/mandos/release : revision 237.7.245

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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@fukt.bsnet.se>.

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* Contact the authors at <mandos@recompile.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

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#endif /* not _LARGEFILE_SOURCE */

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#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

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#endif

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#endif /* not _FILE_OFFSET_BITS */

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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(), remove() */

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

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stdout, ferror() */

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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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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() */

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

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

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SIOCSIFFLAGS, if_indextoname(),

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*/

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

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

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setgid(), pause() */

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

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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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#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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118

init_gnutls_session(),

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119

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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133

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

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134

#define SECKEY "seckey.txt"

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135

#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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139

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@fukt.bsnet.se>";

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

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

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char *connect_to = NULL;

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const char *hookdir = HOOKDIR;

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int hookdir_fd = -1;

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uid_t uid = 65534;

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gid_t gid = 65534;

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

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typedef struct server{

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const char *ip;

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in_port_t port;

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AvahiIfIndex if_index;

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int af;

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struct timespec last_seen;

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struct server *next;

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struct server *prev;

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} server;

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

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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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164

unsigned int dh_bits;

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gnutls_dh_params_t dh_params;

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166

const char *priority;

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167

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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172

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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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/* 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 */

180

void perror_plus(const char *print_text){

181

int e = errno;

182

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);

186

}

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188

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

189

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

190

va_list ap;

191

va_start (ap, format);

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193

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

194

program_invocation_short_name));

195

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

196

}

197

152

198

/*

153

199

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

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200

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

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201

* "buffer_length" is how much is already used.

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202

*/

203

__attribute__((nonnull, warn_unused_result))

157

204

size_t incbuffer(char **buffer, size_t buffer_length,

158

size_t buffer_capacity){

205

size_t buffer_capacity){

159

206

if(buffer_length + BUFFER_SIZE > buffer_capacity){

160

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

161

if(buffer == NULL){

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;

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*buffer = NULL;

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return 0;

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}

215

*buffer = new_buf;

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buffer_capacity += BUFFER_SIZE;

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217

}

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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 ret;

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

227

if(new_server == NULL){

228

perror_plus("malloc");

229

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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.if_index = if_index,

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.af = af };

235

if(new_server->ip == NULL){

236

perror_plus("strdup");

237

return false;

238

}

239

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

240

if(ret == -1){

241

perror_plus("clock_gettime");

242

return false;

243

}

244

/* Special case of first server */

245

if(*current_server == NULL){

246

new_server->next = new_server;

247

new_server->prev = new_server;

248

*current_server = new_server;

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} else {

250

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

251

new_server->next = *current_server;

252

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

253

new_server->prev->next = new_server;

254

(*current_server)->prev = new_server;

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}

256

return true;

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}

258

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/*

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260

* Initialize GPGME.

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261

*/

172

static bool init_gpgme(const char *seckey,

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const char *pubkey, const char *tempdir){

262

__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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269

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/*

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

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272

*/

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bool import_key(const char *filename){

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bool import_key(const char * const filename){

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274

int ret;

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int fd;

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gpgme_data_t pgp_data;

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

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if(fd == -1){

188

perror("open");

280

perror_plus("open");

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return false;

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282

}

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rc = gpgme_data_new_from_fd(&pgp_data, fd);

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285

if(rc != GPG_ERR_NO_ERROR){

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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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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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return false;

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289

}

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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){

201

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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fprintf_plus(stderr, "bad gpgme_op_import: %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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ret = (int)TEMP_FAILURE_RETRY(close(fd));

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299

if(ret == -1){

208

perror("close");

300

perror_plus("close");

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301

}

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gpgme_data_release(pgp_data);

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return true;

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}

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if(debug){

215

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

307

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

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}

217

309

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310

/* Init GPGME */

219

311

gpgme_check_version(NULL);

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312

rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

221

313

if(rc != GPG_ERR_NO_ERROR){

222

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

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gpgme_strsource(rc), gpgme_strerror(rc));

314

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

315

gpgme_strsource(rc), gpgme_strerror(rc));

224

316

return false;

225

317

}

226

318

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

319

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

228

320

rc = gpgme_get_engine_info(&engine_info);

229

321

if(rc != GPG_ERR_NO_ERROR){

230

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

231

gpgme_strsource(rc), gpgme_strerror(rc));

322

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

323

gpgme_strsource(rc), gpgme_strerror(rc));

232

324

return false;

233

325

}

234

326

while(engine_info != NULL){

240

332

engine_info = engine_info->next;

241

333

}

242

334

if(engine_info == NULL){

243

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

335

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

336

tempdir);

244

337

return false;

245

338

}

246

339

247

340

/* Create new GPGME "context" */

248

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

341

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

249

342

if(rc != GPG_ERR_NO_ERROR){

250

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

251

gpgme_strsource(rc), gpgme_strerror(rc));

343

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

344

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

345

gpgme_strerror(rc));

252

346

return false;

253

347

}

254

348

263

357

* Decrypt OpenPGP data.

264

358

* Returns -1 on error

265

359

*/

360

__attribute__((nonnull, warn_unused_result))

266

361

static ssize_t pgp_packet_decrypt(const char *cryptotext,

267

362

size_t crypto_size,

268

char **plaintext){

363

char **plaintext,

364

mandos_context *mc){

269

365

gpgme_data_t dh_crypto, dh_plain;

270

366

gpgme_error_t rc;

271

367

ssize_t ret;

273

369

ssize_t plaintext_length = 0;

274

370

275

371

if(debug){

276

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

372

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

277

373

}

278

374

279

375

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

280

376

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

281

377

0);

282

378

if(rc != GPG_ERR_NO_ERROR){

283

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

284

gpgme_strsource(rc), gpgme_strerror(rc));

379

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

380

gpgme_strsource(rc), gpgme_strerror(rc));

285

381

return -1;

286

382

}

287

383

288

384

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

289

385

rc = gpgme_data_new(&dh_plain);

290

386

if(rc != GPG_ERR_NO_ERROR){

291

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

292

gpgme_strsource(rc), gpgme_strerror(rc));

387

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

388

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

389

gpgme_strsource(rc), gpgme_strerror(rc));

293

390

gpgme_data_release(dh_crypto);

294

391

return -1;

295

392

}

296

393

297

394

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

298

395

data buffer */

299

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

396

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

300

397

if(rc != GPG_ERR_NO_ERROR){

301

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

302

gpgme_strsource(rc), gpgme_strerror(rc));

398

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

399

gpgme_strsource(rc), gpgme_strerror(rc));

303

400

plaintext_length = -1;

304

401

if(debug){

305

402

gpgme_decrypt_result_t result;

306

result = gpgme_op_decrypt_result(mc.ctx);

403

result = gpgme_op_decrypt_result(mc->ctx);

307

404

if(result == NULL){

308

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

405

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

309

406

} else {

310

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

311

result->unsupported_algorithm);

312

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

313

result->wrong_key_usage);

407

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

408

result->unsupported_algorithm);

409

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

410

result->wrong_key_usage);

314

411

if(result->file_name != NULL){

315

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

412

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

316

413

}

317

414

gpgme_recipient_t recipient;

318

415

recipient = result->recipients;

319

416

while(recipient != NULL){

320

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

321

gpgme_pubkey_algo_name(recipient->pubkey_algo));

322

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

323

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

324

recipient->status == GPG_ERR_NO_SECKEY

325

? "No" : "Yes");

417

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

418

gpgme_pubkey_algo_name

419

(recipient->pubkey_algo));

420

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

421

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

422

recipient->status == GPG_ERR_NO_SECKEY

423

? "No" : "Yes");

326

424

recipient = recipient->next;

327

425

}

328

426

}

331

429

}

332

430

333

431

if(debug){

334

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

432

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

335

433

}

336

434

337

435

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

338

436

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

339

perror("gpgme_data_seek");

437

perror_plus("gpgme_data_seek");

340

438

plaintext_length = -1;

341

439

goto decrypt_end;

342

440

}

344

442

*plaintext = NULL;

345

443

while(true){

346

444

plaintext_capacity = incbuffer(plaintext,

347

(size_t)plaintext_length,

348

plaintext_capacity);

445

(size_t)plaintext_length,

446

plaintext_capacity);

349

447

if(plaintext_capacity == 0){

350

perror("incbuffer");

351

plaintext_length = -1;

352

goto decrypt_end;

448

perror_plus("incbuffer");

449

plaintext_length = -1;

450

goto decrypt_end;

353

451

}

354

452

355

453

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

360

458

break;

361

459

}

362

460

if(ret < 0){

363

perror("gpgme_data_read");

461

perror_plus("gpgme_data_read");

364

462

plaintext_length = -1;

365

463

goto decrypt_end;

366

464

}

368

466

}

369

467

370

468

if(debug){

371

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

469

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

372

470

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

373

471

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

374

472

}

385

483

return plaintext_length;

386

484

}

387

485

388

static const char * safer_gnutls_strerror(int value){

389

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

390

-Wunreachable-code */

486

__attribute__((warn_unused_result))

487

static const char *safer_gnutls_strerror(int value){

488

const char *ret = gnutls_strerror(value);

391

489

if(ret == NULL)

392

490

ret = "(unknown)";

393

491

return ret;

394

492

}

395

493

396

494

/* GnuTLS log function callback */

495

__attribute__((nonnull))

397

496

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

398

497

const char* string){

399

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

498

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

400

499

}

401

500

501

__attribute__((nonnull, warn_unused_result))

402

502

static int init_gnutls_global(const char *pubkeyfilename,

403

const char *seckeyfilename){

503

const char *seckeyfilename,

504

mandos_context *mc){

404

505

int ret;

405

506

406

507

if(debug){

407

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

508

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

408

509

}

409

510

410

511

ret = gnutls_global_init();

411

512

if(ret != GNUTLS_E_SUCCESS){

412

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

413

safer_gnutls_strerror(ret));

513

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

514

safer_gnutls_strerror(ret));

414

515

return -1;

415

516

}

416

517

423

524

}

424

525

425

526

/* OpenPGP credentials */

426

gnutls_certificate_allocate_credentials(&mc.cred);

527

ret = gnutls_certificate_allocate_credentials(&mc->cred);

427

528

if(ret != GNUTLS_E_SUCCESS){

428

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

429

from

430

-Wunreachable-code

431

*/

432

safer_gnutls_strerror(ret));

529

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

530

safer_gnutls_strerror(ret));

433

531

gnutls_global_deinit();

434

532

return -1;

435

533

}

436

534

437

535

if(debug){

438

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

439

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

440

seckeyfilename);

536

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

537

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

538

pubkeyfilename,

539

seckeyfilename);

441

540

}

442

541

443

542

ret = gnutls_certificate_set_openpgp_key_file

444

(mc.cred, pubkeyfilename, seckeyfilename,

543

(mc->cred, pubkeyfilename, seckeyfilename,

445

544

GNUTLS_OPENPGP_FMT_BASE64);

446

545

if(ret != GNUTLS_E_SUCCESS){

447

fprintf(stderr,

448

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

449

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

450

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

451

safer_gnutls_strerror(ret));

546

fprintf_plus(stderr,

547

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

548

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

549

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

550

safer_gnutls_strerror(ret));

452

551

goto globalfail;

453

552

}

454

553

455

554

/* GnuTLS server initialization */

456

ret = gnutls_dh_params_init(&mc.dh_params);

555

ret = gnutls_dh_params_init(&mc->dh_params);

457

556

if(ret != GNUTLS_E_SUCCESS){

458

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

459

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

557

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

558

" initialization: %s\n",

559

safer_gnutls_strerror(ret));

460

560

goto globalfail;

461

561

}

462

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

562

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

463

563

if(ret != GNUTLS_E_SUCCESS){

464

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

465

safer_gnutls_strerror(ret));

564

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

565

safer_gnutls_strerror(ret));

466

566

goto globalfail;

467

567

}

468

568

469

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

569

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

470

570

471

571

return 0;

472

572

473

573

globalfail:

474

574

475

gnutls_certificate_free_credentials(mc.cred);

575

gnutls_certificate_free_credentials(mc->cred);

476

576

gnutls_global_deinit();

477

gnutls_dh_params_deinit(mc.dh_params);

577

gnutls_dh_params_deinit(mc->dh_params);

478

578

return -1;

479

579

}

480

580

481

static int init_gnutls_session(gnutls_session_t *session){

581

__attribute__((nonnull, warn_unused_result))

582

static int init_gnutls_session(gnutls_session_t *session,

583

mandos_context *mc){

482

584

int ret;

483

585

/* GnuTLS session creation */

484

586

do {

488

590

}

489

591

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

490

592

if(ret != GNUTLS_E_SUCCESS){

491

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

492

safer_gnutls_strerror(ret));

593

fprintf_plus(stderr,

594

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

595

safer_gnutls_strerror(ret));

493

596

}

494

597

495

598

{

496

599

const char *err;

497

600

do {

498

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

601

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

499

602

if(quit_now){

500

603

gnutls_deinit(*session);

501

604

return -1;

502

605

}

503

606

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

504

607

if(ret != GNUTLS_E_SUCCESS){

505

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

506

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

507

safer_gnutls_strerror(ret));

608

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

609

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

610

safer_gnutls_strerror(ret));

508

611

gnutls_deinit(*session);

509

612

return -1;

510

613

}

512

615

513

616

do {

514

617

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

515

mc.cred);

618

mc->cred);

516

619

if(quit_now){

517

620

gnutls_deinit(*session);

518

621

return -1;

519

622

}

520

623

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

521

624

if(ret != GNUTLS_E_SUCCESS){

522

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

523

safer_gnutls_strerror(ret));

625

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

626

safer_gnutls_strerror(ret));

524

627

gnutls_deinit(*session);

525

628

return -1;

526

629

}

528

631

/* ignore client certificate if any. */

529

632

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

530

633

531

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

634

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

532

635

533

636

return 0;

534

637

}

538

641

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

539

642

540

643

/* Called when a Mandos server is found */

541

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

644

__attribute__((nonnull, warn_unused_result))

645

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

542

646

AvahiIfIndex if_index,

543

int af){

647

int af, mandos_context *mc){

544

648

int ret, tcp_sd = -1;

545

649

ssize_t sret;

546

union {

547

struct sockaddr_in in;

548

struct sockaddr_in6 in6;

549

} to;

650

struct sockaddr_storage to;

550

651

char *buffer = NULL;

551

652

char *decrypted_buffer = NULL;

552

653

size_t buffer_length = 0;

571

672

pf = PF_INET;

572

673

break;

573

674

default:

574

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

675

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

575

676

errno = EINVAL;

576

677

return -1;

577

678

}

578

679

579

ret = init_gnutls_session(&session);

680

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

681

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

682

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

683

bool match = false;

684

{

685

char *interface = NULL;

686

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

687

interface))){

688

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

689

match = true;

690

break;

691

}

692

}

693

}

694

if(not match){

695

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

696

connect to the server */

697

if(debug){

698

char interface[IF_NAMESIZE];

699

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

700

perror_plus("if_indextoname");

701

} else {

702

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

703

" \"%s\"\n",

704

if_indextoname((unsigned int)if_index,

705

interface));

706

}

707

}

708

return -1;

709

}

710

}

711

712

ret = init_gnutls_session(&session, mc);

580

713

if(ret != 0){

581

714

return -1;

582

715

}

583

716

584

717

if(debug){

585

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

586

"\n", ip, port);

718

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

719

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

587

720

}

588

721

589

722

tcp_sd = socket(pf, SOCK_STREAM, 0);

590

723

if(tcp_sd < 0){

591

724

int e = errno;

592

perror("socket");

725

perror_plus("socket");

593

726

errno = e;

594

727

goto mandos_end;

595

728

}

601

734

602

735

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

603

736

if(af == AF_INET6){

604

to.in6.sin6_family = (sa_family_t)af;

605

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

737

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

738

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

606

739

} else { /* IPv4 */

607

to.in.sin_family = (sa_family_t)af;

608

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

740

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

741

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

609

742

}

610

743

if(ret < 0 ){

611

744

int e = errno;

612

perror("inet_pton");

745

perror_plus("inet_pton");

613

746

errno = e;

614

747

goto mandos_end;

615

748

}

616

749

if(ret == 0){

617

750

int e = errno;

618

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

751

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

619

752

errno = e;

620

753

goto mandos_end;

621

754

}

622

755

if(af == AF_INET6){

623

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

624

-Wconversion and

625

-Wunreachable-code */

626

627

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

628

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

629

-Wunreachable-code*/

756

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

757

if(IN6_IS_ADDR_LINKLOCAL

758

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

630

759

if(if_index == AVAHI_IF_UNSPEC){

631

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

632

" without a network interface\n");

760

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

761

" incomplete without a network interface\n");

633

762

errno = EINVAL;

634

763

goto mandos_end;

635

764

}

636

765

/* Set the network interface number as scope */

637

to.in6.sin6_scope_id = (uint32_t)if_index;

766

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

638

767

}

639

768

} else {

640

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

641

-Wconversion and

642

-Wunreachable-code */

769

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

643

770

}

644

771

645

772

if(quit_now){

651

778

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

652

779

char interface[IF_NAMESIZE];

653

780

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

654

perror("if_indextoname");

781

perror_plus("if_indextoname");

655

782

} else {

656

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

657

ip, interface, port);

783

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

784

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

658

785

}

659

786

} else {

660

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

661

port);

787

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

788

ip, (uintmax_t)port);

662

789

}

663

790

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

664

791

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

665

const char *pcret;

666

792

if(af == AF_INET6){

667

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

668

sizeof(addrstr));

793

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

794

sizeof(struct sockaddr_in6),

795

addrstr, sizeof(addrstr), NULL, 0,

796

NI_NUMERICHOST);

669

797

} else {

670

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

671

sizeof(addrstr));

798

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

799

sizeof(struct sockaddr_in),

800

addrstr, sizeof(addrstr), NULL, 0,

801

NI_NUMERICHOST);

672

802

}

673

if(pcret == NULL){

674

perror("inet_ntop");

675

} else {

676

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

677

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

678

}

803

if(ret == EAI_SYSTEM){

804

perror_plus("getnameinfo");

805

} else if(ret != 0) {

806

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

807

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

808

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

679

809

}

680

810

}

681

811

685

815

}

686

816

687

817

if(af == AF_INET6){

688

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

818

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

819

sizeof(struct sockaddr_in6));

689

820

} else {

690

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

821

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

822

sizeof(struct sockaddr_in));

691

823

}

692

824

if(ret < 0){

693

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

825

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

694

826

int e = errno;

695

perror("connect");

827

perror_plus("connect");

696

828

errno = e;

697

829

}

698

830

goto mandos_end;

708

840

while(true){

709

841

size_t out_size = strlen(out);

710

842

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

711

out_size - written));

843

out_size - written));

712

844

if(ret == -1){

713

845

int e = errno;

714

perror("write");

846

perror_plus("write");

715

847

errno = e;

716

848

goto mandos_end;

717

849

}

734

866

}

735

867

736

868

if(debug){

737

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

869

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

738

870

}

739

871

740

872

if(quit_now){

742

874

goto mandos_end;

743

875

}

744

876

745

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

877

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

878

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

879

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

880

gnutls_transport_set_ptr(session,

881

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

746

882

747

883

if(quit_now){

748

884

errno = EINTR;

759

895

760

896

if(ret != GNUTLS_E_SUCCESS){

761

897

if(debug){

762

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

898

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

763

899

gnutls_perror(ret);

764

900

}

765

901

errno = EPROTO;

769

905

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

770

906

771

907

if(debug){

772

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

773

ip);

908

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

909

" %s\n", ip);

774

910

}

775

911

776

912

while(true){

781

917

}

782

918

783

919

buffer_capacity = incbuffer(&buffer, buffer_length,

784

buffer_capacity);

920

buffer_capacity);

785

921

if(buffer_capacity == 0){

786

922

int e = errno;

787

perror("incbuffer");

923

perror_plus("incbuffer");

788

924

errno = e;

789

925

goto mandos_end;

790

926

}

814

950

}

815

951

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

816

952

if(ret < 0){

817

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

953

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

954

"***\n");

818

955

gnutls_perror(ret);

819

956

errno = EPROTO;

820

957

goto mandos_end;

821

958

}

822

959

break;

823

960

default:

824

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

825

" encrypted session with Mandos server\n");

961

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

962

" encrypted session with Mandos server\n");

826

963

gnutls_bye(session, GNUTLS_SHUT_RDWR);

827

964

errno = EIO;

828

965

goto mandos_end;

833

970

}

834

971

835

972

if(debug){

836

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

973

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

837

974

}

838

975

839

976

if(quit_now){

851

988

852

989

if(buffer_length > 0){

853

990

ssize_t decrypted_buffer_size;

854

decrypted_buffer_size = pgp_packet_decrypt(buffer,

855

buffer_length,

856

&decrypted_buffer);

991

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

992

&decrypted_buffer, mc);

857

993

if(decrypted_buffer_size >= 0){

858

994

859

995

written = 0;

869

1005

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

870

1006

int e = errno;

871

1007

if(debug){

872

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

873

strerror(errno));

1008

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

1009

strerror(errno));

874

1010

}

875

1011

errno = e;

876

1012

goto mandos_end;

895

1031

if(e == 0){

896

1032

e = errno;

897

1033

}

898

perror("close");

1034

perror_plus("close");

899

1035

}

900

1036

gnutls_deinit(session);

1037

errno = e;

901

1038

if(quit_now){

902

e = EINTR;

1039

errno = EINTR;

903

1040

retval = -1;

904

1041

}

905

errno = e;

906

1042

}

907

1043

return retval;

908

1044

}

909

1045

1046

__attribute__((nonnull))

910

1047

static void resolve_callback(AvahiSServiceResolver *r,

911

1048

AvahiIfIndex interface,

912

1049

AvahiProtocol proto,

920

1057

AVAHI_GCC_UNUSED AvahiStringList *txt,

921

1058

AVAHI_GCC_UNUSED AvahiLookupResultFlags

922

1059

flags,

923

AVAHI_GCC_UNUSED void* userdata){

924

assert(r);

1060

void *mc){

1061

if(r == NULL){

1062

return;

1063

}

925

1064

926

1065

/* Called whenever a service has been resolved successfully or

927

1066

timed out */

933

1072

switch(event){

934

1073

default:

935

1074

case AVAHI_RESOLVER_FAILURE:

936

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

937

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

938

avahi_strerror(avahi_server_errno(mc.server)));

1075

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

1076

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

1077

domain,

1078

avahi_strerror(avahi_server_errno

1079

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

939

1080

break;

940

1081

941

1082

case AVAHI_RESOLVER_FOUND:

943

1084

char ip[AVAHI_ADDRESS_STR_MAX];

944

1085

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

945

1086

if(debug){

946

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

947

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

948

ip, (intmax_t)interface, port);

1087

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

1088

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

1089

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

949

1090

}

950

int ret = start_mandos_communication(ip, port, interface,

951

avahi_proto_to_af(proto));

1091

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

1092

interface,

1093

avahi_proto_to_af(proto),

1094

mc);

952

1095

if(ret == 0){

953

avahi_simple_poll_quit(mc.simple_poll);

1096

avahi_simple_poll_quit(simple_poll);

1097

} else {

1098

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

1099

avahi_proto_to_af(proto),

1100

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

1101

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

1102

" list\n", name);

1103

}

954

1104

}

955

1105

}

956

1106

}

966

1116

const char *domain,

967

1117

AVAHI_GCC_UNUSED AvahiLookupResultFlags

968

1118

flags,

969

AVAHI_GCC_UNUSED void* userdata){

970

assert(b);

1119

void *mc){

1120

if(b == NULL){

1121

return;

1122

}

971

1123

972

1124

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

973

1125

is removed from the LAN */

980

1132

default:

981

1133

case AVAHI_BROWSER_FAILURE:

982

1134

983

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

984

avahi_strerror(avahi_server_errno(mc.server)));

985

avahi_simple_poll_quit(mc.simple_poll);

1135

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

1136

avahi_strerror(avahi_server_errno

1137

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

1138

avahi_simple_poll_quit(simple_poll);

986

1139

return;

987

1140

988

1141

case AVAHI_BROWSER_NEW:

991

1144

the callback function is called the Avahi server will free the

992

1145

resolver for us. */

993

1146

994

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

995

name, type, domain, protocol, 0,

996

resolve_callback, NULL) == NULL)

997

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

998

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

1147

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

1148

interface, protocol, name, type,

1149

domain, protocol, 0,

1150

resolve_callback, mc) == NULL)

1151

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

1152

" %s\n", name,

1153

avahi_strerror(avahi_server_errno

1154

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

999

1155

break;

1000

1156

1001

1157

case AVAHI_BROWSER_REMOVE:

1004

1160

case AVAHI_BROWSER_ALL_FOR_NOW:

1005

1161

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1006

1162

if(debug){

1007

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

1163

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

1164

" searching...\n");

1008

1165

}

1009

1166

break;

1010

1167

}

1011

1168

}

1012

1169

1013

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

1170

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

1014

1171

static void handle_sigterm(int sig){

1015

1172

if(quit_now){

1016

1173

return;

1018

1175

quit_now = 1;

1019

1176

signal_received = sig;

1020

1177

int old_errno = errno;

1021

if(mc.simple_poll != NULL){

1022

avahi_simple_poll_quit(mc.simple_poll);

1178

/* set main loop to exit */

1179

if(simple_poll != NULL){

1180

avahi_simple_poll_quit(simple_poll);

1023

1181

}

1024

1182

errno = old_errno;

1025

1183

}

1026

1184

1185

__attribute__((nonnull, warn_unused_result))

1186

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

1187

int ret;

1188

error_t ret_errno;

1189

1190

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

1191

if(s < 0){

1192

ret_errno = errno;

1193

perror_plus("socket");

1194

errno = ret_errno;

1195

return false;

1196

}

1197

strcpy(ifr->ifr_name, ifname);

1198

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1199

if(ret == -1){

1200

if(debug){

1201

ret_errno = errno;

1202

perror_plus("ioctl SIOCGIFFLAGS");

1203

errno = ret_errno;

1204

}

1205

return false;

1206

}

1207

return true;

1208

}

1209

1210

__attribute__((nonnull, warn_unused_result))

1211

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

1212

1213

/* Reject the loopback device */

1214

if(ifr->ifr_flags & IFF_LOOPBACK){

1215

if(debug){

1216

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

1217

ifname);

1218

}

1219

return false;

1220

}

1221

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

1222

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

1223

if(debug){

1224

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

1225

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

1226

}

1227

return true;

1228

}

1229

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

1230

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

1231

if(debug){

1232

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1233

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

1234

}

1235

return false;

1236

}

1237

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

1238

if(ifr->ifr_flags & IFF_NOARP){

1239

if(debug){

1240

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

1241

ifname);

1242

}

1243

return false;

1244

}

1245

1246

/* Accept this device */

1247

if(debug){

1248

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

1249

}

1250

return true;

1251

}

1252

1027

1253

/*

1028

1254

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

1029

1255

* corresponds to an acceptable network device.

1030

1256

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

1031

1257

*/

1258

__attribute__((nonnull, warn_unused_result))

1032

1259

int good_interface(const struct dirent *if_entry){

1033

ssize_t ssret;

1034

char *flagname = NULL;

1035

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

1036

if_entry->d_name);

1037

if(ret < 0){

1038

perror("asprintf");

1039

return 0;

1040

}

1041

1260

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

1042

1261

return 0;

1043

1262

}

1044

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

1045

if(flags_fd == -1){

1046

perror("open");

1047

return 0;

1048

}

1049

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

1050

/* read line from flags_fd */

1051

ssize_t to_read = (sizeof(ifreq_flags)*2)+3; /* "0x1003\n" */

1052

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

1053

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

1054

if(flagstring == NULL){

1055

perror("malloc");

1056

close(flags_fd);

1057

return 0;

1058

}

1059

while(to_read > 0){

1060

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

1061

(size_t)to_read));

1062

if(ssret == -1){

1063

perror("read");

1064

free(flagstring);

1065

close(flags_fd);

1066

return 0;

1067

}

1068

to_read -= ssret;

1069

if(ssret == 0){

1263

1264

struct ifreq ifr;

1265

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

1266

if(debug){

1267

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

1268

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

1269

}

1270

return 0;

1271

}

1272

1273

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

1274

return 0;

1275

}

1276

return 1;

1277

}

1278

1279

/*

1280

* This function determines if a network interface is up.

1281

*/

1282

__attribute__((nonnull, warn_unused_result))

1283

bool interface_is_up(const char *interface){

1284

struct ifreq ifr;

1285

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

1286

if(debug){

1287

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

1288

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

1289

}

1290

return false;

1291

}

1292

1293

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

1294

}

1295

1296

/*

1297

* This function determines if a network interface is running

1298

*/

1299

__attribute__((nonnull, warn_unused_result))

1300

bool interface_is_running(const char *interface){

1301

struct ifreq ifr;

1302

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

1303

if(debug){

1304

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

1305

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

1306

}

1307

return false;

1308

}

1309

1310

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

1311

}

1312

1313

__attribute__((nonnull, pure, warn_unused_result))

1314

int notdotentries(const struct dirent *direntry){

1315

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

1316

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

1317

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

1318

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

1319

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

1320

return 0;

1321

}

1322

return 1;

1323

}

1324

1325

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

1326

__attribute__((nonnull, warn_unused_result))

1327

int runnable_hook(const struct dirent *direntry){

1328

int ret;

1329

size_t sret;

1330

struct stat st;

1331

1332

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

1333

/* Empty name? */

1334

return 0;

1335

}

1336

1337

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

1338

"abcdefghijklmnopqrstuvwxyz"

1339

"0123456789"

1340

"_.-");

1341

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

1342

/* Contains non-allowed characters */

1343

if(debug){

1344

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

1345

direntry->d_name);

1346

}

1347

return 0;

1348

}

1349

1350

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

1351

if(ret == -1){

1352

if(debug){

1353

perror_plus("Could not stat hook");

1354

}

1355

return 0;

1356

}

1357

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

1358

/* Not a regular file */

1359

if(debug){

1360

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

1361

direntry->d_name);

1362

}

1363

return 0;

1364

}

1365

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

1366

/* Not executable */

1367

if(debug){

1368

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

1369

direntry->d_name);

1370

}

1371

return 0;

1372

}

1373

if(debug){

1374

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

1375

direntry->d_name);

1376

}

1377

return 1;

1378

}

1379

1380

__attribute__((nonnull, warn_unused_result))

1381

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1382

mandos_context *mc){

1383

int ret;

1384

struct timespec now;

1385

struct timespec waited_time;

1386

intmax_t block_time;

1387

1388

while(true){

1389

if(mc->current_server == NULL){

1390

if(debug){

1391

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

1392

" No timeout!\n");

1393

}

1394

ret = avahi_simple_poll_iterate(s, -1);

1395

} else {

1396

if(debug){

1397

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

1398

" it, or wait\n");

1399

}

1400

/* the current time */

1401

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1402

if(ret == -1){

1403

perror_plus("clock_gettime");

1404

return -1;

1405

}

1406

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

1407

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

1408

waited_time.tv_sec = (now.tv_sec

1409

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

1410

waited_time.tv_nsec = (now.tv_nsec

1411

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

1412

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

1413

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

1414

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

1415

block_time = ((retry_interval

1416

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

1417

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

1418

1419

if(debug){

1420

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

1421

block_time);

1422

}

1423

1424

if(block_time <= 0){

1425

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

1426

mc->current_server->port,

1427

mc->current_server->if_index,

1428

mc->current_server->af, mc);

1429

if(ret == 0){

1430

avahi_simple_poll_quit(s);

1431

return 0;

1432

}

1433

ret = clock_gettime(CLOCK_MONOTONIC,

1434

&mc->current_server->last_seen);

1435

if(ret == -1){

1436

perror_plus("clock_gettime");

1437

return -1;

1438

}

1439

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

1440

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

1441

servers, but don't block */

1442

}

1443

1444

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

1445

}

1446

if(ret != 0){

1447

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

1448

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

1449

}

1450

}

1451

}

1452

}

1453

1454

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

1455

__attribute__((warn_unused_result))

1456

error_t raise_privileges(void){

1457

error_t old_errno = errno;

1458

error_t ret_errno = 0;

1459

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

1460

ret_errno = errno;

1461

perror_plus("seteuid");

1462

}

1463

errno = old_errno;

1464

return ret_errno;

1465

}

1466

1467

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

1468

__attribute__((warn_unused_result))

1469

error_t raise_privileges_permanently(void){

1470

error_t old_errno = errno;

1471

error_t ret_errno = raise_privileges();

1472

if(ret_errno != 0){

1473

errno = old_errno;

1474

return ret_errno;

1475

}

1476

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

1477

ret_errno = errno;

1478

perror_plus("seteuid");

1479

}

1480

errno = old_errno;

1481

return ret_errno;

1482

}

1483

1484

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

1485

__attribute__((warn_unused_result))

1486

error_t lower_privileges(void){

1487

error_t old_errno = errno;

1488

error_t ret_errno = 0;

1489

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

1490

ret_errno = errno;

1491

perror_plus("seteuid");

1492

}

1493

errno = old_errno;

1494

return ret_errno;

1495

}

1496

1497

/* Lower privileges permanently */

1498

__attribute__((warn_unused_result))

1499

error_t lower_privileges_permanently(void){

1500

error_t old_errno = errno;

1501

error_t ret_errno = 0;

1502

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

1503

ret_errno = errno;

1504

perror_plus("setuid");

1505

}

1506

errno = old_errno;

1507

return ret_errno;

1508

}

1509

1510

__attribute__((nonnull))

1511

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

1512

const float delay){

1513

struct dirent **direntries;

1514

if(hookdir_fd == -1){

1515

hookdir_fd = open(hookdir, O_RDONLY);

1516

if(hookdir_fd == -1){

1517

if(errno == ENOENT){

1518

if(debug){

1519

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

1520

" found\n", hookdir);

1521

}

1522

} else {

1523

perror_plus("open");

1524

}

1525

return;

1526

}

1527

}

1528

#ifdef __GLIBC__

1529

#if __GLIBC_PREREQ(2, 15)

1530

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

1531

runnable_hook, alphasort);

1532

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

1533

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

1534

alphasort);

1535

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

1536

#else /* not __GLIBC__ */

1537

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

1538

alphasort);

1539

#endif /* not __GLIBC__ */

1540

if(numhooks == -1){

1541

perror_plus("scandir");

1542

return;

1543

}

1544

struct dirent *direntry;

1545

int ret;

1546

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

1547

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

1548

direntry = direntries[i];

1549

if(debug){

1550

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

1551

direntry->d_name);

1552

}

1553

pid_t hook_pid = fork();

1554

if(hook_pid == 0){

1555

/* Child */

1556

/* Raise privileges */

1557

if(raise_privileges_permanently() != 0){

1558

perror_plus("Failed to raise privileges");

1559

_exit(EX_NOPERM);

1560

}

1561

/* Set group */

1562

errno = 0;

1563

ret = setgid(0);

1564

if(ret == -1){

1565

perror_plus("setgid");

1566

_exit(EX_NOPERM);

1567

}

1568

/* Reset supplementary groups */

1569

errno = 0;

1570

ret = setgroups(0, NULL);

1571

if(ret == -1){

1572

perror_plus("setgroups");

1573

_exit(EX_NOPERM);

1574

}

1575

ret = dup2(devnull, STDIN_FILENO);

1576

if(ret == -1){

1577

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

1578

_exit(EX_OSERR);

1579

}

1580

ret = close(devnull);

1581

if(ret == -1){

1582

perror_plus("close");

1583

_exit(EX_OSERR);

1584

}

1585

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1586

if(ret == -1){

1587

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

1588

_exit(EX_OSERR);

1589

}

1590

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

1591

if(ret == -1){

1592

perror_plus("setenv");

1593

_exit(EX_OSERR);

1594

}

1595

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

1596

if(ret == -1){

1597

perror_plus("setenv");

1598

_exit(EX_OSERR);

1599

}

1600

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

1601

if(ret == -1){

1602

perror_plus("setenv");

1603

_exit(EX_OSERR);

1604

}

1605

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

1606

if(ret == -1){

1607

perror_plus("setenv");

1608

_exit(EX_OSERR);

1609

}

1610

char *delaystring;

1611

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

1612

if(ret == -1){

1613

perror_plus("asprintf");

1614

_exit(EX_OSERR);

1615

}

1616

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

1617

if(ret == -1){

1618

free(delaystring);

1619

perror_plus("setenv");

1620

_exit(EX_OSERR);

1621

}

1622

free(delaystring);

1623

if(connect_to != NULL){

1624

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

1625

if(ret == -1){

1626

perror_plus("setenv");

1627

_exit(EX_OSERR);

1628

}

1629

}

1630

int hook_fd = openat(hookdir_fd, direntry->d_name, O_RDONLY);

1631

if(hook_fd == -1){

1632

perror_plus("openat");

1633

_exit(EXIT_FAILURE);

1634

}

1635

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

1636

perror_plus("close");

1637

_exit(EXIT_FAILURE);

1638

}

1639

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

1640

environ) == -1){

1641

perror_plus("fexecve");

1642

_exit(EXIT_FAILURE);

1643

}

1644

} else {

1645

int status;

1646

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

1647

perror_plus("waitpid");

1648

continue;

1649

}

1650

if(WIFEXITED(status)){

1651

if(WEXITSTATUS(status) != 0){

1652

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

1653

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

1654

WEXITSTATUS(status));

1655

continue;

1656

}

1657

} else if(WIFSIGNALED(status)){

1658

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

1659

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

1660

WTERMSIG(status));

1661

continue;

1662

} else {

1663

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

1664

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

1665

continue;

1666

}

1667

}

1668

if(debug){

1669

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

1670

direntry->d_name);

1671

}

1672

}

1673

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

1674

perror_plus("close");

1675

} else {

1676

hookdir_fd = -1;

1677

}

1678

close(devnull);

1679

}

1680

1681

__attribute__((nonnull, warn_unused_result))

1682

error_t bring_up_interface(const char *const interface,

1683

const float delay){

1684

error_t old_errno = errno;

1685

int ret;

1686

struct ifreq network;

1687

unsigned int if_index = if_nametoindex(interface);

1688

if(if_index == 0){

1689

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

1690

errno = old_errno;

1691

return ENXIO;

1692

}

1693

1694

if(quit_now){

1695

errno = old_errno;

1696

return EINTR;

1697

}

1698

1699

if(not interface_is_up(interface)){

1700

error_t ret_errno = 0, ioctl_errno = 0;

1701

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

1702

ret_errno = errno;

1703

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

1704

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

1705

errno = old_errno;

1706

return ret_errno;

1707

}

1708

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

1709

1710

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

1711

if(sd == -1){

1712

ret_errno = errno;

1713

perror_plus("socket");

1714

errno = old_errno;

1715

return ret_errno;

1716

}

1717

1718

if(quit_now){

1719

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

1720

if(ret == -1){

1721

perror_plus("close");

1722

}

1723

errno = old_errno;

1724

return EINTR;

1725

}

1726

1727

if(debug){

1728

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

1729

interface);

1730

}

1731

1732

/* Raise privileges */

1733

ret_errno = raise_privileges();

1734

if(ret_errno != 0){

1735

perror_plus("Failed to raise privileges");

1736

}

1737

1738

#ifdef __linux__

1739

int ret_linux;

1740

bool restore_loglevel = false;

1741

if(ret_errno == 0){

1742

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1743

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

1744

ret_linux = klogctl(8, NULL, 5);

1745

if(ret_linux == -1){

1746

perror_plus("klogctl");

1747

} else {

1748

restore_loglevel = true;

1749

}

1750

}

1751

#endif /* __linux__ */

1752

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

1753

ioctl_errno = errno;

1754

#ifdef __linux__

1755

if(restore_loglevel){

1756

ret_linux = klogctl(7, NULL, 0);

1757

if(ret_linux == -1){

1758

perror_plus("klogctl");

1759

}

1760

}

1761

#endif /* __linux__ */

1762

1763

/* If raise_privileges() succeeded above */

1764

if(ret_errno == 0){

1765

/* Lower privileges */

1766

ret_errno = lower_privileges();

1767

if(ret_errno != 0){

1768

errno = ret_errno;

1769

perror_plus("Failed to lower privileges");

1770

}

1771

}

1772

1773

/* Close the socket */

1774

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

1775

if(ret == -1){

1776

perror_plus("close");

1777

}

1778

1779

if(ret_setflags == -1){

1780

errno = ioctl_errno;

1781

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1782

errno = old_errno;

1783

return ioctl_errno;

1784

}

1785

} else if(debug){

1786

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

1787

interface);

1788

}

1789

1790

/* Sleep checking until interface is running.

1791

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

1792

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

1793

if(interface_is_running(interface)){

1070

1794

break;

1071

1795

}

1072

}

1073

close(flags_fd);

1074

intmax_t tmpmax;

1075

char *tmp;

1076

errno = 0;

1077

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

1078

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

1079

and not (isspace(*tmp)))

1080

or tmpmax != (ifreq_flags)tmpmax){

1081

if(debug){

1082

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

1083

flagstring, if_entry->d_name);

1084

}

1085

free(flagstring);

1086

return 0;

1087

}

1088

free(flagstring);

1089

ifreq_flags flags = (ifreq_flags)tmpmax;

1090

/* Reject the loopback device */

1091

if(flags & IFF_LOOPBACK){

1092

if(debug){

1093

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

1094

if_entry->d_name);

1095

}

1096

return 0;

1097

}

1098

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

1099

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

1100

if(debug){

1101

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

1102

if_entry->d_name);

1103

}

1104

return 1;

1105

}

1106

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

1107

if(not (flags & IFF_BROADCAST)){

1108

if(debug){

1109

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

1110

if_entry->d_name);

1111

}

1112

return 0;

1113

}

1114

/* Accept this device */

1115

if(debug){

1116

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

1117

if_entry->d_name);

1118

}

1119

return 1;

1796

struct timespec sleeptime = { .tv_nsec = 250000000 };

1797

ret = nanosleep(&sleeptime, NULL);

1798

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

1799

perror_plus("nanosleep");

1800

}

1801

}

1802

1803

errno = old_errno;

1804

return 0;

1805

}

1806

1807

__attribute__((nonnull, warn_unused_result))

1808

error_t take_down_interface(const char *const interface){

1809

error_t old_errno = errno;

1810

struct ifreq network;

1811

unsigned int if_index = if_nametoindex(interface);

1812

if(if_index == 0){

1813

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

1814

errno = old_errno;

1815

return ENXIO;

1816

}

1817

if(interface_is_up(interface)){

1818

error_t ret_errno = 0, ioctl_errno = 0;

1819

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

1820

ret_errno = errno;

1821

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

1822

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

1823

errno = old_errno;

1824

return ret_errno;

1825

}

1826

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

1827

1828

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

1829

if(sd == -1){

1830

ret_errno = errno;

1831

perror_plus("socket");

1832

errno = old_errno;

1833

return ret_errno;

1834

}

1835

1836

if(debug){

1837

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

1838

interface);

1839

}

1840

1841

/* Raise privileges */

1842

ret_errno = raise_privileges();

1843

if(ret_errno != 0){

1844

perror_plus("Failed to raise privileges");

1845

}

1846

1847

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

1848

ioctl_errno = errno;

1849

1850

/* If raise_privileges() succeeded above */

1851

if(ret_errno == 0){

1852

/* Lower privileges */

1853

ret_errno = lower_privileges();

1854

if(ret_errno != 0){

1855

errno = ret_errno;

1856

perror_plus("Failed to lower privileges");

1857

}

1858

}

1859

1860

/* Close the socket */

1861

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

1862

if(ret == -1){

1863

perror_plus("close");

1864

}

1865

1866

if(ret_setflags == -1){

1867

errno = ioctl_errno;

1868

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1869

errno = old_errno;

1870

return ioctl_errno;

1871

}

1872

} else if(debug){

1873

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

1874

interface);

1875

}

1876

1877

errno = old_errno;

1878

return 0;

1120

1879

}

1121

1880

1122

1881

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

1882

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

1883

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

1884

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

1885

.interfaces = NULL, .interfaces_size = 0 };

1123

1886

AvahiSServiceBrowser *sb = NULL;

1124

int error;

1887

error_t ret_errno;

1125

1888

int ret;

1126

1889

intmax_t tmpmax;

1127

1890

char *tmp;

1128

1891

int exitcode = EXIT_SUCCESS;

1129

const char *interface = "";

1130

struct ifreq network;

1131

int sd = -1;

1132

bool take_down_interface = false;

1133

uid_t uid;

1134

gid_t gid;

1135

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

1136

bool tempdir_created = false;

1892

char *interfaces_to_take_down = NULL;

1893

size_t interfaces_to_take_down_size = 0;

1894

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

1895

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

1896

char *tempdir = NULL;

1137

1897

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1138

1898

const char *seckey = PATHDIR "/" SECKEY;

1139

1899

const char *pubkey = PATHDIR "/" PUBKEY;

1900

char *interfaces_hooks = NULL;

1140

1901

1141

1902

bool gnutls_initialized = false;

1142

1903

bool gpgme_initialized = false;

1143

1904

float delay = 2.5f;

1905

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

1906

retrying the same server again */

1144

1907

1145

1908

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1146

1909

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1152

1915

errno = 0;

1153

1916

ret = setgid(gid);

1154

1917

if(ret == -1){

1155

perror("setgid");

1918

perror_plus("setgid");

1156

1919

}

1157

1920

1158

1921

/* Lower user privileges (temporarily) */

1159

1922

errno = 0;

1160

1923

ret = seteuid(uid);

1161

1924

if(ret == -1){

1162

perror("seteuid");

1925

perror_plus("seteuid");

1163

1926

}

1164

1927

1165

1928

if(quit_now){

1200

1963

.arg = "SECONDS",

1201

1964

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

1202

1965

.group = 2 },

1966

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

1967

.arg = "SECONDS",

1968

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

1969

.group = 2 },

1970

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

1971

.arg = "DIR",

1972

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

1973

.group = 2 },

1203

1974

/*

1204

1975

* These reproduce what we would get without ARGP_NO_HELP

1205

1976

*/

1223

1994

connect_to = arg;

1224

1995

break;

1225

1996

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

1226

interface = arg;

1997

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

1998

arg, (int)',');

1999

if(ret_errno != 0){

2000

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

2001

}

1227

2002

break;

1228

2003

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

1229

2004

seckey = arg;

1249

2024

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

1250

2025

argp_error(state, "Bad delay");

1251

2026

}

2027

case 132: /* --retry */

2028

errno = 0;

2029

retry_interval = strtod(arg, &tmp);

2030

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

2031

or (retry_interval * 1000) > INT_MAX

2032

or retry_interval < 0){

2033

argp_error(state, "Bad retry interval");

2034

}

2035

break;

2036

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

2037

hookdir = arg;

1252

2038

break;

1253

2039

/*

1254

2040

* These reproduce what we would get without ARGP_NO_HELP

1261

2047

argp_state_help(state, state->out_stream,

1262

2048

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1263

2049

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

1264

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

2050

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

1265

2051

exit(argp_err_exit_status);

1266

2052

break;

1267

2053

default:

1282

2068

case ENOMEM:

1283

2069

default:

1284

2070

errno = ret;

1285

perror("argp_parse");

2071

perror_plus("argp_parse");

1286

2072

exitcode = EX_OSERR;

1287

2073

goto end;

1288

2074

case EINVAL:

1290

2076

goto end;

1291

2077

}

1292

2078

}

2079

2080

{

2081

/* Work around Debian bug #633582:

2082

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

2083

2084

/* Re-raise privileges */

2085

ret_errno = raise_privileges();

2086

if(ret_errno != 0){

2087

errno = ret_errno;

2088

perror_plus("Failed to raise privileges");

2089

} else {

2090

struct stat st;

2091

2092

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

2093

int seckey_fd = open(seckey, O_RDONLY);

2094

if(seckey_fd == -1){

2095

perror_plus("open");

2096

} else {

2097

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

2098

if(ret == -1){

2099

perror_plus("fstat");

2100

} else {

2101

if(S_ISREG(st.st_mode)

2102

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

2103

ret = fchown(seckey_fd, uid, gid);

2104

if(ret == -1){

2105

perror_plus("fchown");

2106

}

2107

}

2108

}

2109

TEMP_FAILURE_RETRY(close(seckey_fd));

2110

}

2111

}

2112

2113

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

2114

int pubkey_fd = open(pubkey, O_RDONLY);

2115

if(pubkey_fd == -1){

2116

perror_plus("open");

2117

} else {

2118

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

2119

if(ret == -1){

2120

perror_plus("fstat");

2121

} else {

2122

if(S_ISREG(st.st_mode)

2123

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

2124

ret = fchown(pubkey_fd, uid, gid);

2125

if(ret == -1){

2126

perror_plus("fchown");

2127

}

2128

}

2129

}

2130

TEMP_FAILURE_RETRY(close(pubkey_fd));

2131

}

2132

}

2133

2134

/* Lower privileges */

2135

ret_errno = lower_privileges();

2136

if(ret_errno != 0){

2137

errno = ret_errno;

2138

perror_plus("Failed to lower privileges");

2139

}

2140

}

2141

}

2142

2143

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

2144

{

2145

char *interface = NULL;

2146

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

2147

interface))){

2148

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

2149

and if_nametoindex(interface) == 0){

2150

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

2151

fprintf_plus(stderr, "Not using nonexisting interface"

2152

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

2153

}

2154

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

2155

interface = NULL;

2156

}

2157

}

2158

}

2159

2160

/* Run network hooks */

2161

{

2162

if(mc.interfaces != NULL){

2163

interfaces_hooks = malloc(mc.interfaces_size);

2164

if(interfaces_hooks == NULL){

2165

perror_plus("malloc");

2166

goto end;

2167

}

2168

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

2169

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

2170

}

2171

run_network_hooks("start", interfaces_hooks != NULL ?

2172

interfaces_hooks : "", delay);

2173

}

1293

2174

1294

2175

if(not debug){

1295

2176

avahi_set_log_function(empty_log);

1296

2177

}

1297

1298

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

1299

struct dirent **direntries;

1300

ret = scandir(sys_class_net, &direntries, good_interface,

1301

alphasort);

1302

if(ret >= 1){

1303

/* Pick the first good interface */

1304

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

1305

if(debug){

1306

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

1307

}

1308

if(interface == NULL){

1309

perror("malloc");

1310

free(direntries);

1311

exitcode = EXIT_FAILURE;

1312

goto end;

1313

}

1314

free(direntries);

1315

} else {

1316

free(direntries);

1317

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

1318

exitcode = EXIT_FAILURE;

1319

goto end;

1320

}

1321

}

1322

2178

1323

2179

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

1324

2180

from the signal handler */

1325

2181

/* Initialize the pseudo-RNG for Avahi */

1326

2182

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

1327

mc.simple_poll = avahi_simple_poll_new();

1328

if(mc.simple_poll == NULL){

1329

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

2183

simple_poll = avahi_simple_poll_new();

2184

if(simple_poll == NULL){

2185

fprintf_plus(stderr,

2186

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

1330

2187

exitcode = EX_UNAVAILABLE;

1331

2188

goto end;

1332

2189

}

1334

2191

sigemptyset(&sigterm_action.sa_mask);

1335

2192

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

1336

2193

if(ret == -1){

1337

perror("sigaddset");

2194

perror_plus("sigaddset");

1338

2195

exitcode = EX_OSERR;

1339

2196

goto end;

1340

2197

}

1341

2198

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

1342

2199

if(ret == -1){

1343

perror("sigaddset");

2200

perror_plus("sigaddset");

1344

2201

exitcode = EX_OSERR;

1345

2202

goto end;

1346

2203

}

1347

2204

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

1348

2205

if(ret == -1){

1349

perror("sigaddset");

2206

perror_plus("sigaddset");

1350

2207

exitcode = EX_OSERR;

1351

2208

goto end;

1352

2209

}

1356

2213

*/

1357

2214

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

1358

2215

if(ret == -1){

1359

perror("sigaction");

2216

perror_plus("sigaction");

1360

2217

return EX_OSERR;

1361

2218

}

1362

2219

if(old_sigterm_action.sa_handler != SIG_IGN){

1363

2220

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

1364

2221

if(ret == -1){

1365

perror("sigaction");

2222

perror_plus("sigaction");

1366

2223

exitcode = EX_OSERR;

1367

2224

goto end;

1368

2225

}

1369

2226

}

1370

2227

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

1371

2228

if(ret == -1){

1372

perror("sigaction");

2229

perror_plus("sigaction");

1373

2230

return EX_OSERR;

1374

2231

}

1375

2232

if(old_sigterm_action.sa_handler != SIG_IGN){

1376

2233

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

1377

2234

if(ret == -1){

1378

perror("sigaction");

2235

perror_plus("sigaction");

1379

2236

exitcode = EX_OSERR;

1380

2237

goto end;

1381

2238

}

1382

2239

}

1383

2240

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

1384

2241

if(ret == -1){

1385

perror("sigaction");

2242

perror_plus("sigaction");

1386

2243

return EX_OSERR;

1387

2244

}

1388

2245

if(old_sigterm_action.sa_handler != SIG_IGN){

1389

2246

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

1390

2247

if(ret == -1){

1391

perror("sigaction");

1392

exitcode = EX_OSERR;

1393

goto end;

1394

}

1395

}

1396

1397

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

1398

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

1399

if_index = (AvahiIfIndex) if_nametoindex(interface);

1400

if(if_index == 0){

1401

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

1402

exitcode = EX_UNAVAILABLE;

1403

goto end;

1404

}

1405

1406

if(quit_now){

1407

goto end;

1408

}

1409

1410

/* Re-raise priviliges */

1411

errno = 0;

1412

ret = seteuid(0);

1413

if(ret == -1){

1414

perror("seteuid");

1415

}

1416

1417

#ifdef __linux__

1418

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1419

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

1420

ret = klogctl(8, NULL, 5);

1421

bool restore_loglevel = true;

1422

if(ret == -1){

1423

restore_loglevel = false;

1424

perror("klogctl");

1425

}

1426

#endif /* __linux__ */

1427

1428

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1429

if(sd < 0){

1430

perror("socket");

1431

exitcode = EX_OSERR;

1432

#ifdef __linux__

1433

if(restore_loglevel){

1434

ret = klogctl(7, NULL, 0);

1435

if(ret == -1){

1436

perror("klogctl");

1437

}

1438

}

1439

#endif /* __linux__ */

1440

/* Lower privileges */

1441

errno = 0;

1442

ret = seteuid(uid);

1443

if(ret == -1){

1444

perror("seteuid");

1445

}

1446

goto end;

1447

}

1448

strcpy(network.ifr_name, interface);

1449

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

1450

if(ret == -1){

1451

perror("ioctl SIOCGIFFLAGS");

1452

#ifdef __linux__

1453

if(restore_loglevel){

1454

ret = klogctl(7, NULL, 0);

1455

if(ret == -1){

1456

perror("klogctl");

1457

}

1458

}

1459

#endif /* __linux__ */

1460

exitcode = EX_OSERR;

1461

/* Lower privileges */

1462

errno = 0;

1463

ret = seteuid(uid);

1464

if(ret == -1){

1465

perror("seteuid");

1466

}

1467

goto end;

1468

}

1469

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

1470

network.ifr_flags |= IFF_UP;

1471

take_down_interface = true;

1472

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

1473

if(ret == -1){

1474

take_down_interface = false;

1475

perror("ioctl SIOCSIFFLAGS +IFF_UP");

1476

exitcode = EX_OSERR;

1477

#ifdef __linux__

1478

if(restore_loglevel){

1479

ret = klogctl(7, NULL, 0);

1480

if(ret == -1){

1481

perror("klogctl");

2248

perror_plus("sigaction");

2249

exitcode = EX_OSERR;

2250

goto end;

2251

}

2252

}

2253

2254

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

2255

if(mc.interfaces == NULL){

2256

struct dirent **direntries;

2257

/* Look for any good interfaces */

2258

ret = scandir(sys_class_net, &direntries, good_interface,

2259

alphasort);

2260

if(ret >= 1){

2261

/* Add all found interfaces to interfaces list */

2262

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

2263

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

2264

direntries[i]->d_name);

2265

if(ret_errno != 0){

2266

errno = ret_errno;

2267

perror_plus("argz_add");

2268

continue;

2269

}

2270

if(debug){

2271

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

2272

direntries[i]->d_name);

2273

}

2274

}

2275

free(direntries);

2276

} else {

2277

free(direntries);

2278

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

2279

exitcode = EXIT_FAILURE;

2280

goto end;

2281

}

2282

}

2283

2284

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

2285

{

2286

char *interface = NULL;

2287

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

2288

interface))){

2289

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

2290

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

2291

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

2292

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

2293

interface);

2294

interface = NULL;

2295

while((interface = argz_next(mc.interfaces,

2296

mc.interfaces_size, interface))){

2297

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

2298

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

2299

interface);

2300

interface = NULL;

1482

2301

}

1483

2302

}

1484

#endif /* __linux__ */

1485

/* Lower privileges */

1486

errno = 0;

1487

ret = seteuid(uid);

1488

if(ret == -1){

1489

perror("seteuid");

1490

}

1491

goto end;

1492

}

1493

}

1494

/* sleep checking until interface is running */

1495

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

1496

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

1497

if(ret == -1){

1498

perror("ioctl SIOCGIFFLAGS");

1499

} else if(network.ifr_flags & IFF_RUNNING){

1500

2303

break;

1501

2304

}

1502

struct timespec sleeptime = { .tv_nsec = 250000000 };

1503

ret = nanosleep(&sleeptime, NULL);

1504

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

1505

perror("nanosleep");

1506

}

1507

}

1508

if(not take_down_interface){

1509

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

1510

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

1511

if(ret == -1){

1512

perror("close");

1513

}

1514

}

1515

#ifdef __linux__

1516

if(restore_loglevel){

1517

/* Restores kernel loglevel to default */

1518

ret = klogctl(7, NULL, 0);

1519

if(ret == -1){

1520

perror("klogctl");

1521

}

1522

}

1523

#endif /* __linux__ */

1524

/* Lower privileges */

1525

errno = 0;

1526

if(take_down_interface){

1527

/* Lower privileges */

1528

ret = seteuid(uid);

1529

if(ret == -1){

1530

perror("seteuid");

1531

}

1532

} else {

1533

/* Lower privileges permanently */

1534

ret = setuid(uid);

1535

if(ret == -1){

1536

perror("setuid");

1537

}

1538

}

2305

bool interface_was_up = interface_is_up(interface);

2306

errno = bring_up_interface(interface, delay);

2307

if(not interface_was_up){

2308

if(errno != 0){

2309

perror_plus("Failed to bring up interface");

2310

} else {

2311

errno = argz_add(&interfaces_to_take_down,

2312

&interfaces_to_take_down_size,

2313

interface);

2314

if(errno != 0){

2315

perror_plus("argz_add");

2316

}

2317

}

2318

}

2319

}

2320

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

2321

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

2322

}

2323

}

2324

2325

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

2326

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

2327

if(debug){

2328

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

2329

mc.interfaces);

2330

}

2331

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

1539

2332

}

1540

2333

1541

2334

if(quit_now){

1542

2335

goto end;

1543

2336

}

1544

2337

1545

ret = init_gnutls_global(pubkey, seckey);

2338

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

1546

2339

if(ret == -1){

1547

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

2340

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

1548

2341

exitcode = EX_UNAVAILABLE;

1549

2342

goto end;

1550

2343

} else {

1555

2348

goto end;

1556

2349

}

1557

2350

1558

tempdir_created = true;

1559

if(mkdtemp(tempdir) == NULL){

1560

tempdir_created = false;

1561

perror("mkdtemp");

2351

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

2352

tempdir = mkdtemp(run_tempdir);

2353

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

2354

if(debug){

2355

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

2356

run_tempdir, old_tempdir);

2357

}

2358

tempdir = mkdtemp(old_tempdir);

2359

}

2360

if(tempdir == NULL){

2361

perror_plus("mkdtemp");

1562

2362

goto end;

1563

2363

}

1564

2364

1566

2366

goto end;

1567

2367

}

1568

2368

1569

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

1570

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

2369

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

2370

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

1571

2371

exitcode = EX_UNAVAILABLE;

1572

2372

goto end;

1573

2373

} else {

1582

2382

/* Connect directly, do not use Zeroconf */

1583

2383

/* (Mainly meant for debugging) */

1584

2384

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

2385

1585

2386

if(address == NULL){

1586

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

2387

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

1587

2388

exitcode = EX_USAGE;

1588

2389

goto end;

1589

2390

}

1592

2393

goto end;

1593

2394

}

1594

2395

1595

uint16_t port;

2396

in_port_t port;

1596

2397

errno = 0;

1597

2398

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

1598

2399

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

1599

or tmpmax != (uint16_t)tmpmax){

1600

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

2400

or tmpmax != (in_port_t)tmpmax){

2401

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

1601

2402

exitcode = EX_USAGE;

1602

2403

goto end;

1603

2404

}

1604

2405

1605

2406

if(quit_now){

1606

2407

goto end;

1607

2408

}

1608

2409

1609

port = (uint16_t)tmpmax;

2410

port = (in_port_t)tmpmax;

1610

2411

*address = '\0';

1611

address = connect_to;

1612

2412

/* Colon in address indicates IPv6 */

1613

2413

int af;

1614

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

2414

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

1615

2415

af = AF_INET6;

2416

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

2417

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

2418

{

2419

connect_to++;

2420

address[-1] = '\0';

2421

}

1616

2422

} else {

1617

2423

af = AF_INET;

1618

2424

}

2425

address = connect_to;

1619

2426

1620

2427

if(quit_now){

1621

2428

goto end;

1622

2429

}

1623

2430

1624

2431

while(not quit_now){

1625

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

2432

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

2433

&mc);

1626

2434

if(quit_now or ret == 0){

1627

2435

break;

1628

2436

}

1629

sleep(15);

1630

};

1631

1632

if (not quit_now){

2437

if(debug){

2438

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

2439

(int)retry_interval);

2440

}

2441

sleep((unsigned int)retry_interval);

2442

}

2443

2444

if(not quit_now){

1633

2445

exitcode = EXIT_SUCCESS;

1634

2446

}

1635

2447

1636

2448

goto end;

1637

2449

}

1638

2450

1650

2462

config.publish_domain = 0;

1651

2463

1652

2464

/* Allocate a new server */

1653

mc.server = avahi_server_new(avahi_simple_poll_get

1654

(mc.simple_poll), &config, NULL,

1655

NULL, &error);

2465

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2466

&config, NULL, NULL, &ret_errno);

1656

2467

1657

2468

/* Free the Avahi configuration data */

1658

2469

avahi_server_config_free(&config);

1660

2471

1661

2472

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

1662

2473

if(mc.server == NULL){

1663

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

1664

avahi_strerror(error));

2474

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

2475

avahi_strerror(ret_errno));

1665

2476

exitcode = EX_UNAVAILABLE;

1666

2477

goto end;

1667

2478

}

1673

2484

/* Create the Avahi service browser */

1674

2485

sb = avahi_s_service_browser_new(mc.server, if_index,

1675

2486

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1676

NULL, 0, browse_callback, NULL);

2487

NULL, 0, browse_callback,

2488

(void *)&mc);

1677

2489

if(sb == NULL){

1678

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

1679

avahi_strerror(avahi_server_errno(mc.server)));

2490

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

2491

avahi_strerror(avahi_server_errno(mc.server)));

1680

2492

exitcode = EX_UNAVAILABLE;

1681

2493

goto end;

1682

2494

}

1688

2500

/* Run the main loop */

1689

2501

1690

2502

if(debug){

1691

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

2503

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

1692

2504

}

1693

2505

1694

avahi_simple_poll_loop(mc.simple_poll);

2506

ret = avahi_loop_with_timeout(simple_poll,

2507

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

2508

if(debug){

2509

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

2510

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

2511

}

1695

2512

1696

2513

end:

1697

2514

1698

2515

if(debug){

1699

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

2516

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

1700

2517

}

1701

2518

1702

2519

/* Cleanup things */

2520

free(mc.interfaces);

2521

1703

2522

if(sb != NULL)

1704

2523

avahi_s_service_browser_free(sb);

1705

2524

1706

2525

if(mc.server != NULL)

1707

2526

avahi_server_free(mc.server);

1708

2527

1709

if(mc.simple_poll != NULL)

1710

avahi_simple_poll_free(mc.simple_poll);

2528

if(simple_poll != NULL)

2529

avahi_simple_poll_free(simple_poll);

1711

2530

1712

2531

if(gnutls_initialized){

1713

2532

gnutls_certificate_free_credentials(mc.cred);

1719

2538

gpgme_release(mc.ctx);

1720

2539

}

1721

2540

1722

/* Take down the network interface */

1723

if(take_down_interface){

1724

/* Re-raise priviliges */

1725

errno = 0;

1726

ret = seteuid(0);

1727

if(ret == -1){

1728

perror("seteuid");

1729

}

1730

if(geteuid() == 0){

1731

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

1732

if(ret == -1){

1733

perror("ioctl SIOCGIFFLAGS");

1734

} else if(network.ifr_flags & IFF_UP) {

1735

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

1736

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

1737

if(ret == -1){

1738

perror("ioctl SIOCSIFFLAGS -IFF_UP");

1739

}

1740

}

1741

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

1742

if(ret == -1){

1743

perror("close");

1744

}

1745

/* Lower privileges permanently */

1746

errno = 0;

1747

ret = setuid(uid);

1748

if(ret == -1){

1749

perror("setuid");

1750

}

1751

}

1752

}

1753

1754

/* Removes the temp directory used by GPGME */

1755

if(tempdir_created){

1756

DIR *d;

1757

struct dirent *direntry;

1758

d = opendir(tempdir);

1759

if(d == NULL){

1760

if(errno != ENOENT){

1761

perror("opendir");

1762

}

1763

} else {

1764

while(true){

1765

direntry = readdir(d);

1766

if(direntry == NULL){

1767

break;

1768

}

1769

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

1770

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

1771

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

1772

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

1773

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

1774

continue;

1775

}

1776

char *fullname = NULL;

1777

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

1778

direntry->d_name);

1779

if(ret < 0){

1780

perror("asprintf");

1781

continue;

1782

}

1783

ret = remove(fullname);

1784

if(ret == -1){

1785

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

1786

strerror(errno));

1787

}

1788

free(fullname);

1789

}

1790

closedir(d);

1791

}

1792

ret = rmdir(tempdir);

1793

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

1794

perror("rmdir");

2541

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

2542

has seen */

2543

if(mc.current_server != NULL){

2544

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

2545

while(mc.current_server != NULL){

2546

server *next = mc.current_server->next;

2547

free(mc.current_server);

2548

mc.current_server = next;

2549

}

2550

}

2551

2552

/* Re-raise privileges */

2553

{

2554

ret_errno = raise_privileges();

2555

if(ret_errno != 0){

2556

perror_plus("Failed to raise privileges");

2557

} else {

2558

2559

/* Run network hooks */

2560

run_network_hooks("stop", interfaces_hooks != NULL ?

2561

interfaces_hooks : "", delay);

2562

2563

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

2564

{

2565

char *interface = NULL;

2566

while((interface=argz_next(interfaces_to_take_down,

2567

interfaces_to_take_down_size,

2568

interface))){

2569

ret_errno = take_down_interface(interface);

2570

if(ret_errno != 0){

2571

errno = ret_errno;

2572

perror_plus("Failed to take down interface");

2573

}

2574

}

2575

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

2576

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

2577

" down\n");

2578

}

2579

}

2580

}

2581

2582

ret_errno = lower_privileges_permanently();

2583

if(ret_errno != 0){

2584

perror_plus("Failed to lower privileges permanently");

2585

}

2586

}

2587

2588

free(interfaces_to_take_down);

2589

free(interfaces_hooks);

2590

2591

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

2592

if(tempdir != NULL){

2593

struct dirent **direntries = NULL;

2594

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

2595

O_NOFOLLOW));

2596

if(tempdir_fd == -1){

2597

perror_plus("open");

2598

} else {

2599

#ifdef __GLIBC__

2600

#if __GLIBC_PREREQ(2, 15)

2601

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

2602

notdotentries, alphasort);

2603

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

2604

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

2605

alphasort);

2606

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

2607

#else /* not __GLIBC__ */

2608

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

2609

alphasort);

2610

#endif /* not __GLIBC__ */

2611

if(numentries > 0){

2612

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

2613

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

2614

if(ret == -1){

2615

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

2616

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

2617

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

2618

}

2619

}

2620

2621

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

2622

free(direntries);

2623

if(numentries == -1){

2624

perror_plus("scandir");

2625

}

2626

ret = rmdir(tempdir);

2627

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

2628

perror_plus("rmdir");

2629

}

2630

}

2631

TEMP_FAILURE_RETRY(close(tempdir_fd));

1795

2632

}

1796

2633

}

1797

2634

1802

2639

&old_sigterm_action,

1803

2640

NULL));

1804

2641

if(ret == -1){

1805

perror("sigaction");

2642

perror_plus("sigaction");

1806

2643

}

1807

2644

do {

1808

2645

ret = raise(signal_received);

1809

2646

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

1810

2647

if(ret != 0){

1811

perror("raise");

2648

perror_plus("raise");

1812

2649

abort();

1813

2650

}

1814

2651

TEMP_FAILURE_RETRY(pause());