/mandos/trunk : revision 237.4.20

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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

32

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

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

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program_invocation_short_name */

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

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*/

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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, inet_ntop() */

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

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

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argp_state, struct argp,

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raise() */

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

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EX_NOHOST, EX_IOERR, EX_PROTOCOL */

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

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WEXITSTATUS(), WTERMSIG() */

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

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

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argz_delete(), argz_append(),

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argz_stringify(), argz_add(),

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argz_count() */

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#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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GNUTLS_* */

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#include <gnutls/openpgp.h>

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/* gnutls_certificate_set_openpgp_key_file(),

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GNUTLS_OPENPGP_FMT_BASE64 */

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/* gnutls_certificate_set_openpgp_key_file(),

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GNUTLS_OPENPGP_FMT_BASE64 */

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/* GPGME */

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

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

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#define SECKEY "seckey.txt"

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#define PUBKEY "pubkey.txt"

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

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bool debug = false;

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static const char mandos_protocol_version[] = "1";

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

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

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char *connect_to = NULL;

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const char *hookdir = HOOKDIR;

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int hookdir_fd = -1;

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uid_t uid = 65534;

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gid_t gid = 65534;

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

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typedef struct server{

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const char *ip;

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in_port_t port;

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uint16_t port;

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AvahiIfIndex if_index;

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int af;

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struct timespec last_seen;

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

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typedef struct {

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AvahiSimplePoll *simple_poll;

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AvahiServer *server;

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gnutls_certificate_credentials_t cred;

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150

unsigned int dh_bits;

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const char *priority;

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gpgme_ctx_t ctx;

168

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server *current_server;

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char *interfaces;

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size_t interfaces_size;

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} mandos_context;

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/* global so signal handler can reach it*/

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AvahiSimplePoll *simple_poll;

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

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

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.dh_bits = 1024, .priority = "SECURE256"

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

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.current_server = NULL };

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sig_atomic_t quit_now = 0;

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int signal_received = 0;

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/* Function to use when printing errors */

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void perror_plus(const char *print_text){

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int e = errno;

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

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169

program_invocation_short_name);

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errno = e;

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170

perror(print_text);

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}

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

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

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va_list ap;

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va_start (ap, format);

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

194

program_invocation_short_name));

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

196

}

197

198

173

/*

199

174

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

200

175

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

201

176

* "buffer_length" is how much is already used.

202

177

*/

203

__attribute__((nonnull, warn_unused_result))

204

178

size_t incbuffer(char **buffer, size_t buffer_length,

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size_t buffer_capacity){

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size_t buffer_capacity){

206

180

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;

210

free(*buffer);

211

errno = old_errno;

212

*buffer = NULL;

181

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

182

if(buffer == NULL){

213

183

return 0;

214

184

}

215

*buffer = new_buf;

216

185

buffer_capacity += BUFFER_SIZE;

217

186

}

218

187

return buffer_capacity;

219

188

}

220

189

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

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__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 add_server(const char *ip, uint16_t port,

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AvahiIfIndex if_index,

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int af){

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194

int ret;

226

195

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

227

196

if(new_server == NULL){

228

197

perror_plus("malloc");

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return false;

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return -1;

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199

}

231

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

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.port = port,

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.if_index = if_index,

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.af = af };

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.port = port,

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.if_index = if_index,

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.af = af };

235

204

if(new_server->ip == NULL){

236

205

perror_plus("strdup");

237

free(new_server);

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return false;

239

}

240

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

241

if(ret == -1){

242

perror_plus("clock_gettime");

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#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;

206

return -1;

253

207

}

254

208

/* Special case of first server */

255

if(*current_server == NULL){

209

if (mc.current_server == NULL){

256

210

new_server->next = new_server;

257

211

new_server->prev = new_server;

258

*current_server = new_server;

212

mc.current_server = new_server;

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

259

214

} else {

260

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

261

new_server->next = *current_server;

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

215

new_server->next = mc.current_server;

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

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new_server->prev->next = new_server;

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(*current_server)->prev = new_server;

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}

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return true;

218

mc.current_server->prev = new_server;

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}

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

221

if(ret == -1){

222

perror_plus("clock_gettime");

223

return -1;

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}

225

return 0;

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}

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227

269

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/*

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* Initialize GPGME.

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*/

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__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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233

gpgme_error_t rc;

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gpgme_engine_info_t engine_info;

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236

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/*

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

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239

*/

283

bool import_key(const char * const filename){

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bool import_key(const char *filename){

284

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int ret;

285

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int fd;

286

243

gpgme_data_t pgp_data;

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250

294

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rc = gpgme_data_new_from_fd(&pgp_data, fd);

295

252

if(rc != GPG_ERR_NO_ERROR){

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

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}

300

257

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

258

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));

260

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

261

gpgme_strsource(rc), gpgme_strerror(rc));

305

262

return false;

306

263

}

307

264

314

271

}

315

272

316

273

if(debug){

317

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

274

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

318

275

}

319

276

320

277

/* Init GPGME */

321

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gpgme_check_version(NULL);

322

279

rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

323

280

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));

281

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

282

gpgme_strsource(rc), gpgme_strerror(rc));

326

283

return false;

327

284

}

328

285

329

286

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

330

287

rc = gpgme_get_engine_info(&engine_info);

331

288

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));

289

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

290

gpgme_strsource(rc), gpgme_strerror(rc));

334

291

return false;

335

292

}

336

293

while(engine_info != NULL){

342

299

engine_info = engine_info->next;

343

300

}

344

301

if(engine_info == NULL){

345

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

346

tempdir);

302

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

347

303

return false;

348

304

}

349

305

350

306

/* Create new GPGME "context" */

351

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

307

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

352

308

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));

309

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

310

gpgme_strsource(rc), gpgme_strerror(rc));

356

311

return false;

357

312

}

358

313

367

322

* Decrypt OpenPGP data.

368

323

* Returns -1 on error

369

324

*/

370

__attribute__((nonnull, warn_unused_result))

371

325

static ssize_t pgp_packet_decrypt(const char *cryptotext,

372

326

size_t crypto_size,

373

char **plaintext,

374

mandos_context *mc){

327

char **plaintext){

375

328

gpgme_data_t dh_crypto, dh_plain;

376

329

gpgme_error_t rc;

377

330

ssize_t ret;

379

332

ssize_t plaintext_length = 0;

380

333

381

334

if(debug){

382

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

335

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

383

336

}

384

337

385

338

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

386

339

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

387

340

0);

388

341

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));

342

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

343

gpgme_strsource(rc), gpgme_strerror(rc));

391

344

return -1;

392

345

}

393

346

394

347

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

395

348

rc = gpgme_data_new(&dh_plain);

396

349

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));

350

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

351

gpgme_strsource(rc), gpgme_strerror(rc));

400

352

gpgme_data_release(dh_crypto);

401

353

return -1;

402

354

}

403

355

404

356

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

405

357

data buffer */

406

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

358

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

407

359

if(rc != GPG_ERR_NO_ERROR){

408

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

409

gpgme_strsource(rc), gpgme_strerror(rc));

360

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

361

gpgme_strsource(rc), gpgme_strerror(rc));

410

362

plaintext_length = -1;

411

363

if(debug){

412

364

gpgme_decrypt_result_t result;

413

result = gpgme_op_decrypt_result(mc->ctx);

365

result = gpgme_op_decrypt_result(mc.ctx);

414

366

if(result == NULL){

415

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

367

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

416

368

} 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);

369

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

370

result->unsupported_algorithm);

371

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

372

result->wrong_key_usage);

421

373

if(result->file_name != NULL){

422

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

374

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

423

375

}

424

376

gpgme_recipient_t recipient;

425

377

recipient = result->recipients;

426

378

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");

379

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

380

gpgme_pubkey_algo_name(recipient->pubkey_algo));

381

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

382

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

383

recipient->status == GPG_ERR_NO_SECKEY

384

? "No" : "Yes");

434

385

recipient = recipient->next;

435

386

}

436

387

}

439

390

}

440

391

441

392

if(debug){

442

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

393

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

443

394

}

444

395

445

396

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

452

403

*plaintext = NULL;

453

404

while(true){

454

405

plaintext_capacity = incbuffer(plaintext,

455

(size_t)plaintext_length,

456

plaintext_capacity);

406

(size_t)plaintext_length,

407

plaintext_capacity);

457

408

if(plaintext_capacity == 0){

458

perror_plus("incbuffer");

459

plaintext_length = -1;

460

goto decrypt_end;

409

perror_plus("incbuffer");

410

plaintext_length = -1;

411

goto decrypt_end;

461

412

}

462

413

463

414

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

476

427

}

477

428

478

429

if(debug){

479

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

430

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

480

431

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

481

432

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

482

433

}

493

444

return plaintext_length;

494

445

}

495

446

496

__attribute__((warn_unused_result, const))

497

static const char *safe_string(const char *str){

498

if(str == NULL)

499

return "(unknown)";

500

return str;

501

}

502

503

__attribute__((warn_unused_result))

504

static const char *safer_gnutls_strerror(int value){

505

const char *ret = gnutls_strerror(value);

506

return safe_string(ret);

447

static const char * safer_gnutls_strerror(int value){

448

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

449

-Wunreachable-code */

450

if(ret == NULL)

451

ret = "(unknown)";

452

return ret;

507

453

}

508

454

509

455

/* GnuTLS log function callback */

510

__attribute__((nonnull))

511

456

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

512

457

const char* string){

513

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

458

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

514

459

}

515

460

516

__attribute__((nonnull, warn_unused_result))

517

461

static int init_gnutls_global(const char *pubkeyfilename,

518

const char *seckeyfilename,

519

mandos_context *mc){

462

const char *seckeyfilename){

520

463

int ret;

521

unsigned int uret;

522

464

523

465

if(debug){

524

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

466

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

525

467

}

526

468

527

469

ret = gnutls_global_init();

528

470

if(ret != GNUTLS_E_SUCCESS){

529

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

530

safer_gnutls_strerror(ret));

471

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

472

safer_gnutls_strerror(ret));

531

473

return -1;

532

474

}

533

475

540

482

}

541

483

542

484

/* OpenPGP credentials */

543

ret = gnutls_certificate_allocate_credentials(&mc->cred);

485

ret = gnutls_certificate_allocate_credentials(&mc.cred);

544

486

if(ret != GNUTLS_E_SUCCESS){

545

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

546

safer_gnutls_strerror(ret));

487

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

488

safer_gnutls_strerror(ret));

547

489

gnutls_global_deinit();

548

490

return -1;

549

491

}

550

492

551

493

if(debug){

552

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

553

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

554

pubkeyfilename,

555

seckeyfilename);

494

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

495

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

496

seckeyfilename);

556

497

}

557

498

558

499

ret = gnutls_certificate_set_openpgp_key_file

559

(mc->cred, pubkeyfilename, seckeyfilename,

500

(mc.cred, pubkeyfilename, seckeyfilename,

560

501

GNUTLS_OPENPGP_FMT_BASE64);

561

502

if(ret != GNUTLS_E_SUCCESS){

562

fprintf_plus(stderr,

563

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

564

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

565

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

566

safer_gnutls_strerror(ret));

503

fprintf(stderr,

504

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

505

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

506

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

507

safer_gnutls_strerror(ret));

567

508

goto globalfail;

568

509

}

569

510

570

511

/* GnuTLS server initialization */

571

ret = gnutls_dh_params_init(&mc->dh_params);

512

ret = gnutls_dh_params_init(&mc.dh_params);

572

513

if(ret != GNUTLS_E_SUCCESS){

573

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

574

" initialization: %s\n",

575

safer_gnutls_strerror(ret));

514

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

515

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

576

516

goto globalfail;

577

517

}

578

if(mc->dh_bits == 0){

579

/* Find out the optimal number of DH bits */

580

/* Try to read the private key file */

581

gnutls_datum_t buffer = { .data = NULL, .size = 0 };

582

{

583

int secfile = open(seckeyfilename, O_RDONLY);

584

size_t buffer_capacity = 0;

585

while(true){

586

buffer_capacity = incbuffer((char **)&buffer.data,

587

(size_t)buffer.size,

588

(size_t)buffer_capacity);

589

if(buffer_capacity == 0){

590

perror_plus("incbuffer");

591

free(buffer.data);

592

buffer.data = NULL;

593

break;

594

}

595

ssize_t bytes_read = read(secfile, buffer.data + buffer.size,

596

BUFFER_SIZE);

597

/* EOF */

598

if(bytes_read == 0){

599

break;

600

}

601

/* check bytes_read for failure */

602

if(bytes_read < 0){

603

perror_plus("read");

604

free(buffer.data);

605

buffer.data = NULL;

606

break;

607

}

608

buffer.size += (unsigned int)bytes_read;

609

}

610

close(secfile);

611

}

612

/* If successful, use buffer to parse private key */

613

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

614

if(buffer.data != NULL){

615

{

616

gnutls_openpgp_privkey_t privkey = NULL;

617

ret = gnutls_openpgp_privkey_init(&privkey);

618

if(ret != GNUTLS_E_SUCCESS){

619

fprintf_plus(stderr, "Error initializing OpenPGP key"

620

" structure: %s", safer_gnutls_strerror(ret));

621

free(buffer.data);

622

buffer.data = NULL;

623

} else {

624

ret = gnutls_openpgp_privkey_import(privkey, &buffer,

625

GNUTLS_OPENPGP_FMT_BASE64,

626

"", 0);

627

if(ret != GNUTLS_E_SUCCESS){

628

fprintf_plus(stderr, "Error importing OpenPGP key : %s",

629

safer_gnutls_strerror(ret));

630

privkey = NULL;

631

}

632

free(buffer.data);

633

buffer.data = NULL;

634

if(privkey != NULL){

635

/* Use private key to suggest an appropriate sec_param */

636

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

637

gnutls_openpgp_privkey_deinit(privkey);

638

if(debug){

639

fprintf_plus(stderr, "This OpenPGP key implies using a"

640

" GnuTLS security parameter \"%s\".\n",

641

safe_string(gnutls_sec_param_get_name

642

(sec_param)));

643

}

644

}

645

}

646

}

647

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

648

/* Err on the side of caution */

649

sec_param = GNUTLS_SEC_PARAM_ULTRA;

650

if(debug){

651

fprintf_plus(stderr, "Falling back to security parameter"

652

" \"%s\"\n",

653

safe_string(gnutls_sec_param_get_name

654

(sec_param)));

655

}

656

}

657

}

658

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

659

if(uret != 0){

660

mc->dh_bits = uret;

661

if(debug){

662

fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"

663

" implies %u DH bits; using that.\n",

664

safe_string(gnutls_sec_param_get_name

665

(sec_param)),

666

mc->dh_bits);

667

}

668

} else {

669

fprintf_plus(stderr, "Failed to get implied number of DH"

670

" bits for security parameter \"%s\"): %s\n",

671

safe_string(gnutls_sec_param_get_name(sec_param)),

672

safer_gnutls_strerror(ret));

673

goto globalfail;

674

}

675

} else if(debug){

676

fprintf_plus(stderr, "DH bits explicitly set to %u\n",

677

mc->dh_bits);

678

}

679

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

518

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

680

519

if(ret != GNUTLS_E_SUCCESS){

681

fprintf_plus(stderr, "Error in GnuTLS prime generation (%u bits):"

682

" %s\n", mc->dh_bits, safer_gnutls_strerror(ret));

520

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

521

safer_gnutls_strerror(ret));

683

522

goto globalfail;

684

523

}

685

524

686

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

525

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

687

526

688

527

return 0;

689

528

690

529

globalfail:

691

530

692

gnutls_certificate_free_credentials(mc->cred);

531

gnutls_certificate_free_credentials(mc.cred);

693

532

gnutls_global_deinit();

694

gnutls_dh_params_deinit(mc->dh_params);

533

gnutls_dh_params_deinit(mc.dh_params);

695

534

return -1;

696

535

}

697

536

698

__attribute__((nonnull, warn_unused_result))

699

static int init_gnutls_session(gnutls_session_t *session,

700

mandos_context *mc){

537

static int init_gnutls_session(gnutls_session_t *session){

701

538

int ret;

702

539

/* GnuTLS session creation */

703

540

do {

707

544

}

708

545

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

709

546

if(ret != GNUTLS_E_SUCCESS){

710

fprintf_plus(stderr,

711

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

712

safer_gnutls_strerror(ret));

547

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

548

safer_gnutls_strerror(ret));

713

549

}

714

550

715

551

{

716

552

const char *err;

717

553

do {

718

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

554

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

719

555

if(quit_now){

720

556

gnutls_deinit(*session);

721

557

return -1;

722

558

}

723

559

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

724

560

if(ret != GNUTLS_E_SUCCESS){

725

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

726

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

727

safer_gnutls_strerror(ret));

561

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

562

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

563

safer_gnutls_strerror(ret));

728

564

gnutls_deinit(*session);

729

565

return -1;

730

566

}

732

568

733

569

do {

734

570

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

735

mc->cred);

571

mc.cred);

736

572

if(quit_now){

737

573

gnutls_deinit(*session);

738

574

return -1;

739

575

}

740

576

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

741

577

if(ret != GNUTLS_E_SUCCESS){

742

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

743

safer_gnutls_strerror(ret));

578

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

579

safer_gnutls_strerror(ret));

744

580

gnutls_deinit(*session);

745

581

return -1;

746

582

}

748

584

/* ignore client certificate if any. */

749

585

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

750

586

751

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

587

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

752

588

753

589

return 0;

754

590

}

757

593

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

758

594

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

759

595

760

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

761

__attribute__((warn_unused_result))

762

error_t raise_privileges(void){

763

error_t old_errno = errno;

764

error_t ret_errno = 0;

765

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

766

ret_errno = errno;

767

}

768

errno = old_errno;

769

return ret_errno;

770

}

771

772

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

773

__attribute__((warn_unused_result))

774

error_t raise_privileges_permanently(void){

775

error_t old_errno = errno;

776

error_t ret_errno = raise_privileges();

777

if(ret_errno != 0){

778

errno = old_errno;

779

return ret_errno;

780

}

781

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

782

ret_errno = errno;

783

}

784

errno = old_errno;

785

return ret_errno;

786

}

787

788

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

789

__attribute__((warn_unused_result))

790

error_t lower_privileges(void){

791

error_t old_errno = errno;

792

error_t ret_errno = 0;

793

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

794

ret_errno = errno;

795

}

796

errno = old_errno;

797

return ret_errno;

798

}

799

800

/* Lower privileges permanently */

801

__attribute__((warn_unused_result))

802

error_t lower_privileges_permanently(void){

803

error_t old_errno = errno;

804

error_t ret_errno = 0;

805

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

806

ret_errno = errno;

807

}

808

errno = old_errno;

809

return ret_errno;

810

}

811

812

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

813

__attribute__((nonnull, warn_unused_result))

814

static bool add_delete_local_route(const bool add,

815

const char *address,

816

AvahiIfIndex if_index){

817

int ret;

818

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

819

char add_arg[] = "add";

820

char delete_arg[] = "delete";

821

char debug_flag[] = "--debug";

822

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

823

if(pluginhelperdir == NULL){

824

if(debug){

825

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

826

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

827

}

828

return false;

829

}

830

831

char interface[IF_NAMESIZE];

832

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

833

perror_plus("if_indextoname");

834

return false;

835

}

836

837

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

838

if(devnull == -1){

839

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

840

return false;

841

}

842

pid_t pid = fork();

843

if(pid == 0){

844

/* Child */

845

/* Raise privileges */

846

errno = raise_privileges_permanently();

847

if(errno != 0){

848

perror_plus("Failed to raise privileges");

849

/* _exit(EX_NOPERM); */

850

} else {

851

/* Set group */

852

errno = 0;

853

ret = setgid(0);

854

if(ret == -1){

855

perror_plus("setgid");

856

_exit(EX_NOPERM);

857

}

858

/* Reset supplementary groups */

859

errno = 0;

860

ret = setgroups(0, NULL);

861

if(ret == -1){

862

perror_plus("setgroups");

863

_exit(EX_NOPERM);

864

}

865

}

866

ret = dup2(devnull, STDIN_FILENO);

867

if(ret == -1){

868

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

869

_exit(EX_OSERR);

870

}

871

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

872

if(ret == -1){

873

perror_plus("close");

874

_exit(EX_OSERR);

875

}

876

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

877

if(ret == -1){

878

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

879

_exit(EX_OSERR);

880

}

881

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

882

O_RDONLY

883

| O_DIRECTORY

884

| O_PATH

885

| O_CLOEXEC));

886

if(helperdir_fd == -1){

887

perror_plus("open");

888

_exit(EX_UNAVAILABLE);

889

}

890

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

891

helper, O_RDONLY));

892

if(helper_fd == -1){

893

perror_plus("openat");

894

_exit(EX_UNAVAILABLE);

895

}

896

TEMP_FAILURE_RETRY(close(helperdir_fd));

897

#ifdef __GNUC__

898

#pragma GCC diagnostic push

899

#pragma GCC diagnostic ignored "-Wcast-qual"

900

#endif

901

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

902

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

903

interface, debug ? debug_flag : NULL, NULL },

904

environ) == -1){

905

#ifdef __GNUC__

906

#pragma GCC diagnostic pop

907

#endif

908

perror_plus("fexecve");

909

_exit(EXIT_FAILURE);

910

}

911

}

912

if(pid == -1){

913

perror_plus("fork");

914

return false;

915

}

916

int status;

917

pid_t pret = -1;

918

errno = 0;

919

do {

920

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

921

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

922

int errno_raising = 0;

923

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

924

errno_raising = errno;

925

perror_plus("Failed to raise privileges in order to"

926

" kill helper program");

927

}

928

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

929

perror_plus("kill");

930

}

931

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

932

perror_plus("Failed to lower privileges after killing"

933

" helper program");

934

}

935

return false;

936

}

937

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

938

if(pret == -1){

939

perror_plus("waitpid");

940

return false;

941

}

942

if(WIFEXITED(status)){

943

if(WEXITSTATUS(status) != 0){

944

fprintf_plus(stderr, "Error: iprouteadddel exited"

945

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

946

return false;

947

}

948

return true;

949

}

950

if(WIFSIGNALED(status)){

951

fprintf_plus(stderr, "Error: iprouteadddel died by"

952

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

953

return false;

954

}

955

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

956

return false;

957

}

958

959

__attribute__((nonnull, warn_unused_result))

960

static bool add_local_route(const char *address,

961

AvahiIfIndex if_index){

962

if(debug){

963

fprintf_plus(stderr, "Adding route to %s\n", address);

964

}

965

return add_delete_local_route(true, address, if_index);

966

}

967

968

__attribute__((nonnull, warn_unused_result))

969

static bool delete_local_route(const char *address,

970

AvahiIfIndex if_index){

971

if(debug){

972

fprintf_plus(stderr, "Removing route to %s\n", address);

973

}

974

return add_delete_local_route(false, address, if_index);

975

}

976

977

596

/* Called when a Mandos server is found */

978

__attribute__((nonnull, warn_unused_result))

979

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

597

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

980

598

AvahiIfIndex if_index,

981

int af, mandos_context *mc){

599

int af){

982

600

int ret, tcp_sd = -1;

983

601

ssize_t sret;

984

struct sockaddr_storage to;

602

union {

603

struct sockaddr_in in;

604

struct sockaddr_in6 in6;

605

} to;

985

606

char *buffer = NULL;

986

607

char *decrypted_buffer = NULL;

987

608

size_t buffer_length = 0;

990

611

int retval = -1;

991

612

gnutls_session_t session;

992

613

int pf; /* Protocol family */

993

bool route_added = false;

994

614

995

615

errno = 0;

996

616

1007

627

pf = PF_INET;

1008

628

break;

1009

629

default:

1010

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

630

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

1011

631

errno = EINVAL;

1012

632

return -1;

1013

633

}

1014

634

1015

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

1016

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

1017

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

1018

bool match = false;

1019

{

1020

char *interface = NULL;

1021

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

1022

interface))){

1023

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

1024

match = true;

1025

break;

1026

}

1027

}

1028

}

1029

if(not match){

1030

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

1031

connect to the server */

1032

if(debug){

1033

char interface[IF_NAMESIZE];

1034

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

1035

perror_plus("if_indextoname");

1036

} else {

1037

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

1038

" \"%s\"\n",

1039

if_indextoname((unsigned int)if_index,

1040

interface));

1041

}

1042

}

1043

return -1;

1044

}

1045

}

1046

1047

ret = init_gnutls_session(&session, mc);

635

ret = init_gnutls_session(&session);

1048

636

if(ret != 0){

1049

637

return -1;

1050

638

}

1051

639

1052

640

if(debug){

1053

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

1054

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

641

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

642

"\n", ip, port);

1055

643

}

1056

644

1057

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

645

tcp_sd = socket(pf, SOCK_STREAM, 0);

1058

646

if(tcp_sd < 0){

1059

647

int e = errno;

1060

648

perror_plus("socket");

1069

657

1070

658

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

1071

659

if(af == AF_INET6){

1072

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

1073

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

660

to.in6.sin6_family = (sa_family_t)af;

661

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

1074

662

} else { /* IPv4 */

1075

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

1076

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

663

to.in.sin_family = (sa_family_t)af;

664

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

1077

665

}

1078

666

if(ret < 0 ){

1079

667

int e = errno;

1083

671

}

1084

672

if(ret == 0){

1085

673

int e = errno;

1086

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

674

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

1087

675

errno = e;

1088

676

goto mandos_end;

1089

677

}

1090

678

if(af == AF_INET6){

1091

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

1092

if(IN6_IS_ADDR_LINKLOCAL

1093

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

679

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

680

-Wconversion and

681

-Wunreachable-code */

682

683

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

684

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

685

-Wunreachable-code*/

1094

686

if(if_index == AVAHI_IF_UNSPEC){

1095

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

1096

" incomplete without a network interface\n");

687

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

688

" without a network interface\n");

1097

689

errno = EINVAL;

1098

690

goto mandos_end;

1099

691

}

1100

692

/* Set the network interface number as scope */

1101

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

693

to.in6.sin6_scope_id = (uint32_t)if_index;

1102

694

}

1103

695

} else {

1104

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

696

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

697

-Wconversion and

698

-Wunreachable-code */

1105

699

}

1106

700

1107

701

if(quit_now){

1115

709

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

1116

710

perror_plus("if_indextoname");

1117

711

} else {

1118

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

1119

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

712

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

713

ip, interface, port);

1120

714

}

1121

715

} else {

1122

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

1123

ip, (uintmax_t)port);

716

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

717

port);

1124

718

}

1125

719

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

1126

720

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

1127

if(af == AF_INET6){

1128

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

1129

sizeof(struct sockaddr_in6),

1130

addrstr, sizeof(addrstr), NULL, 0,

1131

NI_NUMERICHOST);

1132

} else {

1133

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

1134

sizeof(struct sockaddr_in),

1135

addrstr, sizeof(addrstr), NULL, 0,

1136

NI_NUMERICHOST);

1137

}

1138

if(ret == EAI_SYSTEM){

1139

perror_plus("getnameinfo");

1140

} else if(ret != 0) {

1141

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

1142

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

1143

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

1144

}

1145

}

1146

1147

if(quit_now){

1148

errno = EINTR;

1149

goto mandos_end;

1150

}

1151

1152

while(true){

1153

if(af == AF_INET6){

1154

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

1155

sizeof(struct sockaddr_in6));

1156

} else {

1157

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

1158

sizeof(struct sockaddr_in));

1159

}

1160

if(ret < 0){

1161

if(errno == ENETUNREACH

1162

and if_index != AVAHI_IF_UNSPEC

1163

and connect_to == NULL

1164

and not route_added and

1165

((af == AF_INET6 and not

1166

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1167

&to)->sin6_addr)))

1168

or (af == AF_INET and

1169

/* Not a a IPv4LL address */

1170

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

1171

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

1172

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

1173

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

1174

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

1175

connect to a Mandos server announced by Avahi on a server

1176

host with a global address. Work around this by retrying

1177

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

1178

1179

Avahi bug reference:

1180

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

1181

https://bugs.debian.org/587961

1182

*/

1183

if(debug){

1184

fprintf_plus(stderr, "Mandos server unreachable, trying"

1185

" direct route\n");

1186

}

1187

int e = errno;

1188

route_added = add_local_route(ip, if_index);

1189

if(route_added){

1190

continue;

1191

}

1192

errno = e;

1193

}

1194

if(errno != ECONNREFUSED or debug){

1195

int e = errno;

1196

perror_plus("connect");

1197

errno = e;

1198

}

1199

goto mandos_end;

1200

}

1201

1202

if(quit_now){

1203

errno = EINTR;

1204

goto mandos_end;

1205

}

1206

break;

721

const char *pcret;

722

if(af == AF_INET6){

723

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

724

sizeof(addrstr));

725

} else {

726

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

727

sizeof(addrstr));

728

}

729

if(pcret == NULL){

730

perror_plus("inet_ntop");

731

} else {

732

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

733

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

734

}

735

}

736

}

737

738

if(quit_now){

739

errno = EINTR;

740

goto mandos_end;

741

}

742

743

if(af == AF_INET6){

744

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

745

} else {

746

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

747

}

748

if(ret < 0){

749

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

750

int e = errno;

751

perror_plus("connect");

752

errno = e;

753

}

754

goto mandos_end;

755

}

756

757

if(quit_now){

758

errno = EINTR;

759

goto mandos_end;

1207

760

}

1208

761

1209

762

const char *out = mandos_protocol_version;

1211

764

while(true){

1212

765

size_t out_size = strlen(out);

1213

766

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

1214

out_size - written));

767

out_size - written));

1215

768

if(ret == -1){

1216

769

int e = errno;

1217

770

perror_plus("write");

1237

790

}

1238

791

1239

792

if(debug){

1240

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

793

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

1241

794

}

1242

795

1243

796

if(quit_now){

1245

798

goto mandos_end;

1246

799

}

1247

800

1248

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

1249

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

1250

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

1251

gnutls_transport_set_ptr(session,

1252

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

801

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

802

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1253

803

1254

804

if(quit_now){

1255

805

errno = EINTR;

1266

816

1267

817

if(ret != GNUTLS_E_SUCCESS){

1268

818

if(debug){

1269

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

819

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

1270

820

gnutls_perror(ret);

1271

821

}

1272

822

errno = EPROTO;

1276

826

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

1277

827

1278

828

if(debug){

1279

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

1280

" %s\n", ip);

829

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

830

ip);

1281

831

}

1282

832

1283

833

while(true){

1288

838

}

1289

839

1290

840

buffer_capacity = incbuffer(&buffer, buffer_length,

1291

buffer_capacity);

841

buffer_capacity);

1292

842

if(buffer_capacity == 0){

1293

843

int e = errno;

1294

844

perror_plus("incbuffer");

1321

871

}

1322

872

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

1323

873

if(ret < 0){

1324

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

1325

"***\n");

874

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

1326

875

gnutls_perror(ret);

1327

876

errno = EPROTO;

1328

877

goto mandos_end;

1329

878

}

1330

879

break;

1331

880

default:

1332

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

1333

" encrypted session with Mandos server\n");

881

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

882

" encrypted session with Mandos server\n");

1334

883

gnutls_bye(session, GNUTLS_SHUT_RDWR);

1335

884

errno = EIO;

1336

885

goto mandos_end;

1341

890

}

1342

891

1343

892

if(debug){

1344

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

893

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

1345

894

}

1346

895

1347

896

if(quit_now){

1359

908

1360

909

if(buffer_length > 0){

1361

910

ssize_t decrypted_buffer_size;

1362

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1363

&decrypted_buffer, mc);

911

decrypted_buffer_size = pgp_packet_decrypt(buffer,

912

buffer_length,

913

&decrypted_buffer);

1364

914

if(decrypted_buffer_size >= 0){

1365

915

1366

916

written = 0;

1376

926

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

1377

927

int e = errno;

1378

928

if(debug){

1379

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

1380

strerror(errno));

929

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

930

strerror(errno));

1381

931

}

1382

932

errno = e;

1383

933

goto mandos_end;

1392

942

1393

943

mandos_end:

1394

944

{

1395

if(route_added){

1396

if(not delete_local_route(ip, if_index)){

1397

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

1398

" interface %d", ip, if_index);

1399

}

1400

}

1401

945

int e = errno;

1402

946

free(decrypted_buffer);

1403

947

free(buffer);

1420

964

return retval;

1421

965

}

1422

966

1423

__attribute__((nonnull))

1424

967

static void resolve_callback(AvahiSServiceResolver *r,

1425

968

AvahiIfIndex interface,

1426

969

AvahiProtocol proto,

1434

977

AVAHI_GCC_UNUSED AvahiStringList *txt,

1435

978

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1436

979

flags,

1437

void *mc){

1438

if(r == NULL){

1439

return;

1440

}

980

AVAHI_GCC_UNUSED void* userdata){

981

assert(r);

1441

982

1442

983

/* Called whenever a service has been resolved successfully or

1443

984

timed out */

1444

985

1445

986

if(quit_now){

1446

avahi_s_service_resolver_free(r);

1447

987

return;

1448

988

}

1449

989

1450

990

switch(event){

1451

991

default:

1452

992

case AVAHI_RESOLVER_FAILURE:

1453

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

1454

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

1455

domain,

1456

avahi_strerror(avahi_server_errno

1457

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

993

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

994

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

995

avahi_strerror(avahi_server_errno(mc.server)));

1458

996

break;

1459

997

1460

998

case AVAHI_RESOLVER_FOUND:

1462

1000

char ip[AVAHI_ADDRESS_STR_MAX];

1463

1001

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

1464

1002

if(debug){

1465

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

1466

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

1467

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

1003

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

1004

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

1005

ip, (intmax_t)interface, port);

1468

1006

}

1469

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

1470

interface,

1471

avahi_proto_to_af(proto),

1472

mc);

1007

int ret = start_mandos_communication(ip, port, interface,

1008

avahi_proto_to_af(proto));

1473

1009

if(ret == 0){

1474

avahi_simple_poll_quit(simple_poll);

1010

avahi_simple_poll_quit(mc.simple_poll);

1475

1011

} else {

1476

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

1477

avahi_proto_to_af(proto),

1478

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

1479

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

1480

" list\n", name);

1481

}

1012

ret = add_server(ip, port, interface,

1013

avahi_proto_to_af(proto));

1482

1014

}

1483

1015

}

1484

1016

}

1494

1026

const char *domain,

1495

1027

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1496

1028

flags,

1497

void *mc){

1498

if(b == NULL){

1499

return;

1500

}

1029

AVAHI_GCC_UNUSED void* userdata){

1030

assert(b);

1501

1031

1502

1032

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

1503

1033

is removed from the LAN */

1510

1040

default:

1511

1041

case AVAHI_BROWSER_FAILURE:

1512

1042

1513

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

1514

avahi_strerror(avahi_server_errno

1515

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

1516

avahi_simple_poll_quit(simple_poll);

1043

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

1044

avahi_strerror(avahi_server_errno(mc.server)));

1045

avahi_simple_poll_quit(mc.simple_poll);

1517

1046

return;

1518

1047

1519

1048

case AVAHI_BROWSER_NEW:

1522

1051

the callback function is called the Avahi server will free the

1523

1052

resolver for us. */

1524

1053

1525

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

1526

interface, protocol, name, type,

1527

domain, protocol, 0,

1528

resolve_callback, mc) == NULL)

1529

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

1530

" %s\n", name,

1531

avahi_strerror(avahi_server_errno

1532

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

1054

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

1055

name, type, domain, protocol, 0,

1056

resolve_callback, NULL) == NULL)

1057

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

1058

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

1533

1059

break;

1534

1060

1535

1061

case AVAHI_BROWSER_REMOVE:

1538

1064

case AVAHI_BROWSER_ALL_FOR_NOW:

1539

1065

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1540

1066

if(debug){

1541

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

1542

" searching...\n");

1067

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

1543

1068

}

1544

1069

break;

1545

1070

}

1554

1079

signal_received = sig;

1555

1080

int old_errno = errno;

1556

1081

/* set main loop to exit */

1557

if(simple_poll != NULL){

1558

avahi_simple_poll_quit(simple_poll);

1082

if(mc.simple_poll != NULL){

1083

avahi_simple_poll_quit(mc.simple_poll);

1559

1084

}

1560

1085

errno = old_errno;

1561

1086

}

1562

1087

1563

__attribute__((nonnull, warn_unused_result))

1564

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

1565

int ret;

1566

error_t ret_errno;

1567

1568

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

1569

if(s < 0){

1570

ret_errno = errno;

1571

perror_plus("socket");

1572

errno = ret_errno;

1573

return false;

1574

}

1575

strcpy(ifr->ifr_name, ifname);

1576

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1577

if(ret == -1){

1088

/*

1089

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

1090

* corresponds to an acceptable network device.

1091

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

1092

*/

1093

int good_interface(const struct dirent *if_entry){

1094

ssize_t ssret;

1095

char *flagname = NULL;

1096

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

1097

return 0;

1098

}

1099

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

1100

if_entry->d_name);

1101

if(ret < 0){

1102

perror_plus("asprintf");

1103

return 0;

1104

}

1105

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

1106

if(flags_fd == -1){

1107

perror_plus("open");

1108

free(flagname);

1109

return 0;

1110

}

1111

free(flagname);

1112

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

1113

/* read line from flags_fd */

1114

ssize_t to_read = 2+(sizeof(ifreq_flags)*2)+1; /* "0x1003\n" */

1115

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

1116

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

1117

if(flagstring == NULL){

1118

perror_plus("malloc");

1119

close(flags_fd);

1120

return 0;

1121

}

1122

while(to_read > 0){

1123

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

1124

(size_t)to_read));

1125

if(ssret == -1){

1126

perror_plus("read");

1127

free(flagstring);

1128

close(flags_fd);

1129

return 0;

1130

}

1131

to_read -= ssret;

1132

if(ssret == 0){

1133

break;

1134

}

1135

}

1136

close(flags_fd);

1137

intmax_t tmpmax;

1138

char *tmp;

1139

errno = 0;

1140

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

1141

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

1142

and not (isspace(*tmp)))

1143

or tmpmax != (ifreq_flags)tmpmax){

1578

1144

if(debug){

1579

ret_errno = errno;

1580

perror_plus("ioctl SIOCGIFFLAGS");

1581

errno = ret_errno;

1145

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

1146

flagstring, if_entry->d_name);

1582

1147

}

1583

return false;

1148

free(flagstring);

1149

return 0;

1584

1150

}

1585

return true;

1586

}

1587

1588

__attribute__((nonnull, warn_unused_result))

1589

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

1590

1151

free(flagstring);

1152

ifreq_flags flags = (ifreq_flags)tmpmax;

1591

1153

/* Reject the loopback device */

1592

if(ifr->ifr_flags & IFF_LOOPBACK){

1154

if(flags & IFF_LOOPBACK){

1593

1155

if(debug){

1594

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

1595

ifname);

1156

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

1157

if_entry->d_name);

1596

1158

}

1597

return false;

1159

return 0;

1598

1160

}

1599

1161

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

1600

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

1162

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

1601

1163

if(debug){

1602

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

1603

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

1164

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

1165

if_entry->d_name);

1604

1166

}

1605

return true;

1167

return 1;

1606

1168

}

1607

1169

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

1608

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

1170

if(not (flags & IFF_BROADCAST)){

1609

1171

if(debug){

1610

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1611

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

1172

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

1173

if_entry->d_name);

1612

1174

}

1613

return false;

1175

return 0;

1614

1176

}

1615

1177

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

1616

if(ifr->ifr_flags & IFF_NOARP){

1178

if(flags & IFF_NOARP){

1617

1179

if(debug){

1618

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

1619

ifname);

1180

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

1181

if_entry->d_name);

1620

1182

}

1621

return false;

1183

return 0;

1622

1184

}

1623

1624

1185

/* Accept this device */

1625

1186

if(debug){

1626

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

1627

}

1628

return true;

1629

}

1630

1631

/*

1632

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

1633

* corresponds to an acceptable network device.

1634

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

1635

*/

1636

__attribute__((nonnull, warn_unused_result))

1637

int good_interface(const struct dirent *if_entry){

1638

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

1639

return 0;

1640

}

1641

1642

struct ifreq ifr;

1643

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

1644

if(debug){

1645

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

1646

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

1647

}

1648

return 0;

1649

}

1650

1651

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

1652

return 0;

1187

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

1188

if_entry->d_name);

1653

1189

}

1654

1190

return 1;

1655

1191

}

1656

1192

1657

/*

1658

* This function determines if a network interface is up.

1659

*/

1660

__attribute__((nonnull, warn_unused_result))

1661

bool interface_is_up(const char *interface){

1662

struct ifreq ifr;

1663

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

1664

if(debug){

1665

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

1666

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

1667

}

1668

return false;

1669

}

1670

1671

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

1672

}

1673

1674

/*

1675

* This function determines if a network interface is running

1676

*/

1677

__attribute__((nonnull, warn_unused_result))

1678

bool interface_is_running(const char *interface){

1679

struct ifreq ifr;

1680

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

1681

if(debug){

1682

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

1683

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

1684

}

1685

return false;

1686

}

1687

1688

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

1689

}

1690

1691

__attribute__((nonnull, pure, warn_unused_result))

1692

1193

int notdotentries(const struct dirent *direntry){

1693

1194

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

1694

1195

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

1700

1201

return 1;

1701

1202

}

1702

1203

1703

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

1704

__attribute__((nonnull, warn_unused_result))

1705

int runnable_hook(const struct dirent *direntry){

1706

int ret;

1707

size_t sret;

1708

struct stat st;

1709

1710

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

1711

/* Empty name? */

1712

return 0;

1713

}

1714

1715

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

1716

"abcdefghijklmnopqrstuvwxyz"

1717

"0123456789"

1718

"_.-");

1719

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

1720

/* Contains non-allowed characters */

1721

if(debug){

1722

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

1723

direntry->d_name);

1724

}

1725

return 0;

1726

}

1727

1728

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

1729

if(ret == -1){

1730

if(debug){

1731

perror_plus("Could not stat hook");

1732

}

1733

return 0;

1734

}

1735

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

1736

/* Not a regular file */

1737

if(debug){

1738

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

1739

direntry->d_name);

1740

}

1741

return 0;

1742

}

1743

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

1744

/* Not executable */

1745

if(debug){

1746

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

1747

direntry->d_name);

1748

}

1749

return 0;

1750

}

1751

if(debug){

1752

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

1753

direntry->d_name);

1754

}

1755

return 1;

1756

}

1757

1758

__attribute__((nonnull, warn_unused_result))

1759

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1760

mandos_context *mc){

1204

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1761

1205

int ret;

1762

1206

struct timespec now;

1763

1207

struct timespec waited_time;

1764

1208

intmax_t block_time;

1765

1209

1766

1210

while(true){

1767

if(mc->current_server == NULL){

1768

if(debug){

1769

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

1770

" No timeout!\n");

1211

if(mc.current_server == NULL){

1212

if (debug){

1213

fprintf(stderr,

1214

"Wait until first server is found. No timeout!\n");

1771

1215

}

1772

1216

ret = avahi_simple_poll_iterate(s, -1);

1773

1217

} else {

1774

if(debug){

1775

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

1776

" it, or wait\n");

1218

if (debug){

1219

fprintf(stderr, "Check current_server if we should run it,"

1220

" or wait\n");

1777

1221

}

1778

1222

/* the current time */

1779

1223

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1784

1228

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

1785

1229

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

1786

1230

waited_time.tv_sec = (now.tv_sec

1787

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

1231

- mc.current_server->last_seen.tv_sec);

1788

1232

waited_time.tv_nsec = (now.tv_nsec

1789

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

1233

- mc.current_server->last_seen.tv_nsec);

1790

1234

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

1791

1235

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

1792

1236

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

1794

1238

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

1795

1239

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

1796

1240

1797

if(debug){

1798

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

1799

block_time);

1241

if (debug){

1242

fprintf(stderr, "Blocking for %" PRIdMAX " ms\n", block_time);

1800

1243

}

1801

1244

1802

1245

if(block_time <= 0){

1803

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

1804

mc->current_server->port,

1805

mc->current_server->if_index,

1806

mc->current_server->af, mc);

1246

ret = start_mandos_communication(mc.current_server->ip,

1247

mc.current_server->port,

1248

mc.current_server->if_index,

1249

mc.current_server->af);

1807

1250

if(ret == 0){

1808

avahi_simple_poll_quit(s);

1251

avahi_simple_poll_quit(mc.simple_poll);

1809

1252

return 0;

1810

1253

}

1811

1254

ret = clock_gettime(CLOCK_MONOTONIC,

1812

&mc->current_server->last_seen);

1255

&mc.current_server->last_seen);

1813

1256

if(ret == -1){

1814

1257

perror_plus("clock_gettime");

1815

1258

return -1;

1816

1259

}

1817

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

1260

mc.current_server = mc.current_server->next;

1818

1261

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

1819

1262

servers, but don't block */

1820

1263

}

1822

1265

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

1823

1266

}

1824

1267

if(ret != 0){

1825

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

1268

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

1826

1269

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

1827

1270

}

1828

1271

}

1829

1272

}

1830

1273

}

1831

1274

1832

__attribute__((nonnull))

1833

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

1834

const float delay){

1835

struct dirent **direntries = NULL;

1836

if(hookdir_fd == -1){

1837

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1838

| O_CLOEXEC);

1839

if(hookdir_fd == -1){

1840

if(errno == ENOENT){

1841

if(debug){

1842

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

1843

" found\n", hookdir);

1844

}

1845

} else {

1846

perror_plus("open");

1847

}

1848

return;

1849

}

1850

}

1851

#ifdef __GLIBC__

1852

#if __GLIBC_PREREQ(2, 15)

1853

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

1854

runnable_hook, alphasort);

1855

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

1856

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

1857

alphasort);

1858

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

1859

#else /* not __GLIBC__ */

1860

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

1861

alphasort);

1862

#endif /* not __GLIBC__ */

1863

if(numhooks == -1){

1864

perror_plus("scandir");

1865

return;

1866

}

1867

struct dirent *direntry;

1868

int ret;

1869

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

1870

if(devnull == -1){

1871

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

1872

return;

1873

}

1874

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

1875

direntry = direntries[i];

1876

if(debug){

1877

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

1878

direntry->d_name);

1879

}

1880

pid_t hook_pid = fork();

1881

if(hook_pid == 0){

1882

/* Child */

1883

/* Raise privileges */

1884

errno = raise_privileges_permanently();

1885

if(errno != 0){

1886

perror_plus("Failed to raise privileges");

1887

_exit(EX_NOPERM);

1888

}

1889

/* Set group */

1890

errno = 0;

1891

ret = setgid(0);

1892

if(ret == -1){

1893

perror_plus("setgid");

1894

_exit(EX_NOPERM);

1895

}

1896

/* Reset supplementary groups */

1897

errno = 0;

1898

ret = setgroups(0, NULL);

1899

if(ret == -1){

1900

perror_plus("setgroups");

1901

_exit(EX_NOPERM);

1902

}

1903

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

1904

if(ret == -1){

1905

perror_plus("setenv");

1906

_exit(EX_OSERR);

1907

}

1908

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

1909

if(ret == -1){

1910

perror_plus("setenv");

1911

_exit(EX_OSERR);

1912

}

1913

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

1914

if(ret == -1){

1915

perror_plus("setenv");

1916

_exit(EX_OSERR);

1917

}

1918

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

1919

if(ret == -1){

1920

perror_plus("setenv");

1921

_exit(EX_OSERR);

1922

}

1923

char *delaystring;

1924

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

1925

if(ret == -1){

1926

perror_plus("asprintf");

1927

_exit(EX_OSERR);

1928

}

1929

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

1930

if(ret == -1){

1931

free(delaystring);

1932

perror_plus("setenv");

1933

_exit(EX_OSERR);

1934

}

1935

free(delaystring);

1936

if(connect_to != NULL){

1937

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

1938

if(ret == -1){

1939

perror_plus("setenv");

1940

_exit(EX_OSERR);

1941

}

1942

}

1943

int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,

1944

direntry->d_name,

1945

O_RDONLY));

1946

if(hook_fd == -1){

1947

perror_plus("openat");

1948

_exit(EXIT_FAILURE);

1949

}

1950

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

1951

perror_plus("close");

1952

_exit(EXIT_FAILURE);

1953

}

1954

ret = dup2(devnull, STDIN_FILENO);

1955

if(ret == -1){

1956

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

1957

_exit(EX_OSERR);

1958

}

1959

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

1960

if(ret == -1){

1961

perror_plus("close");

1962

_exit(EX_OSERR);

1963

}

1964

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1965

if(ret == -1){

1966

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

1967

_exit(EX_OSERR);

1968

}

1969

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

1970

environ) == -1){

1971

perror_plus("fexecve");

1972

_exit(EXIT_FAILURE);

1973

}

1974

} else {

1975

if(hook_pid == -1){

1976

perror_plus("fork");

1977

free(direntry);

1978

continue;

1979

}

1980

int status;

1981

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

1982

perror_plus("waitpid");

1983

free(direntry);

1984

continue;

1985

}

1986

if(WIFEXITED(status)){

1987

if(WEXITSTATUS(status) != 0){

1988

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

1989

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

1990

WEXITSTATUS(status));

1991

free(direntry);

1992

continue;

1993

}

1994

} else if(WIFSIGNALED(status)){

1995

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

1996

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

1997

WTERMSIG(status));

1998

free(direntry);

1999

continue;

2000

} else {

2001

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

2002

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

2003

free(direntry);

2004

continue;

2005

}

2006

}

2007

if(debug){

2008

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

2009

direntry->d_name);

2010

}

2011

free(direntry);

2012

}

2013

free(direntries);

2014

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

2015

perror_plus("close");

2016

} else {

2017

hookdir_fd = -1;

2018

}

2019

close(devnull);

2020

}

2021

2022

__attribute__((nonnull, warn_unused_result))

2023

error_t bring_up_interface(const char *const interface,

2024

const float delay){

2025

error_t old_errno = errno;

2026

int ret;

2027

struct ifreq network;

2028

unsigned int if_index = if_nametoindex(interface);

2029

if(if_index == 0){

2030

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

2031

errno = old_errno;

2032

return ENXIO;

2033

}

2034

2035

if(quit_now){

2036

errno = old_errno;

2037

return EINTR;

2038

}

2039

2040

if(not interface_is_up(interface)){

2041

error_t ret_errno = 0, ioctl_errno = 0;

2042

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

2043

ret_errno = errno;

2044

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

2045

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

2046

errno = old_errno;

2047

return ret_errno;

2048

}

2049

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

2050

2051

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

2052

if(sd == -1){

2053

ret_errno = errno;

2054

perror_plus("socket");

2055

errno = old_errno;

2056

return ret_errno;

2057

}

2058

2059

if(quit_now){

2060

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

2061

if(ret == -1){

2062

perror_plus("close");

2063

}

2064

errno = old_errno;

2065

return EINTR;

2066

}

2067

2068

if(debug){

2069

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

2070

interface);

2071

}

2072

2073

/* Raise privileges */

2074

ret_errno = raise_privileges();

2075

if(ret_errno != 0){

2076

errno = ret_errno;

2077

perror_plus("Failed to raise privileges");

2078

}

2079

2080

#ifdef __linux__

2081

int ret_linux;

2082

bool restore_loglevel = false;

2083

if(ret_errno == 0){

2084

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2085

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

2086

ret_linux = klogctl(8, NULL, 5);

2087

if(ret_linux == -1){

2088

perror_plus("klogctl");

2089

} else {

2090

restore_loglevel = true;

2091

}

2092

}

2093

#endif /* __linux__ */

2094

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

2095

ioctl_errno = errno;

2096

#ifdef __linux__

2097

if(restore_loglevel){

2098

ret_linux = klogctl(7, NULL, 0);

2099

if(ret_linux == -1){

2100

perror_plus("klogctl");

2101

}

2102

}

2103

#endif /* __linux__ */

2104

2105

/* If raise_privileges() succeeded above */

2106

if(ret_errno == 0){

2107

/* Lower privileges */

2108

ret_errno = lower_privileges();

2109

if(ret_errno != 0){

2110

errno = ret_errno;

2111

perror_plus("Failed to lower privileges");

2112

}

2113

}

2114

2115

/* Close the socket */

2116

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

2117

if(ret == -1){

2118

perror_plus("close");

2119

}

2120

2121

if(ret_setflags == -1){

2122

errno = ioctl_errno;

2123

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2124

errno = old_errno;

2125

return ioctl_errno;

2126

}

2127

} else if(debug){

2128

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

2129

interface);

2130

}

2131

2132

/* Sleep checking until interface is running.

2133

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

2134

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

2135

if(interface_is_running(interface)){

2136

break;

2137

}

2138

struct timespec sleeptime = { .tv_nsec = 250000000 };

2139

ret = nanosleep(&sleeptime, NULL);

2140

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

2141

perror_plus("nanosleep");

2142

}

2143

}

2144

2145

errno = old_errno;

2146

return 0;

2147

}

2148

2149

__attribute__((nonnull, warn_unused_result))

2150

error_t take_down_interface(const char *const interface){

2151

error_t old_errno = errno;

2152

struct ifreq network;

2153

unsigned int if_index = if_nametoindex(interface);

2154

if(if_index == 0){

2155

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

2156

errno = old_errno;

2157

return ENXIO;

2158

}

2159

if(interface_is_up(interface)){

2160

error_t ret_errno = 0, ioctl_errno = 0;

2161

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

2162

ret_errno = errno;

2163

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

2164

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

2165

errno = old_errno;

2166

return ret_errno;

2167

}

2168

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

2169

2170

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

2171

if(sd == -1){

2172

ret_errno = errno;

2173

perror_plus("socket");

2174

errno = old_errno;

2175

return ret_errno;

2176

}

2177

2178

if(debug){

2179

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

2180

interface);

2181

}

2182

2183

/* Raise privileges */

2184

ret_errno = raise_privileges();

2185

if(ret_errno != 0){

2186

errno = ret_errno;

2187

perror_plus("Failed to raise privileges");

2188

}

2189

2190

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

2191

ioctl_errno = errno;

2192

2193

/* If raise_privileges() succeeded above */

2194

if(ret_errno == 0){

2195

/* Lower privileges */

2196

ret_errno = lower_privileges();

2197

if(ret_errno != 0){

2198

errno = ret_errno;

2199

perror_plus("Failed to lower privileges");

2200

}

2201

}

2202

2203

/* Close the socket */

2204

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

2205

if(ret == -1){

2206

perror_plus("close");

2207

}

2208

2209

if(ret_setflags == -1){

2210

errno = ioctl_errno;

2211

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2212

errno = old_errno;

2213

return ioctl_errno;

2214

}

2215

} else if(debug){

2216

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

2217

interface);

2218

}

2219

2220

errno = old_errno;

2221

return 0;

2222

}

2223

2224

1275

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

2225

mandos_context mc = { .server = NULL, .dh_bits = 0,

2226

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

2227

"+CTYPE-OPENPGP:!RSA", .current_server = NULL,

2228

.interfaces = NULL, .interfaces_size = 0 };

2229

1276

AvahiSServiceBrowser *sb = NULL;

2230

error_t ret_errno;

1277

int error;

2231

1278

int ret;

2232

1279

intmax_t tmpmax;

2233

1280

char *tmp;

2234

1281

int exitcode = EXIT_SUCCESS;

2235

char *interfaces_to_take_down = NULL;

2236

size_t interfaces_to_take_down_size = 0;

2237

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

2238

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

2239

char *tempdir = NULL;

1282

const char *interface = "";

1283

struct ifreq network;

1284

int sd = -1;

1285

bool take_down_interface = false;

1286

uid_t uid;

1287

gid_t gid;

1288

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

1289

bool tempdir_created = false;

2240

1290

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2241

1291

const char *seckey = PATHDIR "/" SECKEY;

2242

1292

const char *pubkey = PATHDIR "/" PUBKEY;

2243

char *interfaces_hooks = NULL;

2244

1293

2245

1294

bool gnutls_initialized = false;

2246

1295

bool gpgme_initialized = false;

2308

1357

.group = 2 },

2309

1358

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

2310

1359

.arg = "SECONDS",

2311

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

2312

.group = 2 },

2313

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

2314

.arg = "DIR",

2315

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

1360

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

2316

1361

.group = 2 },

2317

1362

/*

2318

1363

* These reproduce what we would get without ARGP_NO_HELP

2337

1382

connect_to = arg;

2338

1383

break;

2339

1384

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

2340

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

2341

arg, (int)',');

2342

if(ret_errno != 0){

2343

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

2344

}

1385

interface = arg;

2345

1386

break;

2346

1387

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

2347

1388

seckey = arg;

2376

1417

argp_error(state, "Bad retry interval");

2377

1418

}

2378

1419

break;

2379

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

2380

hookdir = arg;

2381

break;

2382

1420

/*

2383

1421

* These reproduce what we would get without ARGP_NO_HELP

2384

1422

*/

2390

1428

argp_state_help(state, state->out_stream,

2391

1429

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2392

1430

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

2393

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

1431

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

2394

1432

exit(argp_err_exit_status);

2395

1433

break;

2396

1434

default:

2419

1457

goto end;

2420

1458

}

2421

1459

}

2422

1460

2423

1461

{

2424

1462

/* Work around Debian bug #633582:

2425

1463

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

2426

2427

/* Re-raise privileges */

2428

ret_errno = raise_privileges();

2429

if(ret_errno != 0){

2430

errno = ret_errno;

2431

perror_plus("Failed to raise privileges");

2432

} else {

2433

struct stat st;

2434

2435

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

2436

int seckey_fd = open(seckey, O_RDONLY);

2437

if(seckey_fd == -1){

2438

perror_plus("open");

2439

} else {

2440

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

2441

if(ret == -1){

2442

perror_plus("fstat");

2443

} else {

2444

if(S_ISREG(st.st_mode)

2445

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

2446

ret = fchown(seckey_fd, uid, gid);

2447

if(ret == -1){

2448

perror_plus("fchown");

2449

}

2450

}

2451

}

2452

TEMP_FAILURE_RETRY(close(seckey_fd));

2453

}

2454

}

2455

2456

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

2457

int pubkey_fd = open(pubkey, O_RDONLY);

2458

if(pubkey_fd == -1){

2459

perror_plus("open");

2460

} else {

2461

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

2462

if(ret == -1){

2463

perror_plus("fstat");

2464

} else {

2465

if(S_ISREG(st.st_mode)

2466

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

2467

ret = fchown(pubkey_fd, uid, gid);

2468

if(ret == -1){

2469

perror_plus("fchown");

2470

}

2471

}

2472

}

2473

TEMP_FAILURE_RETRY(close(pubkey_fd));

2474

}

2475

}

2476

2477

/* Lower privileges */

2478

ret_errno = lower_privileges();

2479

if(ret_errno != 0){

2480

errno = ret_errno;

2481

perror_plus("Failed to lower privileges");

2482

}

2483

}

2484

}

2485

2486

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

2487

{

2488

char *interface = NULL;

2489

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

2490

interface))){

2491

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

2492

and if_nametoindex(interface) == 0){

2493

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

2494

fprintf_plus(stderr, "Not using nonexisting interface"

2495

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

2496

}

2497

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

2498

interface = NULL;

2499

}

2500

}

2501

}

2502

2503

/* Run network hooks */

2504

{

2505

if(mc.interfaces != NULL){

2506

interfaces_hooks = malloc(mc.interfaces_size);

2507

if(interfaces_hooks == NULL){

2508

perror_plus("malloc");

2509

goto end;

2510

}

2511

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

2512

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

2513

}

2514

run_network_hooks("start", interfaces_hooks != NULL ?

2515

interfaces_hooks : "", delay);

1464

struct stat st;

1465

1466

/* Re-raise priviliges */

1467

errno = 0;

1468

ret = seteuid(0);

1469

if(ret == -1){

1470

perror_plus("seteuid");

1471

}

1472

1473

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

1474

int seckey_fd = open(seckey, O_RDONLY);

1475

if(seckey_fd == -1){

1476

perror_plus("open");

1477

} else {

1478

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

1479

if(ret == -1){

1480

perror_plus("fstat");

1481

} else {

1482

if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){

1483

ret = fchown(seckey_fd, uid, gid);

1484

if(ret == -1){

1485

perror_plus("fchown");

1486

}

1487

}

1488

}

1489

TEMP_FAILURE_RETRY(close(seckey_fd));

1490

}

1491

}

1492

1493

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

1494

int pubkey_fd = open(pubkey, O_RDONLY);

1495

if(pubkey_fd == -1){

1496

perror_plus("open");

1497

} else {

1498

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

1499

if(ret == -1){

1500

perror_plus("fstat");

1501

} else {

1502

if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){

1503

ret = fchown(pubkey_fd, uid, gid);

1504

if(ret == -1){

1505

perror_plus("fchown");

1506

}

1507

}

1508

}

1509

TEMP_FAILURE_RETRY(close(pubkey_fd));

1510

}

1511

}

1512

1513

/* Lower privileges */

1514

errno = 0;

1515

ret = seteuid(uid);

1516

if(ret == -1){

1517

perror_plus("seteuid");

1518

}

2516

1519

}

2517

1520

2518

1521

if(not debug){

2519

1522

avahi_set_log_function(empty_log);

2520

1523

}

1524

1525

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

1526

struct dirent **direntries;

1527

ret = scandir(sys_class_net, &direntries, good_interface,

1528

alphasort);

1529

if(ret >= 1){

1530

/* Pick the first good interface */

1531

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

1532

if(debug){

1533

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

1534

}

1535

if(interface == NULL){

1536

perror_plus("malloc");

1537

free(direntries);

1538

exitcode = EXIT_FAILURE;

1539

goto end;

1540

}

1541

free(direntries);

1542

} else {

1543

free(direntries);

1544

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

1545

exitcode = EXIT_FAILURE;

1546

goto end;

1547

}

1548

}

2521

1549

2522

1550

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

2523

1551

from the signal handler */

2524

1552

/* Initialize the pseudo-RNG for Avahi */

2525

1553

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

2526

simple_poll = avahi_simple_poll_new();

2527

if(simple_poll == NULL){

2528

fprintf_plus(stderr,

2529

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

1554

mc.simple_poll = avahi_simple_poll_new();

1555

if(mc.simple_poll == NULL){

1556

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

2530

1557

exitcode = EX_UNAVAILABLE;

2531

1558

goto end;

2532

1559

}

2594

1621

}

2595

1622

}

2596

1623

2597

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

2598

if(mc.interfaces == NULL){

2599

struct dirent **direntries = NULL;

2600

/* Look for any good interfaces */

2601

ret = scandir(sys_class_net, &direntries, good_interface,

2602

alphasort);

2603

if(ret >= 1){

2604

/* Add all found interfaces to interfaces list */

2605

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

2606

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

2607

direntries[i]->d_name);

2608

if(ret_errno != 0){

2609

errno = ret_errno;

2610

perror_plus("argz_add");

2611

free(direntries[i]);

2612

continue;

2613

}

2614

if(debug){

2615

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

2616

direntries[i]->d_name);

2617

}

2618

free(direntries[i]);

2619

}

2620

free(direntries);

1624

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

1625

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

1626

if_index = (AvahiIfIndex) if_nametoindex(interface);

1627

if(if_index == 0){

1628

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

1629

exitcode = EX_UNAVAILABLE;

1630

goto end;

1631

}

1632

1633

if(quit_now){

1634

goto end;

1635

}

1636

1637

/* Re-raise priviliges */

1638

errno = 0;

1639

ret = seteuid(0);

1640

if(ret == -1){

1641

perror_plus("seteuid");

1642

}

1643

1644

#ifdef __linux__

1645

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1646

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

1647

ret = klogctl(8, NULL, 5);

1648

bool restore_loglevel = true;

1649

if(ret == -1){

1650

restore_loglevel = false;

1651

perror_plus("klogctl");

1652

}

1653

#endif /* __linux__ */

1654

1655

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1656

if(sd < 0){

1657

perror_plus("socket");

1658

exitcode = EX_OSERR;

1659

#ifdef __linux__

1660

if(restore_loglevel){

1661

ret = klogctl(7, NULL, 0);

1662

if(ret == -1){

1663

perror_plus("klogctl");

1664

}

1665

}

1666

#endif /* __linux__ */

1667

/* Lower privileges */

1668

errno = 0;

1669

ret = seteuid(uid);

1670

if(ret == -1){

1671

perror_plus("seteuid");

1672

}

1673

goto end;

1674

}

1675

strcpy(network.ifr_name, interface);

1676

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

1677

if(ret == -1){

1678

perror_plus("ioctl SIOCGIFFLAGS");

1679

#ifdef __linux__

1680

if(restore_loglevel){

1681

ret = klogctl(7, NULL, 0);

1682

if(ret == -1){

1683

perror_plus("klogctl");

1684

}

1685

}

1686

#endif /* __linux__ */

1687

exitcode = EX_OSERR;

1688

/* Lower privileges */

1689

errno = 0;

1690

ret = seteuid(uid);

1691

if(ret == -1){

1692

perror_plus("seteuid");

1693

}

1694

goto end;

1695

}

1696

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

1697

network.ifr_flags |= IFF_UP;

1698

take_down_interface = true;

1699

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

1700

if(ret == -1){

1701

take_down_interface = false;

1702

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1703

exitcode = EX_OSERR;

1704

#ifdef __linux__

1705

if(restore_loglevel){

1706

ret = klogctl(7, NULL, 0);

1707

if(ret == -1){

1708

perror_plus("klogctl");

1709

}

1710

}

1711

#endif /* __linux__ */

1712

/* Lower privileges */

1713

errno = 0;

1714

ret = seteuid(uid);

1715

if(ret == -1){

1716

perror_plus("seteuid");

1717

}

1718

goto end;

1719

}

1720

}

1721

/* Sleep checking until interface is running.

1722

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

1723

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

1724

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

1725

if(ret == -1){

1726

perror_plus("ioctl SIOCGIFFLAGS");

1727

} else if(network.ifr_flags & IFF_RUNNING){

1728

break;

1729

}

1730

struct timespec sleeptime = { .tv_nsec = 250000000 };

1731

ret = nanosleep(&sleeptime, NULL);

1732

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

1733

perror_plus("nanosleep");

1734

}

1735

}

1736

if(not take_down_interface){

1737

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

1738

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

1739

if(ret == -1){

1740

perror_plus("close");

1741

}

1742

}

1743

#ifdef __linux__

1744

if(restore_loglevel){

1745

/* Restores kernel loglevel to default */

1746

ret = klogctl(7, NULL, 0);

1747

if(ret == -1){

1748

perror_plus("klogctl");

1749

}

1750

}

1751

#endif /* __linux__ */

1752

/* Lower privileges */

1753

errno = 0;

1754

if(take_down_interface){

1755

/* Lower privileges */

1756

ret = seteuid(uid);

1757

if(ret == -1){

1758

perror_plus("seteuid");

1759

}

2621

1760

} else {

2622

if(ret == 0){

2623

free(direntries);

2624

}

2625

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

2626

exitcode = EXIT_FAILURE;

2627

goto end;

2628

}

2629

}

2630

2631

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

2632

{

2633

char *interface = NULL;

2634

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

2635

interface))){

2636

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

2637

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

2638

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

2639

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

2640

interface);

2641

interface = NULL;

2642

while((interface = argz_next(mc.interfaces,

2643

mc.interfaces_size, interface))){

2644

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

2645

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

2646

interface);

2647

interface = NULL;

2648

}

2649

}

2650

break;

2651

}

2652

bool interface_was_up = interface_is_up(interface);

2653

errno = bring_up_interface(interface, delay);

2654

if(not interface_was_up){

2655

if(errno != 0){

2656

perror_plus("Failed to bring up interface");

2657

} else {

2658

errno = argz_add(&interfaces_to_take_down,

2659

&interfaces_to_take_down_size,

2660

interface);

2661

if(errno != 0){

2662

perror_plus("argz_add");

2663

}

2664

}

2665

}

2666

}

2667

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

2668

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

2669

}

2670

}

2671

2672

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

2673

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

2674

if(debug){

2675

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

2676

mc.interfaces);

2677

}

2678

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

1761

/* Lower privileges permanently */

1762

ret = setuid(uid);

1763

if(ret == -1){

1764

perror_plus("setuid");

1765

}

1766

}

2679

1767

}

2680

1768

2681

1769

if(quit_now){

2682

1770

goto end;

2683

1771

}

2684

1772

2685

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

1773

ret = init_gnutls_global(pubkey, seckey);

2686

1774

if(ret == -1){

2687

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

1775

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

2688

1776

exitcode = EX_UNAVAILABLE;

2689

1777

goto end;

2690

1778

} else {

2695

1783

goto end;

2696

1784

}

2697

1785

2698

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

2699

tempdir = mkdtemp(run_tempdir);

2700

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

2701

if(debug){

2702

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

2703

run_tempdir, old_tempdir);

2704

}

2705

tempdir = mkdtemp(old_tempdir);

2706

}

2707

if(tempdir == NULL){

1786

if(mkdtemp(tempdir) == NULL){

2708

1787

perror_plus("mkdtemp");

2709

1788

goto end;

2710

1789

}

1790

tempdir_created = true;

2711

1791

2712

1792

if(quit_now){

2713

1793

goto end;

2714

1794

}

2715

1795

2716

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

2717

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

1796

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

1797

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

2718

1798

exitcode = EX_UNAVAILABLE;

2719

1799

goto end;

2720

1800

} else {

2729

1809

/* Connect directly, do not use Zeroconf */

2730

1810

/* (Mainly meant for debugging) */

2731

1811

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

2732

2733

1812

if(address == NULL){

2734

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

1813

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

2735

1814

exitcode = EX_USAGE;

2736

1815

goto end;

2737

1816

}

2740

1819

goto end;

2741

1820

}

2742

1821

2743

in_port_t port;

1822

uint16_t port;

2744

1823

errno = 0;

2745

1824

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

2746

1825

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

2747

or tmpmax != (in_port_t)tmpmax){

2748

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

1826

or tmpmax != (uint16_t)tmpmax){

1827

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

2749

1828

exitcode = EX_USAGE;

2750

1829

goto end;

2751

1830

}

2752

1831

2753

1832

if(quit_now){

2754

1833

goto end;

2755

1834

}

2756

1835

2757

port = (in_port_t)tmpmax;

1836

port = (uint16_t)tmpmax;

2758

1837

*address = '\0';

2759

1838

/* Colon in address indicates IPv6 */

2760

1839

int af;

2776

1855

}

2777

1856

2778

1857

while(not quit_now){

2779

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

2780

&mc);

1858

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

2781

1859

if(quit_now or ret == 0){

2782

1860

break;

2783

1861

}

2784

1862

if(debug){

2785

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

2786

(int)retry_interval);

1863

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

1864

(int)retry_interval);

2787

1865

}

2788

sleep((unsigned int)retry_interval);

1866

sleep((int)retry_interval);

2789

1867

}

2790

1868

2791

if(not quit_now){

1869

if (not quit_now){

2792

1870

exitcode = EXIT_SUCCESS;

2793

1871

}

2794

1872

2795

1873

goto end;

2796

1874

}

2797

1875

2809

1887

config.publish_domain = 0;

2810

1888

2811

1889

/* Allocate a new server */

2812

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2813

&config, NULL, NULL, &ret_errno);

1890

mc.server = avahi_server_new(avahi_simple_poll_get

1891

(mc.simple_poll), &config, NULL,

1892

NULL, &error);

2814

1893

2815

1894

/* Free the Avahi configuration data */

2816

1895

avahi_server_config_free(&config);

2818

1897

2819

1898

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

2820

1899

if(mc.server == NULL){

2821

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

2822

avahi_strerror(ret_errno));

1900

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

1901

avahi_strerror(error));

2823

1902

exitcode = EX_UNAVAILABLE;

2824

1903

goto end;

2825

1904

}

2831

1910

/* Create the Avahi service browser */

2832

1911

sb = avahi_s_service_browser_new(mc.server, if_index,

2833

1912

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2834

NULL, 0, browse_callback,

2835

(void *)&mc);

1913

NULL, 0, browse_callback, NULL);

2836

1914

if(sb == NULL){

2837

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

2838

avahi_strerror(avahi_server_errno(mc.server)));

1915

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

1916

avahi_strerror(avahi_server_errno(mc.server)));

2839

1917

exitcode = EX_UNAVAILABLE;

2840

1918

goto end;

2841

1919

}

2847

1925

/* Run the main loop */

2848

1926

2849

1927

if(debug){

2850

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

1928

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

2851

1929

}

2852

2853

ret = avahi_loop_with_timeout(simple_poll,

2854

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

1930

1931

ret = avahi_loop_with_timeout(mc.simple_poll,

1932

(int)(retry_interval * 1000));

2855

1933

if(debug){

2856

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

2857

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

1934

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

1935

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

2858

1936

}

2859

1937

2860

1938

end:

2861

1939

2862

1940

if(debug){

2863

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

1941

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

2864

1942

}

2865

1943

2866

1944

/* Cleanup things */

2867

free(mc.interfaces);

2868

2869

1945

if(sb != NULL)

2870

1946

avahi_s_service_browser_free(sb);

2871

1947

2872

1948

if(mc.server != NULL)

2873

1949

avahi_server_free(mc.server);

2874

1950

2875

if(simple_poll != NULL)

2876

avahi_simple_poll_free(simple_poll);

1951

if(mc.simple_poll != NULL)

1952

avahi_simple_poll_free(mc.simple_poll);

2877

1953

2878

1954

if(gnutls_initialized){

2879

1955

gnutls_certificate_free_credentials(mc.cred);

2884

1960

if(gpgme_initialized){

2885

1961

gpgme_release(mc.ctx);

2886

1962

}

2887

1963

2888

1964

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

2889

1965

has seen */

2890

1966

if(mc.current_server != NULL){

2891

1967

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

2892

1968

while(mc.current_server != NULL){

2893

1969

server *next = mc.current_server->next;

2894

#ifdef __GNUC__

2895

#pragma GCC diagnostic push

2896

#pragma GCC diagnostic ignored "-Wcast-qual"

2897

#endif

2898

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

2899

#ifdef __GNUC__

2900

#pragma GCC diagnostic pop

2901

#endif

2902

1970

free(mc.current_server);

2903

1971

mc.current_server = next;

2904

1972

}

2905

1973

}

2906

1974

2907

/* Re-raise privileges */

2908

{

2909

ret_errno = raise_privileges();

2910

if(ret_errno != 0){

2911

errno = ret_errno;

2912

perror_plus("Failed to raise privileges");

2913

} else {

2914

2915

/* Run network hooks */

2916

run_network_hooks("stop", interfaces_hooks != NULL ?

2917

interfaces_hooks : "", delay);

2918

2919

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

2920

{

2921

char *interface = NULL;

2922

while((interface=argz_next(interfaces_to_take_down,

2923

interfaces_to_take_down_size,

2924

interface))){

2925

ret_errno = take_down_interface(interface);

2926

if(ret_errno != 0){

2927

errno = ret_errno;

2928

perror_plus("Failed to take down interface");

2929

}

2930

}

2931

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

2932

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

2933

" down\n");

2934

}

2935

}

1975

/* Take down the network interface */

1976

if(take_down_interface){

1977

/* Re-raise priviliges */

1978

errno = 0;

1979

ret = seteuid(0);

1980

if(ret == -1){

1981

perror_plus("seteuid");

2936

1982

}

2937

2938

ret_errno = lower_privileges_permanently();

2939

if(ret_errno != 0){

2940

errno = ret_errno;

2941

perror_plus("Failed to lower privileges permanently");

1983

if(geteuid() == 0){

1984

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

1985

if(ret == -1){

1986

perror_plus("ioctl SIOCGIFFLAGS");

1987

} else if(network.ifr_flags & IFF_UP) {

1988

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

1989

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

1990

if(ret == -1){

1991

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1992

}

1993

}

1994

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

1995

if(ret == -1){

1996

perror_plus("close");

1997

}

1998

/* Lower privileges permanently */

1999

errno = 0;

2000

ret = setuid(uid);

2001

if(ret == -1){

2002

perror_plus("setuid");

2003

}

2942

2004

}

2943

2005

}

2944

2006

2945

free(interfaces_to_take_down);

2946

free(interfaces_hooks);

2947

2948

2007

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

2949

if(tempdir != NULL){

2008

if(tempdir_created){

2950

2009

struct dirent **direntries = NULL;

2951

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

2952

| O_NOFOLLOW

2953

| O_DIRECTORY

2954

| O_PATH));

2955

if(tempdir_fd == -1){

2956

perror_plus("open");

2957

} else {

2958

#ifdef __GLIBC__

2959

#if __GLIBC_PREREQ(2, 15)

2960

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

2961

notdotentries, alphasort);

2962

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

2963

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

2964

alphasort);

2965

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

2966

#else /* not __GLIBC__ */

2967

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

2968

alphasort);

2969

#endif /* not __GLIBC__ */

2970

if(numentries >= 0){

2971

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

2972

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

2973

if(ret == -1){

2974

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

2975

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

2976

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

2977

}

2978

free(direntries[i]);

2979

}

2980

2981

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

2982

free(direntries);

2983

if(numentries == -1){

2984

perror_plus("scandir");

2985

}

2986

ret = rmdir(tempdir);

2987

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

2988

perror_plus("rmdir");

2989

}

2010

struct dirent *direntry = NULL;

2011

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

2012

alphasort);

2013

if (numentries > 0){

2014

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

2015

direntry = direntries[i];

2016

char *fullname = NULL;

2017

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

2018

direntry->d_name);

2019

if(ret < 0){

2020

perror_plus("asprintf");

2021

continue;

2022

}

2023

ret = remove(fullname);

2024

if(ret == -1){

2025

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

2026

strerror(errno));

2027

}

2028

free(fullname);

2990

2029

}

2991

TEMP_FAILURE_RETRY(close(tempdir_fd));

2030

}

2031

2032

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

2033

free(direntries);

2034

if (numentries == -1){

2035

perror_plus("scandir");

2036

}

2037

ret = rmdir(tempdir);

2038

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

2039

perror_plus("rmdir");

2992

2040

}

2993

2041

}

2994

2042