/mandos/release : revision 237.7.211

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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@fukt.bsnet.se>.

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

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*/

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

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

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stdout, ferror(), remove() */

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

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

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

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

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strtof(), abort() */

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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() */

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

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

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inet_pton(), connect() */

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

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*/

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

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strtoimax() */

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

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

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

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program_invocation_short_name */

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

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

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SIOCSIFFLAGS, if_indextoname(),

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*/

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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() */

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

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

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

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

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

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argp_state, struct argp,

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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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114

init_gnutls_session(),

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115

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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131

#define PUBKEY "pubkey.txt"

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

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133

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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@fukt.bsnet.se>";

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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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139

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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/* 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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159

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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char *interfaces;

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size_t interfaces_size;

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} mandos_context;

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167

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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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/* global so signal handler can reach it*/

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AvahiSimplePoll *simple_poll;

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170

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sig_atomic_t quit_now = 0;

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172

int signal_received = 0;

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/* Function to use when printing errors */

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void perror_plus(const char *print_text){

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int e = errno;

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

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program_invocation_short_name);

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errno = e;

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perror(print_text);

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}

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

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

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va_list ap;

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va_start (ap, format);

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188

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

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program_invocation_short_name));

190

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

191

}

192

152

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/*

153

194

* 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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* "buffer_length" is how much is already used.

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197

*/

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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){

159

200

if(buffer_length + BUFFER_SIZE > buffer_capacity){

160

201

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

161

202

if(buffer == NULL){

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207

return buffer_capacity;

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}

168

209

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

211

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

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int af, server **current_server){

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int ret;

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

215

if(new_server == NULL){

216

perror_plus("malloc");

217

return false;

218

}

219

*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 };

223

if(new_server->ip == NULL){

224

perror_plus("strdup");

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return false;

226

}

227

/* Special case of first server */

228

if(*current_server == NULL){

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new_server->next = new_server;

230

new_server->prev = new_server;

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*current_server = new_server;

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

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} else {

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new_server->next = *current_server;

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

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new_server->prev->next = new_server;

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(*current_server)->prev = new_server;

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}

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

240

if(ret == -1){

241

perror_plus("clock_gettime");

242

return false;

243

}

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return true;

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}

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169

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/*

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248

* Initialize GPGME.

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249

*/

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

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const char *tempdir, mandos_context *mc){

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252

gpgme_error_t rc;

175

253

gpgme_engine_info_t engine_info;

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254

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178

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/*

179

256

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

180

257

*/

185

262

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

187

264

if(fd == -1){

188

perror("open");

265

perror_plus("open");

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266

return false;

190

267

}

191

268

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rc = gpgme_data_new_from_fd(&pgp_data, fd);

193

270

if(rc != GPG_ERR_NO_ERROR){

194

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

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gpgme_strsource(rc), gpgme_strerror(rc));

271

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

272

gpgme_strsource(rc), gpgme_strerror(rc));

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273

return false;

197

274

}

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275

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rc = gpgme_op_import(mc.ctx, pgp_data);

276

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

200

277

if(rc != GPG_ERR_NO_ERROR){

201

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

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gpgme_strsource(rc), gpgme_strerror(rc));

278

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

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281

}

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

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284

if(ret == -1){

208

perror("close");

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perror_plus("close");

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286

}

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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(stderr, "Initializing GPGME\n");

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

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}

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/* Init GPGME */

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gpgme_check_version(NULL);

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rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

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if(rc != GPG_ERR_NO_ERROR){

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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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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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return false;

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302

}

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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 */

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rc = gpgme_get_engine_info(&engine_info);

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if(rc != GPG_ERR_NO_ERROR){

230

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

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gpgme_strsource(rc), gpgme_strerror(rc));

307

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

233

310

}

234

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while(engine_info != NULL){

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317

engine_info = engine_info->next;

241

318

}

242

319

if(engine_info == NULL){

243

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

320

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

321

tempdir);

244

322

return false;

245

323

}

246

324

247

325

/* Create new GPGME "context" */

248

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

326

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

249

327

if(rc != GPG_ERR_NO_ERROR){

250

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

251

gpgme_strsource(rc), gpgme_strerror(rc));

328

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

329

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

330

gpgme_strerror(rc));

252

331

return false;

253

332

}

254

333

265

344

*/

266

345

static ssize_t pgp_packet_decrypt(const char *cryptotext,

267

346

size_t crypto_size,

268

char **plaintext){

347

char **plaintext,

348

mandos_context *mc){

269

349

gpgme_data_t dh_crypto, dh_plain;

270

350

gpgme_error_t rc;

271

351

ssize_t ret;

273

353

ssize_t plaintext_length = 0;

274

354

275

355

if(debug){

276

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

356

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

277

357

}

278

358

279

359

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

280

360

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

281

361

0);

282

362

if(rc != GPG_ERR_NO_ERROR){

283

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

284

gpgme_strsource(rc), gpgme_strerror(rc));

363

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

364

gpgme_strsource(rc), gpgme_strerror(rc));

285

365

return -1;

286

366

}

287

367

288

368

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

289

369

rc = gpgme_data_new(&dh_plain);

290

370

if(rc != GPG_ERR_NO_ERROR){

291

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

292

gpgme_strsource(rc), gpgme_strerror(rc));

371

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

372

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

373

gpgme_strsource(rc), gpgme_strerror(rc));

293

374

gpgme_data_release(dh_crypto);

294

375

return -1;

295

376

}

296

377

297

378

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

298

379

data buffer */

299

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

380

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

300

381

if(rc != GPG_ERR_NO_ERROR){

301

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

302

gpgme_strsource(rc), gpgme_strerror(rc));

382

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

383

gpgme_strsource(rc), gpgme_strerror(rc));

303

384

plaintext_length = -1;

304

385

if(debug){

305

386

gpgme_decrypt_result_t result;

306

result = gpgme_op_decrypt_result(mc.ctx);

387

result = gpgme_op_decrypt_result(mc->ctx);

307

388

if(result == NULL){

308

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

389

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

309

390

} else {

310

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

311

result->unsupported_algorithm);

312

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

313

result->wrong_key_usage);

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);

314

395

if(result->file_name != NULL){

315

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

396

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

316

397

}

317

398

gpgme_recipient_t recipient;

318

399

recipient = result->recipients;

319

400

while(recipient != NULL){

320

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

321

gpgme_pubkey_algo_name(recipient->pubkey_algo));

322

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

323

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

324

recipient->status == GPG_ERR_NO_SECKEY

325

? "No" : "Yes");

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");

326

408

recipient = recipient->next;

327

409

}

328

410

}

331

413

}

332

414

333

415

if(debug){

334

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

416

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

335

417

}

336

418

337

419

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

338

420

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

339

perror("gpgme_data_seek");

421

perror_plus("gpgme_data_seek");

340

422

plaintext_length = -1;

341

423

goto decrypt_end;

342

424

}

344

426

*plaintext = NULL;

345

427

while(true){

346

428

plaintext_capacity = incbuffer(plaintext,

347

(size_t)plaintext_length,

348

plaintext_capacity);

429

(size_t)plaintext_length,

430

plaintext_capacity);

349

431

if(plaintext_capacity == 0){

350

perror("incbuffer");

351

plaintext_length = -1;

352

goto decrypt_end;

432

perror_plus("incbuffer");

433

plaintext_length = -1;

434

goto decrypt_end;

353

435

}

354

436

355

437

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

360

442

break;

361

443

}

362

444

if(ret < 0){

363

perror("gpgme_data_read");

445

perror_plus("gpgme_data_read");

364

446

plaintext_length = -1;

365

447

goto decrypt_end;

366

448

}

368

450

}

369

451

370

452

if(debug){

371

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

453

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

372

454

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

373

455

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

374

456

}

386

468

}

387

469

388

470

static const char * safer_gnutls_strerror(int value){

389

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

390

-Wunreachable-code */

471

const char *ret = gnutls_strerror(value);

391

472

if(ret == NULL)

392

473

ret = "(unknown)";

393

474

return ret;

396

477

/* GnuTLS log function callback */

397

478

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

398

479

const char* string){

399

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

480

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

400

481

}

401

482

402

483

static int init_gnutls_global(const char *pubkeyfilename,

403

const char *seckeyfilename){

484

const char *seckeyfilename,

485

mandos_context *mc){

404

486

int ret;

405

487

406

488

if(debug){

407

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

489

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

408

490

}

409

491

410

492

ret = gnutls_global_init();

411

493

if(ret != GNUTLS_E_SUCCESS){

412

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

413

safer_gnutls_strerror(ret));

494

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

495

safer_gnutls_strerror(ret));

414

496

return -1;

415

497

}

416

498

423

505

}

424

506

425

507

/* OpenPGP credentials */

426

gnutls_certificate_allocate_credentials(&mc.cred);

508

ret = gnutls_certificate_allocate_credentials(&mc->cred);

427

509

if(ret != GNUTLS_E_SUCCESS){

428

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

429

from

430

-Wunreachable-code

431

*/

432

safer_gnutls_strerror(ret));

510

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

511

safer_gnutls_strerror(ret));

433

512

gnutls_global_deinit();

434

513

return -1;

435

514

}

436

515

437

516

if(debug){

438

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

439

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

440

seckeyfilename);

517

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

518

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

519

pubkeyfilename,

520

seckeyfilename);

441

521

}

442

522

443

523

ret = gnutls_certificate_set_openpgp_key_file

444

(mc.cred, pubkeyfilename, seckeyfilename,

524

(mc->cred, pubkeyfilename, seckeyfilename,

445

525

GNUTLS_OPENPGP_FMT_BASE64);

446

526

if(ret != GNUTLS_E_SUCCESS){

447

fprintf(stderr,

448

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

449

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

450

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

451

safer_gnutls_strerror(ret));

527

fprintf_plus(stderr,

528

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

529

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

530

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

531

safer_gnutls_strerror(ret));

452

532

goto globalfail;

453

533

}

454

534

455

535

/* GnuTLS server initialization */

456

ret = gnutls_dh_params_init(&mc.dh_params);

536

ret = gnutls_dh_params_init(&mc->dh_params);

457

537

if(ret != GNUTLS_E_SUCCESS){

458

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

459

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

538

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

539

" initialization: %s\n",

540

safer_gnutls_strerror(ret));

460

541

goto globalfail;

461

542

}

462

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

543

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

463

544

if(ret != GNUTLS_E_SUCCESS){

464

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

465

safer_gnutls_strerror(ret));

545

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

546

safer_gnutls_strerror(ret));

466

547

goto globalfail;

467

548

}

468

549

469

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

550

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

470

551

471

552

return 0;

472

553

473

554

globalfail:

474

555

475

gnutls_certificate_free_credentials(mc.cred);

556

gnutls_certificate_free_credentials(mc->cred);

476

557

gnutls_global_deinit();

477

gnutls_dh_params_deinit(mc.dh_params);

558

gnutls_dh_params_deinit(mc->dh_params);

478

559

return -1;

479

560

}

480

561

481

static int init_gnutls_session(gnutls_session_t *session){

562

static int init_gnutls_session(gnutls_session_t *session,

563

mandos_context *mc){

482

564

int ret;

483

565

/* GnuTLS session creation */

484

566

do {

488

570

}

489

571

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

490

572

if(ret != GNUTLS_E_SUCCESS){

491

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

492

safer_gnutls_strerror(ret));

573

fprintf_plus(stderr,

574

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

575

safer_gnutls_strerror(ret));

493

576

}

494

577

495

578

{

496

579

const char *err;

497

580

do {

498

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

581

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

499

582

if(quit_now){

500

583

gnutls_deinit(*session);

501

584

return -1;

502

585

}

503

586

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

504

587

if(ret != GNUTLS_E_SUCCESS){

505

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

506

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

507

safer_gnutls_strerror(ret));

588

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

589

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

590

safer_gnutls_strerror(ret));

508

591

gnutls_deinit(*session);

509

592

return -1;

510

593

}

512

595

513

596

do {

514

597

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

515

mc.cred);

598

mc->cred);

516

599

if(quit_now){

517

600

gnutls_deinit(*session);

518

601

return -1;

519

602

}

520

603

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

521

604

if(ret != GNUTLS_E_SUCCESS){

522

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

523

safer_gnutls_strerror(ret));

605

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

606

safer_gnutls_strerror(ret));

524

607

gnutls_deinit(*session);

525

608

return -1;

526

609

}

528

611

/* ignore client certificate if any. */

529

612

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

530

613

531

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

614

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

532

615

533

616

return 0;

534

617

}

538

621

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

539

622

540

623

/* Called when a Mandos server is found */

541

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

624

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

542

625

AvahiIfIndex if_index,

543

int af){

626

int af, mandos_context *mc){

544

627

int ret, tcp_sd = -1;

545

628

ssize_t sret;

546

629

union {

571

654

pf = PF_INET;

572

655

break;

573

656

default:

574

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

657

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

575

658

errno = EINVAL;

576

659

return -1;

577

660

}

578

661

579

ret = init_gnutls_session(&session);

662

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

663

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

664

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

665

bool match = false;

666

{

667

char *interface = NULL;

668

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

669

interface))){

670

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

671

match = true;

672

break;

673

}

674

}

675

}

676

if(not match){

677

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

678

connect to the server */

679

if(debug){

680

char interface[IF_NAMESIZE];

681

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

682

perror_plus("if_indextoname");

683

} else {

684

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

685

" \"%s\"\n",

686

if_indextoname((unsigned int)if_index,

687

interface));

688

}

689

}

690

return -1;

691

}

692

}

693

694

ret = init_gnutls_session(&session, mc);

580

695

if(ret != 0){

581

696

return -1;

582

697

}

583

698

584

699

if(debug){

585

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

586

"\n", ip, port);

700

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

701

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

587

702

}

588

703

589

704

tcp_sd = socket(pf, SOCK_STREAM, 0);

590

705

if(tcp_sd < 0){

591

706

int e = errno;

592

perror("socket");

707

perror_plus("socket");

593

708

errno = e;

594

709

goto mandos_end;

595

710

}

609

724

}

610

725

if(ret < 0 ){

611

726

int e = errno;

612

perror("inet_pton");

727

perror_plus("inet_pton");

613

728

errno = e;

614

729

goto mandos_end;

615

730

}

616

731

if(ret == 0){

617

732

int e = errno;

618

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

733

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

619

734

errno = e;

620

735

goto mandos_end;

621

736

}

622

737

if(af == AF_INET6){

623

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

624

-Wconversion and

625

-Wunreachable-code */

626

738

to.in6.sin6_port = htons(port);

739

#ifdef __GNUC__

740

#pragma GCC diagnostic push

741

#pragma GCC diagnostic ignored "-Wstrict-aliasing"

742

#endif

627

743

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

628

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

629

-Wunreachable-code*/

744

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

745

#ifdef __GNUC__

746

#pragma GCC diagnostic pop

747

#endif

630

748

if(if_index == AVAHI_IF_UNSPEC){

631

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

632

" without a network interface\n");

749

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

750

" incomplete without a network interface\n");

633

751

errno = EINVAL;

634

752

goto mandos_end;

635

753

}

637

755

to.in6.sin6_scope_id = (uint32_t)if_index;

638

756

}

639

757

} else {

640

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

641

-Wconversion and

642

-Wunreachable-code */

758

to.in.sin_port = htons(port);

643

759

}

644

760

645

761

if(quit_now){

651

767

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

652

768

char interface[IF_NAMESIZE];

653

769

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

654

perror("if_indextoname");

770

perror_plus("if_indextoname");

655

771

} else {

656

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

657

ip, interface, port);

772

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

773

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

658

774

}

659

775

} else {

660

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

661

port);

776

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

777

ip, (uintmax_t)port);

662

778

}

663

779

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

664

780

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

671

787

sizeof(addrstr));

672

788

}

673

789

if(pcret == NULL){

674

perror("inet_ntop");

790

perror_plus("inet_ntop");

675

791

} else {

676

792

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

677

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

793

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

678

794

}

679

795

}

680

796

}

692

808

if(ret < 0){

693

809

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

694

810

int e = errno;

695

perror("connect");

811

perror_plus("connect");

696

812

errno = e;

697

813

}

698

814

goto mandos_end;

708

824

while(true){

709

825

size_t out_size = strlen(out);

710

826

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

711

out_size - written));

827

out_size - written));

712

828

if(ret == -1){

713

829

int e = errno;

714

perror("write");

830

perror_plus("write");

715

831

errno = e;

716

832

goto mandos_end;

717

833

}

734

850

}

735

851

736

852

if(debug){

737

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

853

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

738

854

}

739

855

740

856

if(quit_now){

742

858

goto mandos_end;

743

859

}

744

860

745

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

861

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

862

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

863

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

864

gnutls_transport_set_ptr(session,

865

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

746

866

747

867

if(quit_now){

748

868

errno = EINTR;

759

879

760

880

if(ret != GNUTLS_E_SUCCESS){

761

881

if(debug){

762

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

882

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

763

883

gnutls_perror(ret);

764

884

}

765

885

errno = EPROTO;

769

889

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

770

890

771

891

if(debug){

772

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

773

ip);

892

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

893

" %s\n", ip);

774

894

}

775

895

776

896

while(true){

781

901

}

782

902

783

903

buffer_capacity = incbuffer(&buffer, buffer_length,

784

buffer_capacity);

904

buffer_capacity);

785

905

if(buffer_capacity == 0){

786

906

int e = errno;

787

perror("incbuffer");

907

perror_plus("incbuffer");

788

908

errno = e;

789

909

goto mandos_end;

790

910

}

814

934

}

815

935

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

816

936

if(ret < 0){

817

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

937

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

938

"***\n");

818

939

gnutls_perror(ret);

819

940

errno = EPROTO;

820

941

goto mandos_end;

821

942

}

822

943

break;

823

944

default:

824

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

825

" encrypted session with Mandos server\n");

945

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

946

" encrypted session with Mandos server\n");

826

947

gnutls_bye(session, GNUTLS_SHUT_RDWR);

827

948

errno = EIO;

828

949

goto mandos_end;

833

954

}

834

955

835

956

if(debug){

836

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

957

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

837

958

}

838

959

839

960

if(quit_now){

851

972

852

973

if(buffer_length > 0){

853

974

ssize_t decrypted_buffer_size;

854

decrypted_buffer_size = pgp_packet_decrypt(buffer,

855

buffer_length,

856

&decrypted_buffer);

975

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

976

&decrypted_buffer, mc);

857

977

if(decrypted_buffer_size >= 0){

858

978

859

979

written = 0;

869

989

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

870

990

int e = errno;

871

991

if(debug){

872

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

873

strerror(errno));

992

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

993

strerror(errno));

874

994

}

875

995

errno = e;

876

996

goto mandos_end;

895

1015

if(e == 0){

896

1016

e = errno;

897

1017

}

898

perror("close");

1018

perror_plus("close");

899

1019

}

900

1020

gnutls_deinit(session);

1021

errno = e;

901

1022

if(quit_now){

902

e = EINTR;

1023

errno = EINTR;

903

1024

retval = -1;

904

1025

}

905

errno = e;

906

1026

}

907

1027

return retval;

908

1028

}

920

1040

AVAHI_GCC_UNUSED AvahiStringList *txt,

921

1041

AVAHI_GCC_UNUSED AvahiLookupResultFlags

922

1042

flags,

923

AVAHI_GCC_UNUSED void* userdata){

924

assert(r);

1043

void* mc){

1044

if(r == NULL){

1045

return;

1046

}

925

1047

926

1048

/* Called whenever a service has been resolved successfully or

927

1049

timed out */

933

1055

switch(event){

934

1056

default:

935

1057

case AVAHI_RESOLVER_FAILURE:

936

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

937

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

938

avahi_strerror(avahi_server_errno(mc.server)));

1058

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

1059

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

1060

domain,

1061

avahi_strerror(avahi_server_errno

1062

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

939

1063

break;

940

1064

941

1065

case AVAHI_RESOLVER_FOUND:

943

1067

char ip[AVAHI_ADDRESS_STR_MAX];

944

1068

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

945

1069

if(debug){

946

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

947

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

948

ip, (intmax_t)interface, port);

1070

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

1071

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

1072

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

949

1073

}

950

int ret = start_mandos_communication(ip, port, interface,

951

avahi_proto_to_af(proto));

1074

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

1075

interface,

1076

avahi_proto_to_af(proto),

1077

mc);

952

1078

if(ret == 0){

953

avahi_simple_poll_quit(mc.simple_poll);

1079

avahi_simple_poll_quit(simple_poll);

1080

} else {

1081

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

1082

avahi_proto_to_af(proto),

1083

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

1084

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

1085

" list\n", name);

1086

}

954

1087

}

955

1088

}

956

1089

}

966

1099

const char *domain,

967

1100

AVAHI_GCC_UNUSED AvahiLookupResultFlags

968

1101

flags,

969

AVAHI_GCC_UNUSED void* userdata){

970

assert(b);

1102

void* mc){

1103

if(b == NULL){

1104

return;

1105

}

971

1106

972

1107

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

973

1108

is removed from the LAN */

980

1115

default:

981

1116

case AVAHI_BROWSER_FAILURE:

982

1117

983

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

984

avahi_strerror(avahi_server_errno(mc.server)));

985

avahi_simple_poll_quit(mc.simple_poll);

1118

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

1119

avahi_strerror(avahi_server_errno

1120

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

1121

avahi_simple_poll_quit(simple_poll);

986

1122

return;

987

1123

988

1124

case AVAHI_BROWSER_NEW:

991

1127

the callback function is called the Avahi server will free the

992

1128

resolver for us. */

993

1129

994

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

995

name, type, domain, protocol, 0,

996

resolve_callback, NULL) == NULL)

997

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

998

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

1130

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

1131

interface, protocol, name, type,

1132

domain, protocol, 0,

1133

resolve_callback, mc) == NULL)

1134

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

1135

" %s\n", name,

1136

avahi_strerror(avahi_server_errno

1137

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

999

1138

break;

1000

1139

1001

1140

case AVAHI_BROWSER_REMOVE:

1004

1143

case AVAHI_BROWSER_ALL_FOR_NOW:

1005

1144

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1006

1145

if(debug){

1007

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

1146

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

1147

" searching...\n");

1008

1148

}

1009

1149

break;

1010

1150

}

1011

1151

}

1012

1152

1013

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

1153

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

1014

1154

static void handle_sigterm(int sig){

1015

1155

if(quit_now){

1016

1156

return;

1018

1158

quit_now = 1;

1019

1159

signal_received = sig;

1020

1160

int old_errno = errno;

1021

if(mc.simple_poll != NULL){

1022

avahi_simple_poll_quit(mc.simple_poll);

1161

/* set main loop to exit */

1162

if(simple_poll != NULL){

1163

avahi_simple_poll_quit(simple_poll);

1023

1164

}

1024

1165

errno = old_errno;

1025

1166

}

1026

1167

1168

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

1169

int ret;

1170

error_t ret_errno;

1171

1172

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

1173

if(s < 0){

1174

ret_errno = errno;

1175

perror_plus("socket");

1176

errno = ret_errno;

1177

return false;

1178

}

1179

strcpy(ifr->ifr_name, ifname);

1180

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1181

if(ret == -1){

1182

if(debug){

1183

ret_errno = errno;

1184

perror_plus("ioctl SIOCGIFFLAGS");

1185

errno = ret_errno;

1186

}

1187

return false;

1188

}

1189

return true;

1190

}

1191

1192

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

1193

1194

/* Reject the loopback device */

1195

if(ifr->ifr_flags & IFF_LOOPBACK){

1196

if(debug){

1197

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

1198

ifname);

1199

}

1200

return false;

1201

}

1202

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

1203

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

1204

if(debug){

1205

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

1206

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

1207

}

1208

return true;

1209

}

1210

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

1211

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

1212

if(debug){

1213

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1214

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

1215

}

1216

return false;

1217

}

1218

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

1219

if(ifr->ifr_flags & IFF_NOARP){

1220

if(debug){

1221

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

1222

ifname);

1223

}

1224

return false;

1225

}

1226

1227

/* Accept this device */

1228

if(debug){

1229

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

1230

}

1231

return true;

1232

}

1233

1027

1234

/*

1028

1235

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

1029

1236

* corresponds to an acceptable network device.

1030

1237

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

1031

1238

*/

1032

1239

int good_interface(const struct dirent *if_entry){

1033

ssize_t ssret;

1034

char *flagname = NULL;

1035

int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,

1036

if_entry->d_name);

1037

if(ret < 0){

1038

perror("asprintf");

1039

return 0;

1040

}

1041

1240

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

1042

1241

return 0;

1043

1242

}

1044

int flags_fd = (int)TEMP_FAILURE_RETRY(open(flagname, O_RDONLY));

1045

if(flags_fd == -1){

1046

perror("open");

1047

return 0;

1048

}

1049

typedef short ifreq_flags; /* ifreq.ifr_flags in netdevice(7) */

1050

/* read line from flags_fd */

1051

ssize_t to_read = (sizeof(ifreq_flags)*2)+3; /* "0x1003\n" */

1052

char *flagstring = malloc((size_t)to_read+1); /* +1 for final \0 */

1053

flagstring[(size_t)to_read] = '\0';

1054

if(flagstring == NULL){

1055

perror("malloc");

1056

close(flags_fd);

1057

return 0;

1058

}

1059

while(to_read > 0){

1060

ssret = (ssize_t)TEMP_FAILURE_RETRY(read(flags_fd, flagstring,

1061

(size_t)to_read));

1062

if(ssret == -1){

1063

perror("read");

1064

free(flagstring);

1065

close(flags_fd);

1066

return 0;

1067

}

1068

to_read -= ssret;

1069

if(ssret == 0){

1243

1244

struct ifreq ifr;

1245

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

1246

if(debug){

1247

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

1248

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

1249

}

1250

return 0;

1251

}

1252

1253

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

1254

return 0;

1255

}

1256

return 1;

1257

}

1258

1259

/*

1260

* This function determines if a network interface is up.

1261

*/

1262

bool interface_is_up(const char *interface){

1263

struct ifreq ifr;

1264

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

1265

if(debug){

1266

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

1267

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

1268

}

1269

return false;

1270

}

1271

1272

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

1273

}

1274

1275

/*

1276

* This function determines if a network interface is running

1277

*/

1278

bool interface_is_running(const char *interface){

1279

struct ifreq ifr;

1280

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

1281

if(debug){

1282

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

1283

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

1284

}

1285

return false;

1286

}

1287

1288

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

1289

}

1290

1291

int notdotentries(const struct dirent *direntry){

1292

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

1293

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

1294

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

1295

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

1296

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

1297

return 0;

1298

}

1299

return 1;

1300

}

1301

1302

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

1303

int runnable_hook(const struct dirent *direntry){

1304

int ret;

1305

size_t sret;

1306

struct stat st;

1307

1308

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

1309

/* Empty name? */

1310

return 0;

1311

}

1312

1313

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

1314

"abcdefghijklmnopqrstuvwxyz"

1315

"0123456789"

1316

"_-");

1317

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

1318

/* Contains non-allowed characters */

1319

if(debug){

1320

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

1321

direntry->d_name);

1322

}

1323

return 0;

1324

}

1325

1326

char *fullname = NULL;

1327

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

1328

if(ret < 0){

1329

perror_plus("asprintf");

1330

return 0;

1331

}

1332

1333

ret = stat(fullname, &st);

1334

if(ret == -1){

1335

if(debug){

1336

perror_plus("Could not stat hook");

1337

}

1338

return 0;

1339

}

1340

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

1341

/* Not a regular file */

1342

if(debug){

1343

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

1344

direntry->d_name);

1345

}

1346

return 0;

1347

}

1348

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

1349

/* Not executable */

1350

if(debug){

1351

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

1352

direntry->d_name);

1353

}

1354

return 0;

1355

}

1356

if(debug){

1357

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

1358

direntry->d_name);

1359

}

1360

return 1;

1361

}

1362

1363

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1364

mandos_context *mc){

1365

int ret;

1366

struct timespec now;

1367

struct timespec waited_time;

1368

intmax_t block_time;

1369

1370

while(true){

1371

if(mc->current_server == NULL){

1372

if (debug){

1373

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

1374

" No timeout!\n");

1375

}

1376

ret = avahi_simple_poll_iterate(s, -1);

1377

} else {

1378

if (debug){

1379

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

1380

" it, or wait\n");

1381

}

1382

/* the current time */

1383

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1384

if(ret == -1){

1385

perror_plus("clock_gettime");

1386

return -1;

1387

}

1388

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

1389

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

1390

waited_time.tv_sec = (now.tv_sec

1391

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

1392

waited_time.tv_nsec = (now.tv_nsec

1393

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

1394

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

1395

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

1396

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

1397

block_time = ((retry_interval

1398

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

1399

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

1400

1401

if (debug){

1402

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

1403

block_time);

1404

}

1405

1406

if(block_time <= 0){

1407

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

1408

mc->current_server->port,

1409

mc->current_server->if_index,

1410

mc->current_server->af, mc);

1411

if(ret == 0){

1412

avahi_simple_poll_quit(s);

1413

return 0;

1414

}

1415

ret = clock_gettime(CLOCK_MONOTONIC,

1416

&mc->current_server->last_seen);

1417

if(ret == -1){

1418

perror_plus("clock_gettime");

1419

return -1;

1420

}

1421

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

1422

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

1423

servers, but don't block */

1424

}

1425

1426

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

1427

}

1428

if(ret != 0){

1429

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

1430

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

1431

}

1432

}

1433

}

1434

}

1435

1436

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

1437

error_t raise_privileges(void){

1438

error_t old_errno = errno;

1439

error_t ret_errno = 0;

1440

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

1441

ret_errno = errno;

1442

perror_plus("seteuid");

1443

}

1444

errno = old_errno;

1445

return ret_errno;

1446

}

1447

1448

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

1449

error_t raise_privileges_permanently(void){

1450

error_t old_errno = errno;

1451

error_t ret_errno = raise_privileges();

1452

if(ret_errno != 0){

1453

errno = old_errno;

1454

return ret_errno;

1455

}

1456

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

1457

ret_errno = errno;

1458

perror_plus("seteuid");

1459

}

1460

errno = old_errno;

1461

return ret_errno;

1462

}

1463

1464

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

1465

error_t lower_privileges(void){

1466

error_t old_errno = errno;

1467

error_t ret_errno = 0;

1468

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

1469

ret_errno = errno;

1470

perror_plus("seteuid");

1471

}

1472

errno = old_errno;

1473

return ret_errno;

1474

}

1475

1476

/* Lower privileges permanently */

1477

error_t lower_privileges_permanently(void){

1478

error_t old_errno = errno;

1479

error_t ret_errno = 0;

1480

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

1481

ret_errno = errno;

1482

perror_plus("setuid");

1483

}

1484

errno = old_errno;

1485

return ret_errno;

1486

}

1487

1488

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

1489

const float delay){

1490

struct dirent **direntries;

1491

struct dirent *direntry;

1492

int ret;

1493

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

1494

alphasort);

1495

if(numhooks == -1){

1496

if(errno == ENOENT){

1497

if(debug){

1498

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

1499

" found\n", hookdir);

1500

}

1501

} else {

1502

perror_plus("scandir");

1503

}

1504

} else {

1505

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

1506

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

1507

direntry = direntries[i];

1508

char *fullname = NULL;

1509

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

1510

if(ret < 0){

1511

perror_plus("asprintf");

1512

continue;

1513

}

1514

if(debug){

1515

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

1516

direntry->d_name);

1517

}

1518

pid_t hook_pid = fork();

1519

if(hook_pid == 0){

1520

/* Child */

1521

/* Raise privileges */

1522

raise_privileges_permanently();

1523

/* Set group */

1524

errno = 0;

1525

ret = setgid(0);

1526

if(ret == -1){

1527

perror_plus("setgid");

1528

}

1529

/* Reset supplementary groups */

1530

errno = 0;

1531

ret = setgroups(0, NULL);

1532

if(ret == -1){

1533

perror_plus("setgroups");

1534

}

1535

dup2(devnull, STDIN_FILENO);

1536

close(devnull);

1537

dup2(STDERR_FILENO, STDOUT_FILENO);

1538

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

1539

if(ret == -1){

1540

perror_plus("setenv");

1541

_exit(EX_OSERR);

1542

}

1543

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

1544

if(ret == -1){

1545

perror_plus("setenv");

1546

_exit(EX_OSERR);

1547

}

1548

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

1549

if(ret == -1){

1550

perror_plus("setenv");

1551

_exit(EX_OSERR);

1552

}

1553

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

1554

if(ret == -1){

1555

perror_plus("setenv");

1556

_exit(EX_OSERR);

1557

}

1558

char *delaystring;

1559

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

1560

if(ret == -1){

1561

perror_plus("asprintf");

1562

_exit(EX_OSERR);

1563

}

1564

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

1565

if(ret == -1){

1566

free(delaystring);

1567

perror_plus("setenv");

1568

_exit(EX_OSERR);

1569

}

1570

free(delaystring);

1571

if(connect_to != NULL){

1572

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

1573

if(ret == -1){

1574

perror_plus("setenv");

1575

_exit(EX_OSERR);

1576

}

1577

}

1578

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

1579

perror_plus("execl");

1580

_exit(EXIT_FAILURE);

1581

}

1582

} else {

1583

int status;

1584

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

1585

perror_plus("waitpid");

1586

free(fullname);

1587

continue;

1588

}

1589

if(WIFEXITED(status)){

1590

if(WEXITSTATUS(status) != 0){

1591

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

1592

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

1593

WEXITSTATUS(status));

1594

free(fullname);

1595

continue;

1596

}

1597

} else if(WIFSIGNALED(status)){

1598

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

1599

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

1600

WTERMSIG(status));

1601

free(fullname);

1602

continue;

1603

} else {

1604

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

1605

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

1606

free(fullname);

1607

continue;

1608

}

1609

}

1610

free(fullname);

1611

if(debug){

1612

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

1613

direntry->d_name);

1614

}

1615

}

1616

close(devnull);

1617

}

1618

return true;

1619

}

1620

1621

error_t bring_up_interface(const char *const interface,

1622

const float delay){

1623

int sd = -1;

1624

error_t old_errno = errno;

1625

error_t ret_errno = 0;

1626

int ret, ret_setflags;

1627

struct ifreq network;

1628

unsigned int if_index = if_nametoindex(interface);

1629

if(if_index == 0){

1630

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

1631

errno = old_errno;

1632

return ENXIO;

1633

}

1634

1635

if(quit_now){

1636

errno = old_errno;

1637

return EINTR;

1638

}

1639

1640

if(not interface_is_up(interface)){

1641

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

1642

ret_errno = errno;

1643

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

1644

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

1645

return ret_errno;

1646

}

1647

network.ifr_flags |= IFF_UP;

1648

1649

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1650

if(sd < 0){

1651

ret_errno = errno;

1652

perror_plus("socket");

1653

errno = old_errno;

1654

return ret_errno;

1655

}

1656

1657

if(quit_now){

1658

close(sd);

1659

errno = old_errno;

1660

return EINTR;

1661

}

1662

1663

if(debug){

1664

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

1665

interface);

1666

}

1667

1668

/* Raise priviliges */

1669

raise_privileges();

1670

1671

#ifdef __linux__

1672

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1673

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

1674

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

1675

bool restore_loglevel = true;

1676

if(ret_linux == -1){

1677

restore_loglevel = false;

1678

perror_plus("klogctl");

1679

}

1680

#endif /* __linux__ */

1681

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

1682

ret_errno = errno;

1683

#ifdef __linux__

1684

if(restore_loglevel){

1685

ret_linux = klogctl(7, NULL, 0);

1686

if(ret_linux == -1){

1687

perror_plus("klogctl");

1688

}

1689

}

1690

#endif /* __linux__ */

1691

1692

/* Lower privileges */

1693

lower_privileges();

1694

1695

/* Close the socket */

1696

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

1697

if(ret == -1){

1698

perror_plus("close");

1699

}

1700

1701

if(ret_setflags == -1){

1702

errno = ret_errno;

1703

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1704

errno = old_errno;

1705

return ret_errno;

1706

}

1707

} else if(debug){

1708

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

1709

interface);

1710

}

1711

1712

/* Sleep checking until interface is running.

1713

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

1714

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

1715

if(interface_is_running(interface)){

1070

1716

break;

1071

1717

}

1072

}

1073

close(flags_fd);

1074

intmax_t tmpmax;

1075

char *tmp;

1076

errno = 0;

1077

tmpmax = strtoimax(flagstring, &tmp, 0);

1078

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

1079

and not (isspace(*tmp)))

1080

or tmpmax != (ifreq_flags)tmpmax){

1081

if(debug){

1082

fprintf(stderr, "Invalid flags \"%s\" for interface \"%s\"\n",

1083

flagstring, if_entry->d_name);

1084

}

1085

free(flagstring);

1086

return 0;

1087

}

1088

free(flagstring);

1089

ifreq_flags flags = (ifreq_flags)tmpmax;

1090

/* Reject the loopback device */

1091

if(flags & IFF_LOOPBACK){

1092

if(debug){

1093

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

1094

if_entry->d_name);

1095

}

1096

return 0;

1097

}

1098

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

1099

if(connect_to != NULL and (flags & IFF_POINTOPOINT)){

1100

if(debug){

1101

fprintf(stderr, "Accepting point-to-point interface \"%s\"\n",

1102

if_entry->d_name);

1103

}

1104

return 1;

1105

}

1106

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

1107

if(not (flags & IFF_BROADCAST)){

1108

if(debug){

1109

fprintf(stderr, "Rejecting non-broadcast interface \"%s\"\n",

1110

if_entry->d_name);

1111

}

1112

return 0;

1113

}

1114

/* Accept this device */

1115

if(debug){

1116

fprintf(stderr, "Interface \"%s\" is acceptable\n",

1117

if_entry->d_name);

1118

}

1119

return 1;

1718

struct timespec sleeptime = { .tv_nsec = 250000000 };

1719

ret = nanosleep(&sleeptime, NULL);

1720

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

1721

perror_plus("nanosleep");

1722

}

1723

}

1724

1725

errno = old_errno;

1726

return 0;

1727

}

1728

1729

error_t take_down_interface(const char *const interface){

1730

int sd = -1;

1731

error_t old_errno = errno;

1732

error_t ret_errno = 0;

1733

int ret, ret_setflags;

1734

struct ifreq network;

1735

unsigned int if_index = if_nametoindex(interface);

1736

if(if_index == 0){

1737

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

1738

errno = old_errno;

1739

return ENXIO;

1740

}

1741

if(interface_is_up(interface)){

1742

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

1743

ret_errno = errno;

1744

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

1745

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

1746

return ret_errno;

1747

}

1748

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

1749

1750

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1751

if(sd < 0){

1752

ret_errno = errno;

1753

perror_plus("socket");

1754

errno = old_errno;

1755

return ret_errno;

1756

}

1757

1758

if(debug){

1759

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

1760

interface);

1761

}

1762

1763

/* Raise priviliges */

1764

raise_privileges();

1765

1766

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

1767

ret_errno = errno;

1768

1769

/* Lower privileges */

1770

lower_privileges();

1771

1772

/* Close the socket */

1773

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

1774

if(ret == -1){

1775

perror_plus("close");

1776

}

1777

1778

if(ret_setflags == -1){

1779

errno = ret_errno;

1780

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1781

errno = old_errno;

1782

return ret_errno;

1783

}

1784

} else if(debug){

1785

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

1786

interface);

1787

}

1788

1789

errno = old_errno;

1790

return 0;

1120

1791

}

1121

1792

1122

1793

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

1794

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

1795

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

1796

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

1797

.interfaces = NULL, .interfaces_size = 0 };

1123

1798

AvahiSServiceBrowser *sb = NULL;

1124

int error;

1799

error_t ret_errno;

1125

1800

int ret;

1126

1801

intmax_t tmpmax;

1127

1802

char *tmp;

1128

1803

int exitcode = EXIT_SUCCESS;

1129

const char *interface = "";

1130

struct ifreq network;

1131

int sd = -1;

1132

bool take_down_interface = false;

1133

uid_t uid;

1134

gid_t gid;

1804

char *interfaces_to_take_down = NULL;

1805

size_t interfaces_to_take_down_size = 0;

1135

1806

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

1136

1807

bool tempdir_created = false;

1137

1808

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1138

1809

const char *seckey = PATHDIR "/" SECKEY;

1139

1810

const char *pubkey = PATHDIR "/" PUBKEY;

1811

char *interfaces_hooks = NULL;

1812

size_t interfaces_hooks_size = 0;

1140

1813

1141

1814

bool gnutls_initialized = false;

1142

1815

bool gpgme_initialized = false;

1143

1816

float delay = 2.5f;

1817

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

1818

retrying the same server again */

1144

1819

1145

1820

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1146

1821

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1152

1827

errno = 0;

1153

1828

ret = setgid(gid);

1154

1829

if(ret == -1){

1155

perror("setgid");

1830

perror_plus("setgid");

1156

1831

}

1157

1832

1158

1833

/* Lower user privileges (temporarily) */

1159

1834

errno = 0;

1160

1835

ret = seteuid(uid);

1161

1836

if(ret == -1){

1162

perror("seteuid");

1837

perror_plus("seteuid");

1163

1838

}

1164

1839

1165

1840

if(quit_now){

1200

1875

.arg = "SECONDS",

1201

1876

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

1202

1877

.group = 2 },

1878

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

1879

.arg = "SECONDS",

1880

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

1881

.group = 2 },

1882

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

1883

.arg = "DIR",

1884

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

1885

.group = 2 },

1203

1886

/*

1204

1887

* These reproduce what we would get without ARGP_NO_HELP

1205

1888

*/

1223

1906

connect_to = arg;

1224

1907

break;

1225

1908

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

1226

interface = arg;

1909

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

1910

arg, (int)',');

1911

if(ret_errno != 0){

1912

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

1913

}

1227

1914

break;

1228

1915

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

1229

1916

seckey = arg;

1249

1936

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

1250

1937

argp_error(state, "Bad delay");

1251

1938

}

1939

case 132: /* --retry */

1940

errno = 0;

1941

retry_interval = strtod(arg, &tmp);

1942

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

1943

or (retry_interval * 1000) > INT_MAX

1944

or retry_interval < 0){

1945

argp_error(state, "Bad retry interval");

1946

}

1947

break;

1948

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

1949

hookdir = arg;

1252

1950

break;

1253

1951

/*

1254

1952

* These reproduce what we would get without ARGP_NO_HELP

1261

1959

argp_state_help(state, state->out_stream,

1262

1960

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1263

1961

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

1264

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

1962

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

1265

1963

exit(argp_err_exit_status);

1266

1964

break;

1267

1965

default:

1282

1980

case ENOMEM:

1283

1981

default:

1284

1982

errno = ret;

1285

perror("argp_parse");

1983

perror_plus("argp_parse");

1286

1984

exitcode = EX_OSERR;

1287

1985

goto end;

1288

1986

case EINVAL:

1290

1988

goto end;

1291

1989

}

1292

1990

}

1991

1992

{

1993

/* Work around Debian bug #633582:

1994

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

1995

1996

/* Re-raise priviliges */

1997

if(raise_privileges() == 0){

1998

struct stat st;

1999

2000

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

2001

int seckey_fd = open(seckey, O_RDONLY);

2002

if(seckey_fd == -1){

2003

perror_plus("open");

2004

} else {

2005

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

2006

if(ret == -1){

2007

perror_plus("fstat");

2008

} else {

2009

if(S_ISREG(st.st_mode)

2010

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

2011

ret = fchown(seckey_fd, uid, gid);

2012

if(ret == -1){

2013

perror_plus("fchown");

2014

}

2015

}

2016

}

2017

TEMP_FAILURE_RETRY(close(seckey_fd));

2018

}

2019

}

2020

2021

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

2022

int pubkey_fd = open(pubkey, O_RDONLY);

2023

if(pubkey_fd == -1){

2024

perror_plus("open");

2025

} else {

2026

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

2027

if(ret == -1){

2028

perror_plus("fstat");

2029

} else {

2030

if(S_ISREG(st.st_mode)

2031

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

2032

ret = fchown(pubkey_fd, uid, gid);

2033

if(ret == -1){

2034

perror_plus("fchown");

2035

}

2036

}

2037

}

2038

TEMP_FAILURE_RETRY(close(pubkey_fd));

2039

}

2040

}

2041

2042

/* Lower privileges */

2043

lower_privileges();

2044

}

2045

}

2046

2047

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

2048

{

2049

char *interface = NULL;

2050

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

2051

interface))){

2052

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

2053

and if_nametoindex(interface) == 0){

2054

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

2055

fprintf_plus(stderr, "Not using nonexisting interface"

2056

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

2057

}

2058

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

2059

interface = NULL;

2060

}

2061

}

2062

}

2063

2064

/* Run network hooks */

2065

{

2066

if(mc.interfaces != NULL){

2067

interfaces_hooks = malloc(mc.interfaces_size);

2068

if(interfaces_hooks == NULL){

2069

perror_plus("malloc");

2070

goto end;

2071

}

2072

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

2073

interfaces_hooks_size = mc.interfaces_size;

2074

argz_stringify(interfaces_hooks, interfaces_hooks_size,

2075

(int)',');

2076

}

2077

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

2078

interfaces_hooks : "", delay)){

2079

goto end;

2080

}

2081

}

1293

2082

1294

2083

if(not debug){

1295

2084

avahi_set_log_function(empty_log);

1296

2085

}

1297

1298

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

1299

struct dirent **direntries;

1300

ret = scandir(sys_class_net, &direntries, good_interface,

1301

alphasort);

1302

if(ret >= 1){

1303

/* Pick the first good interface */

1304

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

1305

if(debug){

1306

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

1307

}

1308

if(interface == NULL){

1309

perror("malloc");

1310

free(direntries);

1311

exitcode = EXIT_FAILURE;

1312

goto end;

1313

}

1314

free(direntries);

1315

} else {

1316

free(direntries);

1317

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

1318

exitcode = EXIT_FAILURE;

1319

goto end;

1320

}

1321

}

1322

2086

1323

2087

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

1324

2088

from the signal handler */

1325

2089

/* Initialize the pseudo-RNG for Avahi */

1326

2090

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

1327

mc.simple_poll = avahi_simple_poll_new();

1328

if(mc.simple_poll == NULL){

1329

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

2091

simple_poll = avahi_simple_poll_new();

2092

if(simple_poll == NULL){

2093

fprintf_plus(stderr,

2094

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

1330

2095

exitcode = EX_UNAVAILABLE;

1331

2096

goto end;

1332

2097

}

1334

2099

sigemptyset(&sigterm_action.sa_mask);

1335

2100

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

1336

2101

if(ret == -1){

1337

perror("sigaddset");

2102

perror_plus("sigaddset");

1338

2103

exitcode = EX_OSERR;

1339

2104

goto end;

1340

2105

}

1341

2106

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

1342

2107

if(ret == -1){

1343

perror("sigaddset");

2108

perror_plus("sigaddset");

1344

2109

exitcode = EX_OSERR;

1345

2110

goto end;

1346

2111

}

1347

2112

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

1348

2113

if(ret == -1){

1349

perror("sigaddset");

2114

perror_plus("sigaddset");

1350

2115

exitcode = EX_OSERR;

1351

2116

goto end;

1352

2117

}

1356

2121

*/

1357

2122

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

1358

2123

if(ret == -1){

1359

perror("sigaction");

2124

perror_plus("sigaction");

1360

2125

return EX_OSERR;

1361

2126

}

1362

2127

if(old_sigterm_action.sa_handler != SIG_IGN){

1363

2128

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

1364

2129

if(ret == -1){

1365

perror("sigaction");

2130

perror_plus("sigaction");

1366

2131

exitcode = EX_OSERR;

1367

2132

goto end;

1368

2133

}

1369

2134

}

1370

2135

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

1371

2136

if(ret == -1){

1372

perror("sigaction");

2137

perror_plus("sigaction");

1373

2138

return EX_OSERR;

1374

2139

}

1375

2140

if(old_sigterm_action.sa_handler != SIG_IGN){

1376

2141

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

1377

2142

if(ret == -1){

1378

perror("sigaction");

2143

perror_plus("sigaction");

1379

2144

exitcode = EX_OSERR;

1380

2145

goto end;

1381

2146

}

1382

2147

}

1383

2148

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

1384

2149

if(ret == -1){

1385

perror("sigaction");

2150

perror_plus("sigaction");

1386

2151

return EX_OSERR;

1387

2152

}

1388

2153

if(old_sigterm_action.sa_handler != SIG_IGN){

1389

2154

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

1390

2155

if(ret == -1){

1391

perror("sigaction");

1392

exitcode = EX_OSERR;

1393

goto end;

1394

}

1395

}

1396

1397

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

1398

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

1399

if_index = (AvahiIfIndex) if_nametoindex(interface);

1400

if(if_index == 0){

1401

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

1402

exitcode = EX_UNAVAILABLE;

1403

goto end;

1404

}

1405

1406

if(quit_now){

1407

goto end;

1408

}

1409

1410

/* Re-raise priviliges */

1411

errno = 0;

1412

ret = seteuid(0);

1413

if(ret == -1){

1414

perror("seteuid");

1415

}

1416

1417

#ifdef __linux__

1418

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1419

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

1420

ret = klogctl(8, NULL, 5);

1421

bool restore_loglevel = true;

1422

if(ret == -1){

1423

restore_loglevel = false;

1424

perror("klogctl");

1425

}

1426

#endif /* __linux__ */

1427

1428

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1429

if(sd < 0){

1430

perror("socket");

1431

exitcode = EX_OSERR;

1432

#ifdef __linux__

1433

if(restore_loglevel){

1434

ret = klogctl(7, NULL, 0);

1435

if(ret == -1){

1436

perror("klogctl");

1437

}

1438

}

1439

#endif /* __linux__ */

1440

/* Lower privileges */

1441

errno = 0;

1442

ret = seteuid(uid);

1443

if(ret == -1){

1444

perror("seteuid");

1445

}

1446

goto end;

1447

}

1448

strcpy(network.ifr_name, interface);

1449

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

1450

if(ret == -1){

1451

perror("ioctl SIOCGIFFLAGS");

1452

#ifdef __linux__

1453

if(restore_loglevel){

1454

ret = klogctl(7, NULL, 0);

1455

if(ret == -1){

1456

perror("klogctl");

1457

}

1458

}

1459

#endif /* __linux__ */

1460

exitcode = EX_OSERR;

1461

/* Lower privileges */

1462

errno = 0;

1463

ret = seteuid(uid);

1464

if(ret == -1){

1465

perror("seteuid");

1466

}

1467

goto end;

1468

}

1469

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

1470

network.ifr_flags |= IFF_UP;

1471

take_down_interface = true;

1472

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

1473

if(ret == -1){

1474

take_down_interface = false;

1475

perror("ioctl SIOCSIFFLAGS +IFF_UP");

1476

exitcode = EX_OSERR;

1477

#ifdef __linux__

1478

if(restore_loglevel){

1479

ret = klogctl(7, NULL, 0);

1480

if(ret == -1){

1481

perror("klogctl");

2156

perror_plus("sigaction");

2157

exitcode = EX_OSERR;

2158

goto end;

2159

}

2160

}

2161

2162

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

2163

if(mc.interfaces == NULL){

2164

struct dirent **direntries;

2165

/* Look for any good interfaces */

2166

ret = scandir(sys_class_net, &direntries, good_interface,

2167

alphasort);

2168

if(ret >= 1){

2169

/* Add all found interfaces to interfaces list */

2170

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

2171

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

2172

direntries[i]->d_name);

2173

if(ret_errno != 0){

2174

perror_plus("argz_add");

2175

continue;

2176

}

2177

if(debug){

2178

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

2179

direntries[i]->d_name);

2180

}

2181

}

2182

free(direntries);

2183

} else {

2184

free(direntries);

2185

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

2186

exitcode = EXIT_FAILURE;

2187

goto end;

2188

}

2189

}

2190

2191

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

2192

{

2193

char *interface = NULL;

2194

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

2195

interface))){

2196

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

2197

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

2198

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

2199

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

2200

interface);

2201

interface = NULL;

2202

while((interface = argz_next(mc.interfaces,

2203

mc.interfaces_size, interface))){

2204

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

2205

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

2206

interface);

2207

interface = NULL;

1482

2208

}

1483

2209

}

1484

#endif /* __linux__ */

1485

/* Lower privileges */

1486

errno = 0;

1487

ret = seteuid(uid);

1488

if(ret == -1){

1489

perror("seteuid");

1490

}

1491

goto end;

1492

}

1493

}

1494

/* sleep checking until interface is running */

1495

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

1496

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

1497

if(ret == -1){

1498

perror("ioctl SIOCGIFFLAGS");

1499

} else if(network.ifr_flags & IFF_RUNNING){

1500

2210

break;

1501

2211

}

1502

struct timespec sleeptime = { .tv_nsec = 250000000 };

1503

ret = nanosleep(&sleeptime, NULL);

1504

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

1505

perror("nanosleep");

1506

}

1507

}

1508

if(not take_down_interface){

1509

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

1510

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

1511

if(ret == -1){

1512

perror("close");

1513

}

1514

}

1515

#ifdef __linux__

1516

if(restore_loglevel){

1517

/* Restores kernel loglevel to default */

1518

ret = klogctl(7, NULL, 0);

1519

if(ret == -1){

1520

perror("klogctl");

1521

}

1522

}

1523

#endif /* __linux__ */

1524

/* Lower privileges */

1525

errno = 0;

1526

if(take_down_interface){

1527

/* Lower privileges */

1528

ret = seteuid(uid);

1529

if(ret == -1){

1530

perror("seteuid");

1531

}

1532

} else {

1533

/* Lower privileges permanently */

1534

ret = setuid(uid);

1535

if(ret == -1){

1536

perror("setuid");

1537

}

1538

}

2212

bool interface_was_up = interface_is_up(interface);

2213

ret = bring_up_interface(interface, delay);

2214

if(not interface_was_up){

2215

if(ret != 0){

2216

errno = ret;

2217

perror_plus("Failed to bring up interface");

2218

} else {

2219

ret_errno = argz_add(&interfaces_to_take_down,

2220

&interfaces_to_take_down_size,

2221

interface);

2222

}

2223

}

2224

}

2225

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

2226

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

2227

}

2228

}

2229

2230

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

2231

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

2232

if(debug){

2233

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

2234

mc.interfaces);

2235

}

2236

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

1539

2237

}

1540

2238

1541

2239

if(quit_now){

1542

2240

goto end;

1543

2241

}

1544

2242

1545

ret = init_gnutls_global(pubkey, seckey);

2243

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

1546

2244

if(ret == -1){

1547

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

2245

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

1548

2246

exitcode = EX_UNAVAILABLE;

1549

2247

goto end;

1550

2248

} else {

1555

2253

goto end;

1556

2254

}

1557

2255

2256

if(mkdtemp(tempdir) == NULL){

2257

perror_plus("mkdtemp");

2258

goto end;

2259

}

1558

2260

tempdir_created = true;

1559

if(mkdtemp(tempdir) == NULL){

1560

tempdir_created = false;

1561

perror("mkdtemp");

1562

goto end;

1563

}

1564

2261

1565

2262

if(quit_now){

1566

2263

goto end;

1567

2264

}

1568

2265

1569

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

1570

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

2266

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

2267

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

1571

2268

exitcode = EX_UNAVAILABLE;

1572

2269

goto end;

1573

2270

} else {

1582

2279

/* Connect directly, do not use Zeroconf */

1583

2280

/* (Mainly meant for debugging) */

1584

2281

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

2282

1585

2283

if(address == NULL){

1586

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

2284

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

1587

2285

exitcode = EX_USAGE;

1588

2286

goto end;

1589

2287

}

1592

2290

goto end;

1593

2291

}

1594

2292

1595

uint16_t port;

2293

in_port_t port;

1596

2294

errno = 0;

1597

2295

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

1598

2296

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

1599

or tmpmax != (uint16_t)tmpmax){

1600

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

2297

or tmpmax != (in_port_t)tmpmax){

2298

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

1601

2299

exitcode = EX_USAGE;

1602

2300

goto end;

1603

2301

}

1604

2302

1605

2303

if(quit_now){

1606

2304

goto end;

1607

2305

}

1608

2306

1609

port = (uint16_t)tmpmax;

2307

port = (in_port_t)tmpmax;

1610

2308

*address = '\0';

1611

address = connect_to;

1612

2309

/* Colon in address indicates IPv6 */

1613

2310

int af;

1614

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

2311

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

1615

2312

af = AF_INET6;

2313

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

2314

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

2315

{

2316

connect_to++;

2317

address[-1] = '\0';

2318

}

1616

2319

} else {

1617

2320

af = AF_INET;

1618

2321

}

2322

address = connect_to;

1619

2323

1620

2324

if(quit_now){

1621

2325

goto end;

1622

2326

}

1623

2327

1624

2328

while(not quit_now){

1625

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

2329

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

2330

&mc);

1626

2331

if(quit_now or ret == 0){

1627

2332

break;

1628

2333

}

1629

sleep(15);

1630

};

1631

2334

if(debug){

2335

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

2336

(int)retry_interval);

2337

}

2338

sleep((unsigned int)retry_interval);

2339

}

2340

1632

2341

if (not quit_now){

1633

2342

exitcode = EXIT_SUCCESS;

1634

2343

}

1635

2344

1636

2345

goto end;

1637

2346

}

1638

2347

1650

2359

config.publish_domain = 0;

1651

2360

1652

2361

/* Allocate a new server */

1653

mc.server = avahi_server_new(avahi_simple_poll_get

1654

(mc.simple_poll), &config, NULL,

1655

NULL, &error);

2362

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2363

&config, NULL, NULL, &ret_errno);

1656

2364

1657

2365

/* Free the Avahi configuration data */

1658

2366

avahi_server_config_free(&config);

1660

2368

1661

2369

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

1662

2370

if(mc.server == NULL){

1663

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

1664

avahi_strerror(error));

2371

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

2372

avahi_strerror(ret_errno));

1665

2373

exitcode = EX_UNAVAILABLE;

1666

2374

goto end;

1667

2375

}

1673

2381

/* Create the Avahi service browser */

1674

2382

sb = avahi_s_service_browser_new(mc.server, if_index,

1675

2383

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1676

NULL, 0, browse_callback, NULL);

2384

NULL, 0, browse_callback,

2385

(void *)&mc);

1677

2386

if(sb == NULL){

1678

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

1679

avahi_strerror(avahi_server_errno(mc.server)));

2387

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

2388

avahi_strerror(avahi_server_errno(mc.server)));

1680

2389

exitcode = EX_UNAVAILABLE;

1681

2390

goto end;

1682

2391

}

1688

2397

/* Run the main loop */

1689

2398

1690

2399

if(debug){

1691

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

1692

}

1693

1694

avahi_simple_poll_loop(mc.simple_poll);

2400

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

2401

}

2402

2403

ret = avahi_loop_with_timeout(simple_poll,

2404

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

2405

if(debug){

2406

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

2407

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

2408

}

1695

2409

1696

2410

end:

1697

2411

1698

2412

if(debug){

1699

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

2413

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

1700

2414

}

1701

2415

1702

2416

/* Cleanup things */

2417

free(mc.interfaces);

2418

1703

2419

if(sb != NULL)

1704

2420

avahi_s_service_browser_free(sb);

1705

2421

1706

2422

if(mc.server != NULL)

1707

2423

avahi_server_free(mc.server);

1708

2424

1709

if(mc.simple_poll != NULL)

1710

avahi_simple_poll_free(mc.simple_poll);

2425

if(simple_poll != NULL)

2426

avahi_simple_poll_free(simple_poll);

1711

2427

1712

2428

if(gnutls_initialized){

1713

2429

gnutls_certificate_free_credentials(mc.cred);

1719

2435

gpgme_release(mc.ctx);

1720

2436

}

1721

2437

1722

/* Take down the network interface */

1723

if(take_down_interface){

1724

/* Re-raise priviliges */

1725

errno = 0;

1726

ret = seteuid(0);

1727

if(ret == -1){

1728

perror("seteuid");

2438

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

2439

has seen */

2440

if(mc.current_server != NULL){

2441

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

2442

while(mc.current_server != NULL){

2443

server *next = mc.current_server->next;

2444

free(mc.current_server);

2445

mc.current_server = next;

1729

2446

}

1730

if(geteuid() == 0){

1731

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

1732

if(ret == -1){

1733

perror("ioctl SIOCGIFFLAGS");

1734

} else if(network.ifr_flags & IFF_UP) {

1735

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

1736

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

1737

if(ret == -1){

1738

perror("ioctl SIOCSIFFLAGS -IFF_UP");

2447

}

2448

2449

/* Re-raise priviliges */

2450

{

2451

raise_privileges();

2452

2453

/* Run network hooks */

2454

run_network_hooks("stop", interfaces_hooks != NULL ?

2455

interfaces_hooks : "", delay);

2456

2457

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

2458

{

2459

char *interface = NULL;

2460

while((interface=argz_next(interfaces_to_take_down,

2461

interfaces_to_take_down_size,

2462

interface))){

2463

ret_errno = take_down_interface(interface);

2464

if(ret_errno != 0){

2465

errno = ret_errno;

2466

perror_plus("Failed to take down interface");

1739

2467

}

1740

2468

}

1741

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

1742

if(ret == -1){

1743

perror("close");

1744

}

1745

/* Lower privileges permanently */

1746

errno = 0;

1747

ret = setuid(uid);

1748

if(ret == -1){

1749

perror("setuid");

2469

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

2470

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

2471

" down\n");

1750

2472

}

1751

2473

}

2474

2475

lower_privileges_permanently();

1752

2476

}

1753

2477

1754

/* Removes the temp directory used by GPGME */

2478

free(interfaces_to_take_down);

2479

free(interfaces_hooks);

2480

2481

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

1755

2482

if(tempdir_created){

1756

DIR *d;

1757

struct dirent *direntry;

1758

d = opendir(tempdir);

1759

if(d == NULL){

1760

if(errno != ENOENT){

1761

perror("opendir");

1762

}

1763

} else {

1764

while(true){

1765

direntry = readdir(d);

1766

if(direntry == NULL){

1767

break;

1768

}

1769

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

1770

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

1771

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

1772

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

1773

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

1774

continue;

1775

}

2483

struct dirent **direntries = NULL;

2484

struct dirent *direntry = NULL;

2485

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

2486

alphasort);

2487

if (numentries > 0){

2488

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

2489

direntry = direntries[i];

1776

2490

char *fullname = NULL;

1777

2491

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

1778

2492

direntry->d_name);

1779

2493

if(ret < 0){

1780

perror("asprintf");

2494

perror_plus("asprintf");

1781

2495

continue;

1782

2496

}

1783

2497

ret = remove(fullname);

1784

2498

if(ret == -1){

1785

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

1786

strerror(errno));

2499

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

2500

strerror(errno));

1787

2501

}

1788

2502

free(fullname);

1789

2503

}

1790

closedir(d);

2504

}

2505

2506

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

2507

free(direntries);

2508

if (numentries == -1){

2509

perror_plus("scandir");

1791

2510

}

1792

2511

ret = rmdir(tempdir);

1793

2512

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

1794

perror("rmdir");

2513

perror_plus("rmdir");

1795

2514

}

1796

2515

}

1797

2516

1802

2521

&old_sigterm_action,

1803

2522

NULL));

1804

2523

if(ret == -1){

1805

perror("sigaction");

2524

perror_plus("sigaction");

1806

2525

}

1807

2526

do {

1808

2527

ret = raise(signal_received);

1809

2528

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

1810

2529

if(ret != 0){

1811

perror("raise");

2530

perror_plus("raise");

1812

2531

abort();

1813

2532

}

1814

2533

TEMP_FAILURE_RETRY(pause());