/mandos/trunk : revision 369

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

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*

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* Everything else is

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*

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

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

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* along with this program. If not, see

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

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*

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

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

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*/

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32

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

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

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stdout, ferror(), remove() */

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

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

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

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

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strtof(), abort() */

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

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srand(), strtof() */

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

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

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

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sockaddr_in6, PF_INET6,

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SOCK_STREAM, uid_t, gid_t, open(),

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opendir(), DIR */

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

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

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

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inet_pton(), connect() */

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

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#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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program_invocation_short_name */

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

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

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

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

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SIOCSIFFLAGS, if_indextoname(),

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if_nametoindex(), IF_NAMESIZE */

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*/

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

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

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

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

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setgid() */

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

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

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

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argp_state, struct argp,

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

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sigaction(), SIGTERM, sig_atomic_t,

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raise() */

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

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EX_NOHOST, EX_IOERR, EX_PROTOCOL */

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

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WEXITSTATUS(), WTERMSIG() */

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

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85

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#ifdef __linux__

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87

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

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105

init_gnutls_session(),

112

106

GNUTLS_* */

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107

#include <gnutls/openpgp.h>

114

/* 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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120

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

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121

#define SECKEY "seckey.txt"

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122

#define PUBKEY "pubkey.txt"

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

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123

131

124

bool debug = false;

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125

static const char mandos_protocol_version[] = "1";

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126

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

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

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

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char *connect_to = NULL;

137

const char *hookdir = HOOKDIR;

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uid_t uid = 65534;

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gid_t gid = 65534;

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141

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

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typedef struct server{

143

const char *ip;

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uint16_t port;

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AvahiIfIndex if_index;

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int af;

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struct timespec last_seen;

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struct server *next;

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struct server *prev;

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} server;

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

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128

152

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

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130

typedef struct {

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135

gnutls_dh_params_t dh_params;

159

136

const char *priority;

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137

gpgme_ctx_t ctx;

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server *current_server;

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138

} mandos_context;

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139

164

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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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142

.dh_bits = 1024, .priority = "SECURE256"

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

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.current_server = NULL };

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170

sig_atomic_t quit_now = 0;

171

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;

179

perror(print_text);

180

}

181

182

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

183

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

184

va_list ap;

185

va_start (ap, format);

186

187

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

188

program_invocation_short_name));

189

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

190

}

143

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

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144

192

145

/*

193

146

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

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148

* "buffer_length" is how much is already used.

196

149

*/

197

150

size_t incbuffer(char **buffer, size_t buffer_length,

198

size_t buffer_capacity){

151

size_t buffer_capacity){

199

152

if(buffer_length + BUFFER_SIZE > buffer_capacity){

200

153

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

201

154

if(buffer == NULL){

206

159

return buffer_capacity;

207

160

}

208

161

209

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

210

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

211

int af){

212

int ret;

213

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

214

if(new_server == NULL){

215

perror_plus("malloc");

216

return false;

217

}

218

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

219

.port = port,

220

.if_index = if_index,

221

.af = af };

222

if(new_server->ip == NULL){

223

perror_plus("strdup");

224

return false;

225

}

226

/* Special case of first server */

227

if (mc.current_server == NULL){

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new_server->next = new_server;

229

new_server->prev = new_server;

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mc.current_server = new_server;

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

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} else {

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new_server->next = mc.current_server;

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

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new_server->prev->next = new_server;

236

mc.current_server->prev = new_server;

237

}

238

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

239

if(ret == -1){

240

perror_plus("clock_gettime");

241

return false;

242

}

243

return true;

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}

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246

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/*

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163

* Initialize GPGME.

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164

*/

249

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

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const char *tempdir){

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static bool init_gpgme(const char *seckey,

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const char *pubkey, const char *tempdir){

251

167

gpgme_error_t rc;

252

168

gpgme_engine_info_t engine_info;

253

169

262

178

263

179

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

264

180

if(fd == -1){

265

perror_plus("open");

181

perror("open");

266

182

return false;

267

183

}

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184

269

185

rc = gpgme_data_new_from_fd(&pgp_data, fd);

270

186

if(rc != GPG_ERR_NO_ERROR){

271

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

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gpgme_strsource(rc), gpgme_strerror(rc));

187

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

188

gpgme_strsource(rc), gpgme_strerror(rc));

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189

return false;

274

190

}

275

191

276

192

rc = gpgme_op_import(mc.ctx, pgp_data);

277

193

if(rc != GPG_ERR_NO_ERROR){

278

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

279

gpgme_strsource(rc), gpgme_strerror(rc));

194

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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196

return false;

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197

}

282

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

284

200

if(ret == -1){

285

perror_plus("close");

201

perror("close");

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202

}

287

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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){

292

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

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

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}

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/* Init GPGME */

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gpgme_check_version(NULL);

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rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

298

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if(rc != GPG_ERR_NO_ERROR){

299

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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217

return false;

302

218

}

303

219

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

220

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

305

221

rc = gpgme_get_engine_info(&engine_info);

306

222

if(rc != GPG_ERR_NO_ERROR){

307

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

308

gpgme_strsource(rc), gpgme_strerror(rc));

223

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

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gpgme_strsource(rc), gpgme_strerror(rc));

309

225

return false;

310

226

}

311

227

while(engine_info != NULL){

317

233

engine_info = engine_info->next;

318

234

}

319

235

if(engine_info == NULL){

320

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

321

tempdir);

236

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

322

237

return false;

323

238

}

324

239

325

240

/* Create new GPGME "context" */

326

241

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

327

242

if(rc != GPG_ERR_NO_ERROR){

328

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

329

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

330

gpgme_strerror(rc));

243

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

244

gpgme_strsource(rc), gpgme_strerror(rc));

331

245

return false;

332

246

}

333

247

352

266

ssize_t plaintext_length = 0;

353

267

354

268

if(debug){

355

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

269

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

356

270

}

357

271

358

272

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

359

273

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

360

274

0);

361

275

if(rc != GPG_ERR_NO_ERROR){

362

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

363

gpgme_strsource(rc), gpgme_strerror(rc));

276

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

277

gpgme_strsource(rc), gpgme_strerror(rc));

364

278

return -1;

365

279

}

366

280

367

281

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

368

282

rc = gpgme_data_new(&dh_plain);

369

283

if(rc != GPG_ERR_NO_ERROR){

370

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

371

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

372

gpgme_strsource(rc), gpgme_strerror(rc));

284

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

285

gpgme_strsource(rc), gpgme_strerror(rc));

373

286

gpgme_data_release(dh_crypto);

374

287

return -1;

375

288

}

378

291

data buffer */

379

292

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

380

293

if(rc != GPG_ERR_NO_ERROR){

381

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

382

gpgme_strsource(rc), gpgme_strerror(rc));

294

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

295

gpgme_strsource(rc), gpgme_strerror(rc));

383

296

plaintext_length = -1;

384

297

if(debug){

385

298

gpgme_decrypt_result_t result;

386

299

result = gpgme_op_decrypt_result(mc.ctx);

387

300

if(result == NULL){

388

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

301

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

389

302

} else {

390

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

391

result->unsupported_algorithm);

392

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

393

result->wrong_key_usage);

303

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

304

result->unsupported_algorithm);

305

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

306

result->wrong_key_usage);

394

307

if(result->file_name != NULL){

395

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

308

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

396

309

}

397

310

gpgme_recipient_t recipient;

398

311

recipient = result->recipients;

399

312

while(recipient != NULL){

400

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

401

gpgme_pubkey_algo_name

402

(recipient->pubkey_algo));

403

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

404

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

405

recipient->status == GPG_ERR_NO_SECKEY

406

? "No" : "Yes");

313

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

314

gpgme_pubkey_algo_name(recipient->pubkey_algo));

315

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

316

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

317

recipient->status == GPG_ERR_NO_SECKEY

318

? "No" : "Yes");

407

319

recipient = recipient->next;

408

320

}

409

321

}

412

324

}

413

325

414

326

if(debug){

415

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

327

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

416

328

}

417

329

418

330

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

419

331

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

420

perror_plus("gpgme_data_seek");

332

perror("gpgme_data_seek");

421

333

plaintext_length = -1;

422

334

goto decrypt_end;

423

335

}

425

337

*plaintext = NULL;

426

338

while(true){

427

339

plaintext_capacity = incbuffer(plaintext,

428

(size_t)plaintext_length,

429

plaintext_capacity);

340

(size_t)plaintext_length,

341

plaintext_capacity);

430

342

if(plaintext_capacity == 0){

431

perror_plus("incbuffer");

432

plaintext_length = -1;

433

goto decrypt_end;

343

perror("incbuffer");

344

plaintext_length = -1;

345

goto decrypt_end;

434

346

}

435

347

436

348

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

441

353

break;

442

354

}

443

355

if(ret < 0){

444

perror_plus("gpgme_data_read");

356

perror("gpgme_data_read");

445

357

plaintext_length = -1;

446

358

goto decrypt_end;

447

359

}

449

361

}

450

362

451

363

if(debug){

452

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

364

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

453

365

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

454

366

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

455

367

}

477

389

/* GnuTLS log function callback */

478

390

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

479

391

const char* string){

480

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

392

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

481

393

}

482

394

483

395

static int init_gnutls_global(const char *pubkeyfilename,

485

397

int ret;

486

398

487

399

if(debug){

488

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

400

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

489

401

}

490

402

491

403

ret = gnutls_global_init();

492

404

if(ret != GNUTLS_E_SUCCESS){

493

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

494

safer_gnutls_strerror(ret));

405

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

406

safer_gnutls_strerror(ret));

495

407

return -1;

496

408

}

497

409

504

416

}

505

417

506

418

/* OpenPGP credentials */

507

ret = gnutls_certificate_allocate_credentials(&mc.cred);

419

gnutls_certificate_allocate_credentials(&mc.cred);

508

420

if(ret != GNUTLS_E_SUCCESS){

509

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

510

safer_gnutls_strerror(ret));

421

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

422

from

423

-Wunreachable-code

424

*/

425

safer_gnutls_strerror(ret));

511

426

gnutls_global_deinit();

512

427

return -1;

513

428

}

514

429

515

430

if(debug){

516

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

517

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

518

pubkeyfilename,

519

seckeyfilename);

431

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

432

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

433

seckeyfilename);

520

434

}

521

435

522

436

ret = gnutls_certificate_set_openpgp_key_file

523

437

(mc.cred, pubkeyfilename, seckeyfilename,

524

438

GNUTLS_OPENPGP_FMT_BASE64);

525

439

if(ret != GNUTLS_E_SUCCESS){

526

fprintf_plus(stderr,

527

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

528

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

529

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

530

safer_gnutls_strerror(ret));

440

fprintf(stderr,

441

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

442

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

443

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

444

safer_gnutls_strerror(ret));

531

445

goto globalfail;

532

446

}

533

447

534

448

/* GnuTLS server initialization */

535

449

ret = gnutls_dh_params_init(&mc.dh_params);

536

450

if(ret != GNUTLS_E_SUCCESS){

537

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

538

" initialization: %s\n",

539

safer_gnutls_strerror(ret));

451

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

452

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

540

453

goto globalfail;

541

454

}

542

455

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

543

456

if(ret != GNUTLS_E_SUCCESS){

544

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

545

safer_gnutls_strerror(ret));

457

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

458

safer_gnutls_strerror(ret));

546

459

goto globalfail;

547

460

}

548

461

563

476

/* GnuTLS session creation */

564

477

do {

565

478

ret = gnutls_init(session, GNUTLS_SERVER);

566

if(quit_now){

567

return -1;

568

}

569

479

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

570

480

if(ret != GNUTLS_E_SUCCESS){

571

fprintf_plus(stderr,

572

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

573

safer_gnutls_strerror(ret));

481

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

482

safer_gnutls_strerror(ret));

574

483

}

575

484

576

485

{

577

486

const char *err;

578

487

do {

579

488

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

580

if(quit_now){

581

gnutls_deinit(*session);

582

return -1;

583

}

584

489

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

585

490

if(ret != GNUTLS_E_SUCCESS){

586

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

587

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

588

safer_gnutls_strerror(ret));

491

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

492

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

493

safer_gnutls_strerror(ret));

589

494

gnutls_deinit(*session);

590

495

return -1;

591

496

}

594

499

do {

595

500

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

596

501

mc.cred);

597

if(quit_now){

598

gnutls_deinit(*session);

599

return -1;

600

}

601

502

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

602

503

if(ret != GNUTLS_E_SUCCESS){

603

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

604

safer_gnutls_strerror(ret));

504

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

505

safer_gnutls_strerror(ret));

605

506

gnutls_deinit(*session);

606

507

return -1;

607

508

}

618

519

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

619

520

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

620

521

522

sig_atomic_t quit_now = 0;

523

int signal_received = 0;

524

621

525

/* Called when a Mandos server is found */

622

526

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

623

527

AvahiIfIndex if_index,

629

533

struct sockaddr_in6 in6;

630

534

} to;

631

535

char *buffer = NULL;

632

char *decrypted_buffer = NULL;

536

char *decrypted_buffer;

633

537

size_t buffer_length = 0;

634

538

size_t buffer_capacity = 0;

635

539

size_t written;

636

int retval = -1;

540

int retval = 0;

637

541

gnutls_session_t session;

638

542

int pf; /* Protocol family */

639

543

640

errno = 0;

641

642

544

if(quit_now){

643

errno = EINTR;

644

545

return -1;

645

546

}

646

547

652

553

pf = PF_INET;

653

554

break;

654

555

default:

655

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

656

errno = EINVAL;

556

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

657

557

return -1;

658

558

}

659

559

663

563

}

664

564

665

565

if(debug){

666

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

667

PRIu16 "\n", ip, port);

566

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

567

"\n", ip, port);

668

568

}

669

569

670

570

tcp_sd = socket(pf, SOCK_STREAM, 0);

671

571

if(tcp_sd < 0){

672

int e = errno;

673

perror_plus("socket");

674

errno = e;

572

perror("socket");

573

retval = -1;

675

574

goto mandos_end;

676

575

}

677

576

678

577

if(quit_now){

679

errno = EINTR;

680

578

goto mandos_end;

681

579

}

682

580

689

587

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

690

588

}

691

589

if(ret < 0 ){

692

int e = errno;

693

perror_plus("inet_pton");

694

errno = e;

590

perror("inet_pton");

591

retval = -1;

695

592

goto mandos_end;

696

593

}

697

594

if(ret == 0){

698

int e = errno;

699

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

700

errno = e;

595

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

596

retval = -1;

701

597

goto mandos_end;

702

598

}

703

599

if(af == AF_INET6){

707

603

708

604

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

709

605

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

710

-Wunreachable-code*/

606

-Wunreachable-code*/

711

607

if(if_index == AVAHI_IF_UNSPEC){

712

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

713

" incomplete without a network interface\n");

714

errno = EINVAL;

608

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

609

" without a network interface\n");

610

retval = -1;

715

611

goto mandos_end;

716

612

}

717

613

/* Set the network interface number as scope */

724

620

}

725

621

726

622

if(quit_now){

727

errno = EINTR;

728

623

goto mandos_end;

729

624

}

730

625

732

627

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

733

628

char interface[IF_NAMESIZE];

734

629

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

735

perror_plus("if_indextoname");

630

perror("if_indextoname");

736

631

} else {

737

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

738

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

632

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

633

ip, interface, port);

739

634

}

740

635

} else {

741

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

742

ip, port);

636

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

637

port);

743

638

}

744

639

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

745

640

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

752

647

sizeof(addrstr));

753

648

}

754

649

if(pcret == NULL){

755

perror_plus("inet_ntop");

650

perror("inet_ntop");

756

651

} else {

757

652

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

758

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

653

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

759

654

}

760

655

}

761

656

}

762

657

763

658

if(quit_now){

764

errno = EINTR;

765

659

goto mandos_end;

766

660

}

767

661

771

665

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

772

666

}

773

667

if(ret < 0){

774

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

775

int e = errno;

776

perror_plus("connect");

777

errno = e;

778

}

668

perror("connect");

669

retval = -1;

779

670

goto mandos_end;

780

671

}

781

672

782

673

if(quit_now){

783

errno = EINTR;

784

674

goto mandos_end;

785

675

}

786

676

789

679

while(true){

790

680

size_t out_size = strlen(out);

791

681

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

792

out_size - written));

682

out_size - written));

793

683

if(ret == -1){

794

int e = errno;

795

perror_plus("write");

796

errno = e;

684

perror("write");

685

retval = -1;

797

686

goto mandos_end;

798

687

}

799

688

written += (size_t)ret;

809

698

}

810

699

811

700

if(quit_now){

812

errno = EINTR;

813

701

goto mandos_end;

814

702

}

815

703

}

816

704

817

705

if(debug){

818

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

706

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

819

707

}

820

708

821

709

if(quit_now){

822

errno = EINTR;

823

710

goto mandos_end;

824

711

}

825

712

826

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

827

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

828

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

829

gnutls_transport_set_ptr(session,

830

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

713

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

831

714

832

715

if(quit_now){

833

errno = EINTR;

834

716

goto mandos_end;

835

717

}

836

718

837

719

do {

838

720

ret = gnutls_handshake(session);

839

721

if(quit_now){

840

errno = EINTR;

841

722

goto mandos_end;

842

723

}

843

724

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

844

725

845

726

if(ret != GNUTLS_E_SUCCESS){

846

727

if(debug){

847

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

728

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

848

729

gnutls_perror(ret);

849

730

}

850

errno = EPROTO;

731

retval = -1;

851

732

goto mandos_end;

852

733

}

853

734

854

735

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

855

736

856

737

if(debug){

857

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

858

" %s\n", ip);

738

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

739

ip);

859

740

}

860

741

861

742

while(true){

862

743

863

744

if(quit_now){

864

errno = EINTR;

865

745

goto mandos_end;

866

746

}

867

747

868

748

buffer_capacity = incbuffer(&buffer, buffer_length,

869

buffer_capacity);

749

buffer_capacity);

870

750

if(buffer_capacity == 0){

871

int e = errno;

872

perror_plus("incbuffer");

873

errno = e;

751

perror("incbuffer");

752

retval = -1;

874

753

goto mandos_end;

875

754

}

876

755

877

756

if(quit_now){

878

errno = EINTR;

879

757

goto mandos_end;

880

758

}

881

759

894

772

ret = gnutls_handshake(session);

895

773

896

774

if(quit_now){

897

errno = EINTR;

898

775

goto mandos_end;

899

776

}

900

777

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

901

778

if(ret < 0){

902

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

903

"***\n");

779

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

904

780

gnutls_perror(ret);

905

errno = EPROTO;

781

retval = -1;

906

782

goto mandos_end;

907

783

}

908

784

break;

909

785

default:

910

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

911

" encrypted session with Mandos server\n");

786

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

787

" encrypted session with Mandos server\n");

788

retval = -1;

912

789

gnutls_bye(session, GNUTLS_SHUT_RDWR);

913

errno = EIO;

914

790

goto mandos_end;

915

791

}

916

792

} else {

919

795

}

920

796

921

797

if(debug){

922

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

923

}

924

925

if(quit_now){

926

errno = EINTR;

927

goto mandos_end;

928

}

929

930

do {

931

ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);

932

if(quit_now){

933

errno = EINTR;

934

goto mandos_end;

935

}

936

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

798

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

799

}

800

801

if(quit_now){

802

goto mandos_end;

803

}

804

805

gnutls_bye(session, GNUTLS_SHUT_RDWR);

806

807

if(quit_now){

808

goto mandos_end;

809

}

937

810

938

811

if(buffer_length > 0){

939

812

ssize_t decrypted_buffer_size;

940

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

813

decrypted_buffer_size = pgp_packet_decrypt(buffer,

814

buffer_length,

941

815

&decrypted_buffer);

942

816

if(decrypted_buffer_size >= 0){

943

817

944

818

written = 0;

945

819

while(written < (size_t) decrypted_buffer_size){

946

820

if(quit_now){

947

errno = EINTR;

948

821

goto mandos_end;

949

822

}

950

823

952

825

(size_t)decrypted_buffer_size - written,

953

826

stdout);

954

827

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

955

int e = errno;

956

828

if(debug){

957

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

958

strerror(errno));

829

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

830

strerror(errno));

959

831

}

960

errno = e;

961

goto mandos_end;

832

retval = -1;

833

break;

962

834

}

963

835

written += (size_t)ret;

964

836

}

965

retval = 0;

837

free(decrypted_buffer);

838

} else {

839

retval = -1;

966

840

}

841

} else {

842

retval = -1;

967

843

}

968

844

969

845

/* Shutdown procedure */

970

846

971

847

mandos_end:

972

{

973

int e = errno;

974

free(decrypted_buffer);

975

free(buffer);

976

if(tcp_sd >= 0){

977

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

978

}

979

if(ret == -1){

980

if(e == 0){

981

e = errno;

982

}

983

perror_plus("close");

984

}

985

gnutls_deinit(session);

986

errno = e;

987

if(quit_now){

988

errno = EINTR;

989

retval = -1;

990

}

848

free(buffer);

849

if(tcp_sd >= 0){

850

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

851

}

852

if(ret == -1){

853

perror("close");

854

}

855

gnutls_deinit(session);

856

if(quit_now){

857

retval = -1;

991

858

}

992

859

return retval;

993

860

}

1018

885

switch(event){

1019

886

default:

1020

887

case AVAHI_RESOLVER_FAILURE:

1021

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

1022

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

1023

domain,

1024

avahi_strerror(avahi_server_errno(mc.server)));

888

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

889

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

890

avahi_strerror(avahi_server_errno(mc.server)));

1025

891

break;

1026

892

1027

893

case AVAHI_RESOLVER_FOUND:

1029

895

char ip[AVAHI_ADDRESS_STR_MAX];

1030

896

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

1031

897

if(debug){

1032

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

1033

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

1034

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

898

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

899

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

900

ip, (intmax_t)interface, port);

1035

901

}

1036

902

int ret = start_mandos_communication(ip, port, interface,

1037

903

avahi_proto_to_af(proto));

1038

904

if(ret == 0){

1039

905

avahi_simple_poll_quit(mc.simple_poll);

1040

} else {

1041

if(not add_server(ip, port, interface,

1042

avahi_proto_to_af(proto))){

1043

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

1044

" list\n", name);

1045

}

1046

906

}

1047

907

}

1048

908

}

1072

932

default:

1073

933

case AVAHI_BROWSER_FAILURE:

1074

934

1075

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

1076

avahi_strerror(avahi_server_errno(mc.server)));

935

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

936

avahi_strerror(avahi_server_errno(mc.server)));

1077

937

avahi_simple_poll_quit(mc.simple_poll);

1078

938

return;

1079

939

1086

946

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

1087

947

name, type, domain, protocol, 0,

1088

948

resolve_callback, NULL) == NULL)

1089

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

1090

" %s\n", name,

1091

avahi_strerror(avahi_server_errno(mc.server)));

949

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

950

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

1092

951

break;

1093

952

1094

953

case AVAHI_BROWSER_REMOVE:

1097

956

case AVAHI_BROWSER_ALL_FOR_NOW:

1098

957

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1099

958

if(debug){

1100

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

1101

" searching...\n");

959

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

1102

960

}

1103

961

break;

1104

962

}

1105

963

}

1106

964

1107

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

965

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

1108

966

static void handle_sigterm(int sig){

1109

967

if(quit_now){

1110

968

return;

1112

970

quit_now = 1;

1113

971

signal_received = sig;

1114

972

int old_errno = errno;

1115

/* set main loop to exit */

1116

973

if(mc.simple_poll != NULL){

1117

974

avahi_simple_poll_quit(mc.simple_poll);

1118

975

}

1119

976

errno = old_errno;

1120

977

}

1121

978

1122

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

1123

int ret;

1124

1125

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

1126

if(s < 0){

1127

perror_plus("socket");

1128

return false;

1129

}

1130

strcpy(ifr->ifr_name, ifname);

1131

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1132

if(ret == -1){

1133

if(debug){

1134

perror_plus("ioctl SIOCGIFFLAGS");

1135

}

1136

return false;

1137

}

1138

return true;

1139

}

1140

1141

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

1142

1143

/* Reject the loopback device */

1144

if(ifr->ifr_flags & IFF_LOOPBACK){

1145

if(debug){

1146

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

1147

ifname);

1148

}

1149

return false;

1150

}

1151

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

1152

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

1153

if(debug){

1154

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

1155

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

1156

}

1157

return true;

1158

}

1159

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

1160

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

1161

if(debug){

1162

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1163

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

1164

}

1165

return false;

1166

}

1167

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

1168

if(ifr->ifr_flags & IFF_NOARP){

1169

if(debug){

1170

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

1171

ifname);

1172

}

1173

return false;

1174

}

1175

1176

/* Accept this device */

1177

if(debug){

1178

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

1179

}

1180

return true;

1181

}

1182

1183

/*

1184

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

1185

* corresponds to an acceptable network device.

1186

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

1187

*/

1188

int good_interface(const struct dirent *if_entry){

1189

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

1190

return 0;

1191

}

1192

1193

struct ifreq ifr;

1194

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

1195

if(debug){

1196

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

1197

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

1198

}

1199

return 0;

1200

}

1201

1202

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

1203

return 0;

1204

}

1205

return 1;

1206

}

1207

1208

/*

1209

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

1210

* corresponds to an acceptable network device which is up.

1211

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

1212

*/

1213

int up_interface(const struct dirent *if_entry){

1214

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

1215

return 0;

1216

}

1217

1218

struct ifreq ifr;

1219

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

1220

if(debug){

1221

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

1222

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

1223

}

1224

return 0;

1225

}

1226

1227

/* Reject down interfaces */

1228

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

1229

if(debug){

1230

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

1231

if_entry->d_name);

1232

}

1233

return 0;

1234

}

1235

1236

/* Reject non-running interfaces */

1237

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

1238

if(debug){

1239

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

1240

if_entry->d_name);

1241

}

1242

return 0;

1243

}

1244

1245

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

1246

return 0;

1247

}

1248

return 1;

1249

}

1250

1251

int notdotentries(const struct dirent *direntry){

1252

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

1253

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

1254

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

1255

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

1256

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

1257

return 0;

1258

}

1259

return 1;

1260

}

1261

1262

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

1263

int runnable_hook(const struct dirent *direntry){

1264

int ret;

1265

size_t sret;

1266

struct stat st;

1267

1268

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

1269

/* Empty name? */

1270

return 0;

1271

}

1272

1273

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

1274

"abcdefghijklmnopqrstuvwxyz"

1275

"0123456789"

1276

"_-");

1277

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

1278

/* Contains non-allowed characters */

1279

if(debug){

1280

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

1281

direntry->d_name);

1282

}

1283

return 0;

1284

}

1285

1286

char *fullname = NULL;

1287

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

1288

if(ret < 0){

1289

perror_plus("asprintf");

1290

return 0;

1291

}

1292

1293

ret = stat(fullname, &st);

1294

if(ret == -1){

1295

if(debug){

1296

perror_plus("Could not stat hook");

1297

}

1298

return 0;

1299

}

1300

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

1301

/* Not a regular file */

1302

if(debug){

1303

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

1304

direntry->d_name);

1305

}

1306

return 0;

1307

}

1308

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

1309

/* Not executable */

1310

if(debug){

1311

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

1312

direntry->d_name);

1313

}

1314

return 0;

1315

}

1316

if(debug){

1317

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

1318

direntry->d_name);

1319

}

1320

return 1;

1321

}

1322

1323

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1324

int ret;

1325

struct timespec now;

1326

struct timespec waited_time;

1327

intmax_t block_time;

1328

1329

while(true){

1330

if(mc.current_server == NULL){

1331

if (debug){

1332

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

1333

" No timeout!\n");

1334

}

1335

ret = avahi_simple_poll_iterate(s, -1);

1336

} else {

1337

if (debug){

1338

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

1339

" it, or wait\n");

1340

}

1341

/* the current time */

1342

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1343

if(ret == -1){

1344

perror_plus("clock_gettime");

1345

return -1;

1346

}

1347

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

1348

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

1349

waited_time.tv_sec = (now.tv_sec

1350

- mc.current_server->last_seen.tv_sec);

1351

waited_time.tv_nsec = (now.tv_nsec

1352

- mc.current_server->last_seen.tv_nsec);

1353

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

1354

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

1355

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

1356

block_time = ((retry_interval

1357

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

1358

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

1359

1360

if (debug){

1361

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

1362

block_time);

1363

}

1364

1365

if(block_time <= 0){

1366

ret = start_mandos_communication(mc.current_server->ip,

1367

mc.current_server->port,

1368

mc.current_server->if_index,

1369

mc.current_server->af);

1370

if(ret == 0){

1371

avahi_simple_poll_quit(mc.simple_poll);

1372

return 0;

1373

}

1374

ret = clock_gettime(CLOCK_MONOTONIC,

1375

&mc.current_server->last_seen);

1376

if(ret == -1){

1377

perror_plus("clock_gettime");

1378

return -1;

1379

}

1380

mc.current_server = mc.current_server->next;

1381

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

1382

servers, but don't block */

1383

}

1384

1385

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

1386

}

1387

if(ret != 0){

1388

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

1389

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

1390

}

1391

}

1392

}

1393

}

1394

1395

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

1396

int raise_privileges(void){

1397

int old_errno = errno;

1398

int ret_errno = 0;

1399

errno = 0;

1400

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

1401

perror_plus("seteuid");

1402

}

1403

ret_errno = errno;

1404

errno = old_errno;

1405

return ret_errno;

1406

}

1407

1408

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

1409

int raise_privileges_permanently(void){

1410

int old_errno = errno;

1411

int ret_errno = raise_privileges();

1412

if(ret_errno != 0){

1413

errno = old_errno;

1414

return ret_errno;

1415

}

1416

errno = 0;

1417

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

1418

perror_plus("seteuid");

1419

}

1420

ret_errno = errno;

1421

errno = old_errno;

1422

return ret_errno;

1423

}

1424

1425

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

1426

int lower_privileges(void){

1427

int old_errno = errno;

1428

int ret_errno = 0;

1429

errno = 0;

1430

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

1431

perror_plus("seteuid");

1432

}

1433

ret_errno = errno;

1434

errno = old_errno;

1435

return ret_errno;

1436

}

1437

1438

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

1439

const float delay){

1440

struct dirent **direntries;

1441

struct dirent *direntry;

1442

int ret;

1443

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

1444

alphasort);

1445

if(numhooks == -1){

1446

perror_plus("scandir");

1447

} else {

1448

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

1449

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

1450

direntry = direntries[i];

1451

char *fullname = NULL;

1452

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

1453

if(ret < 0){

1454

perror_plus("asprintf");

1455

continue;

1456

}

1457

if(debug){

1458

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

1459

direntry->d_name);

1460

}

1461

pid_t hook_pid = fork();

1462

if(hook_pid == 0){

1463

/* Child */

1464

/* Raise privileges */

1465

raise_privileges_permanently();

1466

/* Set group */

1467

errno = 0;

1468

ret = setgid(0);

1469

if(ret == -1){

1470

perror_plus("setgid");

1471

}

1472

/* Reset supplementary groups */

1473

errno = 0;

1474

ret = setgroups(0, NULL);

1475

if(ret == -1){

1476

perror_plus("setgroups");

1477

}

1478

dup2(devnull, STDIN_FILENO);

1479

close(devnull);

1480

dup2(STDERR_FILENO, STDOUT_FILENO);

1481

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

1482

if(ret == -1){

1483

perror_plus("setenv");

1484

_exit(EX_OSERR);

1485

}

1486

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

1487

if(ret == -1){

1488

perror_plus("setenv");

1489

_exit(EX_OSERR);

1490

}

1491

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

1492

if(ret == -1){

1493

perror_plus("setenv");

1494

_exit(EX_OSERR);

1495

}

1496

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

1497

if(ret == -1){

1498

perror_plus("setenv");

1499

_exit(EX_OSERR);

1500

}

1501

char *delaystring;

1502

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

1503

if(ret == -1){

1504

perror_plus("asprintf");

1505

_exit(EX_OSERR);

1506

}

1507

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

1508

if(ret == -1){

1509

free(delaystring);

1510

perror_plus("setenv");

1511

_exit(EX_OSERR);

1512

}

1513

free(delaystring);

1514

if(connect_to != NULL){

1515

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

1516

if(ret == -1){

1517

perror_plus("setenv");

1518

_exit(EX_OSERR);

1519

}

1520

}

1521

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

1522

perror_plus("execl");

1523

_exit(EXIT_FAILURE);

1524

}

1525

} else {

1526

int status;

1527

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

1528

perror_plus("waitpid");

1529

free(fullname);

1530

continue;

1531

}

1532

if(WIFEXITED(status)){

1533

if(WEXITSTATUS(status) != 0){

1534

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

1535

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

1536

WEXITSTATUS(status));

1537

free(fullname);

1538

continue;

1539

}

1540

} else if(WIFSIGNALED(status)){

1541

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

1542

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

1543

WTERMSIG(status));

1544

free(fullname);

1545

continue;

1546

} else {

1547

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

1548

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

1549

free(fullname);

1550

continue;

1551

}

1552

}

1553

free(fullname);

1554

if(debug){

1555

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

1556

direntry->d_name);

1557

}

1558

}

1559

close(devnull);

1560

}

1561

return true;

1562

}

1563

1564

int bring_up_interface(const char * const interface, const float delay){

1565

int sd = -1;

1566

int ret;

1567

struct ifreq network;

1568

AvahiIfIndex if_index = (AvahiIfIndex)if_nametoindex(interface);

1569

if(if_index == 0){

1570

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

1571

return EX_UNAVAILABLE;

1572

}

1573

1574

if(quit_now){

1575

return EINTR;

1576

}

1577

1578

/* Re-raise priviliges */

1579

raise_privileges();

1580

1581

#ifdef __linux__

1582

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1583

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

1584

ret = klogctl(8, NULL, 5);

1585

bool restore_loglevel = true;

1586

if(ret == -1){

1587

restore_loglevel = false;

1588

perror_plus("klogctl");

1589

}

1590

#endif /* __linux__ */

1591

1592

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1593

if(sd < 0){

1594

perror_plus("socket");

1595

#ifdef __linux__

1596

if(restore_loglevel){

1597

ret = klogctl(7, NULL, 0);

1598

if(ret == -1){

1599

perror_plus("klogctl");

1600

}

1601

}

1602

#endif /* __linux__ */

1603

/* Lower privileges */

1604

lower_privileges();

1605

return EX_OSERR;

1606

;

1607

}

1608

strcpy(network.ifr_name, interface);

1609

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

1610

if(ret == -1){

1611

perror_plus("ioctl SIOCGIFFLAGS");

1612

#ifdef __linux__

1613

if(restore_loglevel){

1614

ret = klogctl(7, NULL, 0);

1615

if(ret == -1){

1616

perror_plus("klogctl");

1617

}

1618

}

1619

#endif /* __linux__ */

1620

/* Lower privileges */

1621

lower_privileges();

1622

return EX_OSERR;

1623

}

1624

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

1625

network.ifr_flags |= IFF_UP;

1626

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

1627

if(ret == -1){

1628

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1629

#ifdef __linux__

1630

if(restore_loglevel){

1631

ret = klogctl(7, NULL, 0);

1632

if(ret == -1){

1633

perror_plus("klogctl");

1634

}

1635

}

1636

#endif /* __linux__ */

1637

/* Lower privileges */

1638

lower_privileges();

1639

return EX_OSERR;

1640

}

1641

}

1642

/* Sleep checking until interface is running.

1643

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

1644

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

1645

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

1646

if(ret == -1){

1647

perror_plus("ioctl SIOCGIFFLAGS");

1648

} else if(network.ifr_flags & IFF_RUNNING){

1649

break;

1650

}

1651

struct timespec sleeptime = { .tv_nsec = 250000000 };

1652

ret = nanosleep(&sleeptime, NULL);

1653

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

1654

perror_plus("nanosleep");

1655

}

1656

}

1657

/* Close the socket */

1658

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

1659

if(ret == -1){

1660

perror_plus("close");

1661

}

1662

#ifdef __linux__

1663

if(restore_loglevel){

1664

/* Restores kernel loglevel to default */

1665

ret = klogctl(7, NULL, 0);

1666

if(ret == -1){

1667

perror_plus("klogctl");

1668

}

1669

}

1670

#endif /* __linux__ */

1671

/* Lower privileges */

1672

lower_privileges();

1673

return errno;

1674

}

1675

1676

979

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

1677

980

AvahiSServiceBrowser *sb = NULL;

1678

981

int error;

1680

983

intmax_t tmpmax;

1681

984

char *tmp;

1682

985

int exitcode = EXIT_SUCCESS;

1683

const char *interface = "";

986

const char *interface = "eth0";

1684

987

struct ifreq network;

1685

988

int sd = -1;

1686

989

bool take_down_interface = false;

990

uid_t uid;

991

gid_t gid;

992

char *connect_to = NULL;

1687

993

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

1688

994

bool tempdir_created = false;

1689

995

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1693

999

bool gnutls_initialized = false;

1694

1000

bool gpgme_initialized = false;

1695

1001

float delay = 2.5f;

1696

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

1697

retrying the same server again */

1698

1002

1699

1003

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1700

1004

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1706

1010

errno = 0;

1707

1011

ret = setgid(gid);

1708

1012

if(ret == -1){

1709

perror_plus("setgid");

1013

perror("setgid");

1710

1014

}

1711

1015

1712

1016

/* Lower user privileges (temporarily) */

1713

1017

errno = 0;

1714

1018

ret = seteuid(uid);

1715

1019

if(ret == -1){

1716

perror_plus("seteuid");

1020

perror("seteuid");

1717

1021

}

1718

1022

1719

1023

if(quit_now){

1754

1058

.arg = "SECONDS",

1755

1059

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

1756

1060

.group = 2 },

1757

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

1758

.arg = "SECONDS",

1759

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

1760

.group = 2 },

1761

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

1762

.arg = "DIR",

1763

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

1764

.group = 2 },

1765

/*

1766

* These reproduce what we would get without ARGP_NO_HELP

1767

*/

1768

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

1769

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

1770

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

1771

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

1772

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

1773

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

1774

1061

{ .name = NULL }

1775

1062

};

1776

1063

1777

1064

error_t parse_opt(int key, char *arg,

1778

1065

struct argp_state *state){

1779

errno = 0;

1780

1066

switch(key){

1781

1067

case 128: /* --debug */

1782

1068

debug = true;

1798

1084

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

1799

1085

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

1800

1086

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

1801

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

1087

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

1088

exit(EXIT_FAILURE);

1802

1089

}

1803

1090

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

1804

1091

break;

1809

1096

errno = 0;

1810

1097

delay = strtof(arg, &tmp);

1811

1098

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

1812

argp_error(state, "Bad delay");

1813

}

1814

case 132: /* --retry */

1815

errno = 0;

1816

retry_interval = strtod(arg, &tmp);

1817

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

1818

or (retry_interval * 1000) > INT_MAX

1819

or retry_interval < 0){

1820

argp_error(state, "Bad retry interval");

1821

}

1822

break;

1823

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

1824

hookdir = arg;

1825

break;

1826

/*

1827

* These reproduce what we would get without ARGP_NO_HELP

1828

*/

1829

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

1830

argp_state_help(state, state->out_stream,

1831

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

1832

& ~(unsigned int)ARGP_HELP_EXIT_OK);

1833

case -3: /* --usage */

1834

argp_state_help(state, state->out_stream,

1835

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1836

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

1837

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

1838

exit(argp_err_exit_status);

1099

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

1100

exit(EXIT_FAILURE);

1101

}

1102

break;

1103

case ARGP_KEY_ARG:

1104

argp_usage(state);

1105

case ARGP_KEY_END:

1839

1106

break;

1840

1107

default:

1841

1108

return ARGP_ERR_UNKNOWN;

1842

1109

}

1843

return errno;

1110

return 0;

1844

1111

}

1845

1112

1846

1113

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

1847

1114

.args_doc = "",

1848

1115

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

1849

1116

" passwords from a Mandos server" };

1850

ret = argp_parse(&argp, argc, argv,

1851

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1852

switch(ret){

1853

case 0:

1854

break;

1855

case ENOMEM:

1856

default:

1857

errno = ret;

1858

perror_plus("argp_parse");

1859

exitcode = EX_OSERR;

1860

goto end;

1861

case EINVAL:

1862

exitcode = EX_USAGE;

1863

goto end;

1864

}

1865

}

1866

1867

{

1868

/* Work around Debian bug #633582:

1869

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

1870

1871

/* Re-raise priviliges */

1872

if(raise_privileges() == 0){

1873

struct stat st;

1874

1875

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

1876

int seckey_fd = open(seckey, O_RDONLY);

1877

if(seckey_fd == -1){

1878

perror_plus("open");

1879

} else {

1880

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

1881

if(ret == -1){

1882

perror_plus("fstat");

1883

} else {

1884

if(S_ISREG(st.st_mode)

1885

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

1886

ret = fchown(seckey_fd, uid, gid);

1887

if(ret == -1){

1888

perror_plus("fchown");

1889

}

1890

}

1891

}

1892

TEMP_FAILURE_RETRY(close(seckey_fd));

1893

}

1894

}

1895

1896

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

1897

int pubkey_fd = open(pubkey, O_RDONLY);

1898

if(pubkey_fd == -1){

1899

perror_plus("open");

1900

} else {

1901

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

1902

if(ret == -1){

1903

perror_plus("fstat");

1904

} else {

1905

if(S_ISREG(st.st_mode)

1906

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

1907

ret = fchown(pubkey_fd, uid, gid);

1908

if(ret == -1){

1909

perror_plus("fchown");

1910

}

1911

}

1912

}

1913

TEMP_FAILURE_RETRY(close(pubkey_fd));

1914

}

1915

}

1916

1917

/* Lower privileges */

1918

errno = 0;

1919

ret = seteuid(uid);

1920

if(ret == -1){

1921

perror_plus("seteuid");

1922

}

1923

}

1924

}

1925

1926

/* Run network hooks */

1927

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

1928

goto end;

1117

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

1118

if(ret == ARGP_ERR_UNKNOWN){

1119

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

1120

exitcode = EXIT_FAILURE;

1121

goto end;

1122

}

1929

1123

}

1930

1124

1931

1125

if(not debug){

1932

1126

avahi_set_log_function(empty_log);

1933

1127

}

1934

1128

1935

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

1936

struct dirent **direntries;

1937

/* First look for interfaces that are up */

1938

ret = scandir(sys_class_net, &direntries, up_interface,

1939

alphasort);

1940

if(ret == 0){

1941

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

1942

free(direntries);

1943

ret = scandir(sys_class_net, &direntries, good_interface,

1944

alphasort);

1945

}

1946

if(ret >= 1){

1947

/* Pick the first interface returned */

1948

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

1949

if(debug){

1950

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

1951

}

1952

if(interface == NULL){

1953

perror_plus("malloc");

1954

free(direntries);

1955

exitcode = EXIT_FAILURE;

1956

goto end;

1957

}

1958

free(direntries);

1959

} else {

1960

free(direntries);

1961

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

1962

exitcode = EXIT_FAILURE;

1963

goto end;

1964

}

1965

}

1966

1967

1129

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

1968

1130

from the signal handler */

1969

1131

/* Initialize the pseudo-RNG for Avahi */

1970

1132

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

1971

1133

mc.simple_poll = avahi_simple_poll_new();

1972

1134

if(mc.simple_poll == NULL){

1973

fprintf_plus(stderr,

1974

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

1975

exitcode = EX_UNAVAILABLE;

1135

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

1136

exitcode = EXIT_FAILURE;

1976

1137

goto end;

1977

1138

}

1978

1139

1979

1140

sigemptyset(&sigterm_action.sa_mask);

1980

1141

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

1981

1142

if(ret == -1){

1982

perror_plus("sigaddset");

1983

exitcode = EX_OSERR;

1143

perror("sigaddset");

1144

exitcode = EXIT_FAILURE;

1984

1145

goto end;

1985

1146

}

1986

1147

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

1987

1148

if(ret == -1){

1988

perror_plus("sigaddset");

1989

exitcode = EX_OSERR;

1149

perror("sigaddset");

1150

exitcode = EXIT_FAILURE;

1990

1151

goto end;

1991

1152

}

1992

1153

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

1993

1154

if(ret == -1){

1994

perror_plus("sigaddset");

1995

exitcode = EX_OSERR;

1155

perror("sigaddset");

1156

exitcode = EXIT_FAILURE;

1996

1157

goto end;

1997

1158

}

1998

1159

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

2001

1162

*/

2002

1163

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

2003

1164

if(ret == -1){

2004

perror_plus("sigaction");

2005

return EX_OSERR;

1165

perror("sigaction");

1166

return EXIT_FAILURE;

2006

1167

}

2007

1168

if(old_sigterm_action.sa_handler != SIG_IGN){

2008

1169

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

2009

1170

if(ret == -1){

2010

perror_plus("sigaction");

2011

exitcode = EX_OSERR;

1171

perror("sigaction");

1172

exitcode = EXIT_FAILURE;

2012

1173

goto end;

2013

1174

}

2014

1175

}

2015

1176

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

2016

1177

if(ret == -1){

2017

perror_plus("sigaction");

2018

return EX_OSERR;

1178

perror("sigaction");

1179

return EXIT_FAILURE;

2019

1180

}

2020

1181

if(old_sigterm_action.sa_handler != SIG_IGN){

2021

1182

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

2022

1183

if(ret == -1){

2023

perror_plus("sigaction");

2024

exitcode = EX_OSERR;

1184

perror("sigaction");

1185

exitcode = EXIT_FAILURE;

2025

1186

goto end;

2026

1187

}

2027

1188

}

2028

1189

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

2029

1190

if(ret == -1){

2030

perror_plus("sigaction");

2031

return EX_OSERR;

1191

perror("sigaction");

1192

return EXIT_FAILURE;

2032

1193

}

2033

1194

if(old_sigterm_action.sa_handler != SIG_IGN){

2034

1195

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

2035

1196

if(ret == -1){

2036

perror_plus("sigaction");

2037

exitcode = EX_OSERR;

1197

perror("sigaction");

1198

exitcode = EXIT_FAILURE;

2038

1199

goto end;

2039

1200

}

2040

1201

}

2041

1202

2042

1203

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

2043

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

2044

ret = bring_up_interface(interface, delay);

2045

if(ret){

2046

errno = ret;

2047

perror_plus("Failed to bring up interface");

1204

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

1205

if_index = (AvahiIfIndex) if_nametoindex(interface);

1206

if(if_index == 0){

1207

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

1208

exitcode = EXIT_FAILURE;

1209

goto end;

1210

}

1211

1212

if(quit_now){

1213

goto end;

1214

}

1215

1216

/* Re-raise priviliges */

1217

errno = 0;

1218

ret = seteuid(0);

1219

if(ret == -1){

1220

perror("seteuid");

1221

}

1222

1223

#ifdef __linux__

1224

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1225

messages to mess up the prompt */

1226

ret = klogctl(8, NULL, 5);

1227

bool restore_loglevel = true;

1228

if(ret == -1){

1229

restore_loglevel = false;

1230

perror("klogctl");

1231

}

1232

#endif /* __linux__ */

1233

1234

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1235

if(sd < 0){

1236

perror("socket");

1237

exitcode = EXIT_FAILURE;

1238

#ifdef __linux__

1239

if(restore_loglevel){

1240

ret = klogctl(7, NULL, 0);

1241

if(ret == -1){

1242

perror("klogctl");

1243

}

1244

}

1245

#endif /* __linux__ */

1246

/* Lower privileges */

1247

errno = 0;

1248

ret = seteuid(uid);

1249

if(ret == -1){

1250

perror("seteuid");

1251

}

1252

goto end;

1253

}

1254

strcpy(network.ifr_name, interface);

1255

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

1256

if(ret == -1){

1257

perror("ioctl SIOCGIFFLAGS");

1258

#ifdef __linux__

1259

if(restore_loglevel){

1260

ret = klogctl(7, NULL, 0);

1261

if(ret == -1){

1262

perror("klogctl");

1263

}

1264

}

1265

#endif /* __linux__ */

1266

exitcode = EXIT_FAILURE;

1267

/* Lower privileges */

1268

errno = 0;

1269

ret = seteuid(uid);

1270

if(ret == -1){

1271

perror("seteuid");

1272

}

1273

goto end;

1274

}

1275

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

1276

network.ifr_flags |= IFF_UP;

1277

take_down_interface = true;

1278

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

1279

if(ret == -1){

1280

take_down_interface = false;

1281

perror("ioctl SIOCSIFFLAGS");

1282

exitcode = EXIT_FAILURE;

1283

#ifdef __linux__

1284

if(restore_loglevel){

1285

ret = klogctl(7, NULL, 0);

1286

if(ret == -1){

1287

perror("klogctl");

1288

}

1289

}

1290

#endif /* __linux__ */

1291

/* Lower privileges */

1292

errno = 0;

1293

ret = seteuid(uid);

1294

if(ret == -1){

1295

perror("seteuid");

1296

}

1297

goto end;

1298

}

1299

}

1300

/* sleep checking until interface is running */

1301

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

1302

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

1303

if(ret == -1){

1304

perror("ioctl SIOCGIFFLAGS");

1305

} else if(network.ifr_flags & IFF_RUNNING){

1306

break;

1307

}

1308

struct timespec sleeptime = { .tv_nsec = 250000000 };

1309

ret = nanosleep(&sleeptime, NULL);

1310

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

1311

perror("nanosleep");

1312

}

1313

}

1314

if(not take_down_interface){

1315

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

1316

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

1317

if(ret == -1){

1318

perror("close");

1319

}

1320

}

1321

#ifdef __linux__

1322

if(restore_loglevel){

1323

/* Restores kernel loglevel to default */

1324

ret = klogctl(7, NULL, 0);

1325

if(ret == -1){

1326

perror("klogctl");

1327

}

1328

}

1329

#endif /* __linux__ */

1330

/* Lower privileges */

1331

errno = 0;

1332

if(take_down_interface){

1333

/* Lower privileges */

1334

ret = seteuid(uid);

1335

if(ret == -1){

1336

perror("seteuid");

1337

}

1338

} else {

1339

/* Lower privileges permanently */

1340

ret = setuid(uid);

1341

if(ret == -1){

1342

perror("setuid");

1343

}

2048

1344

}

2049

1345

}

2050

1346

2054

1350

2055

1351

ret = init_gnutls_global(pubkey, seckey);

2056

1352

if(ret == -1){

2057

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

2058

exitcode = EX_UNAVAILABLE;

1353

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

1354

exitcode = EXIT_FAILURE;

2059

1355

goto end;

2060

1356

} else {

2061

1357

gnutls_initialized = true;

2065

1361

goto end;

2066

1362

}

2067

1363

1364

tempdir_created = true;

2068

1365

if(mkdtemp(tempdir) == NULL){

2069

perror_plus("mkdtemp");

1366

tempdir_created = false;

1367

perror("mkdtemp");

2070

1368

goto end;

2071

1369

}

2072

tempdir_created = true;

2073

1370

2074

1371

if(quit_now){

2075

1372

goto end;

2076

1373

}

2077

1374

2078

1375

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

2079

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

2080

exitcode = EX_UNAVAILABLE;

1376

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

1377

exitcode = EXIT_FAILURE;

2081

1378

goto end;

2082

1379

} else {

2083

1380

gpgme_initialized = true;

2091

1388

/* Connect directly, do not use Zeroconf */

2092

1389

/* (Mainly meant for debugging) */

2093

1390

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

2094

2095

1391

if(address == NULL){

2096

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

2097

exitcode = EX_USAGE;

1392

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

1393

exitcode = EXIT_FAILURE;

2098

1394

goto end;

2099

1395

}

2100

1396

2107

1403

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

2108

1404

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

2109

1405

or tmpmax != (uint16_t)tmpmax){

2110

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

2111

exitcode = EX_USAGE;

1406

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

1407

exitcode = EXIT_FAILURE;

2112

1408

goto end;

2113

1409

}

2114

1410

2118

1414

2119

1415

port = (uint16_t)tmpmax;

2120

1416

*address = '\0';

1417

address = connect_to;

2121

1418

/* Colon in address indicates IPv6 */

2122

1419

int af;

2123

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

1420

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

2124

1421

af = AF_INET6;

2125

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

2126

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

2127

{

2128

connect_to++;

2129

address[-1] = '\0';

2130

}

2131

1422

} else {

2132

1423

af = AF_INET;

2133

1424

}

2134

address = connect_to;

2135

1425

2136

1426

if(quit_now){

2137

1427

goto end;

2138

1428

}

2139

1429

2140

while(not quit_now){

2141

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

2142

if(quit_now or ret == 0){

2143

break;

2144

}

2145

if(debug){

2146

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

2147

(int)retry_interval);

2148

}

2149

sleep((int)retry_interval);

2150

}

2151

2152

if (not quit_now){

1430

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

1431

if(ret < 0){

1432

exitcode = EXIT_FAILURE;

1433

} else {

2153

1434

exitcode = EXIT_SUCCESS;

2154

1435

}

2155

2156

1436

goto end;

2157

1437

}

2158

1438

2180

1460

2181

1461

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

2182

1462

if(mc.server == NULL){

2183

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

2184

avahi_strerror(error));

2185

exitcode = EX_UNAVAILABLE;

1463

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

1464

avahi_strerror(error));

1465

exitcode = EXIT_FAILURE;

2186

1466

goto end;

2187

1467

}

2188

1468

2195

1475

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2196

1476

NULL, 0, browse_callback, NULL);

2197

1477

if(sb == NULL){

2198

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

2199

avahi_strerror(avahi_server_errno(mc.server)));

2200

exitcode = EX_UNAVAILABLE;

1478

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

1479

avahi_strerror(avahi_server_errno(mc.server)));

1480

exitcode = EXIT_FAILURE;

2201

1481

goto end;

2202

1482

}

2203

1483

2208

1488

/* Run the main loop */

2209

1489

2210

1490

if(debug){

2211

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

2212

}

2213

2214

ret = avahi_loop_with_timeout(mc.simple_poll,

2215

(int)(retry_interval * 1000));

2216

if(debug){

2217

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

2218

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

2219

}

1491

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

1492

}

1493

1494

avahi_simple_poll_loop(mc.simple_poll);

2220

1495

2221

1496

end:

2222

1497

2223

1498

if(debug){

2224

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

1499

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

2225

1500

}

2226

1501

2227

1502

/* Cleanup things */

2244

1519

gpgme_release(mc.ctx);

2245

1520

}

2246

1521

2247

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

2248

has seen */

2249

if(mc.current_server != NULL){

2250

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

2251

while(mc.current_server != NULL){

2252

server *next = mc.current_server->next;

2253

free(mc.current_server);

2254

mc.current_server = next;

1522

/* Take down the network interface */

1523

if(take_down_interface){

1524

/* Re-raise priviliges */

1525

errno = 0;

1526

ret = seteuid(0);

1527

if(ret == -1){

1528

perror("seteuid");

2255

1529

}

2256

}

2257

2258

/* Run network hooks */

2259

run_network_hooks("stop", interface, delay);

2260

2261

/* Re-raise priviliges */

2262

{

2263

raise_privileges();

2264

2265

/* Take down the network interface */

2266

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

1530

if(geteuid() == 0){

2267

1531

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

2268

1532

if(ret == -1){

2269

perror_plus("ioctl SIOCGIFFLAGS");

2270

} else if(network.ifr_flags & IFF_UP){

2271

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

1533

perror("ioctl SIOCGIFFLAGS");

1534

} else if(network.ifr_flags & IFF_UP) {

1535

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

2272

1536

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

2273

1537

if(ret == -1){

2274

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1538

perror("ioctl SIOCSIFFLAGS");

2275

1539

}

2276

1540

}

2277

1541

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

2278

1542

if(ret == -1){

2279

perror_plus("close");

1543

perror("close");

1544

}

1545

/* Lower privileges permanently */

1546

errno = 0;

1547

ret = setuid(uid);

1548

if(ret == -1){

1549

perror("setuid");

2280

1550

}

2281

1551

}

2282

1552

}

2283

/* Lower privileges permanently */

2284

errno = 0;

2285

ret = setuid(uid);

2286

if(ret == -1){

2287

perror_plus("setuid");

2288

}

2289

1553

2290

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

1554

/* Removes the temp directory used by GPGME */

2291

1555

if(tempdir_created){

2292

struct dirent **direntries = NULL;

2293

struct dirent *direntry = NULL;

2294

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

2295

alphasort);

2296

if (numentries > 0){

2297

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

2298

direntry = direntries[i];

1556

DIR *d;

1557

struct dirent *direntry;

1558

d = opendir(tempdir);

1559

if(d == NULL){

1560

if(errno != ENOENT){

1561

perror("opendir");

1562

}

1563

} else {

1564

while(true){

1565

direntry = readdir(d);

1566

if(direntry == NULL){

1567

break;

1568

}

1569

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

1570

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

1571

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

1572

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

1573

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

1574

continue;

1575

}

2299

1576

char *fullname = NULL;

2300

1577

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

2301

1578

direntry->d_name);

2302

1579

if(ret < 0){

2303

perror_plus("asprintf");

1580

perror("asprintf");

2304

1581

continue;

2305

1582

}

2306

1583

ret = remove(fullname);

2307

1584

if(ret == -1){

2308

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

2309

strerror(errno));

1585

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

1586

strerror(errno));

2310

1587

}

2311

1588

free(fullname);

2312

1589

}

2313

}

2314

2315

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

2316

free(direntries);

2317

if (numentries == -1){

2318

perror_plus("scandir");

1590

closedir(d);

2319

1591

}

2320

1592

ret = rmdir(tempdir);

2321

1593

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

2322

perror_plus("rmdir");

1594

perror("rmdir");

2323

1595

}

2324

1596

}

2325

1597

2326

1598

if(quit_now){

2327

1599

sigemptyset(&old_sigterm_action.sa_mask);

2328

1600

old_sigterm_action.sa_handler = SIG_DFL;

2329

ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,

2330

&old_sigterm_action,

2331

NULL));

1601

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

2332

1602

if(ret == -1){

2333

perror_plus("sigaction");

2334

}

2335

do {

2336

ret = raise(signal_received);

2337

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

2338

if(ret != 0){

2339

perror_plus("raise");

2340

abort();

2341

}

2342

TEMP_FAILURE_RETRY(pause());

1603

perror("sigaction");

1604

}

1605

raise(signal_received);

2343

1606

}

2344

1607

2345

1608

return exitcode;