/mandos/release : revision 237.2.118

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

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stdout, ferror(), remove() */

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

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#include <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(), strtof() */

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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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*/

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

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strtoimax() */

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

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program_invocation_short_name */

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

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

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

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

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

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SIOCSIFFLAGS, if_indextoname(),

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if_nametoindex(), IF_NAMESIZE */

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

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sigaction(), SIGTERM, sig_atomic_t,

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raise() */

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

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EX_NOHOST, EX_IOERR, EX_PROTOCOL */

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

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WEXITSTATUS(), WTERMSIG() */

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

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

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argz_delete(), argz_append(),

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argz_stringify(), argz_add(),

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argz_count() */

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#ifdef __linux__

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

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105

init_gnutls_session(),

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106

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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121

#define SECKEY "seckey.txt"

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122

#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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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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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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AvahiSimplePoll *simple_poll;

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AvahiServer *server;

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gnutls_certificate_credentials_t cred;

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unsigned int dh_bits;

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gnutls_dh_params_t dh_params;

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const char *priority;

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gpgme_ctx_t ctx;

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server *current_server;

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} mandos_context;

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/* global so signal handler can reach it*/

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AvahiSimplePoll *simple_poll;

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

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

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"+CTYPE-OPENPGP", .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;

181

perror(print_text);

182

}

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184

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

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

186

va_list ap;

187

va_start (ap, format);

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189

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

190

program_invocation_short_name));

191

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

192

}

140

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

141

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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/*

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

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* "buffer_length" is how much is already used.

198

149

*/

199

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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 buffer_capacity){

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if(buffer_length + BUFFER_SIZE > buffer_capacity){

202

153

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

203

154

if(buffer == NULL){

208

159

return buffer_capacity;

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160

}

210

161

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

212

bool add_server(const char *ip, in_port_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){

217

perror_plus("malloc");

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return false;

219

}

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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){

225

perror_plus("strdup");

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return false;

227

}

228

/* Special case of first server */

229

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;

239

}

240

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

241

if(ret == -1){

242

perror_plus("clock_gettime");

243

return false;

244

}

245

return true;

246

}

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248

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/*

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163

* Initialize GPGME.

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164

*/

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

252

const char *tempdir){

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static bool init_gpgme(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;

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gpgme_engine_info_t engine_info;

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256

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/*

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

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174

*/

259

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bool import_key(const char *filename){

260

int ret;

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int fd;

262

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gpgme_data_t pgp_data;

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

265

180

if(fd == -1){

266

perror_plus("open");

181

perror("open");

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182

return false;

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183

}

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rc = gpgme_data_new_from_fd(&pgp_data, fd);

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if(rc != GPG_ERR_NO_ERROR){

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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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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){

286

perror_plus("close");

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perror("close");

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}

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203

gpgme_data_release(pgp_data);

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return true;

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}

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if(debug){

293

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

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

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}

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/* Init GPGME */

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gpgme_check_version(NULL);

298

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rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

299

214

if(rc != GPG_ERR_NO_ERROR){

300

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

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gpgme_strsource(rc), gpgme_strerror(rc));

215

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

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gpgme_strsource(rc), gpgme_strerror(rc));

302

217

return false;

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218

}

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219

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

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

306

221

rc = gpgme_get_engine_info(&engine_info);

307

222

if(rc != GPG_ERR_NO_ERROR){

308

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

309

gpgme_strsource(rc), gpgme_strerror(rc));

223

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

224

gpgme_strsource(rc), gpgme_strerror(rc));

310

225

return false;

311

226

}

312

227

while(engine_info != NULL){

318

233

engine_info = engine_info->next;

319

234

}

320

235

if(engine_info == NULL){

321

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

322

tempdir);

236

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

323

237

return false;

324

238

}

325

239

326

240

/* Create new GPGME "context" */

327

241

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

328

242

if(rc != GPG_ERR_NO_ERROR){

329

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

330

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

331

gpgme_strerror(rc));

243

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

244

gpgme_strsource(rc), gpgme_strerror(rc));

332

245

return false;

333

246

}

334

247

353

266

ssize_t plaintext_length = 0;

354

267

355

268

if(debug){

356

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

269

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

357

270

}

358

271

359

272

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

360

273

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

361

274

0);

362

275

if(rc != GPG_ERR_NO_ERROR){

363

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

364

gpgme_strsource(rc), gpgme_strerror(rc));

276

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

277

gpgme_strsource(rc), gpgme_strerror(rc));

365

278

return -1;

366

279

}

367

280

368

281

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

369

282

rc = gpgme_data_new(&dh_plain);

370

283

if(rc != GPG_ERR_NO_ERROR){

371

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

372

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

373

gpgme_strsource(rc), gpgme_strerror(rc));

284

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

285

gpgme_strsource(rc), gpgme_strerror(rc));

374

286

gpgme_data_release(dh_crypto);

375

287

return -1;

376

288

}

379

291

data buffer */

380

292

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

381

293

if(rc != GPG_ERR_NO_ERROR){

382

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

383

gpgme_strsource(rc), gpgme_strerror(rc));

294

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

295

gpgme_strsource(rc), gpgme_strerror(rc));

384

296

plaintext_length = -1;

385

297

if(debug){

386

298

gpgme_decrypt_result_t result;

387

299

result = gpgme_op_decrypt_result(mc.ctx);

388

300

if(result == NULL){

389

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

301

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

390

302

} else {

391

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

392

result->unsupported_algorithm);

393

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

394

result->wrong_key_usage);

303

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

304

result->unsupported_algorithm);

305

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

306

result->wrong_key_usage);

395

307

if(result->file_name != NULL){

396

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

308

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

397

309

}

398

310

gpgme_recipient_t recipient;

399

311

recipient = result->recipients;

400

312

while(recipient != NULL){

401

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

402

gpgme_pubkey_algo_name

403

(recipient->pubkey_algo));

404

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

405

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

406

recipient->status == GPG_ERR_NO_SECKEY

407

? "No" : "Yes");

313

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

314

gpgme_pubkey_algo_name(recipient->pubkey_algo));

315

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

316

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

317

recipient->status == GPG_ERR_NO_SECKEY

318

? "No" : "Yes");

408

319

recipient = recipient->next;

409

320

}

410

321

}

413

324

}

414

325

415

326

if(debug){

416

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

327

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

417

328

}

418

329

419

330

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

420

331

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

421

perror_plus("gpgme_data_seek");

332

perror("gpgme_data_seek");

422

333

plaintext_length = -1;

423

334

goto decrypt_end;

424

335

}

426

337

*plaintext = NULL;

427

338

while(true){

428

339

plaintext_capacity = incbuffer(plaintext,

429

(size_t)plaintext_length,

430

plaintext_capacity);

340

(size_t)plaintext_length,

341

plaintext_capacity);

431

342

if(plaintext_capacity == 0){

432

perror_plus("incbuffer");

433

plaintext_length = -1;

434

goto decrypt_end;

343

perror("incbuffer");

344

plaintext_length = -1;

345

goto decrypt_end;

435

346

}

436

347

437

348

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

442

353

break;

443

354

}

444

355

if(ret < 0){

445

perror_plus("gpgme_data_read");

356

perror("gpgme_data_read");

446

357

plaintext_length = -1;

447

358

goto decrypt_end;

448

359

}

450

361

}

451

362

452

363

if(debug){

453

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

364

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

454

365

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

455

366

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

456

367

}

468

379

}

469

380

470

381

static const char * safer_gnutls_strerror(int value){

471

const char *ret = gnutls_strerror(value);

382

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

383

-Wunreachable-code */

472

384

if(ret == NULL)

473

385

ret = "(unknown)";

474

386

return ret;

477

389

/* GnuTLS log function callback */

478

390

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

479

391

const char* string){

480

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

392

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

481

393

}

482

394

483

395

static int init_gnutls_global(const char *pubkeyfilename,

485

397

int ret;

486

398

487

399

if(debug){

488

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

400

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

489

401

}

490

402

491

403

ret = gnutls_global_init();

492

404

if(ret != GNUTLS_E_SUCCESS){

493

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

494

safer_gnutls_strerror(ret));

405

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

406

safer_gnutls_strerror(ret));

495

407

return -1;

496

408

}

497

409

504

416

}

505

417

506

418

/* OpenPGP credentials */

507

ret = gnutls_certificate_allocate_credentials(&mc.cred);

419

gnutls_certificate_allocate_credentials(&mc.cred);

508

420

if(ret != GNUTLS_E_SUCCESS){

509

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

510

safer_gnutls_strerror(ret));

421

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

422

from

423

-Wunreachable-code

424

*/

425

safer_gnutls_strerror(ret));

511

426

gnutls_global_deinit();

512

427

return -1;

513

428

}

514

429

515

430

if(debug){

516

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

517

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

518

pubkeyfilename,

519

seckeyfilename);

431

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

432

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

433

seckeyfilename);

520

434

}

521

435

522

436

ret = gnutls_certificate_set_openpgp_key_file

523

437

(mc.cred, pubkeyfilename, seckeyfilename,

524

438

GNUTLS_OPENPGP_FMT_BASE64);

525

439

if(ret != GNUTLS_E_SUCCESS){

526

fprintf_plus(stderr,

527

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

528

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

529

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

530

safer_gnutls_strerror(ret));

440

fprintf(stderr,

441

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

442

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

443

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

444

safer_gnutls_strerror(ret));

531

445

goto globalfail;

532

446

}

533

447

534

448

/* GnuTLS server initialization */

535

449

ret = gnutls_dh_params_init(&mc.dh_params);

536

450

if(ret != GNUTLS_E_SUCCESS){

537

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

538

" initialization: %s\n",

539

safer_gnutls_strerror(ret));

451

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

452

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

540

453

goto globalfail;

541

454

}

542

455

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

543

456

if(ret != GNUTLS_E_SUCCESS){

544

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

545

safer_gnutls_strerror(ret));

457

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

458

safer_gnutls_strerror(ret));

546

459

goto globalfail;

547

460

}

548

461

561

474

static int init_gnutls_session(gnutls_session_t *session){

562

475

int ret;

563

476

/* GnuTLS session creation */

564

do {

565

ret = gnutls_init(session, GNUTLS_SERVER);

566

if(quit_now){

567

return -1;

568

}

569

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

477

ret = gnutls_init(session, GNUTLS_SERVER);

570

478

if(ret != GNUTLS_E_SUCCESS){

571

fprintf_plus(stderr,

572

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

573

safer_gnutls_strerror(ret));

479

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

480

safer_gnutls_strerror(ret));

574

481

}

575

482

576

483

{

577

484

const char *err;

578

do {

579

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

580

if(quit_now){

581

gnutls_deinit(*session);

582

return -1;

583

}

584

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

485

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

585

486

if(ret != GNUTLS_E_SUCCESS){

586

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

587

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

588

safer_gnutls_strerror(ret));

487

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

488

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

489

safer_gnutls_strerror(ret));

589

490

gnutls_deinit(*session);

590

491

return -1;

591

492

}

592

493

}

593

494

594

do {

595

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

596

mc.cred);

597

if(quit_now){

598

gnutls_deinit(*session);

599

return -1;

600

}

601

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

495

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

496

mc.cred);

602

497

if(ret != GNUTLS_E_SUCCESS){

603

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

604

safer_gnutls_strerror(ret));

498

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

499

safer_gnutls_strerror(ret));

605

500

gnutls_deinit(*session);

606

501

return -1;

607

502

}

608

503

609

504

/* ignore client certificate if any. */

610

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

505

gnutls_certificate_server_set_request(*session,

506

GNUTLS_CERT_IGNORE);

611

507

612

508

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

613

509

618

514

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

619

515

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

620

516

517

sig_atomic_t quit_now = 0;

518

int signal_received = 0;

519

621

520

/* Called when a Mandos server is found */

622

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

521

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

623

522

AvahiIfIndex if_index,

624

523

int af){

625

int ret, tcp_sd = -1;

524

int ret, tcp_sd;

626

525

ssize_t sret;

627

526

union {

628

527

struct sockaddr_in in;

629

528

struct sockaddr_in6 in6;

630

529

} to;

631

530

char *buffer = NULL;

632

char *decrypted_buffer = NULL;

531

char *decrypted_buffer;

633

532

size_t buffer_length = 0;

634

533

size_t buffer_capacity = 0;

534

ssize_t decrypted_buffer_size;

635

535

size_t written;

636

int retval = -1;

536

int retval = 0;

637

537

gnutls_session_t session;

638

538

int pf; /* Protocol family */

639

539

640

errno = 0;

641

642

if(quit_now){

643

errno = EINTR;

644

return -1;

645

}

646

647

540

switch(af){

648

541

case AF_INET6:

649

542

pf = PF_INET6;

652

545

pf = PF_INET;

653

546

break;

654

547

default:

655

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

656

errno = EINVAL;

548

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

657

549

return -1;

658

550

}

659

551

663

555

}

664

556

665

557

if(debug){

666

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

667

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

558

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

559

"\n", ip, port);

668

560

}

669

561

670

562

tcp_sd = socket(pf, SOCK_STREAM, 0);

671

563

if(tcp_sd < 0){

672

int e = errno;

673

perror_plus("socket");

674

errno = e;

675

goto mandos_end;

676

}

677

678

if(quit_now){

679

errno = EINTR;

680

goto mandos_end;

564

perror("socket");

565

return -1;

681

566

}

682

567

683

568

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

689

574

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

690

575

}

691

576

if(ret < 0 ){

692

int e = errno;

693

perror_plus("inet_pton");

694

errno = e;

695

goto mandos_end;

577

perror("inet_pton");

578

return -1;

696

579

}

697

580

if(ret == 0){

698

int e = errno;

699

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

700

errno = e;

701

goto mandos_end;

581

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

582

return -1;

702

583

}

703

584

if(af == AF_INET6){

704

to.in6.sin6_port = htons(port);

585

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

586

-Wconversion and

587

-Wunreachable-code */

588

705

589

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

706

590

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

707

-Wunreachable-code*/

591

-Wunreachable-code*/

708

592

if(if_index == AVAHI_IF_UNSPEC){

709

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

710

" incomplete without a network interface\n");

711

errno = EINVAL;

712

goto mandos_end;

593

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

594

" without a network interface\n");

595

return -1;

713

596

}

714

597

/* Set the network interface number as scope */

715

598

to.in6.sin6_scope_id = (uint32_t)if_index;

720

603

-Wunreachable-code */

721

604

}

722

605

723

if(quit_now){

724

errno = EINTR;

725

goto mandos_end;

726

}

727

728

606

if(debug){

729

607

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

730

608

char interface[IF_NAMESIZE];

731

609

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

732

perror_plus("if_indextoname");

610

perror("if_indextoname");

733

611

} else {

734

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

735

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

612

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

613

ip, interface, port);

736

614

}

737

615

} else {

738

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

739

ip, (uintmax_t)port);

616

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

617

port);

740

618

}

741

619

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

742

620

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

749

627

sizeof(addrstr));

750

628

}

751

629

if(pcret == NULL){

752

perror_plus("inet_ntop");

630

perror("inet_ntop");

753

631

} else {

754

632

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

755

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

633

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

756

634

}

757

635

}

758

636

}

759

637

760

if(quit_now){

761

errno = EINTR;

762

goto mandos_end;

763

}

764

765

638

if(af == AF_INET6){

766

639

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

767

640

} else {

768

641

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

769

642

}

770

643

if(ret < 0){

771

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

772

int e = errno;

773

perror_plus("connect");

774

errno = e;

775

}

776

goto mandos_end;

777

}

778

779

if(quit_now){

780

errno = EINTR;

781

goto mandos_end;

644

perror("connect");

645

return -1;

782

646

}

783

647

784

648

const char *out = mandos_protocol_version;

786

650

while(true){

787

651

size_t out_size = strlen(out);

788

652

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

789

out_size - written));

653

out_size - written));

790

654

if(ret == -1){

791

int e = errno;

792

perror_plus("write");

793

errno = e;

655

perror("write");

656

retval = -1;

794

657

goto mandos_end;

795

658

}

796

659

written += (size_t)ret;

804

667

break;

805

668

}

806

669

}

807

808

if(quit_now){

809

errno = EINTR;

810

goto mandos_end;

811

}

812

670

}

813

671

814

672

if(debug){

815

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

816

}

817

818

if(quit_now){

819

errno = EINTR;

820

goto mandos_end;

821

}

822

823

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

824

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

825

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

826

gnutls_transport_set_ptr(session,

827

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

828

829

if(quit_now){

830

errno = EINTR;

831

goto mandos_end;

832

}

833

834

do {

673

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

674

}

675

676

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

677

678

do{

835

679

ret = gnutls_handshake(session);

836

if(quit_now){

837

errno = EINTR;

838

goto mandos_end;

839

}

840

680

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

841

681

842

682

if(ret != GNUTLS_E_SUCCESS){

843

683

if(debug){

844

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

684

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

845

685

gnutls_perror(ret);

846

686

}

847

errno = EPROTO;

687

retval = -1;

848

688

goto mandos_end;

849

689

}

850

690

851

691

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

852

692

853

693

if(debug){

854

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

855

" %s\n", ip);

694

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

695

ip);

856

696

}

857

697

858

698

while(true){

859

860

if(quit_now){

861

errno = EINTR;

862

goto mandos_end;

863

}

864

865

699

buffer_capacity = incbuffer(&buffer, buffer_length,

866

buffer_capacity);

700

buffer_capacity);

867

701

if(buffer_capacity == 0){

868

int e = errno;

869

perror_plus("incbuffer");

870

errno = e;

871

goto mandos_end;

872

}

873

874

if(quit_now){

875

errno = EINTR;

702

perror("incbuffer");

703

retval = -1;

876

704

goto mandos_end;

877

705

}

878

706

887

715

case GNUTLS_E_AGAIN:

888

716

break;

889

717

case GNUTLS_E_REHANDSHAKE:

890

do {

718

do{

891

719

ret = gnutls_handshake(session);

892

893

if(quit_now){

894

errno = EINTR;

895

goto mandos_end;

896

}

897

720

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

898

721

if(ret < 0){

899

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

900

"***\n");

722

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

901

723

gnutls_perror(ret);

902

errno = EPROTO;

724

retval = -1;

903

725

goto mandos_end;

904

726

}

905

727

break;

906

728

default:

907

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

908

" encrypted session with Mandos server\n");

729

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

730

" encrypted session with Mandos server\n");

731

retval = -1;

909

732

gnutls_bye(session, GNUTLS_SHUT_RDWR);

910

errno = EIO;

911

733

goto mandos_end;

912

734

}

913

735

} else {

916

738

}

917

739

918

740

if(debug){

919

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

920

}

921

922

if(quit_now){

923

errno = EINTR;

924

goto mandos_end;

925

}

926

927

do {

928

ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);

929

if(quit_now){

930

errno = EINTR;

931

goto mandos_end;

932

}

933

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

741

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

742

}

743

744

gnutls_bye(session, GNUTLS_SHUT_RDWR);

934

745

935

746

if(buffer_length > 0){

936

ssize_t decrypted_buffer_size;

937

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

747

decrypted_buffer_size = pgp_packet_decrypt(buffer,

748

buffer_length,

938

749

&decrypted_buffer);

939

750

if(decrypted_buffer_size >= 0){

940

941

751

written = 0;

942

752

while(written < (size_t) decrypted_buffer_size){

943

if(quit_now){

944

errno = EINTR;

945

goto mandos_end;

946

}

947

948

753

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

949

754

(size_t)decrypted_buffer_size - written,

950

755

stdout);

951

756

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

952

int e = errno;

953

757

if(debug){

954

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

955

strerror(errno));

758

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

759

strerror(errno));

956

760

}

957

errno = e;

958

goto mandos_end;

761

retval = -1;

762

break;

959

763

}

960

764

written += (size_t)ret;

961

765

}

962

retval = 0;

766

free(decrypted_buffer);

767

} else {

768

retval = -1;

963

769

}

770

} else {

771

retval = -1;

964

772

}

965

773

966

774

/* Shutdown procedure */

967

775

968

776

mandos_end:

969

{

970

int e = errno;

971

free(decrypted_buffer);

972

free(buffer);

973

if(tcp_sd >= 0){

974

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

975

}

976

if(ret == -1){

977

if(e == 0){

978

e = errno;

979

}

980

perror_plus("close");

981

}

982

gnutls_deinit(session);

983

errno = e;

984

if(quit_now){

985

errno = EINTR;

986

retval = -1;

987

}

777

free(buffer);

778

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

779

if(ret == -1){

780

perror("close");

988

781

}

782

gnutls_deinit(session);

989

783

return retval;

990

784

}

991

785

1003

797

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1004

798

flags,

1005

799

AVAHI_GCC_UNUSED void* userdata){

1006

if(r == NULL){

1007

return;

1008

}

800

assert(r);

1009

801

1010

802

/* Called whenever a service has been resolved successfully or

1011

803

timed out */

1017

809

switch(event){

1018

810

default:

1019

811

case AVAHI_RESOLVER_FAILURE:

1020

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

1021

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

1022

domain,

1023

avahi_strerror(avahi_server_errno(mc.server)));

812

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

813

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

814

avahi_strerror(avahi_server_errno(mc.server)));

1024

815

break;

1025

816

1026

817

case AVAHI_RESOLVER_FOUND:

1028

819

char ip[AVAHI_ADDRESS_STR_MAX];

1029

820

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

1030

821

if(debug){

1031

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

1032

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

1033

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

822

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

823

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

824

ip, (intmax_t)interface, port);

1034

825

}

1035

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

1036

interface,

826

int ret = start_mandos_communication(ip, port, interface,

1037

827

avahi_proto_to_af(proto));

1038

828

if(ret == 0){

1039

avahi_simple_poll_quit(simple_poll);

1040

} else {

1041

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

1042

avahi_proto_to_af(proto))){

1043

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

1044

" list\n", name);

1045

}

829

avahi_simple_poll_quit(mc.simple_poll);

1046

830

}

1047

831

}

1048

832

}

1059

843

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1060

844

flags,

1061

845

AVAHI_GCC_UNUSED void* userdata){

1062

if(b == NULL){

1063

return;

1064

}

846

assert(b);

1065

847

1066

848

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

1067

849

is removed from the LAN */

1068

850

1069

if(quit_now){

1070

return;

1071

}

1072

1073

851

switch(event){

1074

852

default:

1075

853

case AVAHI_BROWSER_FAILURE:

1076

854

1077

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

1078

avahi_strerror(avahi_server_errno(mc.server)));

1079

avahi_simple_poll_quit(simple_poll);

855

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

856

avahi_strerror(avahi_server_errno(mc.server)));

857

avahi_simple_poll_quit(mc.simple_poll);

1080

858

return;

1081

859

1082

860

case AVAHI_BROWSER_NEW:

1088

866

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

1089

867

name, type, domain, protocol, 0,

1090

868

resolve_callback, NULL) == NULL)

1091

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

1092

" %s\n", name,

1093

avahi_strerror(avahi_server_errno(mc.server)));

869

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

870

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

1094

871

break;

1095

872

1096

873

case AVAHI_BROWSER_REMOVE:

1099

876

case AVAHI_BROWSER_ALL_FOR_NOW:

1100

877

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1101

878

if(debug){

1102

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

1103

" searching...\n");

879

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

1104

880

}

1105

881

break;

1106

882

}

1107

883

}

1108

884

1109

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

885

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

1110

886

static void handle_sigterm(int sig){

1111

887

if(quit_now){

1112

888

return;

1114

890

quit_now = 1;

1115

891

signal_received = sig;

1116

892

int old_errno = errno;

1117

/* set main loop to exit */

1118

if(simple_poll != NULL){

1119

avahi_simple_poll_quit(simple_poll);

1120

}

1121

errno = old_errno;

1122

}

1123

1124

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

1125

int ret;

1126

error_t ret_errno;

1127

1128

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

1129

if(s < 0){

1130

ret_errno = errno;

1131

perror_plus("socket");

1132

errno = ret_errno;

1133

return false;

1134

}

1135

strcpy(ifr->ifr_name, ifname);

1136

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1137

if(ret == -1){

1138

if(debug){

1139

ret_errno = errno;

1140

perror_plus("ioctl SIOCGIFFLAGS");

1141

errno = ret_errno;

1142

}

1143

return false;

1144

}

1145

return true;

1146

}

1147

1148

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

1149

1150

/* Reject the loopback device */

1151

if(ifr->ifr_flags & IFF_LOOPBACK){

1152

if(debug){

1153

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

1154

ifname);

1155

}

1156

return false;

1157

}

1158

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

1159

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

1160

if(debug){

1161

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

1162

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

1163

}

1164

return true;

1165

}

1166

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

1167

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

1168

if(debug){

1169

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1170

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

1171

}

1172

return false;

1173

}

1174

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

1175

if(ifr->ifr_flags & IFF_NOARP){

1176

if(debug){

1177

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

1178

ifname);

1179

}

1180

return false;

1181

}

1182

1183

/* Accept this device */

1184

if(debug){

1185

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

1186

}

1187

return true;

1188

}

1189

1190

/*

1191

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

1192

* corresponds to an acceptable network device.

1193

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

1194

*/

1195

int good_interface(const struct dirent *if_entry){

1196

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

1197

return 0;

1198

}

1199

1200

struct ifreq ifr;

1201

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

1202

if(debug){

1203

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

1204

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

1205

}

1206

return 0;

1207

}

1208

1209

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

1210

return 0;

1211

}

1212

return 1;

1213

}

1214

1215

/*

1216

* This function determines if a network interface is up.

1217

*/

1218

bool interface_is_up(const char *interface){

1219

struct ifreq ifr;

1220

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

1221

if(debug){

1222

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

1223

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

1224

}

1225

return false;

1226

}

1227

1228

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

1229

}

1230

1231

/*

1232

* This function determines if a network interface is running

1233

*/

1234

bool interface_is_running(const char *interface){

1235

struct ifreq ifr;

1236

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

1237

if(debug){

1238

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

1239

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

1240

}

1241

return false;

1242

}

1243

1244

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

1245

}

1246

1247

int notdotentries(const struct dirent *direntry){

1248

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

1249

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

1250

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

1251

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

1252

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

1253

return 0;

1254

}

1255

return 1;

1256

}

1257

1258

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

1259

int runnable_hook(const struct dirent *direntry){

1260

int ret;

1261

size_t sret;

1262

struct stat st;

1263

1264

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

1265

/* Empty name? */

1266

return 0;

1267

}

1268

1269

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

1270

"abcdefghijklmnopqrstuvwxyz"

1271

"0123456789"

1272

"_-");

1273

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

1274

/* Contains non-allowed characters */

1275

if(debug){

1276

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

1277

direntry->d_name);

1278

}

1279

return 0;

1280

}

1281

1282

char *fullname = NULL;

1283

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

1284

if(ret < 0){

1285

perror_plus("asprintf");

1286

return 0;

1287

}

1288

1289

ret = stat(fullname, &st);

1290

if(ret == -1){

1291

if(debug){

1292

perror_plus("Could not stat hook");

1293

}

1294

return 0;

1295

}

1296

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

1297

/* Not a regular file */

1298

if(debug){

1299

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

1300

direntry->d_name);

1301

}

1302

return 0;

1303

}

1304

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

1305

/* Not executable */

1306

if(debug){

1307

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

1308

direntry->d_name);

1309

}

1310

return 0;

1311

}

1312

if(debug){

1313

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

1314

direntry->d_name);

1315

}

1316

return 1;

1317

}

1318

1319

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1320

int ret;

1321

struct timespec now;

1322

struct timespec waited_time;

1323

intmax_t block_time;

1324

1325

while(true){

1326

if(mc.current_server == NULL){

1327

if (debug){

1328

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

1329

" No timeout!\n");

1330

}

1331

ret = avahi_simple_poll_iterate(s, -1);

1332

} else {

1333

if (debug){

1334

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

1335

" it, or wait\n");

1336

}

1337

/* the current time */

1338

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1339

if(ret == -1){

1340

perror_plus("clock_gettime");

1341

return -1;

1342

}

1343

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

1344

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

1345

waited_time.tv_sec = (now.tv_sec

1346

- mc.current_server->last_seen.tv_sec);

1347

waited_time.tv_nsec = (now.tv_nsec

1348

- mc.current_server->last_seen.tv_nsec);

1349

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

1350

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

1351

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

1352

block_time = ((retry_interval

1353

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

1354

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

1355

1356

if (debug){

1357

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

1358

block_time);

1359

}

1360

1361

if(block_time <= 0){

1362

ret = start_mandos_communication(mc.current_server->ip,

1363

mc.current_server->port,

1364

mc.current_server->if_index,

1365

mc.current_server->af);

1366

if(ret == 0){

1367

avahi_simple_poll_quit(simple_poll);

1368

return 0;

1369

}

1370

ret = clock_gettime(CLOCK_MONOTONIC,

1371

&mc.current_server->last_seen);

1372

if(ret == -1){

1373

perror_plus("clock_gettime");

1374

return -1;

1375

}

1376

mc.current_server = mc.current_server->next;

1377

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

1378

servers, but don't block */

1379

}

1380

1381

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

1382

}

1383

if(ret != 0){

1384

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

1385

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

1386

}

1387

}

1388

}

1389

}

1390

1391

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

1392

error_t raise_privileges(void){

1393

error_t old_errno = errno;

1394

error_t ret_errno = 0;

1395

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

1396

ret_errno = errno;

1397

perror_plus("seteuid");

1398

}

1399

errno = old_errno;

1400

return ret_errno;

1401

}

1402

1403

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

1404

error_t raise_privileges_permanently(void){

1405

error_t old_errno = errno;

1406

error_t ret_errno = raise_privileges();

1407

if(ret_errno != 0){

1408

errno = old_errno;

1409

return ret_errno;

1410

}

1411

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

1412

ret_errno = errno;

1413

perror_plus("seteuid");

1414

}

1415

errno = old_errno;

1416

return ret_errno;

1417

}

1418

1419

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

1420

error_t lower_privileges(void){

1421

error_t old_errno = errno;

1422

error_t ret_errno = 0;

1423

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

1424

ret_errno = errno;

1425

perror_plus("seteuid");

1426

}

1427

errno = old_errno;

1428

return ret_errno;

1429

}

1430

1431

/* Lower privileges permanently */

1432

error_t lower_privileges_permanently(void){

1433

error_t old_errno = errno;

1434

error_t ret_errno = 0;

1435

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

1436

ret_errno = errno;

1437

perror_plus("setuid");

1438

}

1439

errno = old_errno;

1440

return ret_errno;

1441

}

1442

1443

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

1444

const float delay){

1445

struct dirent **direntries;

1446

struct dirent *direntry;

1447

int ret;

1448

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

1449

alphasort);

1450

if(numhooks == -1){

1451

if(errno == ENOENT){

1452

if(debug){

1453

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

1454

" found\n", hookdir);

1455

}

1456

} else {

1457

perror_plus("scandir");

1458

}

1459

} else {

1460

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

1461

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

1462

direntry = direntries[i];

1463

char *fullname = NULL;

1464

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

1465

if(ret < 0){

1466

perror_plus("asprintf");

1467

continue;

1468

}

1469

if(debug){

1470

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

1471

direntry->d_name);

1472

}

1473

pid_t hook_pid = fork();

1474

if(hook_pid == 0){

1475

/* Child */

1476

/* Raise privileges */

1477

raise_privileges_permanently();

1478

/* Set group */

1479

errno = 0;

1480

ret = setgid(0);

1481

if(ret == -1){

1482

perror_plus("setgid");

1483

}

1484

/* Reset supplementary groups */

1485

errno = 0;

1486

ret = setgroups(0, NULL);

1487

if(ret == -1){

1488

perror_plus("setgroups");

1489

}

1490

dup2(devnull, STDIN_FILENO);

1491

close(devnull);

1492

dup2(STDERR_FILENO, STDOUT_FILENO);

1493

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

1494

if(ret == -1){

1495

perror_plus("setenv");

1496

_exit(EX_OSERR);

1497

}

1498

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

1499

if(ret == -1){

1500

perror_plus("setenv");

1501

_exit(EX_OSERR);

1502

}

1503

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

1504

if(ret == -1){

1505

perror_plus("setenv");

1506

_exit(EX_OSERR);

1507

}

1508

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

1509

if(ret == -1){

1510

perror_plus("setenv");

1511

_exit(EX_OSERR);

1512

}

1513

char *delaystring;

1514

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

1515

if(ret == -1){

1516

perror_plus("asprintf");

1517

_exit(EX_OSERR);

1518

}

1519

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

1520

if(ret == -1){

1521

free(delaystring);

1522

perror_plus("setenv");

1523

_exit(EX_OSERR);

1524

}

1525

free(delaystring);

1526

if(connect_to != NULL){

1527

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

1528

if(ret == -1){

1529

perror_plus("setenv");

1530

_exit(EX_OSERR);

1531

}

1532

}

1533

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

1534

perror_plus("execl");

1535

_exit(EXIT_FAILURE);

1536

}

1537

} else {

1538

int status;

1539

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

1540

perror_plus("waitpid");

1541

free(fullname);

1542

continue;

1543

}

1544

if(WIFEXITED(status)){

1545

if(WEXITSTATUS(status) != 0){

1546

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

1547

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

1548

WEXITSTATUS(status));

1549

free(fullname);

1550

continue;

1551

}

1552

} else if(WIFSIGNALED(status)){

1553

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

1554

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

1555

WTERMSIG(status));

1556

free(fullname);

1557

continue;

1558

} else {

1559

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

1560

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

1561

free(fullname);

1562

continue;

1563

}

1564

}

1565

free(fullname);

1566

if(debug){

1567

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

1568

direntry->d_name);

1569

}

1570

}

1571

close(devnull);

1572

}

1573

return true;

1574

}

1575

1576

error_t bring_up_interface(const char *const interface,

1577

const float delay){

1578

int sd = -1;

1579

error_t old_errno = errno;

1580

error_t ret_errno = 0;

1581

int ret, ret_setflags;

1582

struct ifreq network;

1583

unsigned int if_index = if_nametoindex(interface);

1584

if(if_index == 0){

1585

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

1586

errno = old_errno;

1587

return ENXIO;

1588

}

1589

1590

if(quit_now){

1591

errno = old_errno;

1592

return EINTR;

1593

}

1594

1595

if(not interface_is_up(interface)){

1596

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

1597

ret_errno = errno;

1598

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

1599

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

1600

return ret_errno;

1601

}

1602

network.ifr_flags |= IFF_UP;

1603

1604

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1605

if(sd < 0){

1606

ret_errno = errno;

1607

perror_plus("socket");

1608

errno = old_errno;

1609

return ret_errno;

1610

}

1611

1612

if(quit_now){

1613

close(sd);

1614

errno = old_errno;

1615

return EINTR;

1616

}

1617

1618

if(debug){

1619

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

1620

interface);

1621

}

1622

1623

/* Raise priviliges */

1624

raise_privileges();

1625

1626

#ifdef __linux__

1627

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1628

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

1629

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

1630

bool restore_loglevel = true;

1631

if(ret_linux == -1){

1632

restore_loglevel = false;

1633

perror_plus("klogctl");

1634

}

1635

#endif /* __linux__ */

1636

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

1637

ret_errno = errno;

1638

#ifdef __linux__

1639

if(restore_loglevel){

1640

ret_linux = klogctl(7, NULL, 0);

1641

if(ret_linux == -1){

1642

perror_plus("klogctl");

1643

}

1644

}

1645

#endif /* __linux__ */

1646

1647

/* Lower privileges */

1648

lower_privileges();

1649

1650

/* Close the socket */

1651

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

1652

if(ret == -1){

1653

perror_plus("close");

1654

}

1655

1656

if(ret_setflags == -1){

1657

errno = ret_errno;

1658

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1659

errno = old_errno;

1660

return ret_errno;

1661

}

1662

} else if(debug){

1663

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

1664

interface);

1665

}

1666

1667

/* Sleep checking until interface is running.

1668

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

1669

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

1670

if(interface_is_running(interface)){

1671

break;

1672

}

1673

struct timespec sleeptime = { .tv_nsec = 250000000 };

1674

ret = nanosleep(&sleeptime, NULL);

1675

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

1676

perror_plus("nanosleep");

1677

}

1678

}

1679

1680

errno = old_errno;

1681

return 0;

1682

}

1683

1684

error_t take_down_interface(const char *const interface){

1685

int sd = -1;

1686

error_t old_errno = errno;

1687

error_t ret_errno = 0;

1688

int ret, ret_setflags;

1689

struct ifreq network;

1690

unsigned int if_index = if_nametoindex(interface);

1691

if(if_index == 0){

1692

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

1693

errno = old_errno;

1694

return ENXIO;

1695

}

1696

if(interface_is_up(interface)){

1697

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

1698

ret_errno = errno;

1699

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

1700

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

1701

return ret_errno;

1702

}

1703

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

1704

1705

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1706

if(sd < 0){

1707

ret_errno = errno;

1708

perror_plus("socket");

1709

errno = old_errno;

1710

return ret_errno;

1711

}

1712

1713

if(debug){

1714

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

1715

interface);

1716

}

1717

1718

/* Raise priviliges */

1719

raise_privileges();

1720

1721

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

1722

ret_errno = errno;

1723

1724

/* Lower privileges */

1725

lower_privileges();

1726

1727

/* Close the socket */

1728

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

1729

if(ret == -1){

1730

perror_plus("close");

1731

}

1732

1733

if(ret_setflags == -1){

1734

errno = ret_errno;

1735

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1736

errno = old_errno;

1737

return ret_errno;

1738

}

1739

} else if(debug){

1740

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

1741

interface);

1742

}

1743

1744

errno = old_errno;

1745

return 0;

893

if(mc.simple_poll != NULL){

894

avahi_simple_poll_quit(mc.simple_poll);

895

}

896

errno = old_errno;

1746

897

}

1747

898

1748

899

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

1749

900

AvahiSServiceBrowser *sb = NULL;

1750

error_t ret_errno;

901

int error;

1751

902

int ret;

1752

903

intmax_t tmpmax;

1753

904

char *tmp;

1754

905

int exitcode = EXIT_SUCCESS;

1755

char *interfaces = NULL;

1756

size_t interfaces_size = 0;

1757

char *interfaces_to_take_down = NULL;

1758

size_t interfaces_to_take_down_size = 0;

906

const char *interface = "eth0";

907

struct ifreq network;

908

int sd = -1;

909

bool take_down_interface = false;

910

uid_t uid;

911

gid_t gid;

912

char *connect_to = NULL;

1759

913

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

1760

914

bool tempdir_created = false;

1761

915

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1762

916

const char *seckey = PATHDIR "/" SECKEY;

1763

917

const char *pubkey = PATHDIR "/" PUBKEY;

1764

char *interfaces_hooks = NULL;

1765

size_t interfaces_hooks_size = 0;

1766

918

1767

919

bool gnutls_initialized = false;

1768

920

bool gpgme_initialized = false;

1769

921

float delay = 2.5f;

1770

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

1771

retrying the same server again */

1772

922

1773

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

923

struct sigaction old_sigterm_action;

1774

924

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1775

925

1776

uid = getuid();

1777

gid = getgid();

1778

1779

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

1780

errno = 0;

1781

ret = setgid(gid);

1782

if(ret == -1){

1783

perror_plus("setgid");

1784

}

1785

1786

/* Lower user privileges (temporarily) */

1787

errno = 0;

1788

ret = seteuid(uid);

1789

if(ret == -1){

1790

perror_plus("seteuid");

1791

}

1792

1793

if(quit_now){

1794

goto end;

1795

}

1796

1797

926

{

1798

927

struct argp_option options[] = {

1799

928

{ .name = "debug", .key = 128,

1828

957

.arg = "SECONDS",

1829

958

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

1830

959

.group = 2 },

1831

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

1832

.arg = "SECONDS",

1833

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

1834

.group = 2 },

1835

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

1836

.arg = "DIR",

1837

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

1838

.group = 2 },

1839

/*

1840

* These reproduce what we would get without ARGP_NO_HELP

1841

*/

1842

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

1843

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

1844

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

1845

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

1846

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

1847

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

1848

960

{ .name = NULL }

1849

961

};

1850

962

1851

963

error_t parse_opt(int key, char *arg,

1852

964

struct argp_state *state){

1853

errno = 0;

1854

965

switch(key){

1855

966

case 128: /* --debug */

1856

967

debug = true;

1859

970

connect_to = arg;

1860

971

break;

1861

972

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

1862

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

1863

(int)',');

1864

if(ret_errno != 0){

1865

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

1866

}

973

interface = arg;

1867

974

break;

1868

975

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

1869

976

seckey = arg;

1876

983

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

1877

984

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

1878

985

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

1879

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

986

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

987

exit(EXIT_FAILURE);

1880

988

}

1881

989

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

1882

990

break;

1887

995

errno = 0;

1888

996

delay = strtof(arg, &tmp);

1889

997

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

1890

argp_error(state, "Bad delay");

1891

}

1892

case 132: /* --retry */

1893

errno = 0;

1894

retry_interval = strtod(arg, &tmp);

1895

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

1896

or (retry_interval * 1000) > INT_MAX

1897

or retry_interval < 0){

1898

argp_error(state, "Bad retry interval");

1899

}

1900

break;

1901

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

1902

hookdir = arg;

1903

break;

1904

/*

1905

* These reproduce what we would get without ARGP_NO_HELP

1906

*/

1907

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

1908

argp_state_help(state, state->out_stream,

1909

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

1910

& ~(unsigned int)ARGP_HELP_EXIT_OK);

1911

case -3: /* --usage */

1912

argp_state_help(state, state->out_stream,

1913

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1914

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

1915

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

1916

exit(argp_err_exit_status);

998

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

999

exit(EXIT_FAILURE);

1000

}

1001

break;

1002

case ARGP_KEY_ARG:

1003

argp_usage(state);

1004

case ARGP_KEY_END:

1917

1005

break;

1918

1006

default:

1919

1007

return ARGP_ERR_UNKNOWN;

1920

1008

}

1921

return errno;

1009

return 0;

1922

1010

}

1923

1011

1924

1012

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

1925

1013

.args_doc = "",

1926

1014

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

1927

1015

" passwords from a Mandos server" };

1928

ret = argp_parse(&argp, argc, argv,

1929

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1930

switch(ret){

1931

case 0:

1932

break;

1933

case ENOMEM:

1934

default:

1935

errno = ret;

1936

perror_plus("argp_parse");

1937

exitcode = EX_OSERR;

1938

goto end;

1939

case EINVAL:

1940

exitcode = EX_USAGE;

1941

goto end;

1942

}

1943

}

1944

1945

{

1946

/* Work around Debian bug #633582:

1947

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

1948

1949

/* Re-raise priviliges */

1950

if(raise_privileges() == 0){

1951

struct stat st;

1952

1953

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

1954

int seckey_fd = open(seckey, O_RDONLY);

1955

if(seckey_fd == -1){

1956

perror_plus("open");

1957

} else {

1958

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

1959

if(ret == -1){

1960

perror_plus("fstat");

1961

} else {

1962

if(S_ISREG(st.st_mode)

1963

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

1964

ret = fchown(seckey_fd, uid, gid);

1965

if(ret == -1){

1966

perror_plus("fchown");

1967

}

1968

}

1969

}

1970

TEMP_FAILURE_RETRY(close(seckey_fd));

1971

}

1972

}

1973

1974

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

1975

int pubkey_fd = open(pubkey, O_RDONLY);

1976

if(pubkey_fd == -1){

1977

perror_plus("open");

1978

} else {

1979

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

1980

if(ret == -1){

1981

perror_plus("fstat");

1982

} else {

1983

if(S_ISREG(st.st_mode)

1984

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

1985

ret = fchown(pubkey_fd, uid, gid);

1986

if(ret == -1){

1987

perror_plus("fchown");

1988

}

1989

}

1990

}

1991

TEMP_FAILURE_RETRY(close(pubkey_fd));

1992

}

1993

}

1994

1995

/* Lower privileges */

1996

errno = 0;

1997

ret = seteuid(uid);

1998

if(ret == -1){

1999

perror_plus("seteuid");

2000

}

2001

}

2002

}

2003

2004

/* Remove empty interface names */

2005

{

2006

char *interface = NULL;

2007

while((interface = argz_next(interfaces, interfaces_size,

2008

interface))){

2009

if(if_nametoindex(interface) == 0){

2010

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

2011

fprintf_plus(stderr, "Not using nonexisting interface"

2012

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

2013

}

2014

argz_delete(&interfaces, &interfaces_size, interface);

2015

interface = NULL;

2016

}

2017

}

2018

}

2019

2020

/* Run network hooks */

2021

{

2022

2023

if(interfaces != NULL){

2024

interfaces_hooks = malloc(interfaces_size);

2025

if(interfaces_hooks == NULL){

2026

perror_plus("malloc");

2027

goto end;

2028

}

2029

memcpy(interfaces_hooks, interfaces, interfaces_size);

2030

interfaces_hooks_size = interfaces_size;

2031

argz_stringify(interfaces_hooks, interfaces_hooks_size,

2032

(int)',');

2033

}

2034

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

2035

interfaces_hooks : "", delay)){

1016

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

1017

if(ret == ARGP_ERR_UNKNOWN){

1018

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

1019

exitcode = EXIT_FAILURE;

2036

1020

goto end;

2037

1021

}

2038

1022

}

2045

1029

from the signal handler */

2046

1030

/* Initialize the pseudo-RNG for Avahi */

2047

1031

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

2048

simple_poll = avahi_simple_poll_new();

2049

if(simple_poll == NULL){

2050

fprintf_plus(stderr,

2051

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

2052

exitcode = EX_UNAVAILABLE;

1032

mc.simple_poll = avahi_simple_poll_new();

1033

if(mc.simple_poll == NULL){

1034

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

1035

exitcode = EXIT_FAILURE;

2053

1036

goto end;

2054

1037

}

2055

1038

2056

1039

sigemptyset(&sigterm_action.sa_mask);

2057

1040

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

2058

1041

if(ret == -1){

2059

perror_plus("sigaddset");

2060

exitcode = EX_OSERR;

1042

perror("sigaddset");

1043

exitcode = EXIT_FAILURE;

2061

1044

goto end;

2062

1045

}

2063

1046

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

2064

1047

if(ret == -1){

2065

perror_plus("sigaddset");

2066

exitcode = EX_OSERR;

1048

perror("sigaddset");

1049

exitcode = EXIT_FAILURE;

2067

1050

goto end;

2068

1051

}

2069

1052

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

2070

1053

if(ret == -1){

2071

perror_plus("sigaddset");

2072

exitcode = EX_OSERR;

2073

goto end;

2074

}

2075

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

2076

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

2077

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

2078

*/

2079

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

2080

if(ret == -1){

2081

perror_plus("sigaction");

2082

return EX_OSERR;

2083

}

2084

if(old_sigterm_action.sa_handler != SIG_IGN){

2085

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

2086

if(ret == -1){

2087

perror_plus("sigaction");

2088

exitcode = EX_OSERR;

2089

goto end;

2090

}

2091

}

2092

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

2093

if(ret == -1){

2094

perror_plus("sigaction");

2095

return EX_OSERR;

2096

}

2097

if(old_sigterm_action.sa_handler != SIG_IGN){

2098

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

2099

if(ret == -1){

2100

perror_plus("sigaction");

2101

exitcode = EX_OSERR;

2102

goto end;

2103

}

2104

}

2105

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

2106

if(ret == -1){

2107

perror_plus("sigaction");

2108

return EX_OSERR;

2109

}

2110

if(old_sigterm_action.sa_handler != SIG_IGN){

2111

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

2112

if(ret == -1){

2113

perror_plus("sigaction");

2114

exitcode = EX_OSERR;

2115

goto end;

2116

}

2117

}

2118

2119

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

2120

if(interfaces == NULL){

2121

struct dirent **direntries;

2122

/* Look for any good interfaces */

2123

ret = scandir(sys_class_net, &direntries, good_interface,

2124

alphasort);

2125

if(ret >= 1){

2126

/* Add all found interfaces to interfaces list */

2127

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

2128

ret_errno = argz_add(&interfaces, &interfaces_size,

2129

direntries[i]->d_name);

2130

if(ret_errno != 0){

2131

perror_plus("argz_add");

2132

continue;

2133

}

2134

if(debug){

2135

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

2136

direntries[i]->d_name);

2137

}

2138

}

2139

free(direntries);

2140

} else {

2141

free(direntries);

2142

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

2143

exitcode = EXIT_FAILURE;

2144

goto end;

2145

}

2146

}

2147

2148

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

2149

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

2150

if(debug){

2151

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

2152

interfaces);

2153

}

2154

if_index = (AvahiIfIndex)if_nametoindex(interfaces);

2155

}

2156

2157

/* Bring up interfaces which are down */

2158

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

2159

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

2160

char *interface = NULL;

2161

while((interface = argz_next(interfaces, interfaces_size,

2162

interface))){

2163

bool interface_was_up = interface_is_up(interface);

2164

ret = bring_up_interface(interface, delay);

2165

if(not interface_was_up){

2166

if(ret != 0){

2167

errno = ret;

2168

perror_plus("Failed to bring up interface");

2169

} else {

2170

ret_errno = argz_add(&interfaces_to_take_down,

2171

&interfaces_to_take_down_size,

2172

interface);

2173

}

2174

}

2175

}

2176

free(interfaces);

2177

interfaces = NULL;

2178

interfaces_size = 0;

2179

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

2180

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

2181

}

1054

perror("sigaddset");

1055

exitcode = EXIT_FAILURE;

1056

goto end;

1057

}

1058

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

1059

if(ret == -1){

1060

perror("sigaction");

1061

exitcode = EXIT_FAILURE;

1062

goto end;

1063

}

1064

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

1065

if(ret == -1){

1066

perror("sigaction");

1067

exitcode = EXIT_FAILURE;

1068

goto end;

1069

}

1070

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

1071

if(ret == -1){

1072

perror("sigaction");

1073

exitcode = EXIT_FAILURE;

1074

goto end;

1075

}

1076

1077

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

1078

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

1079

if_index = (AvahiIfIndex) if_nametoindex(interface);

1080

if(if_index == 0){

1081

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

1082

exitcode = EXIT_FAILURE;

1083

goto end;

1084

}

1085

1086

if(quit_now){

1087

goto end;

1088

}

1089

1090

#ifdef __linux__

1091

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1092

messages to mess up the prompt */

1093

ret = klogctl(8, NULL, 5);

1094

bool restore_loglevel = true;

1095

if(ret == -1){

1096

restore_loglevel = false;

1097

perror("klogctl");

1098

}

1099

#endif /* __linux__ */

1100

1101

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1102

if(sd < 0){

1103

perror("socket");

1104

exitcode = EXIT_FAILURE;

1105

#ifdef __linux__

1106

if(restore_loglevel){

1107

ret = klogctl(7, NULL, 0);

1108

if(ret == -1){

1109

perror("klogctl");

1110

}

1111

}

1112

#endif /* __linux__ */

1113

goto end;

1114

}

1115

strcpy(network.ifr_name, interface);

1116

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

1117

if(ret == -1){

1118

perror("ioctl SIOCGIFFLAGS");

1119

#ifdef __linux__

1120

if(restore_loglevel){

1121

ret = klogctl(7, NULL, 0);

1122

if(ret == -1){

1123

perror("klogctl");

1124

}

1125

}

1126

#endif /* __linux__ */

1127

exitcode = EXIT_FAILURE;

1128

goto end;

1129

}

1130

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

1131

network.ifr_flags |= IFF_UP;

1132

take_down_interface = true;

1133

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

1134

if(ret == -1){

1135

take_down_interface = false;

1136

perror("ioctl SIOCSIFFLAGS");

1137

exitcode = EXIT_FAILURE;

1138

#ifdef __linux__

1139

if(restore_loglevel){

1140

ret = klogctl(7, NULL, 0);

1141

if(ret == -1){

1142

perror("klogctl");

1143

}

1144

}

1145

#endif /* __linux__ */

1146

goto end;

1147

}

1148

}

1149

/* sleep checking until interface is running */

1150

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

1151

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

1152

if(ret == -1){

1153

perror("ioctl SIOCGIFFLAGS");

1154

} else if(network.ifr_flags & IFF_RUNNING){

1155

break;

1156

}

1157

struct timespec sleeptime = { .tv_nsec = 250000000 };

1158

ret = nanosleep(&sleeptime, NULL);

1159

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

1160

perror("nanosleep");

1161

}

1162

}

1163

if(not take_down_interface){

1164

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

1165

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

1166

if(ret == -1){

1167

perror("close");

1168

}

1169

}

1170

#ifdef __linux__

1171

if(restore_loglevel){

1172

/* Restores kernel loglevel to default */

1173

ret = klogctl(7, NULL, 0);

1174

if(ret == -1){

1175

perror("klogctl");

1176

}

1177

}

1178

#endif /* __linux__ */

1179

}

1180

1181

if(quit_now){

1182

goto end;

1183

}

1184

1185

uid = getuid();

1186

gid = getgid();

1187

1188

errno = 0;

1189

setgid(gid);

1190

if(ret == -1){

1191

perror("setgid");

1192

}

1193

1194

ret = setuid(uid);

1195

if(ret == -1){

1196

perror("setuid");

2182

1197

}

2183

1198

2184

1199

if(quit_now){

2187

1202

2188

1203

ret = init_gnutls_global(pubkey, seckey);

2189

1204

if(ret == -1){

2190

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

2191

exitcode = EX_UNAVAILABLE;

1205

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

1206

exitcode = EXIT_FAILURE;

2192

1207

goto end;

2193

1208

} else {

2194

1209

gnutls_initialized = true;

2198

1213

goto end;

2199

1214

}

2200

1215

1216

tempdir_created = true;

2201

1217

if(mkdtemp(tempdir) == NULL){

2202

perror_plus("mkdtemp");

1218

tempdir_created = false;

1219

perror("mkdtemp");

2203

1220

goto end;

2204

1221

}

2205

tempdir_created = true;

2206

1222

2207

1223

if(quit_now){

2208

1224

goto end;

2209

1225

}

2210

1226

2211

1227

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

2212

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

2213

exitcode = EX_UNAVAILABLE;

1228

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

1229

exitcode = EXIT_FAILURE;

2214

1230

goto end;

2215

1231

} else {

2216

1232

gpgme_initialized = true;

2224

1240

/* Connect directly, do not use Zeroconf */

2225

1241

/* (Mainly meant for debugging) */

2226

1242

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

2227

2228

1243

if(address == NULL){

2229

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

2230

exitcode = EX_USAGE;

1244

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

1245

exitcode = EXIT_FAILURE;

2231

1246

goto end;

2232

1247

}

2233

1248

2235

1250

goto end;

2236

1251

}

2237

1252

2238

in_port_t port;

1253

uint16_t port;

2239

1254

errno = 0;

2240

1255

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

2241

1256

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

2242

or tmpmax != (in_port_t)tmpmax){

2243

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

2244

exitcode = EX_USAGE;

1257

or tmpmax != (uint16_t)tmpmax){

1258

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

1259

exitcode = EXIT_FAILURE;

2245

1260

goto end;

2246

1261

}

2247

1262

2249

1264

goto end;

2250

1265

}

2251

1266

2252

port = (in_port_t)tmpmax;

1267

port = (uint16_t)tmpmax;

2253

1268

*address = '\0';

1269

address = connect_to;

2254

1270

/* Colon in address indicates IPv6 */

2255

1271

int af;

2256

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

1272

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

2257

1273

af = AF_INET6;

2258

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

2259

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

2260

{

2261

connect_to++;

2262

address[-1] = '\0';

2263

}

2264

1274

} else {

2265

1275

af = AF_INET;

2266

1276

}

2267

address = connect_to;

2268

1277

2269

1278

if(quit_now){

2270

1279

goto end;

2271

1280

}

2272

1281

2273

while(not quit_now){

2274

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

2275

if(quit_now or ret == 0){

2276

break;

2277

}

2278

if(debug){

2279

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

2280

(int)retry_interval);

2281

}

2282

sleep((int)retry_interval);

2283

}

2284

2285

if (not quit_now){

1282

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

1283

if(ret < 0){

1284

exitcode = EXIT_FAILURE;

1285

} else {

2286

1286

exitcode = EXIT_SUCCESS;

2287

1287

}

2288

2289

1288

goto end;

2290

1289

}

2291

1290

2303

1302

config.publish_domain = 0;

2304

1303

2305

1304

/* Allocate a new server */

2306

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2307

&config, NULL, NULL, &ret_errno);

1305

mc.server = avahi_server_new(avahi_simple_poll_get

1306

(mc.simple_poll), &config, NULL,

1307

NULL, &error);

2308

1308

2309

1309

/* Free the Avahi configuration data */

2310

1310

avahi_server_config_free(&config);

2312

1312

2313

1313

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

2314

1314

if(mc.server == NULL){

2315

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

2316

avahi_strerror(ret_errno));

2317

exitcode = EX_UNAVAILABLE;

1315

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

1316

avahi_strerror(error));

1317

exitcode = EXIT_FAILURE;

2318

1318

goto end;

2319

1319

}

2320

1320

2327

1327

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2328

1328

NULL, 0, browse_callback, NULL);

2329

1329

if(sb == NULL){

2330

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

2331

avahi_strerror(avahi_server_errno(mc.server)));

2332

exitcode = EX_UNAVAILABLE;

1330

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

1331

avahi_strerror(avahi_server_errno(mc.server)));

1332

exitcode = EXIT_FAILURE;

2333

1333

goto end;

2334

1334

}

2335

1335

2340

1340

/* Run the main loop */

2341

1341

2342

1342

if(debug){

2343

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

2344

}

2345

2346

ret = avahi_loop_with_timeout(simple_poll,

2347

(int)(retry_interval * 1000));

2348

if(debug){

2349

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

2350

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

2351

}

1343

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

1344

}

1345

1346

avahi_simple_poll_loop(mc.simple_poll);

2352

1347

2353

1348

end:

2354

1349

2355

1350

if(debug){

2356

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

1351

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

2357

1352

}

2358

1353

2359

1354

/* Cleanup things */

2363

1358

if(mc.server != NULL)

2364

1359

avahi_server_free(mc.server);

2365

1360

2366

if(simple_poll != NULL)

2367

avahi_simple_poll_free(simple_poll);

1361

if(mc.simple_poll != NULL)

1362

avahi_simple_poll_free(mc.simple_poll);

2368

1363

2369

1364

if(gnutls_initialized){

2370

1365

gnutls_certificate_free_credentials(mc.cred);

2376

1371

gpgme_release(mc.ctx);

2377

1372

}

2378

1373

2379

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

2380

has seen */

2381

if(mc.current_server != NULL){

2382

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

2383

while(mc.current_server != NULL){

2384

server *next = mc.current_server->next;

2385

free(mc.current_server);

2386

mc.current_server = next;

2387

}

2388

}

2389

2390

/* Re-raise priviliges */

2391

{

2392

raise_privileges();

2393

2394

/* Run network hooks */

2395

run_network_hooks("stop", interfaces_hooks != NULL ?

2396

interfaces_hooks : "", delay);

2397

2398

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

2399

{

2400

char *interface = NULL;

2401

while((interface=argz_next(interfaces_to_take_down,

2402

interfaces_to_take_down_size,

2403

interface))){

2404

ret_errno = take_down_interface(interface);

2405

if(ret_errno != 0){

2406

errno = ret_errno;

2407

perror_plus("Failed to take down interface");

2408

}

2409

}

2410

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

2411

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

2412

" down\n");

2413

}

2414

}

2415

2416

lower_privileges_permanently();

2417

}

2418

2419

free(interfaces_to_take_down);

2420

free(interfaces_hooks);

2421

2422

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

1374

/* Take down the network interface */

1375

if(take_down_interface){

1376

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

1377

if(ret == -1){

1378

perror("ioctl SIOCGIFFLAGS");

1379

} else if(network.ifr_flags & IFF_UP) {

1380

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

1381

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

1382

if(ret == -1){

1383

perror("ioctl SIOCSIFFLAGS");

1384

}

1385

}

1386

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

1387

if(ret == -1){

1388

perror("close");

1389

}

1390

}

1391

1392

/* Removes the temp directory used by GPGME */

2423

1393

if(tempdir_created){

2424

struct dirent **direntries = NULL;

2425

struct dirent *direntry = NULL;

2426

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

2427

alphasort);

2428

if (numentries > 0){

2429

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

2430

direntry = direntries[i];

1394

DIR *d;

1395

struct dirent *direntry;

1396

d = opendir(tempdir);

1397

if(d == NULL){

1398

if(errno != ENOENT){

1399

perror("opendir");

1400

}

1401

} else {

1402

while(true){

1403

direntry = readdir(d);

1404

if(direntry == NULL){

1405

break;

1406

}

1407

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

1408

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

1409

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

1410

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

1411

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

1412

continue;

1413

}

2431

1414

char *fullname = NULL;

2432

1415

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

2433

1416

direntry->d_name);

2434

1417

if(ret < 0){

2435

perror_plus("asprintf");

1418

perror("asprintf");

2436

1419

continue;

2437

1420

}

2438

1421

ret = remove(fullname);

2439

1422

if(ret == -1){

2440

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

2441

strerror(errno));

1423

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

1424

strerror(errno));

2442

1425

}

2443

1426

free(fullname);

2444

1427

}

2445

}

2446

2447

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

2448

free(direntries);

2449

if (numentries == -1){

2450

perror_plus("scandir");

1428

closedir(d);

2451

1429

}

2452

1430

ret = rmdir(tempdir);

2453

1431

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

2454

perror_plus("rmdir");

1432

perror("rmdir");

2455

1433

}

2456

1434

}

2457

1435

2458

1436

if(quit_now){

2459

sigemptyset(&old_sigterm_action.sa_mask);

2460

old_sigterm_action.sa_handler = SIG_DFL;

2461

ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,

2462

&old_sigterm_action,

2463

NULL));

1437

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

2464

1438

if(ret == -1){

2465

perror_plus("sigaction");

2466

}

2467

do {

2468

ret = raise(signal_received);

2469

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

2470

if(ret != 0){

2471

perror_plus("raise");

2472

abort();

2473

}

2474

TEMP_FAILURE_RETRY(pause());

1439

perror("sigaction");

1440

}

1441

raise(signal_received);

2475

1442

}

2476

1443

2477

1444

return exitcode;