/mandos/trunk : revision 690

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

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stdout, ferror(), remove() */

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

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

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

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

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strtof(), abort() */

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opendir(), DIR */

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

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

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inet_pton(), connect() */

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inet_pton(), connect(),

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getnameinfo() */

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

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

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

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

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

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

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

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argp_state, struct argp,

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#include <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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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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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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uint16_t port;

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in_port_t port;

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AvahiIfIndex if_index;

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int af;

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struct timespec last_seen;

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/* 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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164

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 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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/* global so signal handler can reach it*/

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AvahiSimplePoll *simple_poll;

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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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program_invocation_short_name);

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errno = e;

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perror(print_text);

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}

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

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

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va_list ap;

180

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va_start (ap, format);

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190

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

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192

program_invocation_short_name));

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

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

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}

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/*

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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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*/

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__attribute__((nonnull, warn_unused_result))

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size_t incbuffer(char **buffer, size_t buffer_length,

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size_t buffer_capacity){

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if(buffer_length + BUFFER_SIZE > buffer_capacity){

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

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if(buffer == NULL){

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

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if(new_buf == NULL){

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int old_errno = errno;

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free(*buffer);

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errno = old_errno;

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*buffer = NULL;

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return 0;

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}

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*buffer = new_buf;

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buffer_capacity += BUFFER_SIZE;

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}

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

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int af){

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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 ret;

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

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if(new_server == NULL){

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perror_plus("malloc");

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return -1;

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return false;

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}

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

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.port = port,

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.af = af };

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if(new_server->ip == NULL){

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perror_plus("strdup");

219

return -1;

235

return false;

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}

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

238

if(ret == -1){

239

perror_plus("clock_gettime");

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return false;

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}

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/* Special case of first server */

222

if (mc.current_server == NULL){

243

if(*current_server == NULL){

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new_server->next = new_server;

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new_server->prev = new_server;

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mc.current_server = new_server;

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

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*current_server = new_server;

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} else {

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new_server->next = mc.current_server;

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

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/* 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->prev->next = new_server;

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mc.current_server->prev = new_server;

232

}

233

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

234

if(ret == -1){

235

perror_plus("clock_gettime");

236

return -1;

237

}

238

return 0;

252

(*current_server)->prev = new_server;

253

}

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return true;

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255

}

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/*

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* Initialize GPGME.

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*/

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

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const char *tempdir){

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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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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.

252

270

*/

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bool import_key(const char *filename){

271

bool import_key(const char * const filename){

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int ret;

255

273

int fd;

256

274

gpgme_data_t pgp_data;

268

286

return false;

269

287

}

270

288

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rc = gpgme_op_import(mc.ctx, pgp_data);

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

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if(rc != GPG_ERR_NO_ERROR){

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291

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

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gpgme_strsource(rc), gpgme_strerror(rc));

318

336

}

319

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320

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/* Create new GPGME "context" */

321

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

339

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

322

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if(rc != GPG_ERR_NO_ERROR){

323

341

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

324

342

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

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355

* Decrypt OpenPGP data.

338

356

* Returns -1 on error

339

357

*/

358

__attribute__((nonnull, warn_unused_result))

340

359

static ssize_t pgp_packet_decrypt(const char *cryptotext,

341

360

size_t crypto_size,

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char **plaintext){

361

char **plaintext,

362

mandos_context *mc){

343

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gpgme_data_t dh_crypto, dh_plain;

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gpgme_error_t rc;

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ssize_t ret;

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

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data buffer */

374

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

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

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if(rc != GPG_ERR_NO_ERROR){

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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plaintext_length = -1;

379

399

if(debug){

380

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gpgme_decrypt_result_t result;

381

result = gpgme_op_decrypt_result(mc.ctx);

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result = gpgme_op_decrypt_result(mc->ctx);

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if(result == NULL){

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403

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

384

404

} else {

461

481

return plaintext_length;

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}

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483

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static const char * safer_gnutls_strerror(int value){

465

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

466

-Wunreachable-code */

484

__attribute__((warn_unused_result))

485

static const char *safer_gnutls_strerror(int value){

486

const char *ret = gnutls_strerror(value);

467

487

if(ret == NULL)

468

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ret = "(unknown)";

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return ret;

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490

}

471

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/* GnuTLS log function callback */

493

__attribute__((nonnull))

473

494

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

474

495

const char* string){

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

476

497

}

477

498

499

__attribute__((nonnull, warn_unused_result))

478

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static int init_gnutls_global(const char *pubkeyfilename,

479

const char *seckeyfilename){

501

const char *seckeyfilename,

502

mandos_context *mc){

480

503

int ret;

481

504

482

505

if(debug){

499

522

}

500

523

501

524

/* OpenPGP credentials */

502

ret = gnutls_certificate_allocate_credentials(&mc.cred);

525

ret = gnutls_certificate_allocate_credentials(&mc->cred);

503

526

if(ret != GNUTLS_E_SUCCESS){

504

527

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

505

528

safer_gnutls_strerror(ret));

515

538

}

516

539

517

540

ret = gnutls_certificate_set_openpgp_key_file

518

(mc.cred, pubkeyfilename, seckeyfilename,

541

(mc->cred, pubkeyfilename, seckeyfilename,

519

542

GNUTLS_OPENPGP_FMT_BASE64);

520

543

if(ret != GNUTLS_E_SUCCESS){

521

544

fprintf_plus(stderr,

527

550

}

528

551

529

552

/* GnuTLS server initialization */

530

ret = gnutls_dh_params_init(&mc.dh_params);

553

ret = gnutls_dh_params_init(&mc->dh_params);

531

554

if(ret != GNUTLS_E_SUCCESS){

532

555

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

533

556

" initialization: %s\n",

534

557

safer_gnutls_strerror(ret));

535

558

goto globalfail;

536

559

}

537

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

560

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

538

561

if(ret != GNUTLS_E_SUCCESS){

539

562

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

540

563

safer_gnutls_strerror(ret));

541

564

goto globalfail;

542

565

}

543

566

544

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

567

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

545

568

546

569

return 0;

547

570

548

571

globalfail:

549

572

550

gnutls_certificate_free_credentials(mc.cred);

573

gnutls_certificate_free_credentials(mc->cred);

551

574

gnutls_global_deinit();

552

gnutls_dh_params_deinit(mc.dh_params);

575

gnutls_dh_params_deinit(mc->dh_params);

553

576

return -1;

554

577

}

555

578

556

static int init_gnutls_session(gnutls_session_t *session){

579

__attribute__((nonnull, warn_unused_result))

580

static int init_gnutls_session(gnutls_session_t *session,

581

mandos_context *mc){

557

582

int ret;

558

583

/* GnuTLS session creation */

559

584

do {

571

596

{

572

597

const char *err;

573

598

do {

574

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

599

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

575

600

if(quit_now){

576

601

gnutls_deinit(*session);

577

602

return -1;

588

613

589

614

do {

590

615

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

591

mc.cred);

616

mc->cred);

592

617

if(quit_now){

593

618

gnutls_deinit(*session);

594

619

return -1;

604

629

/* ignore client certificate if any. */

605

630

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

606

631

607

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

632

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

608

633

609

634

return 0;

610

635

}

614

639

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

615

640

616

641

/* Called when a Mandos server is found */

617

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

642

__attribute__((nonnull, warn_unused_result))

643

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

618

644

AvahiIfIndex if_index,

619

int af){

645

int af, mandos_context *mc){

620

646

int ret, tcp_sd = -1;

621

647

ssize_t sret;

622

union {

623

struct sockaddr_in in;

624

struct sockaddr_in6 in6;

625

} to;

648

struct sockaddr_storage to;

626

649

char *buffer = NULL;

627

650

char *decrypted_buffer = NULL;

628

651

size_t buffer_length = 0;

652

675

return -1;

653

676

}

654

677

655

ret = init_gnutls_session(&session);

678

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

679

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

680

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

681

bool match = false;

682

{

683

char *interface = NULL;

684

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

685

interface))){

686

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

687

match = true;

688

break;

689

}

690

}

691

}

692

if(not match){

693

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

694

connect to the server */

695

if(debug){

696

char interface[IF_NAMESIZE];

697

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

698

perror_plus("if_indextoname");

699

} else {

700

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

701

" \"%s\"\n",

702

if_indextoname((unsigned int)if_index,

703

interface));

704

}

705

}

706

return -1;

707

}

708

}

709

710

ret = init_gnutls_session(&session, mc);

656

711

if(ret != 0){

657

712

return -1;

658

713

}

659

714

660

715

if(debug){

661

716

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

662

PRIu16 "\n", ip, port);

717

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

663

718

}

664

719

665

720

tcp_sd = socket(pf, SOCK_STREAM, 0);

677

732

678

733

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

679

734

if(af == AF_INET6){

680

to.in6.sin6_family = (sa_family_t)af;

681

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

735

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

736

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

682

737

} else { /* IPv4 */

683

to.in.sin_family = (sa_family_t)af;

684

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

738

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

739

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

685

740

}

686

741

if(ret < 0 ){

687

742

int e = errno;

696

751

goto mandos_end;

697

752

}

698

753

if(af == AF_INET6){

699

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

700

-Wconversion and

701

-Wunreachable-code */

702

703

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

704

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

705

-Wunreachable-code*/

754

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

755

if(IN6_IS_ADDR_LINKLOCAL

756

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

706

757

if(if_index == AVAHI_IF_UNSPEC){

707

758

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

708

759

" incomplete without a network interface\n");

710

761

goto mandos_end;

711

762

}

712

763

/* Set the network interface number as scope */

713

to.in6.sin6_scope_id = (uint32_t)if_index;

764

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

714

765

}

715

766

} else {

716

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

717

-Wconversion and

718

-Wunreachable-code */

767

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

719

768

}

720

769

721

770

if(quit_now){

729

778

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

730

779

perror_plus("if_indextoname");

731

780

} else {

732

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

733

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

781

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

782

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

734

783

}

735

784

} else {

736

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

737

ip, port);

785

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

786

ip, (uintmax_t)port);

738

787

}

739

788

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

740

789

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

741

const char *pcret;

742

790

if(af == AF_INET6){

743

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

744

sizeof(addrstr));

791

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

792

sizeof(struct sockaddr_in6),

793

addrstr, sizeof(addrstr), NULL, 0,

794

NI_NUMERICHOST);

745

795

} else {

746

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

747

sizeof(addrstr));

796

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

797

sizeof(struct sockaddr_in),

798

addrstr, sizeof(addrstr), NULL, 0,

799

NI_NUMERICHOST);

748

800

}

749

if(pcret == NULL){

750

perror_plus("inet_ntop");

751

} else {

752

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

753

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

754

}

801

if(ret == EAI_SYSTEM){

802

perror_plus("getnameinfo");

803

} else if(ret != 0) {

804

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

805

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

806

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

755

807

}

756

808

}

757

809

761

813

}

762

814

763

815

if(af == AF_INET6){

764

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

816

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

817

sizeof(struct sockaddr_in6));

765

818

} else {

766

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

819

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

820

sizeof(struct sockaddr_in));

767

821

}

768

822

if(ret < 0){

769

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

823

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

770

824

int e = errno;

771

825

perror_plus("connect");

772

826

errno = e;

818

872

goto mandos_end;

819

873

}

820

874

821

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

822

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

875

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

876

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

877

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

878

gnutls_transport_set_ptr(session,

879

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

823

880

824

881

if(quit_now){

825

882

errno = EINTR;

930

987

if(buffer_length > 0){

931

988

ssize_t decrypted_buffer_size;

932

989

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

933

&decrypted_buffer);

990

&decrypted_buffer, mc);

934

991

if(decrypted_buffer_size >= 0){

935

992

936

993

written = 0;

984

1041

return retval;

985

1042

}

986

1043

1044

__attribute__((nonnull))

987

1045

static void resolve_callback(AvahiSServiceResolver *r,

988

1046

AvahiIfIndex interface,

989

1047

AvahiProtocol proto,

997

1055

AVAHI_GCC_UNUSED AvahiStringList *txt,

998

1056

AVAHI_GCC_UNUSED AvahiLookupResultFlags

999

1057

flags,

1000

AVAHI_GCC_UNUSED void* userdata){

1001

assert(r);

1058

void *mc){

1059

if(r == NULL){

1060

return;

1061

}

1002

1062

1003

1063

/* Called whenever a service has been resolved successfully or

1004

1064

timed out */

1013

1073

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

1014

1074

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

1015

1075

domain,

1016

avahi_strerror(avahi_server_errno(mc.server)));

1076

avahi_strerror(avahi_server_errno

1077

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

1017

1078

break;

1018

1079

1019

1080

case AVAHI_RESOLVER_FOUND:

1025

1086

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

1026

1087

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

1027

1088

}

1028

int ret = start_mandos_communication(ip, port, interface,

1029

avahi_proto_to_af(proto));

1089

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

1090

interface,

1091

avahi_proto_to_af(proto),

1092

mc);

1030

1093

if(ret == 0){

1031

avahi_simple_poll_quit(mc.simple_poll);

1094

avahi_simple_poll_quit(simple_poll);

1032

1095

} else {

1033

ret = add_server(ip, port, interface,

1034

avahi_proto_to_af(proto));

1096

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

1097

avahi_proto_to_af(proto),

1098

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

1099

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

1100

" list\n", name);

1101

}

1035

1102

}

1036

1103

}

1037

1104

}

1047

1114

const char *domain,

1048

1115

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1049

1116

flags,

1050

AVAHI_GCC_UNUSED void* userdata){

1051

assert(b);

1117

void *mc){

1118

if(b == NULL){

1119

return;

1120

}

1052

1121

1053

1122

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

1054

1123

is removed from the LAN */

1062

1131

case AVAHI_BROWSER_FAILURE:

1063

1132

1064

1133

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

1065

avahi_strerror(avahi_server_errno(mc.server)));

1066

avahi_simple_poll_quit(mc.simple_poll);

1134

avahi_strerror(avahi_server_errno

1135

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

1136

avahi_simple_poll_quit(simple_poll);

1067

1137

return;

1068

1138

1069

1139

case AVAHI_BROWSER_NEW:

1072

1142

the callback function is called the Avahi server will free the

1073

1143

resolver for us. */

1074

1144

1075

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

1076

name, type, domain, protocol, 0,

1077

resolve_callback, NULL) == NULL)

1145

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

1146

interface, protocol, name, type,

1147

domain, protocol, 0,

1148

resolve_callback, mc) == NULL)

1078

1149

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

1079

1150

" %s\n", name,

1080

avahi_strerror(avahi_server_errno(mc.server)));

1151

avahi_strerror(avahi_server_errno

1152

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

1081

1153

break;

1082

1154

1083

1155

case AVAHI_BROWSER_REMOVE:

1102

1174

signal_received = sig;

1103

1175

int old_errno = errno;

1104

1176

/* set main loop to exit */

1105

if(mc.simple_poll != NULL){

1106

avahi_simple_poll_quit(mc.simple_poll);

1177

if(simple_poll != NULL){

1178

avahi_simple_poll_quit(simple_poll);

1107

1179

}

1108

1180

errno = old_errno;

1109

1181

}

1110

1182

1183

__attribute__((nonnull, warn_unused_result))

1111

1184

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

1112

1185

int ret;

1186

error_t ret_errno;

1113

1187

1114

1188

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

1115

1189

if(s < 0){

1190

ret_errno = errno;

1116

1191

perror_plus("socket");

1192

errno = ret_errno;

1117

1193

return false;

1118

1194

}

1119

1195

strcpy(ifr->ifr_name, ifname);

1120

1196

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1121

1197

if(ret == -1){

1122

1198

if(debug){

1199

ret_errno = errno;

1123

1200

perror_plus("ioctl SIOCGIFFLAGS");

1201

errno = ret_errno;

1124

1202

}

1125

1203

return false;

1126

1204

}

1127

1205

return true;

1128

1206

}

1129

1207

1208

__attribute__((nonnull, warn_unused_result))

1130

1209

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

1131

1210

1132

1211

/* Reject the loopback device */

1174

1253

* corresponds to an acceptable network device.

1175

1254

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

1176

1255

*/

1256

__attribute__((nonnull, warn_unused_result))

1177

1257

int good_interface(const struct dirent *if_entry){

1178

1258

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

1179

1259

return 0;

1195

1275

}

1196

1276

1197

1277

/*

1198

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

1199

* corresponds to an acceptable network device which is up.

1200

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

1201

*/

1202

int up_interface(const struct dirent *if_entry){

1203

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

1204

return 0;

1205

}

1206

1207

struct ifreq ifr;

1208

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

1209

if(debug){

1210

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

1211

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

1212

}

1213

return 0;

1214

}

1215

1216

/* Reject down interfaces */

1217

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

1218

if(debug){

1219

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

1220

if_entry->d_name);

1221

}

1222

return 0;

1223

}

1224

1225

/* Reject non-running interfaces */

1226

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

1227

if(debug){

1228

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

1229

if_entry->d_name);

1230

}

1231

return 0;

1232

}

1233

1234

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

1235

return 0;

1236

}

1237

return 1;

1238

}

1239

1278

* This function determines if a network interface is up.

1279

*/

1280

__attribute__((nonnull, warn_unused_result))

1281

bool interface_is_up(const char *interface){

1282

struct ifreq ifr;

1283

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

1284

if(debug){

1285

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

1286

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

1287

}

1288

return false;

1289

}

1290

1291

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

1292

}

1293

1294

/*

1295

* This function determines if a network interface is running

1296

*/

1297

__attribute__((nonnull, warn_unused_result))

1298

bool interface_is_running(const char *interface){

1299

struct ifreq ifr;

1300

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

1301

if(debug){

1302

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

1303

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

1304

}

1305

return false;

1306

}

1307

1308

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

1309

}

1310

1311

__attribute__((nonnull, pure, warn_unused_result))

1240

1312

int notdotentries(const struct dirent *direntry){

1241

1313

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

1242

1314

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

1249

1321

}

1250

1322

1251

1323

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

1324

__attribute__((nonnull, warn_unused_result))

1252

1325

int runnable_hook(const struct dirent *direntry){

1253

1326

int ret;

1254

1327

size_t sret;

1262

1335

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

1263

1336

"abcdefghijklmnopqrstuvwxyz"

1264

1337

"0123456789"

1265

"_-");

1338

"_.-");

1266

1339

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

1267

1340

/* Contains non-allowed characters */

1268

1341

if(debug){

1286

1359

}

1287

1360

return 0;

1288

1361

}

1362

free(fullname);

1289

1363

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

1290

1364

/* Not a regular file */

1291

1365

if(debug){

1309

1383

return 1;

1310

1384

}

1311

1385

1312

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1386

__attribute__((nonnull, warn_unused_result))

1387

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1388

mandos_context *mc){

1313

1389

int ret;

1314

1390

struct timespec now;

1315

1391

struct timespec waited_time;

1316

1392

intmax_t block_time;

1317

1393

1318

1394

while(true){

1319

if(mc.current_server == NULL){

1320

if (debug){

1395

if(mc->current_server == NULL){

1396

if(debug){

1321

1397

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

1322

1398

" No timeout!\n");

1323

1399

}

1324

1400

ret = avahi_simple_poll_iterate(s, -1);

1325

1401

} else {

1326

if (debug){

1402

if(debug){

1327

1403

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

1328

1404

" it, or wait\n");

1329

1405

}

1336

1412

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

1337

1413

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

1338

1414

waited_time.tv_sec = (now.tv_sec

1339

- mc.current_server->last_seen.tv_sec);

1415

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

1340

1416

waited_time.tv_nsec = (now.tv_nsec

1341

- mc.current_server->last_seen.tv_nsec);

1417

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

1342

1418

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

1343

1419

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

1344

1420

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

1346

1422

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

1347

1423

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

1348

1424

1349

if (debug){

1425

if(debug){

1350

1426

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

1351

1427

block_time);

1352

1428

}

1353

1429

1354

1430

if(block_time <= 0){

1355

ret = start_mandos_communication(mc.current_server->ip,

1356

mc.current_server->port,

1357

mc.current_server->if_index,

1358

mc.current_server->af);

1431

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

1432

mc->current_server->port,

1433

mc->current_server->if_index,

1434

mc->current_server->af, mc);

1359

1435

if(ret == 0){

1360

avahi_simple_poll_quit(mc.simple_poll);

1436

avahi_simple_poll_quit(s);

1361

1437

return 0;

1362

1438

}

1363

1439

ret = clock_gettime(CLOCK_MONOTONIC,

1364

&mc.current_server->last_seen);

1440

&mc->current_server->last_seen);

1365

1441

if(ret == -1){

1366

1442

perror_plus("clock_gettime");

1367

1443

return -1;

1368

1444

}

1369

mc.current_server = mc.current_server->next;

1445

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

1370

1446

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

1371

1447

servers, but don't block */

1372

1448

}

1374

1450

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

1375

1451

}

1376

1452

if(ret != 0){

1377

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

1453

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

1378

1454

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

1379

1455

}

1380

1456

}

1381

1457

}

1382

1458

}

1383

1459

1384

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

1460

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

1461

__attribute__((warn_unused_result))

1462

error_t raise_privileges(void){

1463

error_t old_errno = errno;

1464

error_t ret_errno = 0;

1465

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

1466

ret_errno = errno;

1467

perror_plus("seteuid");

1468

}

1469

errno = old_errno;

1470

return ret_errno;

1471

}

1472

1473

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

1474

__attribute__((warn_unused_result))

1475

error_t raise_privileges_permanently(void){

1476

error_t old_errno = errno;

1477

error_t ret_errno = raise_privileges();

1478

if(ret_errno != 0){

1479

errno = old_errno;

1480

return ret_errno;

1481

}

1482

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

1483

ret_errno = errno;

1484

perror_plus("seteuid");

1485

}

1486

errno = old_errno;

1487

return ret_errno;

1488

}

1489

1490

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

1491

__attribute__((warn_unused_result))

1492

error_t lower_privileges(void){

1493

error_t old_errno = errno;

1494

error_t ret_errno = 0;

1495

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

1496

ret_errno = errno;

1497

perror_plus("seteuid");

1498

}

1499

errno = old_errno;

1500

return ret_errno;

1501

}

1502

1503

/* Lower privileges permanently */

1504

__attribute__((warn_unused_result))

1505

error_t lower_privileges_permanently(void){

1506

error_t old_errno = errno;

1507

error_t ret_errno = 0;

1508

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

1509

ret_errno = errno;

1510

perror_plus("setuid");

1511

}

1512

errno = old_errno;

1513

return ret_errno;

1514

}

1515

1516

__attribute__((nonnull))

1517

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

1385

1518

const float delay){

1386

1519

struct dirent **direntries;

1387

struct dirent *direntry;

1388

int ret;

1389

1520

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

1390

1521

alphasort);

1391

1522

if(numhooks == -1){

1392

perror_plus("scandir");

1523

if(errno == ENOENT){

1524

if(debug){

1525

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

1526

" found\n", hookdir);

1527

}

1528

} else {

1529

perror_plus("scandir");

1530

}

1393

1531

} else {

1532

struct dirent *direntry;

1533

int ret;

1394

1534

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

1395

1535

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

1396

1536

direntry = direntries[i];

1408

1548

if(hook_pid == 0){

1409

1549

/* Child */

1410

1550

/* Raise privileges */

1411

errno = 0;

1412

ret = seteuid(0);

1413

if(ret == -1){

1414

perror_plus("seteuid");

1415

}

1416

/* Raise privileges even more */

1417

errno = 0;

1418

ret = setuid(0);

1419

if(ret == -1){

1420

perror_plus("setuid");

1551

if(raise_privileges_permanently() != 0){

1552

perror_plus("Failed to raise privileges");

1553

_exit(EX_NOPERM);

1421

1554

}

1422

1555

/* Set group */

1423

1556

errno = 0;

1424

1557

ret = setgid(0);

1425

1558

if(ret == -1){

1426

1559

perror_plus("setgid");

1560

_exit(EX_NOPERM);

1427

1561

}

1428

1562

/* Reset supplementary groups */

1429

1563

errno = 0;

1430

1564

ret = setgroups(0, NULL);

1431

1565

if(ret == -1){

1432

1566

perror_plus("setgroups");

1433

}

1434

dup2(devnull, STDIN_FILENO);

1435

close(devnull);

1436

dup2(STDERR_FILENO, STDOUT_FILENO);

1567

_exit(EX_NOPERM);

1568

}

1569

ret = dup2(devnull, STDIN_FILENO);

1570

if(ret == -1){

1571

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

1572

_exit(EX_OSERR);

1573

}

1574

ret = close(devnull);

1575

if(ret == -1){

1576

perror_plus("close");

1577

_exit(EX_OSERR);

1578

}

1579

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1580

if(ret == -1){

1581

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

1582

_exit(EX_OSERR);

1583

}

1437

1584

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

1438

1585

if(ret == -1){

1439

1586

perror_plus("setenv");

1444

1591

perror_plus("setenv");

1445

1592

_exit(EX_OSERR);

1446

1593

}

1447

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

1594

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

1448

1595

if(ret == -1){

1449

1596

perror_plus("setenv");

1450

1597

_exit(EX_OSERR);

1455

1602

_exit(EX_OSERR);

1456

1603

}

1457

1604

char *delaystring;

1458

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

1605

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

1459

1606

if(ret == -1){

1460

1607

perror_plus("asprintf");

1461

1608

_exit(EX_OSERR);

1467

1614

_exit(EX_OSERR);

1468

1615

}

1469

1616

free(delaystring);

1470

ret = execl(fullname, direntry->d_name, mode, NULL);

1471

perror_plus("execl");

1617

if(connect_to != NULL){

1618

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

1619

if(ret == -1){

1620

perror_plus("setenv");

1621

_exit(EX_OSERR);

1622

}

1623

}

1624

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

1625

perror_plus("execl");

1626

_exit(EXIT_FAILURE);

1627

}

1472

1628

} else {

1473

1629

int status;

1474

1630

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

1505

1661

}

1506

1662

close(devnull);

1507

1663

}

1508

return true;

1664

}

1665

1666

__attribute__((nonnull, warn_unused_result))

1667

error_t bring_up_interface(const char *const interface,

1668

const float delay){

1669

error_t old_errno = errno;

1670

int ret;

1671

struct ifreq network;

1672

unsigned int if_index = if_nametoindex(interface);

1673

if(if_index == 0){

1674

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

1675

errno = old_errno;

1676

return ENXIO;

1677

}

1678

1679

if(quit_now){

1680

errno = old_errno;

1681

return EINTR;

1682

}

1683

1684

if(not interface_is_up(interface)){

1685

error_t ret_errno = 0, ioctl_errno = 0;

1686

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

1687

ret_errno = errno;

1688

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

1689

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

1690

errno = old_errno;

1691

return ret_errno;

1692

}

1693

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

1694

1695

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

1696

if(sd == -1){

1697

ret_errno = errno;

1698

perror_plus("socket");

1699

errno = old_errno;

1700

return ret_errno;

1701

}

1702

1703

if(quit_now){

1704

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

1705

if(ret == -1){

1706

perror_plus("close");

1707

}

1708

errno = old_errno;

1709

return EINTR;

1710

}

1711

1712

if(debug){

1713

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

1714

interface);

1715

}

1716

1717

/* Raise privileges */

1718

ret_errno = raise_privileges();

1719

if(ret_errno != 0){

1720

perror_plus("Failed to raise privileges");

1721

}

1722

1723

#ifdef __linux__

1724

int ret_linux;

1725

bool restore_loglevel = false;

1726

if(ret_errno == 0){

1727

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1728

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

1729

ret_linux = klogctl(8, NULL, 5);

1730

if(ret_linux == -1){

1731

perror_plus("klogctl");

1732

} else {

1733

restore_loglevel = true;

1734

}

1735

}

1736

#endif /* __linux__ */

1737

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

1738

ioctl_errno = errno;

1739

#ifdef __linux__

1740

if(restore_loglevel){

1741

ret_linux = klogctl(7, NULL, 0);

1742

if(ret_linux == -1){

1743

perror_plus("klogctl");

1744

}

1745

}

1746

#endif /* __linux__ */

1747

1748

/* If raise_privileges() succeeded above */

1749

if(ret_errno == 0){

1750

/* Lower privileges */

1751

ret_errno = lower_privileges();

1752

if(ret_errno != 0){

1753

errno = ret_errno;

1754

perror_plus("Failed to lower privileges");

1755

}

1756

}

1757

1758

/* Close the socket */

1759

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

1760

if(ret == -1){

1761

perror_plus("close");

1762

}

1763

1764

if(ret_setflags == -1){

1765

errno = ioctl_errno;

1766

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1767

errno = old_errno;

1768

return ioctl_errno;

1769

}

1770

} else if(debug){

1771

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

1772

interface);

1773

}

1774

1775

/* Sleep checking until interface is running.

1776

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

1777

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

1778

if(interface_is_running(interface)){

1779

break;

1780

}

1781

struct timespec sleeptime = { .tv_nsec = 250000000 };

1782

ret = nanosleep(&sleeptime, NULL);

1783

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

1784

perror_plus("nanosleep");

1785

}

1786

}

1787

1788

errno = old_errno;

1789

return 0;

1790

}

1791

1792

__attribute__((nonnull, warn_unused_result))

1793

error_t take_down_interface(const char *const interface){

1794

error_t old_errno = errno;

1795

struct ifreq network;

1796

unsigned int if_index = if_nametoindex(interface);

1797

if(if_index == 0){

1798

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

1799

errno = old_errno;

1800

return ENXIO;

1801

}

1802

if(interface_is_up(interface)){

1803

error_t ret_errno = 0, ioctl_errno = 0;

1804

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

1805

ret_errno = errno;

1806

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

1807

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

1808

errno = old_errno;

1809

return ret_errno;

1810

}

1811

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

1812

1813

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

1814

if(sd == -1){

1815

ret_errno = errno;

1816

perror_plus("socket");

1817

errno = old_errno;

1818

return ret_errno;

1819

}

1820

1821

if(debug){

1822

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

1823

interface);

1824

}

1825

1826

/* Raise privileges */

1827

ret_errno = raise_privileges();

1828

if(ret_errno != 0){

1829

perror_plus("Failed to raise privileges");

1830

}

1831

1832

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

1833

ioctl_errno = errno;

1834

1835

/* If raise_privileges() succeeded above */

1836

if(ret_errno == 0){

1837

/* Lower privileges */

1838

ret_errno = lower_privileges();

1839

if(ret_errno != 0){

1840

errno = ret_errno;

1841

perror_plus("Failed to lower privileges");

1842

}

1843

}

1844

1845

/* Close the socket */

1846

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

1847

if(ret == -1){

1848

perror_plus("close");

1849

}

1850

1851

if(ret_setflags == -1){

1852

errno = ioctl_errno;

1853

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1854

errno = old_errno;

1855

return ioctl_errno;

1856

}

1857

} else if(debug){

1858

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

1859

interface);

1860

}

1861

1862

errno = old_errno;

1863

return 0;

1509

1864

}

1510

1865

1511

1866

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

1867

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

1868

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

1869

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

1870

.interfaces = NULL, .interfaces_size = 0 };

1512

1871

AvahiSServiceBrowser *sb = NULL;

1513

int error;

1872

error_t ret_errno;

1514

1873

int ret;

1515

1874

intmax_t tmpmax;

1516

1875

char *tmp;

1517

1876

int exitcode = EXIT_SUCCESS;

1518

const char *interface = "";

1519

struct ifreq network;

1520

int sd = -1;

1521

bool take_down_interface = false;

1522

uid_t uid;

1523

gid_t gid;

1524

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

1525

bool tempdir_created = false;

1877

char *interfaces_to_take_down = NULL;

1878

size_t interfaces_to_take_down_size = 0;

1879

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

1880

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

1881

char *tempdir = NULL;

1526

1882

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1527

1883

const char *seckey = PATHDIR "/" SECKEY;

1528

1884

const char *pubkey = PATHDIR "/" PUBKEY;

1885

char *interfaces_hooks = NULL;

1529

1886

1530

1887

bool gnutls_initialized = false;

1531

1888

bool gpgme_initialized = false;

1593

1950

.group = 2 },

1594

1951

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

1595

1952

.arg = "SECONDS",

1596

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

1953

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

1597

1954

.group = 2 },

1598

1955

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

1599

1956

.arg = "DIR",

1622

1979

connect_to = arg;

1623

1980

break;

1624

1981

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

1625

interface = arg;

1982

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

1983

arg, (int)',');

1984

if(ret_errno != 0){

1985

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

1986

}

1626

1987

break;

1627

1988

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

1628

1989

seckey = arg;

1671

2032

argp_state_help(state, state->out_stream,

1672

2033

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1673

2034

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

1674

fprintf_plus(state->out_stream,

1675

"Mandos plugin mandos-client: ");

1676

2035

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

1677

2036

exit(argp_err_exit_status);

1678

2037

break;

1707

2066

/* Work around Debian bug #633582:

1708

2067

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

1709

2068

1710

/* Re-raise priviliges */

1711

errno = 0;

1712

ret = seteuid(0);

1713

if(ret == -1){

1714

perror_plus("seteuid");

2069

/* Re-raise privileges */

2070

ret_errno = raise_privileges();

2071

if(ret_errno != 0){

2072

errno = ret_errno;

2073

perror_plus("Failed to raise privileges");

1715

2074

} else {

1716

2075

struct stat st;

1717

2076

1758

2117

}

1759

2118

1760

2119

/* Lower privileges */

1761

errno = 0;

1762

ret = seteuid(uid);

1763

if(ret == -1){

1764

perror_plus("seteuid");

2120

ret_errno = lower_privileges();

2121

if(ret_errno != 0){

2122

errno = ret_errno;

2123

perror_plus("Failed to lower privileges");

2124

}

2125

}

2126

}

2127

2128

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

2129

{

2130

char *interface = NULL;

2131

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

2132

interface))){

2133

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

2134

and if_nametoindex(interface) == 0){

2135

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

2136

fprintf_plus(stderr, "Not using nonexisting interface"

2137

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

2138

}

2139

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

2140

interface = NULL;

1765

2141

}

1766

2142

}

1767

2143

}

1768

2144

1769

2145

/* Run network hooks */

1770

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

1771

goto end;

2146

{

2147

if(mc.interfaces != NULL){

2148

interfaces_hooks = malloc(mc.interfaces_size);

2149

if(interfaces_hooks == NULL){

2150

perror_plus("malloc");

2151

goto end;

2152

}

2153

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

2154

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

2155

}

2156

run_network_hooks("start", interfaces_hooks != NULL ?

2157

interfaces_hooks : "", delay);

1772

2158

}

1773

2159

1774

2160

if(not debug){

1775

2161

avahi_set_log_function(empty_log);

1776

2162

}

1777

2163

1778

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

1779

struct dirent **direntries;

1780

/* First look for interfaces that are up */

1781

ret = scandir(sys_class_net, &direntries, up_interface,

1782

alphasort);

1783

if(ret == 0){

1784

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

1785

free(direntries);

1786

ret = scandir(sys_class_net, &direntries, good_interface,

1787

alphasort);

1788

}

1789

if(ret >= 1){

1790

/* Pick the first interface returned */

1791

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

1792

if(debug){

1793

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

1794

}

1795

if(interface == NULL){

1796

perror_plus("malloc");

1797

free(direntries);

1798

exitcode = EXIT_FAILURE;

1799

goto end;

1800

}

1801

free(direntries);

1802

} else {

1803

free(direntries);

1804

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

1805

exitcode = EXIT_FAILURE;

1806

goto end;

1807

}

1808

}

1809

1810

2164

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

1811

2165

from the signal handler */

1812

2166

/* Initialize the pseudo-RNG for Avahi */

1813

2167

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

1814

mc.simple_poll = avahi_simple_poll_new();

1815

if(mc.simple_poll == NULL){

2168

simple_poll = avahi_simple_poll_new();

2169

if(simple_poll == NULL){

1816

2170

fprintf_plus(stderr,

1817

2171

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

1818

2172

exitcode = EX_UNAVAILABLE;

1882

2236

}

1883

2237

}

1884

2238

1885

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

1886

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

1887

if_index = (AvahiIfIndex) if_nametoindex(interface);

1888

if(if_index == 0){

1889

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

1890

exitcode = EX_UNAVAILABLE;

1891

goto end;

1892

}

1893

1894

if(quit_now){

1895

goto end;

1896

}

1897

1898

/* Re-raise priviliges */

1899

errno = 0;

1900

ret = seteuid(0);

1901

if(ret == -1){

1902

perror_plus("seteuid");

1903

}

1904

1905

#ifdef __linux__

1906

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1907

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

1908

ret = klogctl(8, NULL, 5);

1909

bool restore_loglevel = true;

1910

if(ret == -1){

1911

restore_loglevel = false;

1912

perror_plus("klogctl");

1913

}

1914

#endif /* __linux__ */

1915

1916

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1917

if(sd < 0){

1918

perror_plus("socket");

1919

exitcode = EX_OSERR;

1920

#ifdef __linux__

1921

if(restore_loglevel){

1922

ret = klogctl(7, NULL, 0);

1923

if(ret == -1){

1924

perror_plus("klogctl");

1925

}

1926

}

1927

#endif /* __linux__ */

1928

/* Lower privileges */

1929

errno = 0;

1930

ret = seteuid(uid);

1931

if(ret == -1){

1932

perror_plus("seteuid");

1933

}

1934

goto end;

1935

}

1936

strcpy(network.ifr_name, interface);

1937

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

1938

if(ret == -1){

1939

perror_plus("ioctl SIOCGIFFLAGS");

1940

#ifdef __linux__

1941

if(restore_loglevel){

1942

ret = klogctl(7, NULL, 0);

1943

if(ret == -1){

1944

perror_plus("klogctl");

1945

}

1946

}

1947

#endif /* __linux__ */

1948

exitcode = EX_OSERR;

1949

/* Lower privileges */

1950

errno = 0;

1951

ret = seteuid(uid);

1952

if(ret == -1){

1953

perror_plus("seteuid");

1954

}

1955

goto end;

1956

}

1957

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

1958

network.ifr_flags |= IFF_UP;

1959

take_down_interface = true;

1960

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

1961

if(ret == -1){

1962

take_down_interface = false;

1963

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1964

exitcode = EX_OSERR;

1965

#ifdef __linux__

1966

if(restore_loglevel){

1967

ret = klogctl(7, NULL, 0);

1968

if(ret == -1){

1969

perror_plus("klogctl");

2239

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

2240

if(mc.interfaces == NULL){

2241

struct dirent **direntries;

2242

/* Look for any good interfaces */

2243

ret = scandir(sys_class_net, &direntries, good_interface,

2244

alphasort);

2245

if(ret >= 1){

2246

/* Add all found interfaces to interfaces list */

2247

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

2248

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

2249

direntries[i]->d_name);

2250

if(ret_errno != 0){

2251

errno = ret_errno;

2252

perror_plus("argz_add");

2253

continue;

2254

}

2255

if(debug){

2256

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

2257

direntries[i]->d_name);

2258

}

2259

}

2260

free(direntries);

2261

} else {

2262

free(direntries);

2263

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

2264

exitcode = EXIT_FAILURE;

2265

goto end;

2266

}

2267

}

2268

2269

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

2270

{

2271

char *interface = NULL;

2272

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

2273

interface))){

2274

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

2275

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

2276

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

2277

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

2278

interface);

2279

interface = NULL;

2280

while((interface = argz_next(mc.interfaces,

2281

mc.interfaces_size, interface))){

2282

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

2283

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

2284

interface);

2285

interface = NULL;

1970

2286

}

1971

2287

}

1972

#endif /* __linux__ */

1973

/* Lower privileges */

1974

errno = 0;

1975

ret = seteuid(uid);

1976

if(ret == -1){

1977

perror_plus("seteuid");

1978

}

1979

goto end;

1980

}

1981

}

1982

/* Sleep checking until interface is running.

1983

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

1984

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

1985

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

1986

if(ret == -1){

1987

perror_plus("ioctl SIOCGIFFLAGS");

1988

} else if(network.ifr_flags & IFF_RUNNING){

1989

2288

break;

1990

2289

}

1991

struct timespec sleeptime = { .tv_nsec = 250000000 };

1992

ret = nanosleep(&sleeptime, NULL);

1993

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

1994

perror_plus("nanosleep");

1995

}

1996

}

1997

if(not take_down_interface){

1998

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

1999

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

2000

if(ret == -1){

2001

perror_plus("close");

2002

}

2003

}

2004

#ifdef __linux__

2005

if(restore_loglevel){

2006

/* Restores kernel loglevel to default */

2007

ret = klogctl(7, NULL, 0);

2008

if(ret == -1){

2009

perror_plus("klogctl");

2010

}

2011

}

2012

#endif /* __linux__ */

2013

/* Lower privileges */

2014

errno = 0;

2015

/* Lower privileges */

2016

ret = seteuid(uid);

2017

if(ret == -1){

2018

perror_plus("seteuid");

2019

}

2290

bool interface_was_up = interface_is_up(interface);

2291

errno = bring_up_interface(interface, delay);

2292

if(not interface_was_up){

2293

if(errno != 0){

2294

perror_plus("Failed to bring up interface");

2295

} else {

2296

errno = argz_add(&interfaces_to_take_down,

2297

&interfaces_to_take_down_size,

2298

interface);

2299

if(errno != 0){

2300

perror_plus("argz_add");

2301

}

2302

}

2303

}

2304

}

2305

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

2306

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

2307

}

2308

}

2309

2310

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

2311

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

2312

if(debug){

2313

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

2314

mc.interfaces);

2315

}

2316

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

2020

2317

}

2021

2318

2022

2319

if(quit_now){

2023

2320

goto end;

2024

2321

}

2025

2322

2026

ret = init_gnutls_global(pubkey, seckey);

2323

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

2027

2324

if(ret == -1){

2028

2325

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

2029

2326

exitcode = EX_UNAVAILABLE;

2036

2333

goto end;

2037

2334

}

2038

2335

2039

if(mkdtemp(tempdir) == NULL){

2336

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

2337

tempdir = mkdtemp(run_tempdir);

2338

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

2339

if(debug){

2340

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

2341

run_tempdir, old_tempdir);

2342

}

2343

tempdir = mkdtemp(old_tempdir);

2344

}

2345

if(tempdir == NULL){

2040

2346

perror_plus("mkdtemp");

2041

2347

goto end;

2042

2348

}

2043

tempdir_created = true;

2044

2349

2045

2350

if(quit_now){

2046

2351

goto end;

2047

2352

}

2048

2353

2049

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

2354

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

2050

2355

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

2051

2356

exitcode = EX_UNAVAILABLE;

2052

2357

goto end;

2062

2367

/* Connect directly, do not use Zeroconf */

2063

2368

/* (Mainly meant for debugging) */

2064

2369

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

2370

2065

2371

if(address == NULL){

2066

2372

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

2067

2373

exitcode = EX_USAGE;

2072

2378

goto end;

2073

2379

}

2074

2380

2075

uint16_t port;

2381

in_port_t port;

2076

2382

errno = 0;

2077

2383

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

2078

2384

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

2079

or tmpmax != (uint16_t)tmpmax){

2385

or tmpmax != (in_port_t)tmpmax){

2080

2386

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

2081

2387

exitcode = EX_USAGE;

2082

2388

goto end;

2083

2389

}

2084

2390

2085

2391

if(quit_now){

2086

2392

goto end;

2087

2393

}

2088

2394

2089

port = (uint16_t)tmpmax;

2395

port = (in_port_t)tmpmax;

2090

2396

*address = '\0';

2091

2397

/* Colon in address indicates IPv6 */

2092

2398

int af;

2108

2414

}

2109

2415

2110

2416

while(not quit_now){

2111

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

2417

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

2418

&mc);

2112

2419

if(quit_now or ret == 0){

2113

2420

break;

2114

2421

}

2116

2423

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

2117

2424

(int)retry_interval);

2118

2425

}

2119

sleep((int)retry_interval);

2426

sleep((unsigned int)retry_interval);

2120

2427

}

2121

2428

2122

if (not quit_now){

2429

if(not quit_now){

2123

2430

exitcode = EXIT_SUCCESS;

2124

2431

}

2125

2432

2140

2447

config.publish_domain = 0;

2141

2448

2142

2449

/* Allocate a new server */

2143

mc.server = avahi_server_new(avahi_simple_poll_get

2144

(mc.simple_poll), &config, NULL,

2145

NULL, &error);

2450

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2451

&config, NULL, NULL, &ret_errno);

2146

2452

2147

2453

/* Free the Avahi configuration data */

2148

2454

avahi_server_config_free(&config);

2151

2457

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

2152

2458

if(mc.server == NULL){

2153

2459

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

2154

avahi_strerror(error));

2460

avahi_strerror(ret_errno));

2155

2461

exitcode = EX_UNAVAILABLE;

2156

2462

goto end;

2157

2463

}

2163

2469

/* Create the Avahi service browser */

2164

2470

sb = avahi_s_service_browser_new(mc.server, if_index,

2165

2471

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2166

NULL, 0, browse_callback, NULL);

2472

NULL, 0, browse_callback,

2473

(void *)&mc);

2167

2474

if(sb == NULL){

2168

2475

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

2169

2476

avahi_strerror(avahi_server_errno(mc.server)));

2180

2487

if(debug){

2181

2488

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

2182

2489

}

2183

2184

ret = avahi_loop_with_timeout(mc.simple_poll,

2185

(int)(retry_interval * 1000));

2490

2491

ret = avahi_loop_with_timeout(simple_poll,

2492

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

2186

2493

if(debug){

2187

2494

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

2188

2495

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

2195

2502

}

2196

2503

2197

2504

/* Cleanup things */

2505

free(mc.interfaces);

2506

2198

2507

if(sb != NULL)

2199

2508

avahi_s_service_browser_free(sb);

2200

2509

2201

2510

if(mc.server != NULL)

2202

2511

avahi_server_free(mc.server);

2203

2512

2204

if(mc.simple_poll != NULL)

2205

avahi_simple_poll_free(mc.simple_poll);

2513

if(simple_poll != NULL)

2514

avahi_simple_poll_free(simple_poll);

2206

2515

2207

2516

if(gnutls_initialized){

2208

2517

gnutls_certificate_free_credentials(mc.cred);

2225

2534

}

2226

2535

}

2227

2536

2228

/* Run network hooks */

2229

run_network_hooks("stop", interface, delay);

2230

2231

/* Re-raise priviliges */

2537

/* Re-raise privileges */

2232

2538

{

2233

errno = 0;

2234

ret = seteuid(0);

2235

if(ret == -1){

2236

perror_plus("seteuid");

2539

ret_errno = raise_privileges();

2540

if(ret_errno != 0){

2541

perror_plus("Failed to raise privileges");

2542

} else {

2543

2544

/* Run network hooks */

2545

run_network_hooks("stop", interfaces_hooks != NULL ?

2546

interfaces_hooks : "", delay);

2547

2548

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

2549

{

2550

char *interface = NULL;

2551

while((interface=argz_next(interfaces_to_take_down,

2552

interfaces_to_take_down_size,

2553

interface))){

2554

ret_errno = take_down_interface(interface);

2555

if(ret_errno != 0){

2556

errno = ret_errno;

2557

perror_plus("Failed to take down interface");

2558

}

2559

}

2560

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

2561

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

2562

" down\n");

2563

}

2564

}

2237

2565

}

2238

2566

2239

/* Take down the network interface */

2240

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

2241

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

2242

if(ret == -1){

2243

perror_plus("ioctl SIOCGIFFLAGS");

2244

} else if(network.ifr_flags & IFF_UP){

2245

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

2246

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

2247

if(ret == -1){

2248

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2249

}

2250

}

2251

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

2252

if(ret == -1){

2253

perror_plus("close");

2254

}

2567

ret_errno = lower_privileges_permanently();

2568

if(ret_errno != 0){

2569

perror_plus("Failed to lower privileges permanently");

2255

2570

}

2256

2571

}

2257

/* Lower privileges permanently */

2258

errno = 0;

2259

ret = setuid(uid);

2260

if(ret == -1){

2261

perror_plus("setuid");

2262

}

2572

2573

free(interfaces_to_take_down);

2574

free(interfaces_hooks);

2263

2575

2264

2576

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

2265

if(tempdir_created){

2577

if(tempdir != NULL){

2266

2578

struct dirent **direntries = NULL;

2267

2579

struct dirent *direntry = NULL;

2268

2580

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

2269

2581

alphasort);

2270

if (numentries > 0){

2582

if(numentries > 0){

2271

2583

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

2272

2584

direntry = direntries[i];

2273

2585

char *fullname = NULL;

2285

2597

free(fullname);

2286

2598

}

2287

2599

}

2288

2600

2289

2601

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

2290

2602

free(direntries);

2291

if (numentries == -1){

2603

if(numentries == -1){

2292

2604

perror_plus("scandir");

2293

2605

}

2294

2606

ret = rmdir(tempdir);