/mandos/release : revision 24.1.179

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

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*

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* Everything else is

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*

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

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

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* along with this program. If not, see

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

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*

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

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

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*/

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

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#ifndef _LARGEFILE_SOURCE

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#define _LARGEFILE_SOURCE

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#endif /* not _LARGEFILE_SOURCE */

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#endif

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#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

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#endif /* not _FILE_OFFSET_BITS */

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#endif

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

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

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stdout, ferror() */

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

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stdout, ferror(), remove() */

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

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

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

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strtof(), abort() */

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sockaddr_in6, PF_INET6,

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SOCK_STREAM, uid_t, gid_t, open(),

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opendir(), DIR */

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

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

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

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inet_pton(), connect(),

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getnameinfo() */

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

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inet_pton(), connect() */

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

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

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*/

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

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strtoimax() */

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#include <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_version = "mandos-client " VERSION;

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

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

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

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char *connect_to = NULL;

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const char *hookdir = HOOKDIR;

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int hookdir_fd = -1;

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uid_t uid = 65534;

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gid_t gid = 65534;

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/* 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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unsigned int dh_bits;

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const char *priority;

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gpgme_ctx_t ctx;

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server *current_server;

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char *interfaces;

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size_t interfaces_size;

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} mandos_context;

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/* 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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171

}

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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: ",

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program_invocation_short_name));

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

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}

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198

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/*

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174

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

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

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* "buffer_length" is how much is already used.

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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);

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errno = old_errno;

212

*buffer = NULL;

181

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

182

if(buffer == NULL){

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183

return 0;

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184

}

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*buffer = new_buf;

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185

buffer_capacity += BUFFER_SIZE;

217

186

}

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return buffer_capacity;

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}

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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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int ret;

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

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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);

238

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));

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#ifdef __GNUC__

249

#pragma GCC diagnostic pop

250

#endif

251

free(new_server);

252

return false;

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return -1;

253

207

}

254

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/* 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;

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*current_server = new_server;

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mc.current_server = new_server;

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

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} else {

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

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new_server->next = *current_server;

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

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new_server->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;

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mc.current_server->prev = new_server;

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}

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

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if(ret == -1){

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perror_plus("clock_gettime");

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return -1;

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}

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return 0;

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}

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/*

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* Initialize GPGME.

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*/

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__attribute__((nonnull, warn_unused_result))

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static bool init_gpgme(const char * const seckey,

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const char * const pubkey,

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const char * const tempdir,

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mandos_context *mc){

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static bool init_gpgme(const char *seckey,

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const char *pubkey, const char *tempdir){

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gpgme_error_t rc;

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gpgme_engine_info_t engine_info;

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/*

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

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*/

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;

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int fd;

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gpgme_data_t pgp_data;

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rc = gpgme_data_new_from_fd(&pgp_data, fd);

295

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if(rc != GPG_ERR_NO_ERROR){

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

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}

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

258

rc = gpgme_op_import(mc.ctx, pgp_data);

302

259

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",

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gpgme_strsource(rc), gpgme_strerror(rc));

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262

return false;

306

263

}

307

264

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271

}

315

272

316

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if(debug){

317

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

274

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

318

275

}

319

276

320

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/* 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))

497

static const char *safer_gnutls_strerror(int value){

498

const char *ret = gnutls_strerror(value);

447

static const char * safer_gnutls_strerror(int value){

448

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

449

-Wunreachable-code */

499

450

if(ret == NULL)

500

451

ret = "(unknown)";

501

452

return ret;

502

453

}

503

454

504

455

/* GnuTLS log function callback */

505

__attribute__((nonnull))

506

456

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

507

457

const char* string){

508

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

458

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

509

459

}

510

460

511

__attribute__((nonnull, warn_unused_result))

512

461

static int init_gnutls_global(const char *pubkeyfilename,

513

const char *seckeyfilename,

514

mandos_context *mc){

462

const char *seckeyfilename){

515

463

int ret;

516

464

517

465

if(debug){

518

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

466

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

519

467

}

520

468

521

469

ret = gnutls_global_init();

522

470

if(ret != GNUTLS_E_SUCCESS){

523

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

524

safer_gnutls_strerror(ret));

471

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

472

safer_gnutls_strerror(ret));

525

473

return -1;

526

474

}

527

475

534

482

}

535

483

536

484

/* OpenPGP credentials */

537

ret = gnutls_certificate_allocate_credentials(&mc->cred);

485

ret = gnutls_certificate_allocate_credentials(&mc.cred);

538

486

if(ret != GNUTLS_E_SUCCESS){

539

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

540

safer_gnutls_strerror(ret));

487

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

488

safer_gnutls_strerror(ret));

541

489

gnutls_global_deinit();

542

490

return -1;

543

491

}

544

492

545

493

if(debug){

546

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

547

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

548

pubkeyfilename,

549

seckeyfilename);

494

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

495

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

496

seckeyfilename);

550

497

}

551

498

552

499

ret = gnutls_certificate_set_openpgp_key_file

553

(mc->cred, pubkeyfilename, seckeyfilename,

500

(mc.cred, pubkeyfilename, seckeyfilename,

554

501

GNUTLS_OPENPGP_FMT_BASE64);

555

502

if(ret != GNUTLS_E_SUCCESS){

556

fprintf_plus(stderr,

557

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

558

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

559

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

560

safer_gnutls_strerror(ret));

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));

561

508

goto globalfail;

562

509

}

563

510

564

511

/* GnuTLS server initialization */

565

ret = gnutls_dh_params_init(&mc->dh_params);

512

ret = gnutls_dh_params_init(&mc.dh_params);

566

513

if(ret != GNUTLS_E_SUCCESS){

567

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

568

" initialization: %s\n",

569

safer_gnutls_strerror(ret));

514

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

515

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

570

516

goto globalfail;

571

517

}

572

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

518

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

573

519

if(ret != GNUTLS_E_SUCCESS){

574

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

575

safer_gnutls_strerror(ret));

520

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

521

safer_gnutls_strerror(ret));

576

522

goto globalfail;

577

523

}

578

524

579

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

525

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

580

526

581

527

return 0;

582

528

583

529

globalfail:

584

530

585

gnutls_certificate_free_credentials(mc->cred);

531

gnutls_certificate_free_credentials(mc.cred);

586

532

gnutls_global_deinit();

587

gnutls_dh_params_deinit(mc->dh_params);

533

gnutls_dh_params_deinit(mc.dh_params);

588

534

return -1;

589

535

}

590

536

591

__attribute__((nonnull, warn_unused_result))

592

static int init_gnutls_session(gnutls_session_t *session,

593

mandos_context *mc){

537

static int init_gnutls_session(gnutls_session_t *session){

594

538

int ret;

595

539

/* GnuTLS session creation */

596

540

do {

600

544

}

601

545

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

602

546

if(ret != GNUTLS_E_SUCCESS){

603

fprintf_plus(stderr,

604

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

605

safer_gnutls_strerror(ret));

547

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

548

safer_gnutls_strerror(ret));

606

549

}

607

550

608

551

{

609

552

const char *err;

610

553

do {

611

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

554

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

612

555

if(quit_now){

613

556

gnutls_deinit(*session);

614

557

return -1;

615

558

}

616

559

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

617

560

if(ret != GNUTLS_E_SUCCESS){

618

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

619

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

620

safer_gnutls_strerror(ret));

561

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

562

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

563

safer_gnutls_strerror(ret));

621

564

gnutls_deinit(*session);

622

565

return -1;

623

566

}

625

568

626

569

do {

627

570

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

628

mc->cred);

571

mc.cred);

629

572

if(quit_now){

630

573

gnutls_deinit(*session);

631

574

return -1;

632

575

}

633

576

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

634

577

if(ret != GNUTLS_E_SUCCESS){

635

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

636

safer_gnutls_strerror(ret));

578

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

579

safer_gnutls_strerror(ret));

637

580

gnutls_deinit(*session);

638

581

return -1;

639

582

}

641

584

/* ignore client certificate if any. */

642

585

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

643

586

644

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

587

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

645

588

646

589

return 0;

647

590

}

650

593

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

651

594

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

652

595

653

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

654

__attribute__((warn_unused_result))

655

error_t raise_privileges(void){

656

error_t old_errno = errno;

657

error_t ret_errno = 0;

658

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

659

ret_errno = errno;

660

}

661

errno = old_errno;

662

return ret_errno;

663

}

664

665

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

666

__attribute__((warn_unused_result))

667

error_t raise_privileges_permanently(void){

668

error_t old_errno = errno;

669

error_t ret_errno = raise_privileges();

670

if(ret_errno != 0){

671

errno = old_errno;

672

return ret_errno;

673

}

674

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

675

ret_errno = errno;

676

}

677

errno = old_errno;

678

return ret_errno;

679

}

680

681

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

682

__attribute__((warn_unused_result))

683

error_t lower_privileges(void){

684

error_t old_errno = errno;

685

error_t ret_errno = 0;

686

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

687

ret_errno = errno;

688

}

689

errno = old_errno;

690

return ret_errno;

691

}

692

693

/* Lower privileges permanently */

694

__attribute__((warn_unused_result))

695

error_t lower_privileges_permanently(void){

696

error_t old_errno = errno;

697

error_t ret_errno = 0;

698

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

699

ret_errno = errno;

700

}

701

errno = old_errno;

702

return ret_errno;

703

}

704

705

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

706

__attribute__((nonnull, warn_unused_result))

707

static bool add_remove_local_route(const bool add,

708

const char *address,

709

AvahiIfIndex if_index){

710

int ret;

711

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

712

char add_arg[] = "add";

713

char delete_arg[] = "delete";

714

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

715

if(pluginhelperdir == NULL){

716

if(debug){

717

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

718

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

719

}

720

return false;

721

}

722

723

char interface[IF_NAMESIZE];

724

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

725

perror_plus("if_indextoname");

726

return false;

727

}

728

729

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

730

if(devnull == -1){

731

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

732

return false;

733

}

734

pid_t pid = fork();

735

if(pid == 0){

736

/* Child */

737

/* Raise privileges */

738

errno = raise_privileges_permanently();

739

if(errno != 0){

740

perror_plus("Failed to raise privileges");

741

/* _exit(EX_NOPERM); */

742

} else {

743

/* Set group */

744

errno = 0;

745

ret = setgid(0);

746

if(ret == -1){

747

perror_plus("setgid");

748

_exit(EX_NOPERM);

749

}

750

/* Reset supplementary groups */

751

errno = 0;

752

ret = setgroups(0, NULL);

753

if(ret == -1){

754

perror_plus("setgroups");

755

_exit(EX_NOPERM);

756

}

757

}

758

ret = dup2(devnull, STDIN_FILENO);

759

if(ret == -1){

760

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

761

_exit(EX_OSERR);

762

}

763

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

764

if(ret == -1){

765

perror_plus("close");

766

_exit(EX_OSERR);

767

}

768

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

769

if(ret == -1){

770

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

771

_exit(EX_OSERR);

772

}

773

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

774

O_RDONLY

775

| O_DIRECTORY

776

| O_PATH

777

| O_CLOEXEC));

778

if(helperdir_fd == -1){

779

perror_plus("open");

780

_exit(EX_UNAVAILABLE);

781

}

782

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

783

helper, O_RDONLY));

784

if(helper_fd == -1){

785

perror_plus("openat");

786

_exit(EX_UNAVAILABLE);

787

}

788

TEMP_FAILURE_RETRY(close(helperdir_fd));

789

#ifdef __GNUC__

790

#pragma GCC diagnostic push

791

#pragma GCC diagnostic ignored "-Wcast-qual"

792

#endif

793

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

794

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

795

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

796

#ifdef __GNUC__

797

#pragma GCC diagnostic pop

798

#endif

799

perror_plus("fexecve");

800

_exit(EXIT_FAILURE);

801

}

802

}

803

if(pid == -1){

804

perror_plus("fork");

805

return false;

806

}

807

int status;

808

pid_t pret = -1;

809

errno = 0;

810

do {

811

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

812

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

813

int errno_raising = 0;

814

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

815

errno_raising = errno;

816

perror_plus("Failed to raise privileges in order to"

817

" kill helper program");

818

}

819

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

820

perror_plus("kill");

821

}

822

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

823

perror_plus("Failed to lower privileges after killing"

824

" helper program");

825

}

826

return false;

827

}

828

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

829

if(pret == -1){

830

perror_plus("waitpid");

831

return false;

832

}

833

if(WIFEXITED(status)){

834

if(WEXITSTATUS(status) != 0){

835

fprintf_plus(stderr, "Error: iprouteadddel exited"

836

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

837

return false;

838

}

839

return true;

840

}

841

if(WIFSIGNALED(status)){

842

fprintf_plus(stderr, "Error: iprouteadddel died by"

843

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

844

return false;

845

}

846

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

847

return false;

848

}

849

850

__attribute__((nonnull, warn_unused_result))

851

static bool add_local_route(const char *address,

852

AvahiIfIndex if_index){

853

return add_remove_local_route(true, address, if_index);

854

}

855

856

__attribute__((nonnull, warn_unused_result))

857

static bool remove_local_route(const char *address,

858

AvahiIfIndex if_index){

859

return add_remove_local_route(false, address, if_index);

860

}

861

862

596

/* Called when a Mandos server is found */

863

__attribute__((nonnull, warn_unused_result))

864

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

597

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

865

598

AvahiIfIndex if_index,

866

int af, mandos_context *mc){

599

int af){

867

600

int ret, tcp_sd = -1;

868

601

ssize_t sret;

869

struct sockaddr_storage to;

602

union {

603

struct sockaddr_in in;

604

struct sockaddr_in6 in6;

605

} to;

870

606

char *buffer = NULL;

871

607

char *decrypted_buffer = NULL;

872

608

size_t buffer_length = 0;

875

611

int retval = -1;

876

612

gnutls_session_t session;

877

613

int pf; /* Protocol family */

878

bool route_added = false;

879

614

880

615

errno = 0;

881

616

892

627

pf = PF_INET;

893

628

break;

894

629

default:

895

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

630

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

896

631

errno = EINVAL;

897

632

return -1;

898

633

}

899

634

900

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

901

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

902

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

903

bool match = false;

904

{

905

char *interface = NULL;

906

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

907

interface))){

908

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

909

match = true;

910

break;

911

}

912

}

913

}

914

if(not match){

915

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

916

connect to the server */

917

if(debug){

918

char interface[IF_NAMESIZE];

919

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

920

perror_plus("if_indextoname");

921

} else {

922

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

923

" \"%s\"\n",

924

if_indextoname((unsigned int)if_index,

925

interface));

926

}

927

}

928

return -1;

929

}

930

}

931

932

ret = init_gnutls_session(&session, mc);

635

ret = init_gnutls_session(&session);

933

636

if(ret != 0){

934

637

return -1;

935

638

}

936

639

937

640

if(debug){

938

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

939

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

641

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

642

"\n", ip, port);

940

643

}

941

644

942

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

645

tcp_sd = socket(pf, SOCK_STREAM, 0);

943

646

if(tcp_sd < 0){

944

647

int e = errno;

945

648

perror_plus("socket");

954

657

955

658

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

956

659

if(af == AF_INET6){

957

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

958

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);

959

662

} else { /* IPv4 */

960

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

961

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);

962

665

}

963

666

if(ret < 0 ){

964

667

int e = errno;

968

671

}

969

672

if(ret == 0){

970

673

int e = errno;

971

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

674

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

972

675

errno = e;

973

676

goto mandos_end;

974

677

}

975

678

if(af == AF_INET6){

976

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

977

if(IN6_IS_ADDR_LINKLOCAL

978

(&((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*/

979

686

if(if_index == AVAHI_IF_UNSPEC){

980

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

981

" incomplete without a network interface\n");

687

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

688

" without a network interface\n");

982

689

errno = EINVAL;

983

690

goto mandos_end;

984

691

}

985

692

/* Set the network interface number as scope */

986

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

693

to.in6.sin6_scope_id = (uint32_t)if_index;

987

694

}

988

695

} else {

989

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

696

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

697

-Wconversion and

698

-Wunreachable-code */

990

699

}

991

700

992

701

if(quit_now){

1000

709

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

1001

710

perror_plus("if_indextoname");

1002

711

} else {

1003

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

1004

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

712

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

713

ip, interface, port);

1005

714

}

1006

715

} else {

1007

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

1008

ip, (uintmax_t)port);

716

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

717

port);

1009

718

}

1010

719

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

1011

720

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

1012

if(af == AF_INET6){

1013

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

1014

sizeof(struct sockaddr_in6),

1015

addrstr, sizeof(addrstr), NULL, 0,

1016

NI_NUMERICHOST);

1017

} else {

1018

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

1019

sizeof(struct sockaddr_in),

1020

addrstr, sizeof(addrstr), NULL, 0,

1021

NI_NUMERICHOST);

1022

}

1023

if(ret == EAI_SYSTEM){

1024

perror_plus("getnameinfo");

1025

} else if(ret != 0) {

1026

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

1027

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

1028

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

1029

}

1030

}

1031

1032

if(quit_now){

1033

errno = EINTR;

1034

goto mandos_end;

1035

}

1036

1037

while(true){

1038

if(af == AF_INET6){

1039

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

1040

sizeof(struct sockaddr_in6));

1041

} else {

1042

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

1043

sizeof(struct sockaddr_in));

1044

}

1045

if(ret < 0){

1046

if(errno == ENETUNREACH

1047

and if_index != AVAHI_IF_UNSPEC

1048

and connect_to == NULL

1049

and not route_added and

1050

((af == AF_INET6 and not

1051

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1052

&to)->sin6_addr)))

1053

or (af == AF_INET and

1054

/* Not a a IPv4LL address */

1055

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

1056

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

1057

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

1058

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

1059

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

1060

connect to a Mandos server announced by Avahi on a server

1061

host with a global address. Work around this by retrying

1062

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

1063

1064

Avahi bug reference:

1065

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

1066

https://bugs.debian.org/587961

1067

*/

1068

int e = errno;

1069

route_added = add_local_route(ip, if_index);

1070

if(route_added){

1071

continue;

1072

}

1073

errno = e;

1074

}

1075

if(errno != ECONNREFUSED or debug){

1076

int e = errno;

1077

perror_plus("connect");

1078

errno = e;

1079

}

1080

goto mandos_end;

1081

}

1082

1083

if(quit_now){

1084

errno = EINTR;

1085

goto mandos_end;

1086

}

1087

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;

1088

760

}

1089

761

1090

762

const char *out = mandos_protocol_version;

1092

764

while(true){

1093

765

size_t out_size = strlen(out);

1094

766

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

1095

out_size - written));

767

out_size - written));

1096

768

if(ret == -1){

1097

769

int e = errno;

1098

770

perror_plus("write");

1118

790

}

1119

791

1120

792

if(debug){

1121

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

793

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

1122

794

}

1123

795

1124

796

if(quit_now){

1126

798

goto mandos_end;

1127

799

}

1128

800

1129

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

1130

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

1131

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

1132

gnutls_transport_set_ptr(session,

1133

(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);

1134

803

1135

804

if(quit_now){

1136

805

errno = EINTR;

1147

816

1148

817

if(ret != GNUTLS_E_SUCCESS){

1149

818

if(debug){

1150

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

819

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

1151

820

gnutls_perror(ret);

1152

821

}

1153

822

errno = EPROTO;

1157

826

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

1158

827

1159

828

if(debug){

1160

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

1161

" %s\n", ip);

829

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

830

ip);

1162

831

}

1163

832

1164

833

while(true){

1169

838

}

1170

839

1171

840

buffer_capacity = incbuffer(&buffer, buffer_length,

1172

buffer_capacity);

841

buffer_capacity);

1173

842

if(buffer_capacity == 0){

1174

843

int e = errno;

1175

844

perror_plus("incbuffer");

1202

871

}

1203

872

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

1204

873

if(ret < 0){

1205

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

1206

"***\n");

874

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

1207

875

gnutls_perror(ret);

1208

876

errno = EPROTO;

1209

877

goto mandos_end;

1210

878

}

1211

879

break;

1212

880

default:

1213

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

1214

" encrypted session with Mandos server\n");

881

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

882

" encrypted session with Mandos server\n");

1215

883

gnutls_bye(session, GNUTLS_SHUT_RDWR);

1216

884

errno = EIO;

1217

885

goto mandos_end;

1222

890

}

1223

891

1224

892

if(debug){

1225

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

893

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

1226

894

}

1227

895

1228

896

if(quit_now){

1240

908

1241

909

if(buffer_length > 0){

1242

910

ssize_t decrypted_buffer_size;

1243

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1244

&decrypted_buffer, mc);

911

decrypted_buffer_size = pgp_packet_decrypt(buffer,

912

buffer_length,

913

&decrypted_buffer);

1245

914

if(decrypted_buffer_size >= 0){

1246

915

1247

916

written = 0;

1257

926

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

1258

927

int e = errno;

1259

928

if(debug){

1260

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

1261

strerror(errno));

929

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

930

strerror(errno));

1262

931

}

1263

932

errno = e;

1264

933

goto mandos_end;

1273

942

1274

943

mandos_end:

1275

944

{

1276

if(route_added){

1277

if(not remove_local_route(ip, if_index)){

1278

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

1279

" interface %d", ip, if_index);

1280

}

1281

}

1282

945

int e = errno;

1283

946

free(decrypted_buffer);

1284

947

free(buffer);

1301

964

return retval;

1302

965

}

1303

966

1304

__attribute__((nonnull))

1305

967

static void resolve_callback(AvahiSServiceResolver *r,

1306

968

AvahiIfIndex interface,

1307

969

AvahiProtocol proto,

1315

977

AVAHI_GCC_UNUSED AvahiStringList *txt,

1316

978

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1317

979

flags,

1318

void *mc){

1319

if(r == NULL){

1320

return;

1321

}

980

AVAHI_GCC_UNUSED void* userdata){

981

assert(r);

1322

982

1323

983

/* Called whenever a service has been resolved successfully or

1324

984

timed out */

1325

985

1326

986

if(quit_now){

1327

avahi_s_service_resolver_free(r);

1328

987

return;

1329

988

}

1330

989

1331

990

switch(event){

1332

991

default:

1333

992

case AVAHI_RESOLVER_FAILURE:

1334

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

1335

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

1336

domain,

1337

avahi_strerror(avahi_server_errno

1338

(((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)));

1339

996

break;

1340

997

1341

998

case AVAHI_RESOLVER_FOUND:

1343

1000

char ip[AVAHI_ADDRESS_STR_MAX];

1344

1001

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

1345

1002

if(debug){

1346

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

1347

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

1348

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);

1349

1006

}

1350

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

1351

interface,

1352

avahi_proto_to_af(proto),

1353

mc);

1007

int ret = start_mandos_communication(ip, port, interface,

1008

avahi_proto_to_af(proto));

1354

1009

if(ret == 0){

1355

avahi_simple_poll_quit(simple_poll);

1010

avahi_simple_poll_quit(mc.simple_poll);

1356

1011

} else {

1357

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

1358

avahi_proto_to_af(proto),

1359

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

1360

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

1361

" list\n", name);

1362

}

1012

ret = add_server(ip, port, interface,

1013

avahi_proto_to_af(proto));

1363

1014

}

1364

1015

}

1365

1016

}

1375

1026

const char *domain,

1376

1027

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1377

1028

flags,

1378

void *mc){

1379

if(b == NULL){

1380

return;

1381

}

1029

AVAHI_GCC_UNUSED void* userdata){

1030

assert(b);

1382

1031

1383

1032

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

1384

1033

is removed from the LAN */

1391

1040

default:

1392

1041

case AVAHI_BROWSER_FAILURE:

1393

1042

1394

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

1395

avahi_strerror(avahi_server_errno

1396

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

1397

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);

1398

1046

return;

1399

1047

1400

1048

case AVAHI_BROWSER_NEW:

1403

1051

the callback function is called the Avahi server will free the

1404

1052

resolver for us. */

1405

1053

1406

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

1407

interface, protocol, name, type,

1408

domain, protocol, 0,

1409

resolve_callback, mc) == NULL)

1410

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

1411

" %s\n", name,

1412

avahi_strerror(avahi_server_errno

1413

(((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)));

1414

1059

break;

1415

1060

1416

1061

case AVAHI_BROWSER_REMOVE:

1419

1064

case AVAHI_BROWSER_ALL_FOR_NOW:

1420

1065

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1421

1066

if(debug){

1422

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

1423

" searching...\n");

1067

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

1424

1068

}

1425

1069

break;

1426

1070

}

1435

1079

signal_received = sig;

1436

1080

int old_errno = errno;

1437

1081

/* set main loop to exit */

1438

if(simple_poll != NULL){

1439

avahi_simple_poll_quit(simple_poll);

1082

if(mc.simple_poll != NULL){

1083

avahi_simple_poll_quit(mc.simple_poll);

1440

1084

}

1441

1085

errno = old_errno;

1442

1086

}

1443

1087

1444

__attribute__((nonnull, warn_unused_result))

1445

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

1446

int ret;

1447

error_t ret_errno;

1448

1449

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

1450

if(s < 0){

1451

ret_errno = errno;

1452

perror_plus("socket");

1453

errno = ret_errno;

1454

return false;

1455

}

1456

strcpy(ifr->ifr_name, ifname);

1457

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1458

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){

1459

1144

if(debug){

1460

ret_errno = errno;

1461

perror_plus("ioctl SIOCGIFFLAGS");

1462

errno = ret_errno;

1145

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

1146

flagstring, if_entry->d_name);

1463

1147

}

1464

return false;

1148

free(flagstring);

1149

return 0;

1465

1150

}

1466

return true;

1467

}

1468

1469

__attribute__((nonnull, warn_unused_result))

1470

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

1471

1151

free(flagstring);

1152

ifreq_flags flags = (ifreq_flags)tmpmax;

1472

1153

/* Reject the loopback device */

1473

if(ifr->ifr_flags & IFF_LOOPBACK){

1154

if(flags & IFF_LOOPBACK){

1474

1155

if(debug){

1475

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

1476

ifname);

1156

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

1157

if_entry->d_name);

1477

1158

}

1478

return false;

1159

return 0;

1479

1160

}

1480

1161

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

1481

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

1162

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

1482

1163

if(debug){

1483

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

1484

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

1164

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

1165

if_entry->d_name);

1485

1166

}

1486

return true;

1167

return 1;

1487

1168

}

1488

1169

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

1489

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

1170

if(not (flags & IFF_BROADCAST)){

1490

1171

if(debug){

1491

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1492

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

1172

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

1173

if_entry->d_name);

1493

1174

}

1494

return false;

1175

return 0;

1495

1176

}

1496

1177

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

1497

if(ifr->ifr_flags & IFF_NOARP){

1178

if(flags & IFF_NOARP){

1498

1179

if(debug){

1499

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

1500

ifname);

1180

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

1181

if_entry->d_name);

1501

1182

}

1502

return false;

1183

return 0;

1503

1184

}

1504

1505

1185

/* Accept this device */

1506

1186

if(debug){

1507

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

1508

}

1509

return true;

1510

}

1511

1512

/*

1513

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

1514

* corresponds to an acceptable network device.

1515

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

1516

*/

1517

__attribute__((nonnull, warn_unused_result))

1518

int good_interface(const struct dirent *if_entry){

1519

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

1520

return 0;

1521

}

1522

1523

struct ifreq ifr;

1524

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

1525

if(debug){

1526

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

1527

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

1528

}

1529

return 0;

1530

}

1531

1532

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

1533

return 0;

1187

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

1188

if_entry->d_name);

1534

1189

}

1535

1190

return 1;

1536

1191

}

1537

1192

1538

/*

1539

* This function determines if a network interface is up.

1540

*/

1541

__attribute__((nonnull, warn_unused_result))

1542

bool interface_is_up(const char *interface){

1543

struct ifreq ifr;

1544

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

1545

if(debug){

1546

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

1547

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

1548

}

1549

return false;

1550

}

1551

1552

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

1553

}

1554

1555

/*

1556

* This function determines if a network interface is running

1557

*/

1558

__attribute__((nonnull, warn_unused_result))

1559

bool interface_is_running(const char *interface){

1560

struct ifreq ifr;

1561

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

1562

if(debug){

1563

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

1564

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

1565

}

1566

return false;

1567

}

1568

1569

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

1570

}

1571

1572

__attribute__((nonnull, pure, warn_unused_result))

1573

1193

int notdotentries(const struct dirent *direntry){

1574

1194

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

1575

1195

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

1581

1201

return 1;

1582

1202

}

1583

1203

1584

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

1585

__attribute__((nonnull, warn_unused_result))

1586

int runnable_hook(const struct dirent *direntry){

1587

int ret;

1588

size_t sret;

1589

struct stat st;

1590

1591

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

1592

/* Empty name? */

1593

return 0;

1594

}

1595

1596

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

1597

"abcdefghijklmnopqrstuvwxyz"

1598

"0123456789"

1599

"_.-");

1600

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

1601

/* Contains non-allowed characters */

1602

if(debug){

1603

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

1604

direntry->d_name);

1605

}

1606

return 0;

1607

}

1608

1609

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

1610

if(ret == -1){

1611

if(debug){

1612

perror_plus("Could not stat hook");

1613

}

1614

return 0;

1615

}

1616

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

1617

/* Not a regular file */

1618

if(debug){

1619

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

1620

direntry->d_name);

1621

}

1622

return 0;

1623

}

1624

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

1625

/* Not executable */

1626

if(debug){

1627

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

1628

direntry->d_name);

1629

}

1630

return 0;

1631

}

1632

if(debug){

1633

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

1634

direntry->d_name);

1635

}

1636

return 1;

1637

}

1638

1639

__attribute__((nonnull, warn_unused_result))

1640

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1641

mandos_context *mc){

1204

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1642

1205

int ret;

1643

1206

struct timespec now;

1644

1207

struct timespec waited_time;

1645

1208

intmax_t block_time;

1646

1209

1647

1210

while(true){

1648

if(mc->current_server == NULL){

1649

if(debug){

1650

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

1651

" 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");

1652

1215

}

1653

1216

ret = avahi_simple_poll_iterate(s, -1);

1654

1217

} else {

1655

if(debug){

1656

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

1657

" it, or wait\n");

1218

if (debug){

1219

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

1220

" or wait\n");

1658

1221

}

1659

1222

/* the current time */

1660

1223

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1665

1228

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

1666

1229

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

1667

1230

waited_time.tv_sec = (now.tv_sec

1668

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

1231

- mc.current_server->last_seen.tv_sec);

1669

1232

waited_time.tv_nsec = (now.tv_nsec

1670

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

1233

- mc.current_server->last_seen.tv_nsec);

1671

1234

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

1672

1235

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

1673

1236

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

1675

1238

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

1676

1239

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

1677

1240

1678

if(debug){

1679

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

1680

block_time);

1241

if (debug){

1242

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

1681

1243

}

1682

1244

1683

1245

if(block_time <= 0){

1684

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

1685

mc->current_server->port,

1686

mc->current_server->if_index,

1687

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);

1688

1250

if(ret == 0){

1689

avahi_simple_poll_quit(s);

1251

avahi_simple_poll_quit(mc.simple_poll);

1690

1252

return 0;

1691

1253

}

1692

1254

ret = clock_gettime(CLOCK_MONOTONIC,

1693

&mc->current_server->last_seen);

1255

&mc.current_server->last_seen);

1694

1256

if(ret == -1){

1695

1257

perror_plus("clock_gettime");

1696

1258

return -1;

1697

1259

}

1698

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

1260

mc.current_server = mc.current_server->next;

1699

1261

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

1700

1262

servers, but don't block */

1701

1263

}

1703

1265

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

1704

1266

}

1705

1267

if(ret != 0){

1706

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

1268

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

1707

1269

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

1708

1270

}

1709

1271

}

1710

1272

}

1711

1273

}

1712

1274

1713

__attribute__((nonnull))

1714

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

1715

const float delay){

1716

struct dirent **direntries = NULL;

1717

if(hookdir_fd == -1){

1718

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1719

| O_CLOEXEC);

1720

if(hookdir_fd == -1){

1721

if(errno == ENOENT){

1722

if(debug){

1723

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

1724

" found\n", hookdir);

1725

}

1726

} else {

1727

perror_plus("open");

1728

}

1729

return;

1730

}

1731

}

1732

#ifdef __GLIBC__

1733

#if __GLIBC_PREREQ(2, 15)

1734

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

1735

runnable_hook, alphasort);

1736

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

1737

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

1738

alphasort);

1739

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

1740

#else /* not __GLIBC__ */

1741

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

1742

alphasort);

1743

#endif /* not __GLIBC__ */

1744

if(numhooks == -1){

1745

perror_plus("scandir");

1746

return;

1747

}

1748

struct dirent *direntry;

1749

int ret;

1750

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

1751

if(devnull == -1){

1752

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

1753

return;

1754

}

1755

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

1756

direntry = direntries[i];

1757

if(debug){

1758

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

1759

direntry->d_name);

1760

}

1761

pid_t hook_pid = fork();

1762

if(hook_pid == 0){

1763

/* Child */

1764

/* Raise privileges */

1765

errno = raise_privileges_permanently();

1766

if(errno != 0){

1767

perror_plus("Failed to raise privileges");

1768

_exit(EX_NOPERM);

1769

}

1770

/* Set group */

1771

errno = 0;

1772

ret = setgid(0);

1773

if(ret == -1){

1774

perror_plus("setgid");

1775

_exit(EX_NOPERM);

1776

}

1777

/* Reset supplementary groups */

1778

errno = 0;

1779

ret = setgroups(0, NULL);

1780

if(ret == -1){

1781

perror_plus("setgroups");

1782

_exit(EX_NOPERM);

1783

}

1784

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

1785

if(ret == -1){

1786

perror_plus("setenv");

1787

_exit(EX_OSERR);

1788

}

1789

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

1790

if(ret == -1){

1791

perror_plus("setenv");

1792

_exit(EX_OSERR);

1793

}

1794

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

1795

if(ret == -1){

1796

perror_plus("setenv");

1797

_exit(EX_OSERR);

1798

}

1799

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

1800

if(ret == -1){

1801

perror_plus("setenv");

1802

_exit(EX_OSERR);

1803

}

1804

char *delaystring;

1805

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

1806

if(ret == -1){

1807

perror_plus("asprintf");

1808

_exit(EX_OSERR);

1809

}

1810

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

1811

if(ret == -1){

1812

free(delaystring);

1813

perror_plus("setenv");

1814

_exit(EX_OSERR);

1815

}

1816

free(delaystring);

1817

if(connect_to != NULL){

1818

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

1819

if(ret == -1){

1820

perror_plus("setenv");

1821

_exit(EX_OSERR);

1822

}

1823

}

1824

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

1825

direntry->d_name,

1826

O_RDONLY));

1827

if(hook_fd == -1){

1828

perror_plus("openat");

1829

_exit(EXIT_FAILURE);

1830

}

1831

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

1832

perror_plus("close");

1833

_exit(EXIT_FAILURE);

1834

}

1835

ret = dup2(devnull, STDIN_FILENO);

1836

if(ret == -1){

1837

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

1838

_exit(EX_OSERR);

1839

}

1840

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

1841

if(ret == -1){

1842

perror_plus("close");

1843

_exit(EX_OSERR);

1844

}

1845

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1846

if(ret == -1){

1847

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

1848

_exit(EX_OSERR);

1849

}

1850

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

1851

environ) == -1){

1852

perror_plus("fexecve");

1853

_exit(EXIT_FAILURE);

1854

}

1855

} else {

1856

if(hook_pid == -1){

1857

perror_plus("fork");

1858

free(direntry);

1859

continue;

1860

}

1861

int status;

1862

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

1863

perror_plus("waitpid");

1864

free(direntry);

1865

continue;

1866

}

1867

if(WIFEXITED(status)){

1868

if(WEXITSTATUS(status) != 0){

1869

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

1870

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

1871

WEXITSTATUS(status));

1872

free(direntry);

1873

continue;

1874

}

1875

} else if(WIFSIGNALED(status)){

1876

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

1877

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

1878

WTERMSIG(status));

1879

free(direntry);

1880

continue;

1881

} else {

1882

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

1883

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

1884

free(direntry);

1885

continue;

1886

}

1887

}

1888

if(debug){

1889

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

1890

direntry->d_name);

1891

}

1892

free(direntry);

1893

}

1894

free(direntries);

1895

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

1896

perror_plus("close");

1897

} else {

1898

hookdir_fd = -1;

1899

}

1900

close(devnull);

1901

}

1902

1903

__attribute__((nonnull, warn_unused_result))

1904

error_t bring_up_interface(const char *const interface,

1905

const float delay){

1906

error_t old_errno = errno;

1907

int ret;

1908

struct ifreq network;

1909

unsigned int if_index = if_nametoindex(interface);

1910

if(if_index == 0){

1911

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

1912

errno = old_errno;

1913

return ENXIO;

1914

}

1915

1916

if(quit_now){

1917

errno = old_errno;

1918

return EINTR;

1919

}

1920

1921

if(not interface_is_up(interface)){

1922

error_t ret_errno = 0, ioctl_errno = 0;

1923

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

1924

ret_errno = errno;

1925

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

1926

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

1927

errno = old_errno;

1928

return ret_errno;

1929

}

1930

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

1931

1932

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

1933

if(sd == -1){

1934

ret_errno = errno;

1935

perror_plus("socket");

1936

errno = old_errno;

1937

return ret_errno;

1938

}

1939

1940

if(quit_now){

1941

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

1942

if(ret == -1){

1943

perror_plus("close");

1944

}

1945

errno = old_errno;

1946

return EINTR;

1947

}

1948

1949

if(debug){

1950

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

1951

interface);

1952

}

1953

1954

/* Raise privileges */

1955

ret_errno = raise_privileges();

1956

if(ret_errno != 0){

1957

errno = ret_errno;

1958

perror_plus("Failed to raise privileges");

1959

}

1960

1961

#ifdef __linux__

1962

int ret_linux;

1963

bool restore_loglevel = false;

1964

if(ret_errno == 0){

1965

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1966

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

1967

ret_linux = klogctl(8, NULL, 5);

1968

if(ret_linux == -1){

1969

perror_plus("klogctl");

1970

} else {

1971

restore_loglevel = true;

1972

}

1973

}

1974

#endif /* __linux__ */

1975

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

1976

ioctl_errno = errno;

1977

#ifdef __linux__

1978

if(restore_loglevel){

1979

ret_linux = klogctl(7, NULL, 0);

1980

if(ret_linux == -1){

1981

perror_plus("klogctl");

1982

}

1983

}

1984

#endif /* __linux__ */

1985

1986

/* If raise_privileges() succeeded above */

1987

if(ret_errno == 0){

1988

/* Lower privileges */

1989

ret_errno = lower_privileges();

1990

if(ret_errno != 0){

1991

errno = ret_errno;

1992

perror_plus("Failed to lower privileges");

1993

}

1994

}

1995

1996

/* Close the socket */

1997

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

1998

if(ret == -1){

1999

perror_plus("close");

2000

}

2001

2002

if(ret_setflags == -1){

2003

errno = ioctl_errno;

2004

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2005

errno = old_errno;

2006

return ioctl_errno;

2007

}

2008

} else if(debug){

2009

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

2010

interface);

2011

}

2012

2013

/* Sleep checking until interface is running.

2014

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

2015

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

2016

if(interface_is_running(interface)){

2017

break;

2018

}

2019

struct timespec sleeptime = { .tv_nsec = 250000000 };

2020

ret = nanosleep(&sleeptime, NULL);

2021

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

2022

perror_plus("nanosleep");

2023

}

2024

}

2025

2026

errno = old_errno;

2027

return 0;

2028

}

2029

2030

__attribute__((nonnull, warn_unused_result))

2031

error_t take_down_interface(const char *const interface){

2032

error_t old_errno = errno;

2033

struct ifreq network;

2034

unsigned int if_index = if_nametoindex(interface);

2035

if(if_index == 0){

2036

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

2037

errno = old_errno;

2038

return ENXIO;

2039

}

2040

if(interface_is_up(interface)){

2041

error_t ret_errno = 0, ioctl_errno = 0;

2042

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

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 &= ~(short)IFF_UP; /* clear 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(debug){

2060

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

2061

interface);

2062

}

2063

2064

/* Raise privileges */

2065

ret_errno = raise_privileges();

2066

if(ret_errno != 0){

2067

errno = ret_errno;

2068

perror_plus("Failed to raise privileges");

2069

}

2070

2071

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

2072

ioctl_errno = errno;

2073

2074

/* If raise_privileges() succeeded above */

2075

if(ret_errno == 0){

2076

/* Lower privileges */

2077

ret_errno = lower_privileges();

2078

if(ret_errno != 0){

2079

errno = ret_errno;

2080

perror_plus("Failed to lower privileges");

2081

}

2082

}

2083

2084

/* Close the socket */

2085

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

2086

if(ret == -1){

2087

perror_plus("close");

2088

}

2089

2090

if(ret_setflags == -1){

2091

errno = ioctl_errno;

2092

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2093

errno = old_errno;

2094

return ioctl_errno;

2095

}

2096

} else if(debug){

2097

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

2098

interface);

2099

}

2100

2101

errno = old_errno;

2102

return 0;

2103

}

2104

2105

1275

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

2106

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

2107

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

2108

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

2109

.interfaces = NULL, .interfaces_size = 0 };

2110

1276

AvahiSServiceBrowser *sb = NULL;

2111

error_t ret_errno;

1277

int error;

2112

1278

int ret;

2113

1279

intmax_t tmpmax;

2114

1280

char *tmp;

2115

1281

int exitcode = EXIT_SUCCESS;

2116

char *interfaces_to_take_down = NULL;

2117

size_t interfaces_to_take_down_size = 0;

2118

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

2119

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

2120

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;

2121

1290

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2122

1291

const char *seckey = PATHDIR "/" SECKEY;

2123

1292

const char *pubkey = PATHDIR "/" PUBKEY;

2124

char *interfaces_hooks = NULL;

2125

1293

2126

1294

bool gnutls_initialized = false;

2127

1295

bool gpgme_initialized = false;

2189

1357

.group = 2 },

2190

1358

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

2191

1359

.arg = "SECONDS",

2192

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

2193

.group = 2 },

2194

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

2195

.arg = "DIR",

2196

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

1360

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

2197

1361

.group = 2 },

2198

1362

/*

2199

1363

* These reproduce what we would get without ARGP_NO_HELP

2218

1382

connect_to = arg;

2219

1383

break;

2220

1384

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

2221

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

2222

arg, (int)',');

2223

if(ret_errno != 0){

2224

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

2225

}

1385

interface = arg;

2226

1386

break;

2227

1387

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

2228

1388

seckey = arg;

2257

1417

argp_error(state, "Bad retry interval");

2258

1418

}

2259

1419

break;

2260

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

2261

hookdir = arg;

2262

break;

2263

1420

/*

2264

1421

* These reproduce what we would get without ARGP_NO_HELP

2265

1422

*/

2271

1428

argp_state_help(state, state->out_stream,

2272

1429

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2273

1430

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

2274

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

1431

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

2275

1432

exit(argp_err_exit_status);

2276

1433

break;

2277

1434

default:

2300

1457

goto end;

2301

1458

}

2302

1459

}

2303

1460

2304

1461

{

2305

1462

/* Work around Debian bug #633582:

2306

1463

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

2307

2308

/* Re-raise privileges */

2309

ret_errno = raise_privileges();

2310

if(ret_errno != 0){

2311

errno = ret_errno;

2312

perror_plus("Failed to raise privileges");

2313

} else {

2314

struct stat st;

2315

2316

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

2317

int seckey_fd = open(seckey, O_RDONLY);

2318

if(seckey_fd == -1){

2319

perror_plus("open");

2320

} else {

2321

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

2322

if(ret == -1){

2323

perror_plus("fstat");

2324

} else {

2325

if(S_ISREG(st.st_mode)

2326

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

2327

ret = fchown(seckey_fd, uid, gid);

2328

if(ret == -1){

2329

perror_plus("fchown");

2330

}

2331

}

2332

}

2333

TEMP_FAILURE_RETRY(close(seckey_fd));

2334

}

2335

}

2336

2337

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

2338

int pubkey_fd = open(pubkey, O_RDONLY);

2339

if(pubkey_fd == -1){

2340

perror_plus("open");

2341

} else {

2342

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

2343

if(ret == -1){

2344

perror_plus("fstat");

2345

} else {

2346

if(S_ISREG(st.st_mode)

2347

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

2348

ret = fchown(pubkey_fd, uid, gid);

2349

if(ret == -1){

2350

perror_plus("fchown");

2351

}

2352

}

2353

}

2354

TEMP_FAILURE_RETRY(close(pubkey_fd));

2355

}

2356

}

2357

2358

/* Lower privileges */

2359

ret_errno = lower_privileges();

2360

if(ret_errno != 0){

2361

errno = ret_errno;

2362

perror_plus("Failed to lower privileges");

2363

}

2364

}

2365

}

2366

2367

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

2368

{

2369

char *interface = NULL;

2370

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

2371

interface))){

2372

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

2373

and if_nametoindex(interface) == 0){

2374

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

2375

fprintf_plus(stderr, "Not using nonexisting interface"

2376

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

2377

}

2378

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

2379

interface = NULL;

2380

}

2381

}

2382

}

2383

2384

/* Run network hooks */

2385

{

2386

if(mc.interfaces != NULL){

2387

interfaces_hooks = malloc(mc.interfaces_size);

2388

if(interfaces_hooks == NULL){

2389

perror_plus("malloc");

2390

goto end;

2391

}

2392

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

2393

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

2394

}

2395

run_network_hooks("start", interfaces_hooks != NULL ?

2396

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

}

2397

1519

}

2398

1520

2399

1521

if(not debug){

2400

1522

avahi_set_log_function(empty_log);

2401

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

}

2402

1549

2403

1550

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

2404

1551

from the signal handler */

2405

1552

/* Initialize the pseudo-RNG for Avahi */

2406

1553

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

2407

simple_poll = avahi_simple_poll_new();

2408

if(simple_poll == NULL){

2409

fprintf_plus(stderr,

2410

"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");

2411

1557

exitcode = EX_UNAVAILABLE;

2412

1558

goto end;

2413

1559

}

2475

1621

}

2476

1622

}

2477

1623

2478

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

2479

if(mc.interfaces == NULL){

2480

struct dirent **direntries = NULL;

2481

/* Look for any good interfaces */

2482

ret = scandir(sys_class_net, &direntries, good_interface,

2483

alphasort);

2484

if(ret >= 1){

2485

/* Add all found interfaces to interfaces list */

2486

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

2487

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

2488

direntries[i]->d_name);

2489

if(ret_errno != 0){

2490

errno = ret_errno;

2491

perror_plus("argz_add");

2492

free(direntries[i]);

2493

continue;

2494

}

2495

if(debug){

2496

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

2497

direntries[i]->d_name);

2498

}

2499

free(direntries[i]);

2500

}

2501

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

}

2502

1760

} else {

2503

if(ret == 0){

2504

free(direntries);

2505

}

2506

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

2507

exitcode = EXIT_FAILURE;

2508

goto end;

2509

}

2510

}

2511

2512

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

2513

{

2514

char *interface = NULL;

2515

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

2516

interface))){

2517

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

2518

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

2519

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

2520

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

2521

interface);

2522

interface = NULL;

2523

while((interface = argz_next(mc.interfaces,

2524

mc.interfaces_size, interface))){

2525

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

2526

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

2527

interface);

2528

interface = NULL;

2529

}

2530

}

2531

break;

2532

}

2533

bool interface_was_up = interface_is_up(interface);

2534

errno = bring_up_interface(interface, delay);

2535

if(not interface_was_up){

2536

if(errno != 0){

2537

perror_plus("Failed to bring up interface");

2538

} else {

2539

errno = argz_add(&interfaces_to_take_down,

2540

&interfaces_to_take_down_size,

2541

interface);

2542

if(errno != 0){

2543

perror_plus("argz_add");

2544

}

2545

}

2546

}

2547

}

2548

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

2549

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

2550

}

2551

}

2552

2553

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

2554

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

2555

if(debug){

2556

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

2557

mc.interfaces);

2558

}

2559

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

}

2560

1767

}

2561

1768

2562

1769

if(quit_now){

2563

1770

goto end;

2564

1771

}

2565

1772

2566

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

1773

ret = init_gnutls_global(pubkey, seckey);

2567

1774

if(ret == -1){

2568

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

1775

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

2569

1776

exitcode = EX_UNAVAILABLE;

2570

1777

goto end;

2571

1778

} else {

2576

1783

goto end;

2577

1784

}

2578

1785

2579

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

2580

tempdir = mkdtemp(run_tempdir);

2581

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

2582

if(debug){

2583

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

2584

run_tempdir, old_tempdir);

2585

}

2586

tempdir = mkdtemp(old_tempdir);

2587

}

2588

if(tempdir == NULL){

1786

if(mkdtemp(tempdir) == NULL){

2589

1787

perror_plus("mkdtemp");

2590

1788

goto end;

2591

1789

}

1790

tempdir_created = true;

2592

1791

2593

1792

if(quit_now){

2594

1793

goto end;

2595

1794

}

2596

1795

2597

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

2598

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

1796

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

1797

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

2599

1798

exitcode = EX_UNAVAILABLE;

2600

1799

goto end;

2601

1800

} else {

2610

1809

/* Connect directly, do not use Zeroconf */

2611

1810

/* (Mainly meant for debugging) */

2612

1811

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

2613

2614

1812

if(address == NULL){

2615

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

1813

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

2616

1814

exitcode = EX_USAGE;

2617

1815

goto end;

2618

1816

}

2621

1819

goto end;

2622

1820

}

2623

1821

2624

in_port_t port;

1822

uint16_t port;

2625

1823

errno = 0;

2626

1824

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

2627

1825

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

2628

or tmpmax != (in_port_t)tmpmax){

2629

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

1826

or tmpmax != (uint16_t)tmpmax){

1827

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

2630

1828

exitcode = EX_USAGE;

2631

1829

goto end;

2632

1830

}

2633

1831

2634

1832

if(quit_now){

2635

1833

goto end;

2636

1834

}

2637

1835

2638

port = (in_port_t)tmpmax;

1836

port = (uint16_t)tmpmax;

2639

1837

*address = '\0';

2640

1838

/* Colon in address indicates IPv6 */

2641

1839

int af;

2657

1855

}

2658

1856

2659

1857

while(not quit_now){

2660

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

2661

&mc);

1858

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

2662

1859

if(quit_now or ret == 0){

2663

1860

break;

2664

1861

}

2665

1862

if(debug){

2666

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

2667

(int)retry_interval);

1863

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

1864

(int)retry_interval);

2668

1865

}

2669

sleep((unsigned int)retry_interval);

1866

sleep((int)retry_interval);

2670

1867

}

2671

1868

2672

if(not quit_now){

1869

if (not quit_now){

2673

1870

exitcode = EXIT_SUCCESS;

2674

1871

}

2675

1872

2676

1873

goto end;

2677

1874

}

2678

1875

2690

1887

config.publish_domain = 0;

2691

1888

2692

1889

/* Allocate a new server */

2693

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2694

&config, NULL, NULL, &ret_errno);

1890

mc.server = avahi_server_new(avahi_simple_poll_get

1891

(mc.simple_poll), &config, NULL,

1892

NULL, &error);

2695

1893

2696

1894

/* Free the Avahi configuration data */

2697

1895

avahi_server_config_free(&config);

2699

1897

2700

1898

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

2701

1899

if(mc.server == NULL){

2702

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

2703

avahi_strerror(ret_errno));

1900

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

1901

avahi_strerror(error));

2704

1902

exitcode = EX_UNAVAILABLE;

2705

1903

goto end;

2706

1904

}

2712

1910

/* Create the Avahi service browser */

2713

1911

sb = avahi_s_service_browser_new(mc.server, if_index,

2714

1912

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2715

NULL, 0, browse_callback,

2716

(void *)&mc);

1913

NULL, 0, browse_callback, NULL);

2717

1914

if(sb == NULL){

2718

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

2719

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)));

2720

1917

exitcode = EX_UNAVAILABLE;

2721

1918

goto end;

2722

1919

}

2728

1925

/* Run the main loop */

2729

1926

2730

1927

if(debug){

2731

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

1928

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

2732

1929

}

2733

2734

ret = avahi_loop_with_timeout(simple_poll,

2735

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

1930

1931

ret = avahi_loop_with_timeout(mc.simple_poll,

1932

(int)(retry_interval * 1000));

2736

1933

if(debug){

2737

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

2738

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

1934

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

1935

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

2739

1936

}

2740

1937

2741

1938

end:

2742

1939

2743

1940

if(debug){

2744

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

1941

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

2745

1942

}

2746

1943

2747

1944

/* Cleanup things */

2748

free(mc.interfaces);

2749

2750

1945

if(sb != NULL)

2751

1946

avahi_s_service_browser_free(sb);

2752

1947

2753

1948

if(mc.server != NULL)

2754

1949

avahi_server_free(mc.server);

2755

1950

2756

if(simple_poll != NULL)

2757

avahi_simple_poll_free(simple_poll);

1951

if(mc.simple_poll != NULL)

1952

avahi_simple_poll_free(mc.simple_poll);

2758

1953

2759

1954

if(gnutls_initialized){

2760

1955

gnutls_certificate_free_credentials(mc.cred);

2765

1960

if(gpgme_initialized){

2766

1961

gpgme_release(mc.ctx);

2767

1962

}

2768

1963

2769

1964

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

2770

1965

has seen */

2771

1966

if(mc.current_server != NULL){

2772

1967

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

2773

1968

while(mc.current_server != NULL){

2774

1969

server *next = mc.current_server->next;

2775

#ifdef __GNUC__

2776

#pragma GCC diagnostic push

2777

#pragma GCC diagnostic ignored "-Wcast-qual"

2778

#endif

2779

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

2780

#ifdef __GNUC__

2781

#pragma GCC diagnostic pop

2782

#endif

2783

1970

free(mc.current_server);

2784

1971

mc.current_server = next;

2785

1972

}

2786

1973

}

2787

1974

2788

/* Re-raise privileges */

2789

{

2790

ret_errno = raise_privileges();

2791

if(ret_errno != 0){

2792

errno = ret_errno;

2793

perror_plus("Failed to raise privileges");

2794

} else {

2795

2796

/* Run network hooks */

2797

run_network_hooks("stop", interfaces_hooks != NULL ?

2798

interfaces_hooks : "", delay);

2799

2800

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

2801

{

2802

char *interface = NULL;

2803

while((interface=argz_next(interfaces_to_take_down,

2804

interfaces_to_take_down_size,

2805

interface))){

2806

ret_errno = take_down_interface(interface);

2807

if(ret_errno != 0){

2808

errno = ret_errno;

2809

perror_plus("Failed to take down interface");

2810

}

2811

}

2812

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

2813

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

2814

" down\n");

2815

}

2816

}

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");

2817

1982

}

2818

2819

ret_errno = lower_privileges_permanently();

2820

if(ret_errno != 0){

2821

errno = ret_errno;

2822

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

}

2823

2004

}

2824

2005

}

2825

2006

2826

free(interfaces_to_take_down);

2827

free(interfaces_hooks);

2828

2829

2007

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

2830

if(tempdir != NULL){

2008

if(tempdir_created){

2831

2009

struct dirent **direntries = NULL;

2832

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

2833

| O_NOFOLLOW

2834

| O_DIRECTORY

2835

| O_PATH));

2836

if(tempdir_fd == -1){

2837

perror_plus("open");

2838

} else {

2839

#ifdef __GLIBC__

2840

#if __GLIBC_PREREQ(2, 15)

2841

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

2842

notdotentries, alphasort);

2843

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

2844

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

2845

alphasort);

2846

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

2847

#else /* not __GLIBC__ */

2848

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

2849

alphasort);

2850

#endif /* not __GLIBC__ */

2851

if(numentries >= 0){

2852

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

2853

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

2854

if(ret == -1){

2855

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

2856

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

2857

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

2858

}

2859

free(direntries[i]);

2860

}

2861

2862

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

2863

free(direntries);

2864

if(numentries == -1){

2865

perror_plus("scandir");

2866

}

2867

ret = rmdir(tempdir);

2868

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

2869

perror_plus("rmdir");

2870

}

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);

2871

2029

}

2872

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");

2873

2040

}

2874

2041

}

2875

2042