701

perror_plus("argp_parse");

1702

exitcode = EX_OSERR;

1703

goto end;

1704

case EINVAL:

1705

exitcode = EX_USAGE;

1706

goto end;

1707

}

1708

}

1709

1710

{

1711

/* Work around Debian bug #633582:

1712

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

1713

1714

/* Re-raise priviliges */

1715

errno = 0;

1716

ret = seteuid(0);

1717

if(ret == -1){

1718

perror_plus("seteuid");

1719

} else {

1720

struct stat st;

1721

1722

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

1723

int seckey_fd = open(seckey, O_RDONLY);

1724

if(seckey_fd == -1){

1725

perror_plus("open");

1726

} else {

1727

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

1728

if(ret == -1){

1729

perror_plus("fstat");

1730

} else {

1731

if(S_ISREG(st.st_mode)

1732

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

1733

ret = fchown(seckey_fd, uid, gid);

1734

if(ret == -1){

1735

perror_plus("fchown");

1736

}

1737

}

1738

}

1739

TEMP_FAILURE_RETRY(close(seckey_fd));

1740

}

1741

}

1742

1743

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

1744

int pubkey_fd = open(pubkey, O_RDONLY);

1745

if(pubkey_fd == -1){

1746

perror_plus("open");

1747

} else {

1748

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

1749

if(ret == -1){

1750

perror_plus("fstat");

1751

} else {

1752

if(S_ISREG(st.st_mode)

1753

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

1754

ret = fchown(pubkey_fd, uid, gid);

1755

if(ret == -1){

1756

perror_plus("fchown");

1757

}

1758

}

1759

}

1760

TEMP_FAILURE_RETRY(close(pubkey_fd));

1761

}

1762

}

1763

1764

/* Lower privileges */

1765

errno = 0;

1766

ret = seteuid(uid);

1767

if(ret == -1){

1768

perror_plus("seteuid");

1769

}

1770

}

1771

}

1772

1773

/* Run network hooks */

1774

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

1775

goto end;

1776

}

1777

1778

if(not debug){

1779

avahi_set_log_function(empty_log);

1780

}

1781

1782

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

1783

struct dirent **direntries;

1784

/* First look for interfaces that are up */

1785

ret = scandir(sys_class_net, &direntries, up_interface,

1786

alphasort);

1787

if(ret == 0){

1788

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

1789

free(direntries);

1790

ret = scandir(sys_class_net, &direntries, good_interface,

1791

alphasort);

1792

}

1793

if(ret >= 1){

1794

/* Pick the first interface returned */

1795

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

1796

if(debug){

1797

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

1798

}

1799

if(interface == NULL){

1800

perror_plus("malloc");

1801

free(direntries);

1802

exitcode = EXIT_FAILURE;

1803

goto end;

1804

}

1805

free(direntries);

1806

} else {

1807

free(direntries);

1808

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

987

ret = argp_parse(&argp, argc, argv, 0, 0, NULL);

988

if(ret == ARGP_ERR_UNKNOWN){

989

fprintf(stderr, "Unknown error while parsing arguments\n");

1809

990

exitcode = EXIT_FAILURE;

1810

991

goto end;

1811

992

}

1812

993

}

1813

994

1814

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

1815

from the signal handler */

1816

/* Initialize the pseudo-RNG for Avahi */

1817

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

1818

mc.simple_poll = avahi_simple_poll_new();

1819

if(mc.simple_poll == NULL){

1820

fprintf_plus(stderr,

1821

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

1822

exitcode = EX_UNAVAILABLE;

1823

goto end;

1824

}

1825

1826

sigemptyset(&sigterm_action.sa_mask);

1827

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

1828

if(ret == -1){

1829

perror_plus("sigaddset");

1830

exitcode = EX_OSERR;

1831

goto end;

1832

}

1833

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

1834

if(ret == -1){

1835

perror_plus("sigaddset");

1836

exitcode = EX_OSERR;

1837

goto end;

1838

}

1839

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

1840

if(ret == -1){

1841

perror_plus("sigaddset");

1842

exitcode = EX_OSERR;

1843

goto end;

1844

}

1845

/* Need to check if the handler is SIG_IGN before handling:

1846

| [[info:libc:Initial Signal Actions]] |

1847

| [[info:libc:Basic Signal Handling]] |

1848

*/

1849

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

1850

if(ret == -1){

1851

perror_plus("sigaction");

1852

return EX_OSERR;

1853

}

1854

if(old_sigterm_action.sa_handler != SIG_IGN){

1855

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

1856

if(ret == -1){

1857

perror_plus("sigaction");

1858

exitcode = EX_OSERR;

1859

goto end;

1860

}

1861

}

1862

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

1863

if(ret == -1){

1864

perror_plus("sigaction");

1865

return EX_OSERR;

1866

}

1867

if(old_sigterm_action.sa_handler != SIG_IGN){

1868

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

1869

if(ret == -1){

1870

perror_plus("sigaction");

1871

exitcode = EX_OSERR;

1872

goto end;

1873

}

1874

}

1875

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

1876

if(ret == -1){

1877

perror_plus("sigaction");

1878

return EX_OSERR;

1879

}

1880

if(old_sigterm_action.sa_handler != SIG_IGN){

1881

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

1882

if(ret == -1){

1883

perror_plus("sigaction");

1884

exitcode = EX_OSERR;

1885

goto end;

1886

}

1887

}

1888

1889

995

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

1890

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

1891

if_index = (AvahiIfIndex) if_nametoindex(interface);

1892

if(if_index == 0){

1893

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

1894

exitcode = EX_UNAVAILABLE;

1895

goto end;

1896

}

1897

1898

if(quit_now){

1899

goto end;

1900

}

1901

1902

/* Re-raise priviliges */

1903

errno = 0;

1904

ret = seteuid(0);

1905

if(ret == -1){

1906

perror_plus("seteuid");

1907

}

1908

996

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

1909

997

#ifdef __linux__

1910

998

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1911

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

999

messages to mess up the prompt */

1912

1000

ret = klogctl(8, NULL, 5);

1913

1001

bool restore_loglevel = true;

1914

1002

if(ret == -1){

1915

1003

restore_loglevel = false;

1916

perror_plus("klogctl");

1004

perror("klogctl");

1917

1005

}

1918

#endif /* __linux__ */

1006

#endif

1919

1007

1920

1008

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1921

1009

if(sd < 0){

1922

perror_plus("socket");

1923

exitcode = EX_OSERR;

1010

perror("socket");

1011

exitcode = EXIT_FAILURE;

1924

1012

#ifdef __linux__

1925

1013

if(restore_loglevel){

1926

1014

ret = klogctl(7, NULL, 0);

1927

1015

if(ret == -1){

1928

perror_plus("klogctl");

1016

perror("klogctl");

1929

1017

}

1930

1018

}

1931

#endif /* __linux__ */

1932

/* Lower privileges */

1933

errno = 0;

1934

ret = seteuid(uid);

1935

if(ret == -1){

1936

perror_plus("seteuid");

1937

}

1019

#endif

1938

1020

goto end;

1939

1021

}

1940

1022

strcpy(network.ifr_name, interface);

1941

1023

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

1942

1024

if(ret == -1){

1943

perror_plus("ioctl SIOCGIFFLAGS");

1025

perror("ioctl SIOCGIFFLAGS");

1944

1026

#ifdef __linux__

1945

1027

if(restore_loglevel){

1946

1028

ret = klogctl(7, NULL, 0);

1947

1029

if(ret == -1){

1948

perror_plus("klogctl");

1030

perror("klogctl");

1949

1031

}

1950

1032

}

1951

#endif /* __linux__ */

1952

exitcode = EX_OSERR;

1953

/* Lower privileges */

1954

errno = 0;

1955

ret = seteuid(uid);

1956

if(ret == -1){

1957

perror_plus("seteuid");

1958

}

1033

#endif

1034

exitcode = EXIT_FAILURE;

1959

1035

goto end;

1960

1036

}

1961

1037

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

1962

1038

network.ifr_flags |= IFF_UP;

1963

take_down_interface = true;

1964

1039

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

1965

1040

if(ret == -1){

1966

take_down_interface = false;

1967

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1968

exitcode = EX_OSERR;

1041

perror("ioctl SIOCSIFFLAGS");

1042

exitcode = EXIT_FAILURE;

1969

1043

#ifdef __linux__

1970

1044

if(restore_loglevel){

1971

1045

ret = klogctl(7, NULL, 0);

1972

1046

if(ret == -1){

1973

perror_plus("klogctl");

1047

perror("klogctl");

1974

1048

}

1975

1049

}

1976

#endif /* __linux__ */

1977

/* Lower privileges */

1978

errno = 0;

1979

ret = seteuid(uid);

1980

if(ret == -1){

1981

perror_plus("seteuid");

1982

}

1050

#endif

1983

1051

goto end;

1984

1052

}

1985

1053

}

1986

/* Sleep checking until interface is running.

1987

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

1054

/* sleep checking until interface is running */

1988

1055

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

1989

1056

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

1990

1057

if(ret == -1){

1991

perror_plus("ioctl SIOCGIFFLAGS");

1058

perror("ioctl SIOCGIFFLAGS");

1992

1059

} else if(network.ifr_flags & IFF_RUNNING){

1993

1060

break;

1994

1061

}

1995

1062

struct timespec sleeptime = { .tv_nsec = 250000000 };

1996

1063

ret = nanosleep(&sleeptime, NULL);

1997

1064

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

1998

perror_plus("nanosleep");

1065

perror("nanosleep");

1999

1066

}

2000

1067

}

2001

if(not take_down_interface){

2002

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

2003

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

2004

if(ret == -1){

2005

perror_plus("close");

2006

}

1068

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

1069

if(ret == -1){

1070

perror("close");

2007

1071

}

2008

1072

#ifdef __linux__

2009

1073

if(restore_loglevel){

2010

1074

/* Restores kernel loglevel to default */

2011

1075

ret = klogctl(7, NULL, 0);

2012

1076

if(ret == -1){

2013

perror_plus("klogctl");

1077

perror("klogctl");

2014

1078

}

2015

1079

}

2016

#endif /* __linux__ */

2017

/* Lower privileges */

2018

errno = 0;

2019

/* Lower privileges */

2020

ret = seteuid(uid);

2021

if(ret == -1){

2022

perror_plus("seteuid");

2023

}

2024

}

2025

2026

if(quit_now){

2027

goto end;

2028

}

2029

2030

ret = init_gnutls_global(pubkey, seckey);

2031

if(ret == -1){

2032

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

2033

exitcode = EX_UNAVAILABLE;

1080

#endif

1081

}

1082

1083

uid = getuid();

1084

gid = getgid();

1085

1086

errno = 0;

1087

setgid(gid);

1088

if(ret == -1){

1089

perror("setgid");

1090

}

1091

1092

ret = setuid(uid);

1093

if(ret == -1){

1094

perror("setuid");

1095

}

1096

1097

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

1098

if(ret == -1){

1099

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

1100

exitcode = EXIT_FAILURE;

2034

1101

goto end;

2035

1102

} else {

2036

1103

gnutls_initialized = true;

2037

1104

}

2038

1105

2039

if(quit_now){

2040

goto end;

2041

}

2042

2043

1106

if(mkdtemp(tempdir) == NULL){

2044

perror_plus("mkdtemp");

1107

perror("mkdtemp");

2045

1108

goto end;

2046

1109

}

2047

1110

tempdir_created = true;

2048

1111

2049

if(quit_now){

2050

goto end;

2051

}

2052

2053

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

2054

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

2055

exitcode = EX_UNAVAILABLE;

1112

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

1113

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

1114

exitcode = EXIT_FAILURE;

2056

1115

goto end;

2057

1116

} else {

2058

1117

gpgme_initialized = true;

2059

1118

}

2060

1119

2061

if(quit_now){

2062

goto end;

1120

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

1121

if_index = (AvahiIfIndex) if_nametoindex(interface);

1122

if(if_index == 0){

1123

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

1124

exitcode = EXIT_FAILURE;

1125

goto end;

1126

}

2063

1127

}

2064

1128

2065

1129

if(connect_to != NULL){

2067

1131

/* (Mainly meant for debugging) */

2068

1132

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

2069

1133

if(address == NULL){

2070

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

2071

exitcode = EX_USAGE;

2072

goto end;

2073

}

2074

2075

if(quit_now){

2076

goto end;

2077

}

2078

1134

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

1135

exitcode = EXIT_FAILURE;

1136

goto end;

1137

}

2079

1138

uint16_t port;

2080

errno = 0;

2081

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

2082

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

2083

or tmpmax != (uint16_t)tmpmax){

2084

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

2085

exitcode = EX_USAGE;

2086

goto end;

2087

}

2088

2089

if(quit_now){

2090

goto end;

2091

}

2092

1139

ret = sscanf(address+1, "%" SCNdMAX "%n", &tmpmax, &numchars);

1140

if(ret < 1 or tmpmax != (uint16_t)tmpmax

1141

or address[numchars+1] != '\0'){

1142

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

1143

exitcode = EXIT_FAILURE;

1144

goto end;

1145

}

2093

1146

port = (uint16_t)tmpmax;

2094

1147

*address = '\0';

1148

address = connect_to;

2095

1149

/* Colon in address indicates IPv6 */

2096

1150

int af;

2097

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

1151

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

2098

1152

af = AF_INET6;

2099

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

2100

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

2101

{

2102

connect_to++;

2103

address[-1] = '\0';

2104

}

2105

1153

} else {

2106

1154

af = AF_INET;

2107

1155

}

2108

address = connect_to;

2109

2110

if(quit_now){

2111

goto end;

2112

}

2113

2114

while(not quit_now){

2115

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

2116

if(quit_now or ret == 0){

2117

break;

2118

}

2119

if(debug){

2120

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

2121

(int)retry_interval);

2122

}

2123

sleep((int)retry_interval);

2124

}

2125

2126

if (not quit_now){

1156

ret = start_mandos_communication(address, port, if_index, &mc,

1157

af);

1158

if(ret < 0){

1159

exitcode = EXIT_FAILURE;

1160

} else {

2127

1161

exitcode = EXIT_SUCCESS;

2128

1162

}

2129

2130

1163

goto end;

2131

1164

}

2132

1165

2133

if(quit_now){

1166

if(not debug){

1167

avahi_set_log_function(empty_log);

1168

}

1169

1170

/* Initialize the pseudo-RNG for Avahi */

1171

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

1172

1173

/* Allocate main Avahi loop object */

1174

mc.simple_poll = avahi_simple_poll_new();

1175

if(mc.simple_poll == NULL){

1176

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

1177

exitcode = EXIT_FAILURE;

2134

1178

goto end;

2135

1179

}

2136

1180

2154

1198

2155

1199

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

2156

1200

if(mc.server == NULL){

2157

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

2158

avahi_strerror(error));

2159

exitcode = EX_UNAVAILABLE;

2160

goto end;

2161

}

2162

2163

if(quit_now){

1201

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

1202

avahi_strerror(error));

1203

exitcode = EXIT_FAILURE;

2164

1204

goto end;

2165

1205

}

2166

1206

2167

1207

/* Create the Avahi service browser */

2168

1208

sb = avahi_s_service_browser_new(mc.server, if_index,

2169

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2170

NULL, 0, browse_callback, NULL);

1209

AVAHI_PROTO_INET6, "_mandos._tcp",

1210

NULL, 0, browse_callback, &mc);

2171

1211

if(sb == NULL){

2172

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

2173

avahi_strerror(avahi_server_errno(mc.server)));

2174

exitcode = EX_UNAVAILABLE;

2175

goto end;

2176

}

2177

2178

if(quit_now){

1212

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

1213

avahi_strerror(avahi_server_errno(mc.server)));

1214

exitcode = EXIT_FAILURE;

2179

1215

goto end;

2180

1216

}

2181

1217

2182

1218

/* Run the main loop */

2183

1219

2184

1220

if(debug){

2185

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

2186

}

2187

2188

ret = avahi_loop_with_timeout(mc.simple_poll,

2189

(int)(retry_interval * 1000));

2190

if(debug){

2191

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

2192

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

2193

}

1221

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

1222

}

1223

1224

avahi_simple_poll_loop(mc.simple_poll);

2194

1225

2195

1226

end:

2196

1227

2197

1228

if(debug){

2198

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

1229

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

2199

1230

}

2200

1231

2201

1232

/* Cleanup things */

2218

1249

gpgme_release(mc.ctx);

2219

1250

}

2220

1251

2221

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

2222

has seen */

2223

if(mc.current_server != NULL){

2224

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

2225

while(mc.current_server != NULL){

2226

server *next = mc.current_server->next;

2227

free(mc.current_server);

2228

mc.current_server = next;

2229

}

2230

}

2231

2232

/* Run network hooks */

2233

run_network_hooks("stop", interface, delay);

2234

2235

/* Re-raise priviliges */

2236

{

2237

errno = 0;

2238

ret = seteuid(0);

2239

if(ret == -1){

2240

perror_plus("seteuid");

2241

}

2242

2243

/* Take down the network interface */

2244

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

2245

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

2246

if(ret == -1){

2247

perror_plus("ioctl SIOCGIFFLAGS");

2248

} else if(network.ifr_flags & IFF_UP){

2249

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

2250

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

2251

if(ret == -1){

2252

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2253

}

2254

}

2255

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

2256

if(ret == -1){

2257

perror_plus("close");

2258

}

2259

}

2260

}

2261

/* Lower privileges permanently */

2262

errno = 0;

2263

ret = setuid(uid);

2264

if(ret == -1){

2265

perror_plus("setuid");

2266

}

2267

2268

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

1252

/* Removes the temp directory used by GPGME */

2269

1253

if(tempdir_created){

2270

struct dirent **direntries = NULL;

2271

struct dirent *direntry = NULL;

2272

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

2273

alphasort);

2274

if (numentries > 0){

2275

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

2276

direntry = direntries[i];

1254

DIR *d;

1255

struct dirent *direntry;

1256

d = opendir(tempdir);

1257

if(d == NULL){

1258

if(errno != ENOENT){

1259

perror("opendir");

1260

}

1261

} else {

1262

while(true){

1263

direntry = readdir(d);

1264

if(direntry == NULL){

1265

break;

1266

}

1267

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

1268

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

1269

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

1270

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

1271

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

1272

continue;

1273

}

2277

1274

char *fullname = NULL;

2278

1275

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

2279

1276

direntry->d_name);

2280

1277

if(ret < 0){

2281

perror_plus("asprintf");

1278

perror("asprintf");

2282

1279

continue;

2283

1280

}

2284

1281

ret = remove(fullname);

2285

1282

if(ret == -1){

2286

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

2287

strerror(errno));

1283

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

1284

strerror(errno));

2288

1285

}

2289

1286

free(fullname);

2290

1287

}

2291

}

2292

2293

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

2294

free(direntries);

2295

if (numentries == -1){

2296

perror_plus("scandir");

1288

closedir(d);

2297

1289

}

2298

1290

ret = rmdir(tempdir);

2299

1291

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

2300

perror_plus("rmdir");

2301

}

2302

}

2303

2304

if(quit_now){

2305

sigemptyset(&old_sigterm_action.sa_mask);

2306

old_sigterm_action.sa_handler = SIG_DFL;

2307

ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,

2308

&old_sigterm_action,

2309

NULL));

2310

if(ret == -1){

2311

perror_plus("sigaction");

2312

}

2313

do {

2314

ret = raise(signal_received);

2315

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

2316

if(ret != 0){

2317

perror_plus("raise");

2318

abort();

2319

}

2320

TEMP_FAILURE_RETRY(pause());

1292

perror("rmdir");

1293

}

2321

1294

}

2322

1295

2323

1296

return exitcode;