/mandos/trunk : revision 237.4.35

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

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stdout, ferror(), remove() */

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

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

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

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

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strtof(), abort() */

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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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*/

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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 <time.h> /* nanosleep(), time() */

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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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if_nametoindex(), IF_NAMESIZE */

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

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

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

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argp_state, struct argp,

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raise() */

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

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EX_NOHOST, EX_IOERR, EX_PROTOCOL */

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

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WEXITSTATUS(), WTERMSIG() */

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

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

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argz_delete(), argz_append(),

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argz_stringify(), argz_add(),

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argz_count() */

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#ifdef __linux__

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96

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

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114

init_gnutls_session(),

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115

GNUTLS_* */

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116

#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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129

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

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130

#define SECKEY "seckey.txt"

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131

#define PUBKEY "pubkey.txt"

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

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133

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bool debug = false;

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135

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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138

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

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139

char *connect_to = NULL;

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const char *hookdir = HOOKDIR;

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uid_t uid = 65534;

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gid_t gid = 65534;

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144

/* 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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159

unsigned int dh_bits;

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gnutls_dh_params_t dh_params;

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const char *priority;

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gpgme_ctx_t ctx;

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server *current_server;

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char *interfaces;

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size_t interfaces_size;

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} mandos_context;

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167

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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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172

int signal_received = 0;

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/* Function to use when printing errors */

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void perror_plus(const char *print_text){

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int e = errno;

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

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program_invocation_short_name);

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errno = e;

180

perror(print_text);

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}

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

184

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

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va_list ap;

186

va_start (ap, format);

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188

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

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program_invocation_short_name));

190

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

191

}

192

152

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/*

153

194

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

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

155

196

* "buffer_length" is how much is already used.

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197

*/

157

198

size_t incbuffer(char **buffer, size_t buffer_length,

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size_t buffer_capacity){

199

size_t buffer_capacity){

159

200

if(buffer_length + BUFFER_SIZE > buffer_capacity){

160

201

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

161

202

if(buffer == NULL){

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207

return buffer_capacity;

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}

168

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

211

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

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int af, server **current_server){

213

int ret;

214

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

215

if(new_server == NULL){

216

perror_plus("malloc");

217

return false;

218

}

219

*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 };

223

if(new_server->ip == NULL){

224

perror_plus("strdup");

225

return false;

226

}

227

/* Special case of first server */

228

if(*current_server == NULL){

229

new_server->next = new_server;

230

new_server->prev = new_server;

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*current_server = new_server;

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

233

} else {

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new_server->next = *current_server;

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

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new_server->prev->next = new_server;

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(*current_server)->prev = new_server;

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}

239

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

240

if(ret == -1){

241

perror_plus("clock_gettime");

242

return false;

243

}

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return true;

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}

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/*

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* Initialize GPGME.

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249

*/

172

static bool init_gpgme(const char *seckey,

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const char *pubkey, const char *tempdir){

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

251

const char *tempdir, mandos_context *mc){

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252

gpgme_error_t rc;

175

253

gpgme_engine_info_t engine_info;

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254

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178

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/*

179

256

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

180

257

*/

185

262

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263

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

187

264

if(fd == -1){

188

perror("open");

265

perror_plus("open");

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266

return false;

190

267

}

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268

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rc = gpgme_data_new_from_fd(&pgp_data, fd);

193

270

if(rc != GPG_ERR_NO_ERROR){

194

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

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gpgme_strsource(rc), gpgme_strerror(rc));

271

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;

197

274

}

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rc = gpgme_op_import(mc.ctx, pgp_data);

276

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

200

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if(rc != GPG_ERR_NO_ERROR){

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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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if(ret == -1){

208

perror("close");

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perror_plus("close");

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}

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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){

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

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

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}

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/* Init GPGME */

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gpgme_check_version(NULL);

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rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

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if(rc != GPG_ERR_NO_ERROR){

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

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302

}

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

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

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rc = gpgme_get_engine_info(&engine_info);

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306

if(rc != GPG_ERR_NO_ERROR){

230

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

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gpgme_strsource(rc), gpgme_strerror(rc));

307

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

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310

}

234

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while(engine_info != NULL){

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engine_info = engine_info->next;

241

318

}

242

319

if(engine_info == NULL){

243

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

320

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

321

tempdir);

244

322

return false;

245

323

}

246

324

247

325

/* Create new GPGME "context" */

248

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

326

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

249

327

if(rc != GPG_ERR_NO_ERROR){

250

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

251

gpgme_strsource(rc), gpgme_strerror(rc));

328

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

329

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

330

gpgme_strerror(rc));

252

331

return false;

253

332

}

254

333

265

344

*/

266

345

static ssize_t pgp_packet_decrypt(const char *cryptotext,

267

346

size_t crypto_size,

268

char **plaintext){

347

char **plaintext,

348

mandos_context *mc){

269

349

gpgme_data_t dh_crypto, dh_plain;

270

350

gpgme_error_t rc;

271

351

ssize_t ret;

273

353

ssize_t plaintext_length = 0;

274

354

275

355

if(debug){

276

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

356

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

277

357

}

278

358

279

359

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

280

360

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

281

361

0);

282

362

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));

363

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

364

gpgme_strsource(rc), gpgme_strerror(rc));

285

365

return -1;

286

366

}

287

367

288

368

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

289

369

rc = gpgme_data_new(&dh_plain);

290

370

if(rc != GPG_ERR_NO_ERROR){

291

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

292

gpgme_strsource(rc), gpgme_strerror(rc));

371

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

372

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

373

gpgme_strsource(rc), gpgme_strerror(rc));

293

374

gpgme_data_release(dh_crypto);

294

375

return -1;

295

376

}

296

377

297

378

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

298

379

data buffer */

299

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

380

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

300

381

if(rc != GPG_ERR_NO_ERROR){

301

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

302

gpgme_strsource(rc), gpgme_strerror(rc));

382

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

383

gpgme_strsource(rc), gpgme_strerror(rc));

303

384

plaintext_length = -1;

304

385

if(debug){

305

386

gpgme_decrypt_result_t result;

306

result = gpgme_op_decrypt_result(mc.ctx);

387

result = gpgme_op_decrypt_result(mc->ctx);

307

388

if(result == NULL){

308

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

389

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

309

390

} 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);

391

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

392

result->unsupported_algorithm);

393

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

394

result->wrong_key_usage);

314

395

if(result->file_name != NULL){

315

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

396

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

316

397

}

317

398

gpgme_recipient_t recipient;

318

399

recipient = result->recipients;

319

400

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");

401

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

402

gpgme_pubkey_algo_name

403

(recipient->pubkey_algo));

404

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

405

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

406

recipient->status == GPG_ERR_NO_SECKEY

407

? "No" : "Yes");

326

408

recipient = recipient->next;

327

409

}

328

410

}

331

413

}

332

414

333

415

if(debug){

334

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

416

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

335

417

}

336

418

337

419

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

338

420

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

339

perror("gpgme_data_seek");

421

perror_plus("gpgme_data_seek");

340

422

plaintext_length = -1;

341

423

goto decrypt_end;

342

424

}

344

426

*plaintext = NULL;

345

427

while(true){

346

428

plaintext_capacity = incbuffer(plaintext,

347

(size_t)plaintext_length,

348

plaintext_capacity);

429

(size_t)plaintext_length,

430

plaintext_capacity);

349

431

if(plaintext_capacity == 0){

350

perror("incbuffer");

351

plaintext_length = -1;

352

goto decrypt_end;

432

perror_plus("incbuffer");

433

plaintext_length = -1;

434

goto decrypt_end;

353

435

}

354

436

355

437

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

360

442

break;

361

443

}

362

444

if(ret < 0){

363

perror("gpgme_data_read");

445

perror_plus("gpgme_data_read");

364

446

plaintext_length = -1;

365

447

goto decrypt_end;

366

448

}

368

450

}

369

451

370

452

if(debug){

371

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

453

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

372

454

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

373

455

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

374

456

}

386

468

}

387

469

388

470

static const char * safer_gnutls_strerror(int value){

389

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

390

-Wunreachable-code */

471

const char *ret = gnutls_strerror(value);

391

472

if(ret == NULL)

392

473

ret = "(unknown)";

393

474

return ret;

396

477

/* GnuTLS log function callback */

397

478

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

398

479

const char* string){

399

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

480

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

400

481

}

401

482

402

483

static int init_gnutls_global(const char *pubkeyfilename,

403

const char *seckeyfilename){

484

const char *seckeyfilename,

485

mandos_context *mc){

404

486

int ret;

405

487

406

488

if(debug){

407

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

489

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

408

490

}

409

491

410

492

ret = gnutls_global_init();

411

493

if(ret != GNUTLS_E_SUCCESS){

412

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

413

safer_gnutls_strerror(ret));

494

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

495

safer_gnutls_strerror(ret));

414

496

return -1;

415

497

}

416

498

423

505

}

424

506

425

507

/* OpenPGP credentials */

426

gnutls_certificate_allocate_credentials(&mc.cred);

508

ret = gnutls_certificate_allocate_credentials(&mc->cred);

427

509

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));

510

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

511

safer_gnutls_strerror(ret));

433

512

gnutls_global_deinit();

434

513

return -1;

435

514

}

436

515

437

516

if(debug){

438

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

439

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

440

seckeyfilename);

517

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

518

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

519

pubkeyfilename,

520

seckeyfilename);

441

521

}

442

522

443

523

ret = gnutls_certificate_set_openpgp_key_file

444

(mc.cred, pubkeyfilename, seckeyfilename,

524

(mc->cred, pubkeyfilename, seckeyfilename,

445

525

GNUTLS_OPENPGP_FMT_BASE64);

446

526

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));

527

fprintf_plus(stderr,

528

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

529

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

530

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

531

safer_gnutls_strerror(ret));

452

532

goto globalfail;

453

533

}

454

534

455

535

/* GnuTLS server initialization */

456

ret = gnutls_dh_params_init(&mc.dh_params);

536

ret = gnutls_dh_params_init(&mc->dh_params);

457

537

if(ret != GNUTLS_E_SUCCESS){

458

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

459

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

538

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

539

" initialization: %s\n",

540

safer_gnutls_strerror(ret));

460

541

goto globalfail;

461

542

}

462

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

543

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

463

544

if(ret != GNUTLS_E_SUCCESS){

464

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

465

safer_gnutls_strerror(ret));

545

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

546

safer_gnutls_strerror(ret));

466

547

goto globalfail;

467

548

}

468

549

469

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

550

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

470

551

471

552

return 0;

472

553

473

554

globalfail:

474

555

475

gnutls_certificate_free_credentials(mc.cred);

556

gnutls_certificate_free_credentials(mc->cred);

476

557

gnutls_global_deinit();

477

gnutls_dh_params_deinit(mc.dh_params);

558

gnutls_dh_params_deinit(mc->dh_params);

478

559

return -1;

479

560

}

480

561

481

static int init_gnutls_session(gnutls_session_t *session){

562

static int init_gnutls_session(gnutls_session_t *session,

563

mandos_context *mc){

482

564

int ret;

483

565

/* GnuTLS session creation */

484

566

do {

488

570

}

489

571

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

490

572

if(ret != GNUTLS_E_SUCCESS){

491

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

492

safer_gnutls_strerror(ret));

573

fprintf_plus(stderr,

574

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

575

safer_gnutls_strerror(ret));

493

576

}

494

577

495

578

{

496

579

const char *err;

497

580

do {

498

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

581

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

499

582

if(quit_now){

500

583

gnutls_deinit(*session);

501

584

return -1;

502

585

}

503

586

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

504

587

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));

588

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

589

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

590

safer_gnutls_strerror(ret));

508

591

gnutls_deinit(*session);

509

592

return -1;

510

593

}

512

595

513

596

do {

514

597

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

515

mc.cred);

598

mc->cred);

516

599

if(quit_now){

517

600

gnutls_deinit(*session);

518

601

return -1;

519

602

}

520

603

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

521

604

if(ret != GNUTLS_E_SUCCESS){

522

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

523

safer_gnutls_strerror(ret));

605

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

606

safer_gnutls_strerror(ret));

524

607

gnutls_deinit(*session);

525

608

return -1;

526

609

}

528

611

/* ignore client certificate if any. */

529

612

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

530

613

531

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

614

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

532

615

533

616

return 0;

534

617

}

538

621

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

539

622

540

623

/* Called when a Mandos server is found */

541

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

624

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

542

625

AvahiIfIndex if_index,

543

int af){

626

int af, mandos_context *mc){

544

627

int ret, tcp_sd = -1;

545

628

ssize_t sret;

546

629

union {

571

654

pf = PF_INET;

572

655

break;

573

656

default:

574

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

657

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

575

658

errno = EINVAL;

576

659

return -1;

577

660

}

578

661

579

ret = init_gnutls_session(&session);

662

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

663

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

664

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

665

bool match = false;

666

{

667

char *interface = NULL;

668

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

669

interface))){

670

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

671

match = true;

672

break;

673

}

674

}

675

}

676

if(not match){

677

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

678

connect to the server */

679

if(debug){

680

char interface[IF_NAMESIZE];

681

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

682

perror_plus("if_indextoname");

683

} else {

684

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

685

" \"%s\"\n",

686

if_indextoname((unsigned int)if_index,

687

interface));

688

}

689

}

690

return -1;

691

}

692

}

693

694

ret = init_gnutls_session(&session, mc);

580

695

if(ret != 0){

581

696

return -1;

582

697

}

583

698

584

699

if(debug){

585

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

586

"\n", ip, port);

700

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

701

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

587

702

}

588

703

589

704

tcp_sd = socket(pf, SOCK_STREAM, 0);

590

705

if(tcp_sd < 0){

591

706

int e = errno;

592

perror("socket");

707

perror_plus("socket");

593

708

errno = e;

594

709

goto mandos_end;

595

710

}

609

724

}

610

725

if(ret < 0 ){

611

726

int e = errno;

612

perror("inet_pton");

727

perror_plus("inet_pton");

613

728

errno = e;

614

729

goto mandos_end;

615

730

}

616

731

if(ret == 0){

617

732

int e = errno;

618

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

733

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

619

734

errno = e;

620

735

goto mandos_end;

621

736

}

622

737

if(af == AF_INET6){

623

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

624

-Wconversion and

625

-Wunreachable-code */

626

738

to.in6.sin6_port = htons(port);

627

739

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

628

740

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

629

-Wunreachable-code*/

741

-Wunreachable-code*/

630

742

if(if_index == AVAHI_IF_UNSPEC){

631

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

632

" without a network interface\n");

743

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

744

" incomplete without a network interface\n");

633

745

errno = EINVAL;

634

746

goto mandos_end;

635

747

}

651

763

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

652

764

char interface[IF_NAMESIZE];

653

765

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

654

perror("if_indextoname");

766

perror_plus("if_indextoname");

655

767

} else {

656

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

657

ip, interface, port);

768

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

769

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

658

770

}

659

771

} else {

660

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

661

port);

772

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

773

ip, (uintmax_t)port);

662

774

}

663

775

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

664

776

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

671

783

sizeof(addrstr));

672

784

}

673

785

if(pcret == NULL){

674

perror("inet_ntop");

786

perror_plus("inet_ntop");

675

787

} else {

676

788

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

677

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

789

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

678

790

}

679

791

}

680

792

}

690

802

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

691

803

}

692

804

if(ret < 0){

693

int e = errno;

694

perror("connect");

695

errno = e;

805

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

806

int e = errno;

807

perror_plus("connect");

808

errno = e;

809

}

696

810

goto mandos_end;

697

811

}

698

812

706

820

while(true){

707

821

size_t out_size = strlen(out);

708

822

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

709

out_size - written));

823

out_size - written));

710

824

if(ret == -1){

711

825

int e = errno;

712

perror("write");

826

perror_plus("write");

713

827

errno = e;

714

828

goto mandos_end;

715

829

}

732

846

}

733

847

734

848

if(debug){

735

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

849

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

736

850

}

737

851

738

852

if(quit_now){

740

854

goto mandos_end;

741

855

}

742

856

743

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

857

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

858

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

859

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

860

gnutls_transport_set_ptr(session,

861

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

744

862

745

863

if(quit_now){

746

864

errno = EINTR;

757

875

758

876

if(ret != GNUTLS_E_SUCCESS){

759

877

if(debug){

760

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

878

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

761

879

gnutls_perror(ret);

762

880

}

763

881

errno = EPROTO;

767

885

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

768

886

769

887

if(debug){

770

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

771

ip);

888

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

889

" %s\n", ip);

772

890

}

773

891

774

892

while(true){

779

897

}

780

898

781

899

buffer_capacity = incbuffer(&buffer, buffer_length,

782

buffer_capacity);

900

buffer_capacity);

783

901

if(buffer_capacity == 0){

784

902

int e = errno;

785

perror("incbuffer");

903

perror_plus("incbuffer");

786

904

errno = e;

787

905

goto mandos_end;

788

906

}

812

930

}

813

931

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

814

932

if(ret < 0){

815

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

933

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

934

"***\n");

816

935

gnutls_perror(ret);

817

936

errno = EPROTO;

818

937

goto mandos_end;

819

938

}

820

939

break;

821

940

default:

822

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

823

" encrypted session with Mandos server\n");

941

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

942

" encrypted session with Mandos server\n");

824

943

gnutls_bye(session, GNUTLS_SHUT_RDWR);

825

944

errno = EIO;

826

945

goto mandos_end;

831

950

}

832

951

833

952

if(debug){

834

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

953

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

835

954

}

836

955

837

956

if(quit_now){

849

968

850

969

if(buffer_length > 0){

851

970

ssize_t decrypted_buffer_size;

852

decrypted_buffer_size = pgp_packet_decrypt(buffer,

853

buffer_length,

854

&decrypted_buffer);

971

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

972

&decrypted_buffer, mc);

855

973

if(decrypted_buffer_size >= 0){

856

974

857

975

written = 0;

867

985

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

868

986

int e = errno;

869

987

if(debug){

870

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

871

strerror(errno));

988

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

989

strerror(errno));

872

990

}

873

991

errno = e;

874

992

goto mandos_end;

893

1011

if(e == 0){

894

1012

e = errno;

895

1013

}

896

perror("close");

1014

perror_plus("close");

897

1015

}

898

1016

gnutls_deinit(session);

1017

errno = e;

899

1018

if(quit_now){

900

e = EINTR;

1019

errno = EINTR;

901

1020

retval = -1;

902

1021

}

903

errno = e;

904

1022

}

905

1023

return retval;

906

1024

}

918

1036

AVAHI_GCC_UNUSED AvahiStringList *txt,

919

1037

AVAHI_GCC_UNUSED AvahiLookupResultFlags

920

1038

flags,

921

AVAHI_GCC_UNUSED void* userdata){

922

assert(r);

1039

void* mc){

1040

if(r == NULL){

1041

return;

1042

}

923

1043

924

1044

/* Called whenever a service has been resolved successfully or

925

1045

timed out */

931

1051

switch(event){

932

1052

default:

933

1053

case AVAHI_RESOLVER_FAILURE:

934

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

935

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

936

avahi_strerror(avahi_server_errno(mc.server)));

1054

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

1055

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

1056

domain,

1057

avahi_strerror(avahi_server_errno

1058

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

937

1059

break;

938

1060

939

1061

case AVAHI_RESOLVER_FOUND:

941

1063

char ip[AVAHI_ADDRESS_STR_MAX];

942

1064

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

943

1065

if(debug){

944

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

945

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

946

ip, (intmax_t)interface, port);

1066

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

1067

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

1068

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

947

1069

}

948

int ret = start_mandos_communication(ip, port, interface,

949

avahi_proto_to_af(proto));

1070

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

1071

interface,

1072

avahi_proto_to_af(proto),

1073

mc);

950

1074

if(ret == 0){

951

avahi_simple_poll_quit(mc.simple_poll);

1075

avahi_simple_poll_quit(simple_poll);

1076

} else {

1077

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

1078

avahi_proto_to_af(proto),

1079

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

1080

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

1081

" list\n", name);

1082

}

952

1083

}

953

1084

}

954

1085

}

964

1095

const char *domain,

965

1096

AVAHI_GCC_UNUSED AvahiLookupResultFlags

966

1097

flags,

967

AVAHI_GCC_UNUSED void* userdata){

968

assert(b);

1098

void* mc){

1099

if(b == NULL){

1100

return;

1101

}

969

1102

970

1103

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

971

1104

is removed from the LAN */

978

1111

default:

979

1112

case AVAHI_BROWSER_FAILURE:

980

1113

981

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

982

avahi_strerror(avahi_server_errno(mc.server)));

983

avahi_simple_poll_quit(mc.simple_poll);

1114

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

1115

avahi_strerror(avahi_server_errno

1116

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

1117

avahi_simple_poll_quit(simple_poll);

984

1118

return;

985

1119

986

1120

case AVAHI_BROWSER_NEW:

989

1123

the callback function is called the Avahi server will free the

990

1124

resolver for us. */

991

1125

992

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

993

name, type, domain, protocol, 0,

994

resolve_callback, NULL) == NULL)

995

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

996

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

1126

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

1127

interface, protocol, name, type,

1128

domain, protocol, 0,

1129

resolve_callback, mc) == NULL)

1130

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

1131

" %s\n", name,

1132

avahi_strerror(avahi_server_errno

1133

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

997

1134

break;

998

1135

999

1136

case AVAHI_BROWSER_REMOVE:

1002

1139

case AVAHI_BROWSER_ALL_FOR_NOW:

1003

1140

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1004

1141

if(debug){

1005

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

1142

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

1143

" searching...\n");

1006

1144

}

1007

1145

break;

1008

1146

}

1009

1147

}

1010

1148

1011

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

1149

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

1012

1150

static void handle_sigterm(int sig){

1013

1151

if(quit_now){

1014

1152

return;

1016

1154

quit_now = 1;

1017

1155

signal_received = sig;

1018

1156

int old_errno = errno;

1019

if(mc.simple_poll != NULL){

1020

avahi_simple_poll_quit(mc.simple_poll);

1157

/* set main loop to exit */

1158

if(simple_poll != NULL){

1159

avahi_simple_poll_quit(simple_poll);

1021

1160

}

1022

1161

errno = old_errno;

1023

1162

}

1024

1163

1164

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

1165

int ret;

1166

error_t ret_errno;

1167

1168

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

1169

if(s < 0){

1170

ret_errno = errno;

1171

perror_plus("socket");

1172

errno = ret_errno;

1173

return false;

1174

}

1175

strcpy(ifr->ifr_name, ifname);

1176

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1177

if(ret == -1){

1178

if(debug){

1179

ret_errno = errno;

1180

perror_plus("ioctl SIOCGIFFLAGS");

1181

errno = ret_errno;

1182

}

1183

return false;

1184

}

1185

return true;

1186

}

1187

1188

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

1189

1190

/* Reject the loopback device */

1191

if(ifr->ifr_flags & IFF_LOOPBACK){

1192

if(debug){

1193

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

1194

ifname);

1195

}

1196

return false;

1197

}

1198

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

1199

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

1200

if(debug){

1201

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

1202

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

1203

}

1204

return true;

1205

}

1206

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

1207

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

1208

if(debug){

1209

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1210

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

1211

}

1212

return false;

1213

}

1214

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

1215

if(ifr->ifr_flags & IFF_NOARP){

1216

if(debug){

1217

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

1218

ifname);

1219

}

1220

return false;

1221

}

1222

1223

/* Accept this device */

1224

if(debug){

1225

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

1226

}

1227

return true;

1228

}

1229

1025

1230

/*

1026

1231

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

1027

1232

* corresponds to an acceptable network device.

1028

1233

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

1029

1234

*/

1030

1235

int good_interface(const struct dirent *if_entry){

1031

ssize_t ssret;

1032

char *flagname = NULL;

1033

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

1034

if_entry->d_name);

1035

if(ret < 0){

1036

perror("asprintf");

1037

return 0;

1038

}

1039

1236

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

1040

1237

return 0;

1041

1238

}

1042

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

1043

if(flags_fd == -1){

1044

perror("open");

1045

return 0;

1046

}

1047

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

1048

/* read line from flags_fd */

1049

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

1050

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

1051

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

1052

if(flagstring == NULL){

1053

perror("malloc");

1054

close(flags_fd);

1055

return 0;

1056

}

1057

while(to_read > 0){

1058

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

1059

(size_t)to_read));

1060

if(ssret == -1){

1061

perror("read");

1062

free(flagstring);

1063

close(flags_fd);

1064

return 0;

1065

}

1066

to_read -= ssret;

1067

if(ssret == 0){

1239

1240

struct ifreq ifr;

1241

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

1242

if(debug){

1243

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

1244

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

1245

}

1246

return 0;

1247

}

1248

1249

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

1250

return 0;

1251

}

1252

return 1;

1253

}

1254

1255

/*

1256

* This function determines if a network interface is up.

1257

*/

1258

bool interface_is_up(const char *interface){

1259

struct ifreq ifr;

1260

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

1261

if(debug){

1262

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

1263

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

1264

}

1265

return false;

1266

}

1267

1268

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

1269

}

1270

1271

/*

1272

* This function determines if a network interface is running

1273

*/

1274

bool interface_is_running(const char *interface){

1275

struct ifreq ifr;

1276

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

1277

if(debug){

1278

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

1279

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

1280

}

1281

return false;

1282

}

1283

1284

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

1285

}

1286

1287

int notdotentries(const struct dirent *direntry){

1288

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

1289

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

1290

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

1291

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

1292

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

1293

return 0;

1294

}

1295

return 1;

1296

}

1297

1298

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

1299

int runnable_hook(const struct dirent *direntry){

1300

int ret;

1301

size_t sret;

1302

struct stat st;

1303

1304

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

1305

/* Empty name? */

1306

return 0;

1307

}

1308

1309

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

1310

"abcdefghijklmnopqrstuvwxyz"

1311

"0123456789"

1312

"_-");

1313

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

1314

/* Contains non-allowed characters */

1315

if(debug){

1316

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

1317

direntry->d_name);

1318

}

1319

return 0;

1320

}

1321

1322

char *fullname = NULL;

1323

ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);

1324

if(ret < 0){

1325

perror_plus("asprintf");

1326

return 0;

1327

}

1328

1329

ret = stat(fullname, &st);

1330

if(ret == -1){

1331

if(debug){

1332

perror_plus("Could not stat hook");

1333

}

1334

return 0;

1335

}

1336

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

1337

/* Not a regular file */

1338

if(debug){

1339

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

1340

direntry->d_name);

1341

}

1342

return 0;

1343

}

1344

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

1345

/* Not executable */

1346

if(debug){

1347

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

1348

direntry->d_name);

1349

}

1350

return 0;

1351

}

1352

if(debug){

1353

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

1354

direntry->d_name);

1355

}

1356

return 1;

1357

}

1358

1359

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1360

mandos_context *mc){

1361

int ret;

1362

struct timespec now;

1363

struct timespec waited_time;

1364

intmax_t block_time;

1365

1366

while(true){

1367

if(mc->current_server == NULL){

1368

if (debug){

1369

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

1370

" No timeout!\n");

1371

}

1372

ret = avahi_simple_poll_iterate(s, -1);

1373

} else {

1374

if (debug){

1375

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

1376

" it, or wait\n");

1377

}

1378

/* the current time */

1379

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1380

if(ret == -1){

1381

perror_plus("clock_gettime");

1382

return -1;

1383

}

1384

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

1385

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

1386

waited_time.tv_sec = (now.tv_sec

1387

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

1388

waited_time.tv_nsec = (now.tv_nsec

1389

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

1390

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

1391

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

1392

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

1393

block_time = ((retry_interval

1394

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

1395

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

1396

1397

if (debug){

1398

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

1399

block_time);

1400

}

1401

1402

if(block_time <= 0){

1403

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

1404

mc->current_server->port,

1405

mc->current_server->if_index,

1406

mc->current_server->af, mc);

1407

if(ret == 0){

1408

avahi_simple_poll_quit(s);

1409

return 0;

1410

}

1411

ret = clock_gettime(CLOCK_MONOTONIC,

1412

&mc->current_server->last_seen);

1413

if(ret == -1){

1414

perror_plus("clock_gettime");

1415

return -1;

1416

}

1417

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

1418

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

1419

servers, but don't block */

1420

}

1421

1422

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

1423

}

1424

if(ret != 0){

1425

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

1426

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

1427

}

1428

}

1429

}

1430

}

1431

1432

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

1433

error_t raise_privileges(void){

1434

error_t old_errno = errno;

1435

error_t ret_errno = 0;

1436

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

1437

ret_errno = errno;

1438

perror_plus("seteuid");

1439

}

1440

errno = old_errno;

1441

return ret_errno;

1442

}

1443

1444

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

1445

error_t raise_privileges_permanently(void){

1446

error_t old_errno = errno;

1447

error_t ret_errno = raise_privileges();

1448

if(ret_errno != 0){

1449

errno = old_errno;

1450

return ret_errno;

1451

}

1452

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

1453

ret_errno = errno;

1454

perror_plus("seteuid");

1455

}

1456

errno = old_errno;

1457

return ret_errno;

1458

}

1459

1460

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

1461

error_t lower_privileges(void){

1462

error_t old_errno = errno;

1463

error_t ret_errno = 0;

1464

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

1465

ret_errno = errno;

1466

perror_plus("seteuid");

1467

}

1468

errno = old_errno;

1469

return ret_errno;

1470

}

1471

1472

/* Lower privileges permanently */

1473

error_t lower_privileges_permanently(void){

1474

error_t old_errno = errno;

1475

error_t ret_errno = 0;

1476

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

1477

ret_errno = errno;

1478

perror_plus("setuid");

1479

}

1480

errno = old_errno;

1481

return ret_errno;

1482

}

1483

1484

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

1485

const float delay){

1486

struct dirent **direntries;

1487

struct dirent *direntry;

1488

int ret;

1489

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

1490

alphasort);

1491

if(numhooks == -1){

1492

if(errno == ENOENT){

1493

if(debug){

1494

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

1495

" found\n", hookdir);

1496

}

1497

} else {

1498

perror_plus("scandir");

1499

}

1500

} else {

1501

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

1502

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

1503

direntry = direntries[i];

1504

char *fullname = NULL;

1505

ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);

1506

if(ret < 0){

1507

perror_plus("asprintf");

1508

continue;

1509

}

1510

if(debug){

1511

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

1512

direntry->d_name);

1513

}

1514

pid_t hook_pid = fork();

1515

if(hook_pid == 0){

1516

/* Child */

1517

/* Raise privileges */

1518

raise_privileges_permanently();

1519

/* Set group */

1520

errno = 0;

1521

ret = setgid(0);

1522

if(ret == -1){

1523

perror_plus("setgid");

1524

}

1525

/* Reset supplementary groups */

1526

errno = 0;

1527

ret = setgroups(0, NULL);

1528

if(ret == -1){

1529

perror_plus("setgroups");

1530

}

1531

dup2(devnull, STDIN_FILENO);

1532

close(devnull);

1533

dup2(STDERR_FILENO, STDOUT_FILENO);

1534

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

1535

if(ret == -1){

1536

perror_plus("setenv");

1537

_exit(EX_OSERR);

1538

}

1539

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

1540

if(ret == -1){

1541

perror_plus("setenv");

1542

_exit(EX_OSERR);

1543

}

1544

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

1545

if(ret == -1){

1546

perror_plus("setenv");

1547

_exit(EX_OSERR);

1548

}

1549

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

1550

if(ret == -1){

1551

perror_plus("setenv");

1552

_exit(EX_OSERR);

1553

}

1554

char *delaystring;

1555

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

1556

if(ret == -1){

1557

perror_plus("asprintf");

1558

_exit(EX_OSERR);

1559

}

1560

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

1561

if(ret == -1){

1562

free(delaystring);

1563

perror_plus("setenv");

1564

_exit(EX_OSERR);

1565

}

1566

free(delaystring);

1567

if(connect_to != NULL){

1568

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

1569

if(ret == -1){

1570

perror_plus("setenv");

1571

_exit(EX_OSERR);

1572

}

1573

}

1574

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

1575

perror_plus("execl");

1576

_exit(EXIT_FAILURE);

1577

}

1578

} else {

1579

int status;

1580

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

1581

perror_plus("waitpid");

1582

free(fullname);

1583

continue;

1584

}

1585

if(WIFEXITED(status)){

1586

if(WEXITSTATUS(status) != 0){

1587

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

1588

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

1589

WEXITSTATUS(status));

1590

free(fullname);

1591

continue;

1592

}

1593

} else if(WIFSIGNALED(status)){

1594

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

1595

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

1596

WTERMSIG(status));

1597

free(fullname);

1598

continue;

1599

} else {

1600

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

1601

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

1602

free(fullname);

1603

continue;

1604

}

1605

}

1606

free(fullname);

1607

if(debug){

1608

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

1609

direntry->d_name);

1610

}

1611

}

1612

close(devnull);

1613

}

1614

return true;

1615

}

1616

1617

error_t bring_up_interface(const char *const interface,

1618

const float delay){

1619

int sd = -1;

1620

error_t old_errno = errno;

1621

error_t ret_errno = 0;

1622

int ret, ret_setflags;

1623

struct ifreq network;

1624

unsigned int if_index = if_nametoindex(interface);

1625

if(if_index == 0){

1626

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

1627

errno = old_errno;

1628

return ENXIO;

1629

}

1630

1631

if(quit_now){

1632

errno = old_errno;

1633

return EINTR;

1634

}

1635

1636

if(not interface_is_up(interface)){

1637

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

1638

ret_errno = errno;

1639

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

1640

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

1641

return ret_errno;

1642

}

1643

network.ifr_flags |= IFF_UP;

1644

1645

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1646

if(sd < 0){

1647

ret_errno = errno;

1648

perror_plus("socket");

1649

errno = old_errno;

1650

return ret_errno;

1651

}

1652

1653

if(quit_now){

1654

close(sd);

1655

errno = old_errno;

1656

return EINTR;

1657

}

1658

1659

if(debug){

1660

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

1661

interface);

1662

}

1663

1664

/* Raise priviliges */

1665

raise_privileges();

1666

1667

#ifdef __linux__

1668

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1669

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

1670

int ret_linux = klogctl(8, NULL, 5);

1671

bool restore_loglevel = true;

1672

if(ret_linux == -1){

1673

restore_loglevel = false;

1674

perror_plus("klogctl");

1675

}

1676

#endif /* __linux__ */

1677

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

1678

ret_errno = errno;

1679

#ifdef __linux__

1680

if(restore_loglevel){

1681

ret_linux = klogctl(7, NULL, 0);

1682

if(ret_linux == -1){

1683

perror_plus("klogctl");

1684

}

1685

}

1686

#endif /* __linux__ */

1687

1688

/* Lower privileges */

1689

lower_privileges();

1690

1691

/* Close the socket */

1692

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

1693

if(ret == -1){

1694

perror_plus("close");

1695

}

1696

1697

if(ret_setflags == -1){

1698

errno = ret_errno;

1699

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1700

errno = old_errno;

1701

return ret_errno;

1702

}

1703

} else if(debug){

1704

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

1705

interface);

1706

}

1707

1708

/* Sleep checking until interface is running.

1709

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

1710

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

1711

if(interface_is_running(interface)){

1068

1712

break;

1069

1713

}

1070

}

1071

close(flags_fd);

1072

intmax_t tmpmax;

1073

char *tmp;

1074

errno = 0;

1075

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

1076

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

1077

and not (isspace(*tmp)))

1078

or tmpmax != (ifreq_flags)tmpmax){

1079

if(debug){

1080

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

1081

flagstring, if_entry->d_name);

1082

}

1083

free(flagstring);

1084

return 0;

1085

}

1086

free(flagstring);

1087

ifreq_flags flags = (ifreq_flags)tmpmax;

1088

/* Reject the loopback device */

1089

if(flags & IFF_LOOPBACK){

1090

if(debug){

1091

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

1092

if_entry->d_name);

1093

}

1094

return 0;

1095

}

1096

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

1097

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

1098

if(debug){

1099

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

1100

if_entry->d_name);

1101

}

1102

return 1;

1103

}

1104

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

1105

if(not (flags & IFF_BROADCAST)){

1106

if(debug){

1107

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

1108

if_entry->d_name);

1109

}

1110

return 0;

1111

}

1112

/* Accept this device */

1113

if(debug){

1114

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

1115

if_entry->d_name);

1116

}

1117

return 1;

1714

struct timespec sleeptime = { .tv_nsec = 250000000 };

1715

ret = nanosleep(&sleeptime, NULL);

1716

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

1717

perror_plus("nanosleep");

1718

}

1719

}

1720

1721

errno = old_errno;

1722

return 0;

1723

}

1724

1725

error_t take_down_interface(const char *const interface){

1726

int sd = -1;

1727

error_t old_errno = errno;

1728

error_t ret_errno = 0;

1729

int ret, ret_setflags;

1730

struct ifreq network;

1731

unsigned int if_index = if_nametoindex(interface);

1732

if(if_index == 0){

1733

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

1734

errno = old_errno;

1735

return ENXIO;

1736

}

1737

if(interface_is_up(interface)){

1738

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

1739

ret_errno = errno;

1740

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

1741

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

1742

return ret_errno;

1743

}

1744

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

1745

1746

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1747

if(sd < 0){

1748

ret_errno = errno;

1749

perror_plus("socket");

1750

errno = old_errno;

1751

return ret_errno;

1752

}

1753

1754

if(debug){

1755

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

1756

interface);

1757

}

1758

1759

/* Raise priviliges */

1760

raise_privileges();

1761

1762

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

1763

ret_errno = errno;

1764

1765

/* Lower privileges */

1766

lower_privileges();

1767

1768

/* Close the socket */

1769

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

1770

if(ret == -1){

1771

perror_plus("close");

1772

}

1773

1774

if(ret_setflags == -1){

1775

errno = ret_errno;

1776

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1777

errno = old_errno;

1778

return ret_errno;

1779

}

1780

} else if(debug){

1781

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

1782

interface);

1783

}

1784

1785

errno = old_errno;

1786

return 0;

1118

1787

}

1119

1788

1120

1789

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

1790

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

1791

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

1792

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

1793

.interfaces = NULL, .interfaces_size = 0 };

1121

1794

AvahiSServiceBrowser *sb = NULL;

1122

int error;

1795

error_t ret_errno;

1123

1796

int ret;

1124

1797

intmax_t tmpmax;

1125

1798

char *tmp;

1126

1799

int exitcode = EXIT_SUCCESS;

1127

const char *interface = "";

1128

struct ifreq network;

1129

int sd = -1;

1130

bool take_down_interface = false;

1131

uid_t uid;

1132

gid_t gid;

1800

char *interfaces_to_take_down = NULL;

1801

size_t interfaces_to_take_down_size = 0;

1133

1802

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

1134

1803

bool tempdir_created = false;

1135

1804

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1136

1805

const char *seckey = PATHDIR "/" SECKEY;

1137

1806

const char *pubkey = PATHDIR "/" PUBKEY;

1807

char *interfaces_hooks = NULL;

1808

size_t interfaces_hooks_size = 0;

1138

1809

1139

1810

bool gnutls_initialized = false;

1140

1811

bool gpgme_initialized = false;

1141

1812

float delay = 2.5f;

1813

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

1814

retrying the same server again */

1142

1815

1143

1816

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1144

1817

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1150

1823

errno = 0;

1151

1824

ret = setgid(gid);

1152

1825

if(ret == -1){

1153

perror("setgid");

1826

perror_plus("setgid");

1154

1827

}

1155

1828

1156

1829

/* Lower user privileges (temporarily) */

1157

1830

errno = 0;

1158

1831

ret = seteuid(uid);

1159

1832

if(ret == -1){

1160

perror("seteuid");

1833

perror_plus("seteuid");

1161

1834

}

1162

1835

1163

1836

if(quit_now){

1198

1871

.arg = "SECONDS",

1199

1872

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

1200

1873

.group = 2 },

1874

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

1875

.arg = "SECONDS",

1876

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

1877

.group = 2 },

1878

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

1879

.arg = "DIR",

1880

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

1881

.group = 2 },

1201

1882

/*

1202

1883

* These reproduce what we would get without ARGP_NO_HELP

1203

1884

*/

1221

1902

connect_to = arg;

1222

1903

break;

1223

1904

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

1224

interface = arg;

1905

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

1906

arg, (int)',');

1907

if(ret_errno != 0){

1908

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

1909

}

1225

1910

break;

1226

1911

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

1227

1912

seckey = arg;

1247

1932

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

1248

1933

argp_error(state, "Bad delay");

1249

1934

}

1935

case 132: /* --retry */

1936

errno = 0;

1937

retry_interval = strtod(arg, &tmp);

1938

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

1939

or (retry_interval * 1000) > INT_MAX

1940

or retry_interval < 0){

1941

argp_error(state, "Bad retry interval");

1942

}

1943

break;

1944

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

1945

hookdir = arg;

1250

1946

break;

1251

1947

/*

1252

1948

* These reproduce what we would get without ARGP_NO_HELP

1259

1955

argp_state_help(state, state->out_stream,

1260

1956

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1261

1957

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

1262

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

1958

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

1263

1959

exit(argp_err_exit_status);

1264

1960

break;

1265

1961

default:

1280

1976

case ENOMEM:

1281

1977

default:

1282

1978

errno = ret;

1283

perror("argp_parse");

1979

perror_plus("argp_parse");

1284

1980

exitcode = EX_OSERR;

1285

1981

goto end;

1286

1982

case EINVAL:

1288

1984

goto end;

1289

1985

}

1290

1986

}

1987

1988

{

1989

/* Work around Debian bug #633582:

1990

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

1991

1992

/* Re-raise priviliges */

1993

if(raise_privileges() == 0){

1994

struct stat st;

1995

1996

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

1997

int seckey_fd = open(seckey, O_RDONLY);

1998

if(seckey_fd == -1){

1999

perror_plus("open");

2000

} else {

2001

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

2002

if(ret == -1){

2003

perror_plus("fstat");

2004

} else {

2005

if(S_ISREG(st.st_mode)

2006

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

2007

ret = fchown(seckey_fd, uid, gid);

2008

if(ret == -1){

2009

perror_plus("fchown");

2010

}

2011

}

2012

}

2013

TEMP_FAILURE_RETRY(close(seckey_fd));

2014

}

2015

}

2016

2017

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

2018

int pubkey_fd = open(pubkey, O_RDONLY);

2019

if(pubkey_fd == -1){

2020

perror_plus("open");

2021

} else {

2022

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

2023

if(ret == -1){

2024

perror_plus("fstat");

2025

} else {

2026

if(S_ISREG(st.st_mode)

2027

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

2028

ret = fchown(pubkey_fd, uid, gid);

2029

if(ret == -1){

2030

perror_plus("fchown");

2031

}

2032

}

2033

}

2034

TEMP_FAILURE_RETRY(close(pubkey_fd));

2035

}

2036

}

2037

2038

/* Lower privileges */

2039

lower_privileges();

2040

}

2041

}

2042

2043

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

2044

{

2045

char *interface = NULL;

2046

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

2047

interface))){

2048

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

2049

and if_nametoindex(interface) == 0){

2050

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

2051

fprintf_plus(stderr, "Not using nonexisting interface"

2052

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

2053

}

2054

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

2055

interface = NULL;

2056

}

2057

}

2058

}

2059

2060

/* Run network hooks */

2061

{

2062

if(mc.interfaces != NULL){

2063

interfaces_hooks = malloc(mc.interfaces_size);

2064

if(interfaces_hooks == NULL){

2065

perror_plus("malloc");

2066

goto end;

2067

}

2068

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

2069

interfaces_hooks_size = mc.interfaces_size;

2070

argz_stringify(interfaces_hooks, interfaces_hooks_size,

2071

(int)',');

2072

}

2073

if(not run_network_hooks("start", interfaces_hooks != NULL ?

2074

interfaces_hooks : "", delay)){

2075

goto end;

2076

}

2077

}

1291

2078

1292

2079

if(not debug){

1293

2080

avahi_set_log_function(empty_log);

1294

2081

}

1295

1296

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

1297

struct dirent **direntries;

1298

ret = scandir(sys_class_net, &direntries, good_interface,

1299

alphasort);

1300

if(ret >= 1){

1301

/* Pick the first good interface */

1302

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

1303

if(debug){

1304

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

1305

}

1306

if(interface == NULL){

1307

perror("malloc");

1308

free(direntries);

1309

exitcode = EXIT_FAILURE;

1310

goto end;

1311

}

1312

free(direntries);

1313

} else {

1314

free(direntries);

1315

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

1316

exitcode = EXIT_FAILURE;

1317

goto end;

1318

}

1319

}

1320

2082

1321

2083

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

1322

2084

from the signal handler */

1323

2085

/* Initialize the pseudo-RNG for Avahi */

1324

2086

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

1325

mc.simple_poll = avahi_simple_poll_new();

1326

if(mc.simple_poll == NULL){

1327

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

2087

simple_poll = avahi_simple_poll_new();

2088

if(simple_poll == NULL){

2089

fprintf_plus(stderr,

2090

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

1328

2091

exitcode = EX_UNAVAILABLE;

1329

2092

goto end;

1330

2093

}

1332

2095

sigemptyset(&sigterm_action.sa_mask);

1333

2096

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

1334

2097

if(ret == -1){

1335

perror("sigaddset");

2098

perror_plus("sigaddset");

1336

2099

exitcode = EX_OSERR;

1337

2100

goto end;

1338

2101

}

1339

2102

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

1340

2103

if(ret == -1){

1341

perror("sigaddset");

2104

perror_plus("sigaddset");

1342

2105

exitcode = EX_OSERR;

1343

2106

goto end;

1344

2107

}

1345

2108

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

1346

2109

if(ret == -1){

1347

perror("sigaddset");

2110

perror_plus("sigaddset");

1348

2111

exitcode = EX_OSERR;

1349

2112

goto end;

1350

2113

}

1354

2117

*/

1355

2118

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

1356

2119

if(ret == -1){

1357

perror("sigaction");

2120

perror_plus("sigaction");

1358

2121

return EX_OSERR;

1359

2122

}

1360

2123

if(old_sigterm_action.sa_handler != SIG_IGN){

1361

2124

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

1362

2125

if(ret == -1){

1363

perror("sigaction");

2126

perror_plus("sigaction");

1364

2127

exitcode = EX_OSERR;

1365

2128

goto end;

1366

2129

}

1367

2130

}

1368

2131

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

1369

2132

if(ret == -1){

1370

perror("sigaction");

2133

perror_plus("sigaction");

1371

2134

return EX_OSERR;

1372

2135

}

1373

2136

if(old_sigterm_action.sa_handler != SIG_IGN){

1374

2137

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

1375

2138

if(ret == -1){

1376

perror("sigaction");

2139

perror_plus("sigaction");

1377

2140

exitcode = EX_OSERR;

1378

2141

goto end;

1379

2142

}

1380

2143

}

1381

2144

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

1382

2145

if(ret == -1){

1383

perror("sigaction");

2146

perror_plus("sigaction");

1384

2147

return EX_OSERR;

1385

2148

}

1386

2149

if(old_sigterm_action.sa_handler != SIG_IGN){

1387

2150

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

1388

2151

if(ret == -1){

1389

perror("sigaction");

1390

exitcode = EX_OSERR;

1391

goto end;

1392

}

1393

}

1394

1395

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

1396

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

1397

if_index = (AvahiIfIndex) if_nametoindex(interface);

1398

if(if_index == 0){

1399

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

1400

exitcode = EX_UNAVAILABLE;

1401

goto end;

1402

}

1403

1404

if(quit_now){

1405

goto end;

1406

}

1407

1408

/* Re-raise priviliges */

1409

errno = 0;

1410

ret = seteuid(0);

1411

if(ret == -1){

1412

perror("seteuid");

1413

}

1414

1415

#ifdef __linux__

1416

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1417

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

1418

ret = klogctl(8, NULL, 5);

1419

bool restore_loglevel = true;

1420

if(ret == -1){

1421

restore_loglevel = false;

1422

perror("klogctl");

1423

}

1424

#endif /* __linux__ */

1425

1426

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1427

if(sd < 0){

1428

perror("socket");

1429

exitcode = EX_OSERR;

1430

#ifdef __linux__

1431

if(restore_loglevel){

1432

ret = klogctl(7, NULL, 0);

1433

if(ret == -1){

1434

perror("klogctl");

1435

}

1436

}

1437

#endif /* __linux__ */

1438

/* Lower privileges */

1439

errno = 0;

1440

ret = seteuid(uid);

1441

if(ret == -1){

1442

perror("seteuid");

1443

}

1444

goto end;

1445

}

1446

strcpy(network.ifr_name, interface);

1447

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

1448

if(ret == -1){

1449

perror("ioctl SIOCGIFFLAGS");

1450

#ifdef __linux__

1451

if(restore_loglevel){

1452

ret = klogctl(7, NULL, 0);

1453

if(ret == -1){

1454

perror("klogctl");

1455

}

1456

}

1457

#endif /* __linux__ */

1458

exitcode = EX_OSERR;

1459

/* Lower privileges */

1460

errno = 0;

1461

ret = seteuid(uid);

1462

if(ret == -1){

1463

perror("seteuid");

1464

}

1465

goto end;

1466

}

1467

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

1468

network.ifr_flags |= IFF_UP;

1469

take_down_interface = true;

1470

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

1471

if(ret == -1){

1472

take_down_interface = false;

1473

perror("ioctl SIOCSIFFLAGS +IFF_UP");

1474

exitcode = EX_OSERR;

1475

#ifdef __linux__

1476

if(restore_loglevel){

1477

ret = klogctl(7, NULL, 0);

1478

if(ret == -1){

1479

perror("klogctl");

2152

perror_plus("sigaction");

2153

exitcode = EX_OSERR;

2154

goto end;

2155

}

2156

}

2157

2158

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

2159

if(mc.interfaces == NULL){

2160

struct dirent **direntries;

2161

/* Look for any good interfaces */

2162

ret = scandir(sys_class_net, &direntries, good_interface,

2163

alphasort);

2164

if(ret >= 1){

2165

/* Add all found interfaces to interfaces list */

2166

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

2167

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

2168

direntries[i]->d_name);

2169

if(ret_errno != 0){

2170

perror_plus("argz_add");

2171

continue;

2172

}

2173

if(debug){

2174

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

2175

direntries[i]->d_name);

2176

}

2177

}

2178

free(direntries);

2179

} else {

2180

free(direntries);

2181

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

2182

exitcode = EXIT_FAILURE;

2183

goto end;

2184

}

2185

}

2186

2187

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

2188

{

2189

char *interface = NULL;

2190

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

2191

interface))){

2192

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

2193

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

2194

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

2195

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

2196

interface);

2197

interface = NULL;

2198

while((interface = argz_next(mc.interfaces,

2199

mc.interfaces_size, interface))){

2200

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

2201

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

2202

interface);

2203

interface = NULL;

1480

2204

}

1481

2205

}

1482

#endif /* __linux__ */

1483

/* Lower privileges */

1484

errno = 0;

1485

ret = seteuid(uid);

1486

if(ret == -1){

1487

perror("seteuid");

1488

}

1489

goto end;

1490

}

1491

}

1492

/* sleep checking until interface is running */

1493

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

1494

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

1495

if(ret == -1){

1496

perror("ioctl SIOCGIFFLAGS");

1497

} else if(network.ifr_flags & IFF_RUNNING){

1498

2206

break;

1499

2207

}

1500

struct timespec sleeptime = { .tv_nsec = 250000000 };

1501

ret = nanosleep(&sleeptime, NULL);

1502

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

1503

perror("nanosleep");

1504

}

1505

}

1506

if(not take_down_interface){

1507

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

1508

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

1509

if(ret == -1){

1510

perror("close");

1511

}

1512

}

1513

#ifdef __linux__

1514

if(restore_loglevel){

1515

/* Restores kernel loglevel to default */

1516

ret = klogctl(7, NULL, 0);

1517

if(ret == -1){

1518

perror("klogctl");

1519

}

1520

}

1521

#endif /* __linux__ */

1522

/* Lower privileges */

1523

errno = 0;

1524

if(take_down_interface){

1525

/* Lower privileges */

1526

ret = seteuid(uid);

1527

if(ret == -1){

1528

perror("seteuid");

1529

}

1530

} else {

1531

/* Lower privileges permanently */

1532

ret = setuid(uid);

1533

if(ret == -1){

1534

perror("setuid");

1535

}

1536

}

2208

bool interface_was_up = interface_is_up(interface);

2209

ret = bring_up_interface(interface, delay);

2210

if(not interface_was_up){

2211

if(ret != 0){

2212

errno = ret;

2213

perror_plus("Failed to bring up interface");

2214

} else {

2215

ret_errno = argz_add(&interfaces_to_take_down,

2216

&interfaces_to_take_down_size,

2217

interface);

2218

}

2219

}

2220

}

2221

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

2222

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

2223

}

2224

}

2225

2226

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

2227

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

2228

if(debug){

2229

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

2230

mc.interfaces);

2231

}

2232

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

1537

2233

}

1538

2234

1539

2235

if(quit_now){

1540

2236

goto end;

1541

2237

}

1542

2238

1543

ret = init_gnutls_global(pubkey, seckey);

2239

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

1544

2240

if(ret == -1){

1545

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

2241

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

1546

2242

exitcode = EX_UNAVAILABLE;

1547

2243

goto end;

1548

2244

} else {

1553

2249

goto end;

1554

2250

}

1555

2251

2252

if(mkdtemp(tempdir) == NULL){

2253

perror_plus("mkdtemp");

2254

goto end;

2255

}

1556

2256

tempdir_created = true;

1557

if(mkdtemp(tempdir) == NULL){

1558

tempdir_created = false;

1559

perror("mkdtemp");

1560

goto end;

1561

}

1562

2257

1563

2258

if(quit_now){

1564

2259

goto end;

1565

2260

}

1566

2261

1567

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

1568

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

2262

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

2263

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

1569

2264

exitcode = EX_UNAVAILABLE;

1570

2265

goto end;

1571

2266

} else {

1580

2275

/* Connect directly, do not use Zeroconf */

1581

2276

/* (Mainly meant for debugging) */

1582

2277

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

2278

1583

2279

if(address == NULL){

1584

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

2280

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

1585

2281

exitcode = EX_USAGE;

1586

2282

goto end;

1587

2283

}

1590

2286

goto end;

1591

2287

}

1592

2288

1593

uint16_t port;

2289

in_port_t port;

1594

2290

errno = 0;

1595

2291

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

1596

2292

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

1597

or tmpmax != (uint16_t)tmpmax){

1598

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

2293

or tmpmax != (in_port_t)tmpmax){

2294

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

1599

2295

exitcode = EX_USAGE;

1600

2296

goto end;

1601

2297

}

1602

2298

1603

2299

if(quit_now){

1604

2300

goto end;

1605

2301

}

1606

2302

1607

port = (uint16_t)tmpmax;

2303

port = (in_port_t)tmpmax;

1608

2304

*address = '\0';

1609

address = connect_to;

1610

2305

/* Colon in address indicates IPv6 */

1611

2306

int af;

1612

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

2307

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

1613

2308

af = AF_INET6;

2309

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

2310

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

2311

{

2312

connect_to++;

2313

address[-1] = '\0';

2314

}

1614

2315

} else {

1615

2316

af = AF_INET;

1616

2317

}

2318

address = connect_to;

1617

2319

1618

2320

if(quit_now){

1619

2321

goto end;

1620

2322

}

1621

2323

1622

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

1623

if(ret < 0){

1624

switch(errno){

1625

case ENETUNREACH:

1626

case EHOSTDOWN:

1627

case EHOSTUNREACH:

1628

exitcode = EX_NOHOST;

1629

break;

1630

case EINVAL:

1631

exitcode = EX_USAGE;

1632

break;

1633

case EIO:

1634

exitcode = EX_IOERR;

1635

break;

1636

case EPROTO:

1637

exitcode = EX_PROTOCOL;

1638

break;

1639

default:

1640

exitcode = EX_OSERR;

1641

break;

1642

}

1643

} else {

2324

while(not quit_now){

2325

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

2326

&mc);

2327

if(quit_now or ret == 0){

2328

break;

2329

}

2330

if(debug){

2331

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

2332

(int)retry_interval);

2333

}

2334

sleep((unsigned int)retry_interval);

2335

}

2336

2337

if (not quit_now){

1644

2338

exitcode = EXIT_SUCCESS;

1645

2339

}

2340

1646

2341

goto end;

1647

2342

}

1648

2343

1660

2355

config.publish_domain = 0;

1661

2356

1662

2357

/* Allocate a new server */

1663

mc.server = avahi_server_new(avahi_simple_poll_get

1664

(mc.simple_poll), &config, NULL,

1665

NULL, &error);

2358

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2359

&config, NULL, NULL, &ret_errno);

1666

2360

1667

2361

/* Free the Avahi configuration data */

1668

2362

avahi_server_config_free(&config);

1670

2364

1671

2365

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

1672

2366

if(mc.server == NULL){

1673

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

1674

avahi_strerror(error));

2367

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

2368

avahi_strerror(ret_errno));

1675

2369

exitcode = EX_UNAVAILABLE;

1676

2370

goto end;

1677

2371

}

1683

2377

/* Create the Avahi service browser */

1684

2378

sb = avahi_s_service_browser_new(mc.server, if_index,

1685

2379

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1686

NULL, 0, browse_callback, NULL);

2380

NULL, 0, browse_callback,

2381

(void *)&mc);

1687

2382

if(sb == NULL){

1688

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

1689

avahi_strerror(avahi_server_errno(mc.server)));

2383

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

2384

avahi_strerror(avahi_server_errno(mc.server)));

1690

2385

exitcode = EX_UNAVAILABLE;

1691

2386

goto end;

1692

2387

}

1698

2393

/* Run the main loop */

1699

2394

1700

2395

if(debug){

1701

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

1702

}

1703

1704

avahi_simple_poll_loop(mc.simple_poll);

2396

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

2397

}

2398

2399

ret = avahi_loop_with_timeout(simple_poll,

2400

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

2401

if(debug){

2402

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

2403

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

2404

}

1705

2405

1706

2406

end:

1707

2407

1708

2408

if(debug){

1709

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

2409

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

1710

2410

}

1711

2411

1712

2412

/* Cleanup things */

2413

free(mc.interfaces);

2414

1713

2415

if(sb != NULL)

1714

2416

avahi_s_service_browser_free(sb);

1715

2417

1716

2418

if(mc.server != NULL)

1717

2419

avahi_server_free(mc.server);

1718

2420

1719

if(mc.simple_poll != NULL)

1720

avahi_simple_poll_free(mc.simple_poll);

2421

if(simple_poll != NULL)

2422

avahi_simple_poll_free(simple_poll);

1721

2423

1722

2424

if(gnutls_initialized){

1723

2425

gnutls_certificate_free_credentials(mc.cred);

1729

2431

gpgme_release(mc.ctx);

1730

2432

}

1731

2433

1732

/* Take down the network interface */

1733

if(take_down_interface){

1734

/* Re-raise priviliges */

1735

errno = 0;

1736

ret = seteuid(0);

1737

if(ret == -1){

1738

perror("seteuid");

2434

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

2435

has seen */

2436

if(mc.current_server != NULL){

2437

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

2438

while(mc.current_server != NULL){

2439

server *next = mc.current_server->next;

2440

free(mc.current_server);

2441

mc.current_server = next;

1739

2442

}

1740

if(geteuid() == 0){

1741

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

1742

if(ret == -1){

1743

perror("ioctl SIOCGIFFLAGS");

1744

} else if(network.ifr_flags & IFF_UP) {

1745

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

1746

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

1747

if(ret == -1){

1748

perror("ioctl SIOCSIFFLAGS -IFF_UP");

2443

}

2444

2445

/* Re-raise priviliges */

2446

{

2447

raise_privileges();

2448

2449

/* Run network hooks */

2450

run_network_hooks("stop", interfaces_hooks != NULL ?

2451

interfaces_hooks : "", delay);

2452

2453

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

2454

{

2455

char *interface = NULL;

2456

while((interface=argz_next(interfaces_to_take_down,

2457

interfaces_to_take_down_size,

2458

interface))){

2459

ret_errno = take_down_interface(interface);

2460

if(ret_errno != 0){

2461

errno = ret_errno;

2462

perror_plus("Failed to take down interface");

1749

2463

}

1750

2464

}

1751

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

1752

if(ret == -1){

1753

perror("close");

1754

}

1755

/* Lower privileges permanently */

1756

errno = 0;

1757

ret = setuid(uid);

1758

if(ret == -1){

1759

perror("setuid");

2465

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

2466

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

2467

" down\n");

1760

2468

}

1761

2469

}

2470

2471

lower_privileges_permanently();

1762

2472

}

1763

2473

1764

/* Removes the temp directory used by GPGME */

2474

free(interfaces_to_take_down);

2475

free(interfaces_hooks);

2476

2477

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

1765

2478

if(tempdir_created){

1766

DIR *d;

1767

struct dirent *direntry;

1768

d = opendir(tempdir);

1769

if(d == NULL){

1770

if(errno != ENOENT){

1771

perror("opendir");

1772

}

1773

} else {

1774

while(true){

1775

direntry = readdir(d);

1776

if(direntry == NULL){

1777

break;

1778

}

1779

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

1780

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

1781

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

1782

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

1783

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

1784

continue;

1785

}

2479

struct dirent **direntries = NULL;

2480

struct dirent *direntry = NULL;

2481

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

2482

alphasort);

2483

if (numentries > 0){

2484

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

2485

direntry = direntries[i];

1786

2486

char *fullname = NULL;

1787

2487

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

1788

2488

direntry->d_name);

1789

2489

if(ret < 0){

1790

perror("asprintf");

2490

perror_plus("asprintf");

1791

2491

continue;

1792

2492

}

1793

2493

ret = remove(fullname);

1794

2494

if(ret == -1){

1795

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

1796

strerror(errno));

2495

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

2496

strerror(errno));

1797

2497

}

1798

2498

free(fullname);

1799

2499

}

1800

closedir(d);

2500

}

2501

2502

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

2503

free(direntries);

2504

if (numentries == -1){

2505

perror_plus("scandir");

1801

2506

}

1802

2507

ret = rmdir(tempdir);

1803

2508

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

1804

perror("rmdir");

2509

perror_plus("rmdir");

1805

2510

}

1806

2511

}

1807

2512

1812

2517

&old_sigterm_action,

1813

2518

NULL));

1814

2519

if(ret == -1){

1815

perror("sigaction");

2520

perror_plus("sigaction");

1816

2521

}

1817

2522

do {

1818

2523

ret = raise(signal_received);

1819

2524

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

1820

2525

if(ret != 0){

1821

perror("raise");

2526

perror_plus("raise");

1822

2527

abort();

1823

2528

}

1824

2529

TEMP_FAILURE_RETRY(pause());