/mandos/trunk : revision 463.1.9

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

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*

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* Everything else is

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*

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

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

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* along with this program. If not, see

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

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*

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

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

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*/

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

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#ifndef _LARGEFILE_SOURCE

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#define _LARGEFILE_SOURCE

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#endif /* not _LARGEFILE_SOURCE */

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#endif

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#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

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#endif /* not _FILE_OFFSET_BITS */

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#endif

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

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

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stdout, ferror() */

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

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stdout, ferror(), remove() */

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

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

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

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strtof(), abort() */

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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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getnameinfo() */

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

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inet_pton(), connect() */

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

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

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*/

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

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strtoimax() */

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

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program_invocation_short_name */

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

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

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

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unlinkat() */

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

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setgid(), pause() */

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

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EAI_SYSTEM, gai_strerror() */

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#ifdef __linux__

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

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init_gnutls_session(),

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108

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

133

122

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

134

123

#define SECKEY "seckey.txt"

135

124

#define PUBKEY "pubkey.txt"

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

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125

138

126

bool debug = false;

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127

static const char mandos_protocol_version[] = "1";

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

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

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

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

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char *connect_to = NULL;

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const char *hookdir = HOOKDIR;

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int hookdir_fd = -1;

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uid_t uid = 65534;

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gid_t gid = 65534;

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149

/* 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 */

161

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typedef struct {

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AvahiSimplePoll *simple_poll;

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AvahiServer *server;

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gnutls_certificate_credentials_t cred;

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unsigned int dh_bits;

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gnutls_dh_params_t dh_params;

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140

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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142

} mandos_context;

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143

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/* global so signal handler can reach it*/

174

AvahiSimplePoll *simple_poll;

144

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

145

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" };

175

148

176

149

sig_atomic_t quit_now = 0;

177

150

int signal_received = 0;

178

151

179

/* Function to use when printing errors */

180

void perror_plus(const char *print_text){

181

int e = errno;

182

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

183

program_invocation_short_name);

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errno = e;

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perror(print_text);

186

}

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188

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

189

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

190

va_list ap;

191

va_start (ap, format);

192

193

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

194

program_invocation_short_name));

195

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

196

}

197

198

152

/*

199

153

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

200

154

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

201

155

* "buffer_length" is how much is already used.

202

156

*/

203

__attribute__((nonnull, warn_unused_result))

204

157

size_t incbuffer(char **buffer, size_t buffer_length,

205

size_t buffer_capacity){

158

size_t buffer_capacity){

206

159

if(buffer_length + BUFFER_SIZE > buffer_capacity){

207

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

208

if(new_buf == NULL){

209

int old_errno = errno;

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free(*buffer);

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errno = old_errno;

212

*buffer = NULL;

160

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

161

if(buffer == NULL){

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162

return 0;

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163

}

215

*buffer = new_buf;

216

164

buffer_capacity += BUFFER_SIZE;

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165

}

218

166

return buffer_capacity;

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167

}

220

168

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

222

__attribute__((nonnull, warn_unused_result))

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

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int af, server **current_server){

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int ret;

226

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

227

if(new_server == NULL){

228

perror_plus("malloc");

229

return false;

230

}

231

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

232

.port = port,

233

.if_index = if_index,

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.af = af };

235

if(new_server->ip == NULL){

236

perror_plus("strdup");

237

free(new_server);

238

return false;

239

}

240

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

241

if(ret == -1){

242

perror_plus("clock_gettime");

243

#ifdef __GNUC__

244

#pragma GCC diagnostic push

245

#pragma GCC diagnostic ignored "-Wcast-qual"

246

#endif

247

free((char *)(new_server->ip));

248

#ifdef __GNUC__

249

#pragma GCC diagnostic pop

250

#endif

251

free(new_server);

252

return false;

253

}

254

/* Special case of first server */

255

if(*current_server == NULL){

256

new_server->next = new_server;

257

new_server->prev = new_server;

258

*current_server = new_server;

259

} else {

260

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

261

new_server->next = *current_server;

262

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

263

new_server->prev->next = new_server;

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(*current_server)->prev = new_server;

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}

266

return true;

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}

268

269

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/*

270

170

* Initialize GPGME.

271

171

*/

272

__attribute__((nonnull, warn_unused_result))

273

static bool init_gpgme(const char * const seckey,

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const char * const pubkey,

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const char * const tempdir,

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mandos_context *mc){

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static bool init_gpgme(const char *seckey,

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const char *pubkey, const char *tempdir){

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gpgme_error_t rc;

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gpgme_engine_info_t engine_info;

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177

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/*

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

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180

*/

283

bool import_key(const char * const filename){

181

bool import_key(const char *filename){

284

182

int ret;

285

183

int fd;

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184

gpgme_data_t pgp_data;

287

185

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

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187

if(fd == -1){

290

perror_plus("open");

188

perror("open");

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189

return false;

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190

}

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rc = gpgme_data_new_from_fd(&pgp_data, fd);

295

193

if(rc != GPG_ERR_NO_ERROR){

296

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

299

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}

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

199

rc = gpgme_op_import(mc.ctx, pgp_data);

302

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if(rc != GPG_ERR_NO_ERROR){

303

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

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gpgme_strsource(rc), gpgme_strerror(rc));

201

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

306

204

}

307

205

308

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

309

207

if(ret == -1){

310

perror_plus("close");

208

perror("close");

311

209

}

312

210

gpgme_data_release(pgp_data);

313

211

return true;

314

212

}

315

213

316

214

if(debug){

317

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

215

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

318

216

}

319

217

320

218

/* Init GPGME */

321

219

gpgme_check_version(NULL);

322

220

rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

323

221

if(rc != GPG_ERR_NO_ERROR){

324

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

325

gpgme_strsource(rc), gpgme_strerror(rc));

222

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

223

gpgme_strsource(rc), gpgme_strerror(rc));

326

224

return false;

327

225

}

328

226

329

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

227

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

330

228

rc = gpgme_get_engine_info(&engine_info);

331

229

if(rc != GPG_ERR_NO_ERROR){

332

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

333

gpgme_strsource(rc), gpgme_strerror(rc));

230

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

231

gpgme_strsource(rc), gpgme_strerror(rc));

334

232

return false;

335

233

}

336

234

while(engine_info != NULL){

342

240

engine_info = engine_info->next;

343

241

}

344

242

if(engine_info == NULL){

345

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

346

tempdir);

243

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

347

244

return false;

348

245

}

349

246

350

247

/* Create new GPGME "context" */

351

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

248

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

352

249

if(rc != GPG_ERR_NO_ERROR){

353

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

354

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

355

gpgme_strerror(rc));

250

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

251

gpgme_strsource(rc), gpgme_strerror(rc));

356

252

return false;

357

253

}

358

254

367

263

* Decrypt OpenPGP data.

368

264

* Returns -1 on error

369

265

*/

370

__attribute__((nonnull, warn_unused_result))

371

266

static ssize_t pgp_packet_decrypt(const char *cryptotext,

372

267

size_t crypto_size,

373

char **plaintext,

374

mandos_context *mc){

268

char **plaintext){

375

269

gpgme_data_t dh_crypto, dh_plain;

376

270

gpgme_error_t rc;

377

271

ssize_t ret;

379

273

ssize_t plaintext_length = 0;

380

274

381

275

if(debug){

382

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

276

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

383

277

}

384

278

385

279

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

386

280

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

387

281

0);

388

282

if(rc != GPG_ERR_NO_ERROR){

389

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

390

gpgme_strsource(rc), gpgme_strerror(rc));

283

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

284

gpgme_strsource(rc), gpgme_strerror(rc));

391

285

return -1;

392

286

}

393

287

394

288

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

395

289

rc = gpgme_data_new(&dh_plain);

396

290

if(rc != GPG_ERR_NO_ERROR){

397

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

398

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

399

gpgme_strsource(rc), gpgme_strerror(rc));

291

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

292

gpgme_strsource(rc), gpgme_strerror(rc));

400

293

gpgme_data_release(dh_crypto);

401

294

return -1;

402

295

}

403

296

404

297

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

405

298

data buffer */

406

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

299

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

407

300

if(rc != GPG_ERR_NO_ERROR){

408

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

409

gpgme_strsource(rc), gpgme_strerror(rc));

301

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

302

gpgme_strsource(rc), gpgme_strerror(rc));

410

303

plaintext_length = -1;

411

304

if(debug){

412

305

gpgme_decrypt_result_t result;

413

result = gpgme_op_decrypt_result(mc->ctx);

306

result = gpgme_op_decrypt_result(mc.ctx);

414

307

if(result == NULL){

415

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

308

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

416

309

} else {

417

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

418

result->unsupported_algorithm);

419

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

420

result->wrong_key_usage);

310

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

311

result->unsupported_algorithm);

312

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

313

result->wrong_key_usage);

421

314

if(result->file_name != NULL){

422

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

315

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

423

316

}

424

317

gpgme_recipient_t recipient;

425

318

recipient = result->recipients;

426

319

while(recipient != NULL){

427

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

428

gpgme_pubkey_algo_name

429

(recipient->pubkey_algo));

430

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

431

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

432

recipient->status == GPG_ERR_NO_SECKEY

433

? "No" : "Yes");

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");

434

326

recipient = recipient->next;

435

327

}

436

328

}

439

331

}

440

332

441

333

if(debug){

442

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

334

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

443

335

}

444

336

445

337

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

446

338

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

447

perror_plus("gpgme_data_seek");

339

perror("gpgme_data_seek");

448

340

plaintext_length = -1;

449

341

goto decrypt_end;

450

342

}

452

344

*plaintext = NULL;

453

345

while(true){

454

346

plaintext_capacity = incbuffer(plaintext,

455

(size_t)plaintext_length,

456

plaintext_capacity);

347

(size_t)plaintext_length,

348

plaintext_capacity);

457

349

if(plaintext_capacity == 0){

458

perror_plus("incbuffer");

459

plaintext_length = -1;

460

goto decrypt_end;

350

perror("incbuffer");

351

plaintext_length = -1;

352

goto decrypt_end;

461

353

}

462

354

463

355

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

468

360

break;

469

361

}

470

362

if(ret < 0){

471

perror_plus("gpgme_data_read");

363

perror("gpgme_data_read");

472

364

plaintext_length = -1;

473

365

goto decrypt_end;

474

366

}

476

368

}

477

369

478

370

if(debug){

479

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

371

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

480

372

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

481

373

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

482

374

}

493

385

return plaintext_length;

494

386

}

495

387

496

__attribute__((warn_unused_result))

497

static const char *safer_gnutls_strerror(int value){

498

const char *ret = gnutls_strerror(value);

388

static const char * safer_gnutls_strerror(int value){

389

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

390

-Wunreachable-code */

499

391

if(ret == NULL)

500

392

ret = "(unknown)";

501

393

return ret;

502

394

}

503

395

504

396

/* GnuTLS log function callback */

505

__attribute__((nonnull))

506

397

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

507

398

const char* string){

508

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

399

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

509

400

}

510

401

511

__attribute__((nonnull, warn_unused_result))

512

402

static int init_gnutls_global(const char *pubkeyfilename,

513

const char *seckeyfilename,

514

mandos_context *mc){

403

const char *seckeyfilename){

515

404

int ret;

516

405

517

406

if(debug){

518

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

407

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

519

408

}

520

409

521

410

ret = gnutls_global_init();

522

411

if(ret != GNUTLS_E_SUCCESS){

523

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

524

safer_gnutls_strerror(ret));

412

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

413

safer_gnutls_strerror(ret));

525

414

return -1;

526

415

}

527

416

534

423

}

535

424

536

425

/* OpenPGP credentials */

537

ret = gnutls_certificate_allocate_credentials(&mc->cred);

426

gnutls_certificate_allocate_credentials(&mc.cred);

538

427

if(ret != GNUTLS_E_SUCCESS){

539

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

540

safer_gnutls_strerror(ret));

428

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

429

from

430

-Wunreachable-code

431

*/

432

safer_gnutls_strerror(ret));

541

433

gnutls_global_deinit();

542

434

return -1;

543

435

}

544

436

545

437

if(debug){

546

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

547

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

548

pubkeyfilename,

549

seckeyfilename);

438

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

439

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

440

seckeyfilename);

550

441

}

551

442

552

443

ret = gnutls_certificate_set_openpgp_key_file

553

(mc->cred, pubkeyfilename, seckeyfilename,

444

(mc.cred, pubkeyfilename, seckeyfilename,

554

445

GNUTLS_OPENPGP_FMT_BASE64);

555

446

if(ret != GNUTLS_E_SUCCESS){

556

fprintf_plus(stderr,

557

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

558

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

559

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

560

safer_gnutls_strerror(ret));

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));

561

452

goto globalfail;

562

453

}

563

454

564

455

/* GnuTLS server initialization */

565

ret = gnutls_dh_params_init(&mc->dh_params);

456

ret = gnutls_dh_params_init(&mc.dh_params);

566

457

if(ret != GNUTLS_E_SUCCESS){

567

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

568

" initialization: %s\n",

569

safer_gnutls_strerror(ret));

458

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

459

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

570

460

goto globalfail;

571

461

}

572

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

462

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

573

463

if(ret != GNUTLS_E_SUCCESS){

574

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

575

safer_gnutls_strerror(ret));

464

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

465

safer_gnutls_strerror(ret));

576

466

goto globalfail;

577

467

}

578

468

579

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

469

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

580

470

581

471

return 0;

582

472

583

473

globalfail:

584

474

585

gnutls_certificate_free_credentials(mc->cred);

475

gnutls_certificate_free_credentials(mc.cred);

586

476

gnutls_global_deinit();

587

gnutls_dh_params_deinit(mc->dh_params);

477

gnutls_dh_params_deinit(mc.dh_params);

588

478

return -1;

589

479

}

590

480

591

__attribute__((nonnull, warn_unused_result))

592

static int init_gnutls_session(gnutls_session_t *session,

593

mandos_context *mc){

481

static int init_gnutls_session(gnutls_session_t *session){

594

482

int ret;

595

483

/* GnuTLS session creation */

596

484

do {

600

488

}

601

489

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

602

490

if(ret != GNUTLS_E_SUCCESS){

603

fprintf_plus(stderr,

604

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

605

safer_gnutls_strerror(ret));

491

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

492

safer_gnutls_strerror(ret));

606

493

}

607

494

608

495

{

609

496

const char *err;

610

497

do {

611

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

498

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

612

499

if(quit_now){

613

500

gnutls_deinit(*session);

614

501

return -1;

615

502

}

616

503

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

617

504

if(ret != GNUTLS_E_SUCCESS){

618

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

619

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

620

safer_gnutls_strerror(ret));

505

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

506

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

507

safer_gnutls_strerror(ret));

621

508

gnutls_deinit(*session);

622

509

return -1;

623

510

}

625

512

626

513

do {

627

514

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

628

mc->cred);

515

mc.cred);

629

516

if(quit_now){

630

517

gnutls_deinit(*session);

631

518

return -1;

632

519

}

633

520

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

634

521

if(ret != GNUTLS_E_SUCCESS){

635

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

636

safer_gnutls_strerror(ret));

522

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

523

safer_gnutls_strerror(ret));

637

524

gnutls_deinit(*session);

638

525

return -1;

639

526

}

641

528

/* ignore client certificate if any. */

642

529

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

643

530

644

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

531

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

645

532

646

533

return 0;

647

534

}

650

537

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

651

538

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

652

539

653

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

654

__attribute__((warn_unused_result))

655

error_t raise_privileges(void){

656

error_t old_errno = errno;

657

error_t ret_errno = 0;

658

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

659

ret_errno = errno;

660

}

661

errno = old_errno;

662

return ret_errno;

663

}

664

665

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

666

__attribute__((warn_unused_result))

667

error_t raise_privileges_permanently(void){

668

error_t old_errno = errno;

669

error_t ret_errno = raise_privileges();

670

if(ret_errno != 0){

671

errno = old_errno;

672

return ret_errno;

673

}

674

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

675

ret_errno = errno;

676

}

677

errno = old_errno;

678

return ret_errno;

679

}

680

681

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

682

__attribute__((warn_unused_result))

683

error_t lower_privileges(void){

684

error_t old_errno = errno;

685

error_t ret_errno = 0;

686

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

687

ret_errno = errno;

688

}

689

errno = old_errno;

690

return ret_errno;

691

}

692

693

/* Lower privileges permanently */

694

__attribute__((warn_unused_result))

695

error_t lower_privileges_permanently(void){

696

error_t old_errno = errno;

697

error_t ret_errno = 0;

698

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

699

ret_errno = errno;

700

}

701

errno = old_errno;

702

return ret_errno;

703

}

704

705

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

706

__attribute__((nonnull, warn_unused_result))

707

static bool add_remove_local_route(const bool add,

708

const char *address,

709

AvahiIfIndex if_index){

710

int ret;

711

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

712

char add_arg[] = "add";

713

char remove_arg[] = "remove";

714

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

715

if(pluginhelperdir == NULL){

716

if(debug){

717

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

718

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

719

}

720

return false;

721

}

722

723

char interface[IF_NAMESIZE];

724

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

725

perror_plus("if_indextoname");

726

return false;

727

}

728

729

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

730

if(devnull == -1){

731

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

732

return false;

733

}

734

pid_t pid = fork();

735

if(pid == 0){

736

/* Child */

737

/* Raise privileges */

738

errno = raise_privileges_permanently();

739

if(errno != 0){

740

perror_plus("Failed to raise privileges");

741

/* _exit(EX_NOPERM); */

742

} else {

743

/* Set group */

744

errno = 0;

745

ret = setgid(0);

746

if(ret == -1){

747

perror_plus("setgid");

748

_exit(EX_NOPERM);

749

}

750

/* Reset supplementary groups */

751

errno = 0;

752

ret = setgroups(0, NULL);

753

if(ret == -1){

754

perror_plus("setgroups");

755

_exit(EX_NOPERM);

756

}

757

}

758

ret = dup2(devnull, STDIN_FILENO);

759

if(ret == -1){

760

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

761

_exit(EX_OSERR);

762

}

763

ret = close(devnull);

764

if(ret == -1){

765

perror_plus("close");

766

_exit(EX_OSERR);

767

}

768

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

769

if(ret == -1){

770

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

771

_exit(EX_OSERR);

772

}

773

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

774

O_RDONLY

775

| O_DIRECTORY

776

| O_PATH

777

| O_CLOEXEC));

778

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

779

helper, O_RDONLY));

780

TEMP_FAILURE_RETRY(close(helperdir_fd));

781

#ifdef __GNUC__

782

#pragma GCC diagnostic push

783

#pragma GCC diagnostic ignored "-Wcast-qual"

784

#endif

785

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

786

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

787

interface, NULL }, environ) == -1){

788

#ifdef __GNUC__

789

#pragma GCC diagnostic pop

790

#endif

791

perror_plus("fexecve");

792

_exit(EXIT_FAILURE);

793

}

794

}

795

if(pid == -1){

796

perror_plus("fork");

797

return false;

798

}

799

int status;

800

pid_t pret = -1;

801

errno = 0;

802

do {

803

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

804

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

805

int errno_raising = 0;

806

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

807

errno_raising = errno;

808

perror_plus("Failed to raise privileges in order to"

809

" kill helper program");

810

}

811

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

812

perror_plus("kill");

813

}

814

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

815

perror_plus("Failed to lower privileges after killing"

816

" helper program");

817

}

818

return false;

819

}

820

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

821

if(pret == -1){

822

perror_plus("waitpid");

823

return false;

824

}

825

if(WIFEXITED(status)){

826

if(WEXITSTATUS(status) != 0){

827

fprintf_plus(stderr, "Error: iprouteadddel exited"

828

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

829

return false;

830

}

831

return true;

832

}

833

if(WIFSIGNALED(status)){

834

fprintf_plus(stderr, "Error: iprouteadddel died by"

835

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

836

return false;

837

}

838

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

839

return false;

840

}

841

842

__attribute__((nonnull, warn_unused_result))

843

static bool add_local_route(const char *address,

844

AvahiIfIndex if_index){

845

return add_remove_local_route(true, address, if_index);

846

}

847

848

__attribute__((nonnull, warn_unused_result))

849

static bool remove_local_route(const char *address,

850

AvahiIfIndex if_index){

851

return add_remove_local_route(false, address, if_index);

852

}

853

854

540

/* Called when a Mandos server is found */

855

__attribute__((nonnull, warn_unused_result))

856

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

541

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

857

542

AvahiIfIndex if_index,

858

int af, mandos_context *mc){

543

int af){

859

544

int ret, tcp_sd = -1;

860

545

ssize_t sret;

861

struct sockaddr_storage to;

546

union {

547

struct sockaddr_in in;

548

struct sockaddr_in6 in6;

549

} to;

862

550

char *buffer = NULL;

863

551

char *decrypted_buffer = NULL;

864

552

size_t buffer_length = 0;

867

555

int retval = -1;

868

556

gnutls_session_t session;

869

557

int pf; /* Protocol family */

870

bool route_added = false;

871

558

872

559

errno = 0;

873

560

884

571

pf = PF_INET;

885

572

break;

886

573

default:

887

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

574

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

888

575

errno = EINVAL;

889

576

return -1;

890

577

}

891

578

892

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

893

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

894

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

895

bool match = false;

896

{

897

char *interface = NULL;

898

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

899

interface))){

900

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

901

match = true;

902

break;

903

}

904

}

905

}

906

if(not match){

907

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

908

connect to the server */

909

if(debug){

910

char interface[IF_NAMESIZE];

911

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

912

perror_plus("if_indextoname");

913

} else {

914

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

915

" \"%s\"\n",

916

if_indextoname((unsigned int)if_index,

917

interface));

918

}

919

}

920

return -1;

921

}

922

}

923

924

ret = init_gnutls_session(&session, mc);

579

ret = init_gnutls_session(&session);

925

580

if(ret != 0){

926

581

return -1;

927

582

}

928

583

929

584

if(debug){

930

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

931

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

585

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

586

"\n", ip, port);

932

587

}

933

588

934

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

589

tcp_sd = socket(pf, SOCK_STREAM, 0);

935

590

if(tcp_sd < 0){

936

591

int e = errno;

937

perror_plus("socket");

592

perror("socket");

938

593

errno = e;

939

594

goto mandos_end;

940

595

}

946

601

947

602

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

948

603

if(af == AF_INET6){

949

((struct sockaddr_in6 *)&to)->sin6_family = (sa_family_t)af;

950

ret = inet_pton(af, ip, &((struct sockaddr_in6 *)&to)->sin6_addr);

604

to.in6.sin6_family = (sa_family_t)af;

605

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

951

606

} else { /* IPv4 */

952

((struct sockaddr_in *)&to)->sin_family = (sa_family_t)af;

953

ret = inet_pton(af, ip, &((struct sockaddr_in *)&to)->sin_addr);

607

to.in.sin_family = (sa_family_t)af;

608

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

954

609

}

955

610

if(ret < 0 ){

956

611

int e = errno;

957

perror_plus("inet_pton");

612

perror("inet_pton");

958

613

errno = e;

959

614

goto mandos_end;

960

615

}

961

616

if(ret == 0){

962

617

int e = errno;

963

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

618

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

964

619

errno = e;

965

620

goto mandos_end;

966

621

}

967

622

if(af == AF_INET6){

968

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

969

if(IN6_IS_ADDR_LINKLOCAL

970

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

623

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

624

-Wconversion and

625

-Wunreachable-code */

626

627

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

628

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

629

-Wunreachable-code*/

971

630

if(if_index == AVAHI_IF_UNSPEC){

972

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

973

" incomplete without a network interface\n");

631

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

632

" without a network interface\n");

974

633

errno = EINVAL;

975

634

goto mandos_end;

976

635

}

977

636

/* Set the network interface number as scope */

978

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

637

to.in6.sin6_scope_id = (uint32_t)if_index;

979

638

}

980

639

} else {

981

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

640

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

641

-Wconversion and

642

-Wunreachable-code */

982

643

}

983

644

984

645

if(quit_now){

990

651

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

991

652

char interface[IF_NAMESIZE];

992

653

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

993

perror_plus("if_indextoname");

654

perror("if_indextoname");

994

655

} else {

995

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

996

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

656

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

657

ip, interface, port);

997

658

}

998

659

} else {

999

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

1000

ip, (uintmax_t)port);

660

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

661

port);

1001

662

}

1002

663

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

1003

664

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

1004

if(af == AF_INET6){

1005

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

1006

sizeof(struct sockaddr_in6),

1007

addrstr, sizeof(addrstr), NULL, 0,

1008

NI_NUMERICHOST);

1009

} else {

1010

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

1011

sizeof(struct sockaddr_in),

1012

addrstr, sizeof(addrstr), NULL, 0,

1013

NI_NUMERICHOST);

1014

}

1015

if(ret == EAI_SYSTEM){

1016

perror_plus("getnameinfo");

1017

} else if(ret != 0) {

1018

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

1019

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

1020

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

1021

}

1022

}

1023

1024

if(quit_now){

1025

errno = EINTR;

1026

goto mandos_end;

1027

}

1028

1029

while(true){

1030

if(af == AF_INET6){

1031

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

1032

sizeof(struct sockaddr_in6));

1033

} else {

1034

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

1035

sizeof(struct sockaddr_in));

1036

}

1037

if(ret < 0){

1038

if(errno == ENETUNREACH

1039

and if_index != AVAHI_IF_UNSPEC

1040

and connect_to == NULL

1041

and not route_added and

1042

((af == AF_INET6 and not

1043

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1044

&to)->sin6_addr)))

1045

or (af == AF_INET and

1046

/* Not a a IPv4LL address */

1047

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

1048

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

1049

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

1050

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

1051

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

1052

connect to a Mandos server announced by Avahi on a server

1053

host with a global address. Work around this by retrying

1054

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

1055

1056

Avahi bug reference:

1057

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

1058

https://bugs.debian.org/587961

1059

*/

1060

int e = errno;

1061

route_added = add_local_route(ip, if_index);

1062

if(route_added){

1063

continue;

1064

}

1065

errno = e;

1066

}

1067

if(errno != ECONNREFUSED or debug){

1068

int e = errno;

1069

perror_plus("connect");

1070

errno = e;

1071

}

1072

goto mandos_end;

1073

}

1074

1075

if(quit_now){

1076

errno = EINTR;

1077

goto mandos_end;

1078

}

1079

break;

665

const char *pcret;

666

if(af == AF_INET6){

667

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

668

sizeof(addrstr));

669

} else {

670

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

671

sizeof(addrstr));

672

}

673

if(pcret == NULL){

674

perror("inet_ntop");

675

} else {

676

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

677

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

678

}

679

}

680

}

681

682

if(quit_now){

683

errno = EINTR;

684

goto mandos_end;

685

}

686

687

if(af == AF_INET6){

688

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

689

} else {

690

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

691

}

692

if(ret < 0){

693

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

694

int e = errno;

695

perror("connect");

696

errno = e;

697

}

698

goto mandos_end;

699

}

700

701

if(quit_now){

702

errno = EINTR;

703

goto mandos_end;

1080

704

}

1081

705

1082

706

const char *out = mandos_protocol_version;

1084

708

while(true){

1085

709

size_t out_size = strlen(out);

1086

710

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

1087

out_size - written));

711

out_size - written));

1088

712

if(ret == -1){

1089

713

int e = errno;

1090

perror_plus("write");

714

perror("write");

1091

715

errno = e;

1092

716

goto mandos_end;

1093

717

}

1110

734

}

1111

735

1112

736

if(debug){

1113

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

737

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

1114

738

}

1115

739

1116

740

if(quit_now){

1118

742

goto mandos_end;

1119

743

}

1120

744

1121

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

1122

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

1123

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

1124

gnutls_transport_set_ptr(session,

1125

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

745

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1126

746

1127

747

if(quit_now){

1128

748

errno = EINTR;

1139

759

1140

760

if(ret != GNUTLS_E_SUCCESS){

1141

761

if(debug){

1142

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

762

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

1143

763

gnutls_perror(ret);

1144

764

}

1145

765

errno = EPROTO;

1149

769

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

1150

770

1151

771

if(debug){

1152

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

1153

" %s\n", ip);

772

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

773

ip);

1154

774

}

1155

775

1156

776

while(true){

1161

781

}

1162

782

1163

783

buffer_capacity = incbuffer(&buffer, buffer_length,

1164

buffer_capacity);

784

buffer_capacity);

1165

785

if(buffer_capacity == 0){

1166

786

int e = errno;

1167

perror_plus("incbuffer");

787

perror("incbuffer");

1168

788

errno = e;

1169

789

goto mandos_end;

1170

790

}

1194

814

}

1195

815

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

1196

816

if(ret < 0){

1197

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

1198

"***\n");

817

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

1199

818

gnutls_perror(ret);

1200

819

errno = EPROTO;

1201

820

goto mandos_end;

1202

821

}

1203

822

break;

1204

823

default:

1205

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

1206

" encrypted session with Mandos server\n");

824

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

825

" encrypted session with Mandos server\n");

1207

826

gnutls_bye(session, GNUTLS_SHUT_RDWR);

1208

827

errno = EIO;

1209

828

goto mandos_end;

1214

833

}

1215

834

1216

835

if(debug){

1217

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

836

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

1218

837

}

1219

838

1220

839

if(quit_now){

1232

851

1233

852

if(buffer_length > 0){

1234

853

ssize_t decrypted_buffer_size;

1235

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1236

&decrypted_buffer, mc);

854

decrypted_buffer_size = pgp_packet_decrypt(buffer,

855

buffer_length,

856

&decrypted_buffer);

1237

857

if(decrypted_buffer_size >= 0){

1238

858

1239

859

written = 0;

1249

869

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

1250

870

int e = errno;

1251

871

if(debug){

1252

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

1253

strerror(errno));

872

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

873

strerror(errno));

1254

874

}

1255

875

errno = e;

1256

876

goto mandos_end;

1265

885

1266

886

mandos_end:

1267

887

{

1268

if(route_added){

1269

if(not remove_local_route(ip, if_index)){

1270

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

1271

" interface %d", ip, if_index);

1272

}

1273

}

1274

888

int e = errno;

1275

889

free(decrypted_buffer);

1276

890

free(buffer);

1281

895

if(e == 0){

1282

896

e = errno;

1283

897

}

1284

perror_plus("close");

898

perror("close");

1285

899

}

1286

900

gnutls_deinit(session);

1287

errno = e;

1288

901

if(quit_now){

1289

errno = EINTR;

902

e = EINTR;

1290

903

retval = -1;

1291

904

}

905

errno = e;

1292

906

}

1293

907

return retval;

1294

908

}

1295

909

1296

__attribute__((nonnull))

1297

910

static void resolve_callback(AvahiSServiceResolver *r,

1298

911

AvahiIfIndex interface,

1299

912

AvahiProtocol proto,

1307

920

AVAHI_GCC_UNUSED AvahiStringList *txt,

1308

921

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1309

922

flags,

1310

void *mc){

1311

if(r == NULL){

1312

return;

1313

}

923

AVAHI_GCC_UNUSED void* userdata){

924

assert(r);

1314

925

1315

926

/* Called whenever a service has been resolved successfully or

1316

927

timed out */

1317

928

1318

929

if(quit_now){

1319

avahi_s_service_resolver_free(r);

1320

930

return;

1321

931

}

1322

932

1323

933

switch(event){

1324

934

default:

1325

935

case AVAHI_RESOLVER_FAILURE:

1326

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

1327

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

1328

domain,

1329

avahi_strerror(avahi_server_errno

1330

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

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)));

1331

939

break;

1332

940

1333

941

case AVAHI_RESOLVER_FOUND:

1335

943

char ip[AVAHI_ADDRESS_STR_MAX];

1336

944

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

1337

945

if(debug){

1338

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

1339

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

1340

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

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);

1341

949

}

1342

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

1343

interface,

1344

avahi_proto_to_af(proto),

1345

mc);

950

int ret = start_mandos_communication(ip, port, interface,

951

avahi_proto_to_af(proto));

1346

952

if(ret == 0){

1347

avahi_simple_poll_quit(simple_poll);

1348

} else {

1349

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

1350

avahi_proto_to_af(proto),

1351

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

1352

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

1353

" list\n", name);

1354

}

953

avahi_simple_poll_quit(mc.simple_poll);

1355

954

}

1356

955

}

1357

956

}

1367

966

const char *domain,

1368

967

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1369

968

flags,

1370

void *mc){

1371

if(b == NULL){

1372

return;

1373

}

969

AVAHI_GCC_UNUSED void* userdata){

970

assert(b);

1374

971

1375

972

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

1376

973

is removed from the LAN */

1383

980

default:

1384

981

case AVAHI_BROWSER_FAILURE:

1385

982

1386

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

1387

avahi_strerror(avahi_server_errno

1388

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

1389

avahi_simple_poll_quit(simple_poll);

983

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

984

avahi_strerror(avahi_server_errno(mc.server)));

985

avahi_simple_poll_quit(mc.simple_poll);

1390

986

return;

1391

987

1392

988

case AVAHI_BROWSER_NEW:

1395

991

the callback function is called the Avahi server will free the

1396

992

resolver for us. */

1397

993

1398

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

1399

interface, protocol, name, type,

1400

domain, protocol, 0,

1401

resolve_callback, mc) == NULL)

1402

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

1403

" %s\n", name,

1404

avahi_strerror(avahi_server_errno

1405

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

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)));

1406

999

break;

1407

1000

1408

1001

case AVAHI_BROWSER_REMOVE:

1411

1004

case AVAHI_BROWSER_ALL_FOR_NOW:

1412

1005

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1413

1006

if(debug){

1414

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

1415

" searching...\n");

1007

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

1416

1008

}

1417

1009

break;

1418

1010

}

1419

1011

}

1420

1012

1421

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

1013

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

1422

1014

static void handle_sigterm(int sig){

1423

1015

if(quit_now){

1424

1016

return;

1426

1018

quit_now = 1;

1427

1019

signal_received = sig;

1428

1020

int old_errno = errno;

1429

/* set main loop to exit */

1430

if(simple_poll != NULL){

1431

avahi_simple_poll_quit(simple_poll);

1021

if(mc.simple_poll != NULL){

1022

avahi_simple_poll_quit(mc.simple_poll);

1432

1023

}

1433

1024

errno = old_errno;

1434

1025

}

1435

1026

1436

__attribute__((nonnull, warn_unused_result))

1437

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

1438

int ret;

1439

error_t ret_errno;

1440

1441

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

1442

if(s < 0){

1443

ret_errno = errno;

1444

perror_plus("socket");

1445

errno = ret_errno;

1446

return false;

1447

}

1448

strcpy(ifr->ifr_name, ifname);

1449

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1450

if(ret == -1){

1451

if(debug){

1452

ret_errno = errno;

1453

perror_plus("ioctl SIOCGIFFLAGS");

1454

errno = ret_errno;

1455

}

1456

return false;

1457

}

1458

return true;

1459

}

1460

1461

__attribute__((nonnull, warn_unused_result))

1462

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

1463

1464

/* Reject the loopback device */

1465

if(ifr->ifr_flags & IFF_LOOPBACK){

1466

if(debug){

1467

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

1468

ifname);

1469

}

1470

return false;

1471

}

1472

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

1473

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

1474

if(debug){

1475

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

1476

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

1477

}

1478

return true;

1479

}

1480

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

1481

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

1482

if(debug){

1483

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1484

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

1485

}

1486

return false;

1487

}

1488

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

1489

if(ifr->ifr_flags & IFF_NOARP){

1490

if(debug){

1491

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

1492

ifname);

1493

}

1494

return false;

1495

}

1496

1497

/* Accept this device */

1498

if(debug){

1499

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

1500

}

1501

return true;

1502

}

1503

1504

1027

/*

1505

1028

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

1506

1029

* corresponds to an acceptable network device.

1507

1030

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

1508

1031

*/

1509

__attribute__((nonnull, warn_unused_result))

1510

1032

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

}

1511

1041

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

1512

1042

return 0;

1513

1043

}

1514

1515

struct ifreq ifr;

1516

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

1517

if(debug){

1518

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

1519

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

1520

}

1521

return 0;

1522

}

1523

1524

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

1525

return 0;

1526

}

1527

return 1;

1528

}

1529

1530

/*

1531

* This function determines if a network interface is up.

1532

*/

1533

__attribute__((nonnull, warn_unused_result))

1534

bool interface_is_up(const char *interface){

1535

struct ifreq ifr;

1536

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

1537

if(debug){

1538

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

1539

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

1540

}

1541

return false;

1542

}

1543

1544

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

1545

}

1546

1547

/*

1548

* This function determines if a network interface is running

1549

*/

1550

__attribute__((nonnull, warn_unused_result))

1551

bool interface_is_running(const char *interface){

1552

struct ifreq ifr;

1553

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

1554

if(debug){

1555

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

1556

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

1557

}

1558

return false;

1559

}

1560

1561

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

1562

}

1563

1564

__attribute__((nonnull, pure, warn_unused_result))

1565

int notdotentries(const struct dirent *direntry){

1566

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

1567

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

1568

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

1569

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

1570

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

1571

return 0;

1572

}

1573

return 1;

1574

}

1575

1576

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

1577

__attribute__((nonnull, warn_unused_result))

1578

int runnable_hook(const struct dirent *direntry){

1579

int ret;

1580

size_t sret;

1581

struct stat st;

1582

1583

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

1584

/* Empty name? */

1585

return 0;

1586

}

1587

1588

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

1589

"abcdefghijklmnopqrstuvwxyz"

1590

"0123456789"

1591

"_.-");

1592

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

1593

/* Contains non-allowed characters */

1594

if(debug){

1595

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

1596

direntry->d_name);

1597

}

1598

return 0;

1599

}

1600

1601

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

1602

if(ret == -1){

1603

if(debug){

1604

perror_plus("Could not stat hook");

1605

}

1606

return 0;

1607

}

1608

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

1609

/* Not a regular file */

1610

if(debug){

1611

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

1612

direntry->d_name);

1613

}

1614

return 0;

1615

}

1616

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

1617

/* Not executable */

1618

if(debug){

1619

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

1620

direntry->d_name);

1621

}

1622

return 0;

1623

}

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){

1070

break;

1071

}

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 */

1624

1115

if(debug){

1625

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

1626

direntry->d_name);

1116

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

1117

if_entry->d_name);

1627

1118

}

1628

1119

return 1;

1629

1120

}

1630

1121

1631

__attribute__((nonnull, warn_unused_result))

1632

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1633

mandos_context *mc){

1634

int ret;

1635

struct timespec now;

1636

struct timespec waited_time;

1637

intmax_t block_time;

1638

1639

while(true){

1640

if(mc->current_server == NULL){

1641

if(debug){

1642

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

1643

" No timeout!\n");

1644

}

1645

ret = avahi_simple_poll_iterate(s, -1);

1646

} else {

1647

if(debug){

1648

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

1649

" it, or wait\n");

1650

}

1651

/* the current time */

1652

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1653

if(ret == -1){

1654

perror_plus("clock_gettime");

1655

return -1;

1656

}

1657

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

1658

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

1659

waited_time.tv_sec = (now.tv_sec

1660

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

1661

waited_time.tv_nsec = (now.tv_nsec

1662

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

1663

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

1664

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

1665

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

1666

block_time = ((retry_interval

1667

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

1668

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

1669

1670

if(debug){

1671

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

1672

block_time);

1673

}

1674

1675

if(block_time <= 0){

1676

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

1677

mc->current_server->port,

1678

mc->current_server->if_index,

1679

mc->current_server->af, mc);

1680

if(ret == 0){

1681

avahi_simple_poll_quit(s);

1682

return 0;

1683

}

1684

ret = clock_gettime(CLOCK_MONOTONIC,

1685

&mc->current_server->last_seen);

1686

if(ret == -1){

1687

perror_plus("clock_gettime");

1688

return -1;

1689

}

1690

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

1691

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

1692

servers, but don't block */

1693

}

1694

1695

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

1696

}

1697

if(ret != 0){

1698

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

1699

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

1700

}

1701

}

1702

}

1703

}

1704

1705

__attribute__((nonnull))

1706

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

1707

const float delay){

1708

struct dirent **direntries = NULL;

1709

if(hookdir_fd == -1){

1710

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1711

| O_CLOEXEC);

1712

if(hookdir_fd == -1){

1713

if(errno == ENOENT){

1714

if(debug){

1715

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

1716

" found\n", hookdir);

1717

}

1718

} else {

1719

perror_plus("open");

1720

}

1721

return;

1722

}

1723

}

1724

#ifdef __GLIBC__

1725

#if __GLIBC_PREREQ(2, 15)

1726

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

1727

runnable_hook, alphasort);

1728

#else /* not __GLIBC_PREREQ(2, 15) */

1729

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

1730

alphasort);

1731

#endif /* not __GLIBC_PREREQ(2, 15) */

1732

#else /* not __GLIBC__ */

1733

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

1734

alphasort);

1735

#endif /* not __GLIBC__ */

1736

if(numhooks == -1){

1737

perror_plus("scandir");

1738

return;

1739

}

1740

struct dirent *direntry;

1741

int ret;

1742

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

1743

if(devnull == -1){

1744

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

1745

return;

1746

}

1747

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

1748

direntry = direntries[i];

1749

if(debug){

1750

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

1751

direntry->d_name);

1752

}

1753

pid_t hook_pid = fork();

1754

if(hook_pid == 0){

1755

/* Child */

1756

/* Raise privileges */

1757

errno = raise_privileges_permanently();

1758

if(errno != 0){

1759

perror_plus("Failed to raise privileges");

1760

_exit(EX_NOPERM);

1761

}

1762

/* Set group */

1763

errno = 0;

1764

ret = setgid(0);

1765

if(ret == -1){

1766

perror_plus("setgid");

1767

_exit(EX_NOPERM);

1768

}

1769

/* Reset supplementary groups */

1770

errno = 0;

1771

ret = setgroups(0, NULL);

1772

if(ret == -1){

1773

perror_plus("setgroups");

1774

_exit(EX_NOPERM);

1775

}

1776

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

1777

if(ret == -1){

1778

perror_plus("setenv");

1779

_exit(EX_OSERR);

1780

}

1781

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

1782

if(ret == -1){

1783

perror_plus("setenv");

1784

_exit(EX_OSERR);

1785

}

1786

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

1787

if(ret == -1){

1788

perror_plus("setenv");

1789

_exit(EX_OSERR);

1790

}

1791

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

1792

if(ret == -1){

1793

perror_plus("setenv");

1794

_exit(EX_OSERR);

1795

}

1796

char *delaystring;

1797

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

1798

if(ret == -1){

1799

perror_plus("asprintf");

1800

_exit(EX_OSERR);

1801

}

1802

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

1803

if(ret == -1){

1804

free(delaystring);

1805

perror_plus("setenv");

1806

_exit(EX_OSERR);

1807

}

1808

free(delaystring);

1809

if(connect_to != NULL){

1810

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

1811

if(ret == -1){

1812

perror_plus("setenv");

1813

_exit(EX_OSERR);

1814

}

1815

}

1816

int hook_fd = TEMP_FAILURE_RETRY(openat(hookdir_fd,

1817

direntry->d_name,

1818

O_RDONLY));

1819

if(hook_fd == -1){

1820

perror_plus("openat");

1821

_exit(EXIT_FAILURE);

1822

}

1823

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

1824

perror_plus("close");

1825

_exit(EXIT_FAILURE);

1826

}

1827

ret = dup2(devnull, STDIN_FILENO);

1828

if(ret == -1){

1829

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

1830

_exit(EX_OSERR);

1831

}

1832

ret = close(devnull);

1833

if(ret == -1){

1834

perror_plus("close");

1835

_exit(EX_OSERR);

1836

}

1837

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1838

if(ret == -1){

1839

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

1840

_exit(EX_OSERR);

1841

}

1842

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

1843

environ) == -1){

1844

perror_plus("fexecve");

1845

_exit(EXIT_FAILURE);

1846

}

1847

} else {

1848

if(hook_pid == -1){

1849

perror_plus("fork");

1850

free(direntry);

1851

continue;

1852

}

1853

int status;

1854

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

1855

perror_plus("waitpid");

1856

free(direntry);

1857

continue;

1858

}

1859

if(WIFEXITED(status)){

1860

if(WEXITSTATUS(status) != 0){

1861

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

1862

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

1863

WEXITSTATUS(status));

1864

free(direntry);

1865

continue;

1866

}

1867

} else if(WIFSIGNALED(status)){

1868

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

1869

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

1870

WTERMSIG(status));

1871

free(direntry);

1872

continue;

1873

} else {

1874

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

1875

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

1876

free(direntry);

1877

continue;

1878

}

1879

}

1880

if(debug){

1881

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

1882

direntry->d_name);

1883

}

1884

free(direntry);

1885

}

1886

free(direntries);

1887

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

1888

perror_plus("close");

1889

} else {

1890

hookdir_fd = -1;

1891

}

1892

close(devnull);

1893

}

1894

1895

__attribute__((nonnull, warn_unused_result))

1896

error_t bring_up_interface(const char *const interface,

1897

const float delay){

1898

error_t old_errno = errno;

1899

int ret;

1900

struct ifreq network;

1901

unsigned int if_index = if_nametoindex(interface);

1902

if(if_index == 0){

1903

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

1904

errno = old_errno;

1905

return ENXIO;

1906

}

1907

1908

if(quit_now){

1909

errno = old_errno;

1910

return EINTR;

1911

}

1912

1913

if(not interface_is_up(interface)){

1914

error_t ret_errno = 0, ioctl_errno = 0;

1915

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

1916

ret_errno = errno;

1917

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

1918

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

1919

errno = old_errno;

1920

return ret_errno;

1921

}

1922

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

1923

1924

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

1925

if(sd == -1){

1926

ret_errno = errno;

1927

perror_plus("socket");

1928

errno = old_errno;

1929

return ret_errno;

1930

}

1931

1932

if(quit_now){

1933

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

1934

if(ret == -1){

1935

perror_plus("close");

1936

}

1937

errno = old_errno;

1938

return EINTR;

1939

}

1940

1941

if(debug){

1942

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

1943

interface);

1944

}

1945

1946

/* Raise privileges */

1947

ret_errno = raise_privileges();

1948

if(ret_errno != 0){

1949

errno = ret_errno;

1950

perror_plus("Failed to raise privileges");

1951

}

1952

1953

#ifdef __linux__

1954

int ret_linux;

1955

bool restore_loglevel = false;

1956

if(ret_errno == 0){

1957

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1958

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

1959

ret_linux = klogctl(8, NULL, 5);

1960

if(ret_linux == -1){

1961

perror_plus("klogctl");

1962

} else {

1963

restore_loglevel = true;

1964

}

1965

}

1966

#endif /* __linux__ */

1967

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

1968

ioctl_errno = errno;

1969

#ifdef __linux__

1970

if(restore_loglevel){

1971

ret_linux = klogctl(7, NULL, 0);

1972

if(ret_linux == -1){

1973

perror_plus("klogctl");

1974

}

1975

}

1976

#endif /* __linux__ */

1977

1978

/* If raise_privileges() succeeded above */

1979

if(ret_errno == 0){

1980

/* Lower privileges */

1981

ret_errno = lower_privileges();

1982

if(ret_errno != 0){

1983

errno = ret_errno;

1984

perror_plus("Failed to lower privileges");

1985

}

1986

}

1987

1988

/* Close the socket */

1989

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

1990

if(ret == -1){

1991

perror_plus("close");

1992

}

1993

1994

if(ret_setflags == -1){

1995

errno = ioctl_errno;

1996

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1997

errno = old_errno;

1998

return ioctl_errno;

1999

}

2000

} else if(debug){

2001

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

2002

interface);

2003

}

2004

2005

/* Sleep checking until interface is running.

2006

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

2007

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

2008

if(interface_is_running(interface)){

2009

break;

2010

}

2011

struct timespec sleeptime = { .tv_nsec = 250000000 };

2012

ret = nanosleep(&sleeptime, NULL);

2013

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

2014

perror_plus("nanosleep");

2015

}

2016

}

2017

2018

errno = old_errno;

2019

return 0;

2020

}

2021

2022

__attribute__((nonnull, warn_unused_result))

2023

error_t take_down_interface(const char *const interface){

2024

error_t old_errno = errno;

2025

struct ifreq network;

2026

unsigned int if_index = if_nametoindex(interface);

2027

if(if_index == 0){

2028

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

2029

errno = old_errno;

2030

return ENXIO;

2031

}

2032

if(interface_is_up(interface)){

2033

error_t ret_errno = 0, ioctl_errno = 0;

2034

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

2035

ret_errno = errno;

2036

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

2037

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

2038

errno = old_errno;

2039

return ret_errno;

2040

}

2041

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

2042

2043

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

2044

if(sd == -1){

2045

ret_errno = errno;

2046

perror_plus("socket");

2047

errno = old_errno;

2048

return ret_errno;

2049

}

2050

2051

if(debug){

2052

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

2053

interface);

2054

}

2055

2056

/* Raise privileges */

2057

ret_errno = raise_privileges();

2058

if(ret_errno != 0){

2059

errno = ret_errno;

2060

perror_plus("Failed to raise privileges");

2061

}

2062

2063

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

2064

ioctl_errno = errno;

2065

2066

/* If raise_privileges() succeeded above */

2067

if(ret_errno == 0){

2068

/* Lower privileges */

2069

ret_errno = lower_privileges();

2070

if(ret_errno != 0){

2071

errno = ret_errno;

2072

perror_plus("Failed to lower privileges");

2073

}

2074

}

2075

2076

/* Close the socket */

2077

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

2078

if(ret == -1){

2079

perror_plus("close");

2080

}

2081

2082

if(ret_setflags == -1){

2083

errno = ioctl_errno;

2084

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2085

errno = old_errno;

2086

return ioctl_errno;

2087

}

2088

} else if(debug){

2089

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

2090

interface);

2091

}

2092

2093

errno = old_errno;

2094

return 0;

2095

}

2096

2097

1122

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

2098

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

2099

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

2100

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

2101

.interfaces = NULL, .interfaces_size = 0 };

2102

1123

AvahiSServiceBrowser *sb = NULL;

2103

error_t ret_errno;

1124

int error;

2104

1125

int ret;

2105

1126

intmax_t tmpmax;

2106

1127

char *tmp;

2107

1128

int exitcode = EXIT_SUCCESS;

2108

char *interfaces_to_take_down = NULL;

2109

size_t interfaces_to_take_down_size = 0;

2110

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

2111

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

2112

char *tempdir = NULL;

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;

1135

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

1136

bool tempdir_created = false;

2113

1137

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2114

1138

const char *seckey = PATHDIR "/" SECKEY;

2115

1139

const char *pubkey = PATHDIR "/" PUBKEY;

2116

char *interfaces_hooks = NULL;

2117

1140

2118

1141

bool gnutls_initialized = false;

2119

1142

bool gpgme_initialized = false;

2120

1143

float delay = 2.5f;

2121

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

2122

retrying the same server again */

2123

1144

2124

1145

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

2125

1146

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

2131

1152

errno = 0;

2132

1153

ret = setgid(gid);

2133

1154

if(ret == -1){

2134

perror_plus("setgid");

1155

perror("setgid");

2135

1156

}

2136

1157

2137

1158

/* Lower user privileges (temporarily) */

2138

1159

errno = 0;

2139

1160

ret = seteuid(uid);

2140

1161

if(ret == -1){

2141

perror_plus("seteuid");

1162

perror("seteuid");

2142

1163

}

2143

1164

2144

1165

if(quit_now){

2179

1200

.arg = "SECONDS",

2180

1201

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

2181

1202

.group = 2 },

2182

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

2183

.arg = "SECONDS",

2184

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

2185

.group = 2 },

2186

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

2187

.arg = "DIR",

2188

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

2189

.group = 2 },

2190

1203

/*

2191

1204

* These reproduce what we would get without ARGP_NO_HELP

2192

1205

*/

2210

1223

connect_to = arg;

2211

1224

break;

2212

1225

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

2213

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

2214

arg, (int)',');

2215

if(ret_errno != 0){

2216

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

2217

}

1226

interface = arg;

2218

1227

break;

2219

1228

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

2220

1229

seckey = arg;

2240

1249

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

2241

1250

argp_error(state, "Bad delay");

2242

1251

}

2243

case 132: /* --retry */

2244

errno = 0;

2245

retry_interval = strtod(arg, &tmp);

2246

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

2247

or (retry_interval * 1000) > INT_MAX

2248

or retry_interval < 0){

2249

argp_error(state, "Bad retry interval");

2250

}

2251

break;

2252

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

2253

hookdir = arg;

2254

1252

break;

2255

1253

/*

2256

1254

* These reproduce what we would get without ARGP_NO_HELP

2263

1261

argp_state_help(state, state->out_stream,

2264

1262

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2265

1263

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

2266

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

1264

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

2267

1265

exit(argp_err_exit_status);

2268

1266

break;

2269

1267

default:

2284

1282

case ENOMEM:

2285

1283

default:

2286

1284

errno = ret;

2287

perror_plus("argp_parse");

1285

perror("argp_parse");

2288

1286

exitcode = EX_OSERR;

2289

1287

goto end;

2290

1288

case EINVAL:

2293

1291

}

2294

1292

}

2295

1293

2296

{

2297

/* Work around Debian bug #633582:

2298

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

2299

2300

/* Re-raise privileges */

2301

ret_errno = raise_privileges();

2302

if(ret_errno != 0){

2303

errno = ret_errno;

2304

perror_plus("Failed to raise privileges");

2305

} else {

2306

struct stat st;

2307

2308

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

2309

int seckey_fd = open(seckey, O_RDONLY);

2310

if(seckey_fd == -1){

2311

perror_plus("open");

2312

} else {

2313

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

2314

if(ret == -1){

2315

perror_plus("fstat");

2316

} else {

2317

if(S_ISREG(st.st_mode)

2318

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

2319

ret = fchown(seckey_fd, uid, gid);

2320

if(ret == -1){

2321

perror_plus("fchown");

2322

}

2323

}

2324

}

2325

TEMP_FAILURE_RETRY(close(seckey_fd));

2326

}

2327

}

2328

2329

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

2330

int pubkey_fd = open(pubkey, O_RDONLY);

2331

if(pubkey_fd == -1){

2332

perror_plus("open");

2333

} else {

2334

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

2335

if(ret == -1){

2336

perror_plus("fstat");

2337

} else {

2338

if(S_ISREG(st.st_mode)

2339

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

2340

ret = fchown(pubkey_fd, uid, gid);

2341

if(ret == -1){

2342

perror_plus("fchown");

2343

}

2344

}

2345

}

2346

TEMP_FAILURE_RETRY(close(pubkey_fd));

2347

}

2348

}

2349

2350

/* Lower privileges */

2351

ret_errno = lower_privileges();

2352

if(ret_errno != 0){

2353

errno = ret_errno;

2354

perror_plus("Failed to lower privileges");

2355

}

2356

}

2357

}

2358

2359

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

2360

{

2361

char *interface = NULL;

2362

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

2363

interface))){

2364

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

2365

and if_nametoindex(interface) == 0){

2366

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

2367

fprintf_plus(stderr, "Not using nonexisting interface"

2368

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

2369

}

2370

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

2371

interface = NULL;

2372

}

2373

}

2374

}

2375

2376

/* Run network hooks */

2377

{

2378

if(mc.interfaces != NULL){

2379

interfaces_hooks = malloc(mc.interfaces_size);

2380

if(interfaces_hooks == NULL){

2381

perror_plus("malloc");

2382

goto end;

2383

}

2384

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

2385

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

2386

}

2387

run_network_hooks("start", interfaces_hooks != NULL ?

2388

interfaces_hooks : "", delay);

2389

}

2390

2391

1294

if(not debug){

2392

1295

avahi_set_log_function(empty_log);

2393

1296

}

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

}

2394

1322

2395

1323

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

2396

1324

from the signal handler */

2397

1325

/* Initialize the pseudo-RNG for Avahi */

2398

1326

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

2399

simple_poll = avahi_simple_poll_new();

2400

if(simple_poll == NULL){

2401

fprintf_plus(stderr,

2402

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

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");

2403

1330

exitcode = EX_UNAVAILABLE;

2404

1331

goto end;

2405

1332

}

2407

1334

sigemptyset(&sigterm_action.sa_mask);

2408

1335

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

2409

1336

if(ret == -1){

2410

perror_plus("sigaddset");

1337

perror("sigaddset");

2411

1338

exitcode = EX_OSERR;

2412

1339

goto end;

2413

1340

}

2414

1341

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

2415

1342

if(ret == -1){

2416

perror_plus("sigaddset");

1343

perror("sigaddset");

2417

1344

exitcode = EX_OSERR;

2418

1345

goto end;

2419

1346

}

2420

1347

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

2421

1348

if(ret == -1){

2422

perror_plus("sigaddset");

1349

perror("sigaddset");

2423

1350

exitcode = EX_OSERR;

2424

1351

goto end;

2425

1352

}

2429

1356

*/

2430

1357

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

2431

1358

if(ret == -1){

2432

perror_plus("sigaction");

1359

perror("sigaction");

2433

1360

return EX_OSERR;

2434

1361

}

2435

1362

if(old_sigterm_action.sa_handler != SIG_IGN){

2436

1363

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

2437

1364

if(ret == -1){

2438

perror_plus("sigaction");

1365

perror("sigaction");

2439

1366

exitcode = EX_OSERR;

2440

1367

goto end;

2441

1368

}

2442

1369

}

2443

1370

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

2444

1371

if(ret == -1){

2445

perror_plus("sigaction");

1372

perror("sigaction");

2446

1373

return EX_OSERR;

2447

1374

}

2448

1375

if(old_sigterm_action.sa_handler != SIG_IGN){

2449

1376

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

2450

1377

if(ret == -1){

2451

perror_plus("sigaction");

1378

perror("sigaction");

2452

1379

exitcode = EX_OSERR;

2453

1380

goto end;

2454

1381

}

2455

1382

}

2456

1383

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

2457

1384

if(ret == -1){

2458

perror_plus("sigaction");

1385

perror("sigaction");

2459

1386

return EX_OSERR;

2460

1387

}

2461

1388

if(old_sigterm_action.sa_handler != SIG_IGN){

2462

1389

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

2463

1390

if(ret == -1){

2464

perror_plus("sigaction");

1391

perror("sigaction");

2465

1392

exitcode = EX_OSERR;

2466

1393

goto end;

2467

1394

}

2468

1395

}

2469

1396

2470

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

2471

if(mc.interfaces == NULL){

2472

struct dirent **direntries = NULL;

2473

/* Look for any good interfaces */

2474

ret = scandir(sys_class_net, &direntries, good_interface,

2475

alphasort);

2476

if(ret >= 1){

2477

/* Add all found interfaces to interfaces list */

2478

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

2479

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

2480

direntries[i]->d_name);

2481

if(ret_errno != 0){

2482

errno = ret_errno;

2483

perror_plus("argz_add");

2484

free(direntries[i]);

2485

continue;

2486

}

2487

if(debug){

2488

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

2489

direntries[i]->d_name);

2490

}

2491

free(direntries[i]);

2492

}

2493

free(direntries);

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");

1482

}

1483

}

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

break;

1501

}

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

}

2494

1532

} else {

2495

if(ret == 0){

2496

free(direntries);

2497

}

2498

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

2499

exitcode = EXIT_FAILURE;

2500

goto end;

2501

}

2502

}

2503

2504

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

2505

{

2506

char *interface = NULL;

2507

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

2508

interface))){

2509

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

2510

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

2511

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

2512

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

2513

interface);

2514

interface = NULL;

2515

while((interface = argz_next(mc.interfaces,

2516

mc.interfaces_size, interface))){

2517

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

2518

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

2519

interface);

2520

interface = NULL;

2521

}

2522

}

2523

break;

2524

}

2525

bool interface_was_up = interface_is_up(interface);

2526

errno = bring_up_interface(interface, delay);

2527

if(not interface_was_up){

2528

if(errno != 0){

2529

perror_plus("Failed to bring up interface");

2530

} else {

2531

errno = argz_add(&interfaces_to_take_down,

2532

&interfaces_to_take_down_size,

2533

interface);

2534

if(errno != 0){

2535

perror_plus("argz_add");

2536

}

2537

}

2538

}

2539

}

2540

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

2541

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

2542

}

2543

}

2544

2545

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

2546

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

2547

if(debug){

2548

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

2549

mc.interfaces);

2550

}

2551

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

1533

/* Lower privileges permanently */

1534

ret = setuid(uid);

1535

if(ret == -1){

1536

perror("setuid");

1537

}

1538

}

2552

1539

}

2553

1540

2554

1541

if(quit_now){

2555

1542

goto end;

2556

1543

}

2557

1544

2558

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

1545

ret = init_gnutls_global(pubkey, seckey);

2559

1546

if(ret == -1){

2560

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

1547

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

2561

1548

exitcode = EX_UNAVAILABLE;

2562

1549

goto end;

2563

1550

} else {

2568

1555

goto end;

2569

1556

}

2570

1557

2571

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

2572

tempdir = mkdtemp(run_tempdir);

2573

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

2574

if(debug){

2575

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

2576

run_tempdir, old_tempdir);

2577

}

2578

tempdir = mkdtemp(old_tempdir);

2579

}

2580

if(tempdir == NULL){

2581

perror_plus("mkdtemp");

1558

tempdir_created = true;

1559

if(mkdtemp(tempdir) == NULL){

1560

tempdir_created = false;

1561

perror("mkdtemp");

2582

1562

goto end;

2583

1563

}

2584

1564

2586

1566

goto end;

2587

1567

}

2588

1568

2589

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

2590

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

1569

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

1570

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

2591

1571

exitcode = EX_UNAVAILABLE;

2592

1572

goto end;

2593

1573

} else {

2602

1582

/* Connect directly, do not use Zeroconf */

2603

1583

/* (Mainly meant for debugging) */

2604

1584

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

2605

2606

1585

if(address == NULL){

2607

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

1586

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

2608

1587

exitcode = EX_USAGE;

2609

1588

goto end;

2610

1589

}

2613

1592

goto end;

2614

1593

}

2615

1594

2616

in_port_t port;

1595

uint16_t port;

2617

1596

errno = 0;

2618

1597

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

2619

1598

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

2620

or tmpmax != (in_port_t)tmpmax){

2621

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

1599

or tmpmax != (uint16_t)tmpmax){

1600

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

2622

1601

exitcode = EX_USAGE;

2623

1602

goto end;

2624

1603

}

2625

1604

2626

1605

if(quit_now){

2627

1606

goto end;

2628

1607

}

2629

1608

2630

port = (in_port_t)tmpmax;

1609

port = (uint16_t)tmpmax;

2631

1610

*address = '\0';

1611

address = connect_to;

2632

1612

/* Colon in address indicates IPv6 */

2633

1613

int af;

2634

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

1614

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

2635

1615

af = AF_INET6;

2636

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

2637

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

2638

{

2639

connect_to++;

2640

address[-1] = '\0';

2641

}

2642

1616

} else {

2643

1617

af = AF_INET;

2644

1618

}

2645

address = connect_to;

2646

1619

2647

1620

if(quit_now){

2648

1621

goto end;

2649

1622

}

2650

1623

2651

1624

while(not quit_now){

2652

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

2653

&mc);

1625

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

2654

1626

if(quit_now or ret == 0){

2655

1627

break;

2656

1628

}

2657

if(debug){

2658

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

2659

(int)retry_interval);

2660

}

2661

sleep((unsigned int)retry_interval);

2662

}

2663

2664

if(not quit_now){

1629

sleep(15);

1630

};

1631

1632

if (not quit_now){

2665

1633

exitcode = EXIT_SUCCESS;

2666

1634

}

2667

1635

2668

1636

goto end;

2669

1637

}

2670

1638

2682

1650

config.publish_domain = 0;

2683

1651

2684

1652

/* Allocate a new server */

2685

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2686

&config, NULL, NULL, &ret_errno);

1653

mc.server = avahi_server_new(avahi_simple_poll_get

1654

(mc.simple_poll), &config, NULL,

1655

NULL, &error);

2687

1656

2688

1657

/* Free the Avahi configuration data */

2689

1658

avahi_server_config_free(&config);

2691

1660

2692

1661

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

2693

1662

if(mc.server == NULL){

2694

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

2695

avahi_strerror(ret_errno));

1663

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

1664

avahi_strerror(error));

2696

1665

exitcode = EX_UNAVAILABLE;

2697

1666

goto end;

2698

1667

}

2704

1673

/* Create the Avahi service browser */

2705

1674

sb = avahi_s_service_browser_new(mc.server, if_index,

2706

1675

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2707

NULL, 0, browse_callback,

2708

(void *)&mc);

1676

NULL, 0, browse_callback, NULL);

2709

1677

if(sb == NULL){

2710

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

2711

avahi_strerror(avahi_server_errno(mc.server)));

1678

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

1679

avahi_strerror(avahi_server_errno(mc.server)));

2712

1680

exitcode = EX_UNAVAILABLE;

2713

1681

goto end;

2714

1682

}

2720

1688

/* Run the main loop */

2721

1689

2722

1690

if(debug){

2723

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

1691

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

2724

1692

}

2725

1693

2726

ret = avahi_loop_with_timeout(simple_poll,

2727

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

2728

if(debug){

2729

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

2730

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

2731

}

1694

avahi_simple_poll_loop(mc.simple_poll);

2732

1695

2733

1696

end:

2734

1697

2735

1698

if(debug){

2736

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

1699

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

2737

1700

}

2738

1701

2739

1702

/* Cleanup things */

2740

free(mc.interfaces);

2741

2742

1703

if(sb != NULL)

2743

1704

avahi_s_service_browser_free(sb);

2744

1705

2745

1706

if(mc.server != NULL)

2746

1707

avahi_server_free(mc.server);

2747

1708

2748

if(simple_poll != NULL)

2749

avahi_simple_poll_free(simple_poll);

1709

if(mc.simple_poll != NULL)

1710

avahi_simple_poll_free(mc.simple_poll);

2750

1711

2751

1712

if(gnutls_initialized){

2752

1713

gnutls_certificate_free_credentials(mc.cred);

2758

1719

gpgme_release(mc.ctx);

2759

1720

}

2760

1721

2761

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

2762

has seen */

2763

if(mc.current_server != NULL){

2764

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

2765

while(mc.current_server != NULL){

2766

server *next = mc.current_server->next;

2767

#ifdef __GNUC__

2768

#pragma GCC diagnostic push

2769

#pragma GCC diagnostic ignored "-Wcast-qual"

2770

#endif

2771

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

2772

#ifdef __GNUC__

2773

#pragma GCC diagnostic pop

2774

#endif

2775

free(mc.current_server);

2776

mc.current_server = next;

2777

}

2778

}

2779

2780

/* Re-raise privileges */

2781

{

2782

ret_errno = raise_privileges();

2783

if(ret_errno != 0){

2784

errno = ret_errno;

2785

perror_plus("Failed to raise privileges");

2786

} else {

2787

2788

/* Run network hooks */

2789

run_network_hooks("stop", interfaces_hooks != NULL ?

2790

interfaces_hooks : "", delay);

2791

2792

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

2793

{

2794

char *interface = NULL;

2795

while((interface=argz_next(interfaces_to_take_down,

2796

interfaces_to_take_down_size,

2797

interface))){

2798

ret_errno = take_down_interface(interface);

2799

if(ret_errno != 0){

2800

errno = ret_errno;

2801

perror_plus("Failed to take down interface");

2802

}

2803

}

2804

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

2805

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

2806

" down\n");

2807

}

2808

}

2809

}

2810

2811

ret_errno = lower_privileges_permanently();

2812

if(ret_errno != 0){

2813

errno = ret_errno;

2814

perror_plus("Failed to lower privileges permanently");

2815

}

2816

}

2817

2818

free(interfaces_to_take_down);

2819

free(interfaces_hooks);

2820

2821

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

2822

if(tempdir != NULL){

2823

struct dirent **direntries = NULL;

2824

int tempdir_fd = (int)TEMP_FAILURE_RETRY(open(tempdir, O_RDONLY

2825

| O_NOFOLLOW

2826

| O_DIRECTORY

2827

| O_PATH));

2828

if(tempdir_fd == -1){

2829

perror_plus("open");

2830

} else {

2831

#ifdef __GLIBC__

2832

#if __GLIBC_PREREQ(2, 15)

2833

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

2834

notdotentries, alphasort);

2835

#else /* not __GLIBC_PREREQ(2, 15) */

2836

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

2837

alphasort);

2838

#endif /* not __GLIBC_PREREQ(2, 15) */

2839

#else /* not __GLIBC__ */

2840

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

2841

alphasort);

2842

#endif /* not __GLIBC__ */

2843

if(numentries >= 0){

2844

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

2845

ret = unlinkat(tempdir_fd, direntries[i]->d_name, 0);

2846

if(ret == -1){

2847

fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"

2848

" \"%s\", 0): %s\n", tempdir,

2849

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

2850

}

2851

free(direntries[i]);

2852

}

2853

2854

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

2855

free(direntries);

2856

if(numentries == -1){

2857

perror_plus("scandir");

2858

}

2859

ret = rmdir(tempdir);

2860

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

2861

perror_plus("rmdir");

2862

}

2863

}

2864

TEMP_FAILURE_RETRY(close(tempdir_fd));

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");

1729

}

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");

1739

}

1740

}

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");

1750

}

1751

}

1752

}

1753

1754

/* Removes the temp directory used by GPGME */

1755

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

}

1776

char *fullname = NULL;

1777

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

1778

direntry->d_name);

1779

if(ret < 0){

1780

perror("asprintf");

1781

continue;

1782

}

1783

ret = remove(fullname);

1784

if(ret == -1){

1785

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

1786

strerror(errno));

1787

}

1788

free(fullname);

1789

}

1790

closedir(d);

1791

}

1792

ret = rmdir(tempdir);

1793

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

1794

perror("rmdir");

2865

1795

}

2866

1796

}

2867

1797

2872

1802

&old_sigterm_action,

2873

1803

NULL));

2874

1804

if(ret == -1){

2875

perror_plus("sigaction");

1805

perror("sigaction");

2876

1806

}

2877

1807

do {

2878

1808

ret = raise(signal_received);

2879

1809

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

2880

1810

if(ret != 0){

2881

perror_plus("raise");

1811

perror("raise");

2882

1812

abort();

2883

1813

}

2884

1814

TEMP_FAILURE_RETRY(pause());