/mandos/release : revision 237.7.148

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

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program_invocation_short_name */

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

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

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SIOCSIFFLAGS, if_indextoname(),

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*/

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

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

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setgid(), pause() */

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

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

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#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() */

107

114

init_gnutls_session(),

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115

GNUTLS_* */

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116

#include <gnutls/openpgp.h>

110

/* gnutls_certificate_set_openpgp_key_file(),

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GNUTLS_OPENPGP_FMT_BASE64 */

117

/* gnutls_certificate_set_openpgp_key_file(),

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GNUTLS_OPENPGP_FMT_BASE64 */

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/* GPGME */

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121

#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

126

134

bool debug = false;

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135

static const char mandos_protocol_version[] = "1";

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136

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;

150

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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156

typedef struct {

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161

gnutls_dh_params_t dh_params;

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162

const char *priority;

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163

gpgme_ctx_t ctx;

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server *current_server;

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} mandos_context;

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166

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

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.current_server = NULL };

148

172

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173

sig_atomic_t quit_now = 0;

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174

int signal_received = 0;

151

175

176

/* Function to use when printing errors */

177

void perror_plus(const char *print_text){

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int e = errno;

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

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program_invocation_short_name);

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errno = e;

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perror(print_text);

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}

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

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

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va_list ap;

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va_start (ap, format);

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190

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

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program_invocation_short_name));

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

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}

194

152

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/*

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196

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

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

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198

* "buffer_length" is how much is already used.

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199

*/

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size_t incbuffer(char **buffer, size_t buffer_length,

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size_t buffer_capacity){

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size_t buffer_capacity){

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202

if(buffer_length + BUFFER_SIZE > buffer_capacity){

160

203

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

161

204

if(buffer == NULL){

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209

return buffer_capacity;

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210

}

168

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

213

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

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int af){

215

int ret;

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

217

if(new_server == NULL){

218

perror_plus("malloc");

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return false;

220

}

221

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

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.port = port,

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.if_index = if_index,

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.af = af };

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if(new_server->ip == NULL){

226

perror_plus("strdup");

227

return false;

228

}

229

/* Special case of first server */

230

if (mc.current_server == NULL){

231

new_server->next = new_server;

232

new_server->prev = new_server;

233

mc.current_server = new_server;

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

235

} else {

236

new_server->next = mc.current_server;

237

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

238

new_server->prev->next = new_server;

239

mc.current_server->prev = new_server;

240

}

241

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

242

if(ret == -1){

243

perror_plus("clock_gettime");

244

return false;

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}

246

return true;

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}

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/*

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* Initialize GPGME.

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251

*/

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static bool init_gpgme(const char *seckey,

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const char *pubkey, const char *tempdir){

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

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const char *tempdir){

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gpgme_error_t rc;

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gpgme_engine_info_t engine_info;

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

187

267

if(fd == -1){

188

perror("open");

268

perror_plus("open");

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return false;

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270

}

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rc = gpgme_data_new_from_fd(&pgp_data, fd);

193

273

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));

274

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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276

return false;

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277

}

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rc = gpgme_op_import(mc.ctx, pgp_data);

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280

if(rc != GPG_ERR_NO_ERROR){

201

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

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gpgme_strsource(rc), gpgme_strerror(rc));

281

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

282

gpgme_strsource(rc), gpgme_strerror(rc));

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283

return false;

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284

}

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285

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

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287

if(ret == -1){

208

perror("close");

288

perror_plus("close");

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}

210

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gpgme_data_release(pgp_data);

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return true;

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292

}

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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){

222

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

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gpgme_strsource(rc), gpgme_strerror(rc));

302

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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}

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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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308

rc = gpgme_get_engine_info(&engine_info);

229

309

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));

310

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

311

gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

233

313

}

234

314

while(engine_info != NULL){

240

320

engine_info = engine_info->next;

241

321

}

242

322

if(engine_info == NULL){

243

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

323

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

324

tempdir);

244

325

return false;

245

326

}

246

327

247

328

/* Create new GPGME "context" */

248

329

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

249

330

if(rc != GPG_ERR_NO_ERROR){

250

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

251

gpgme_strsource(rc), gpgme_strerror(rc));

331

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

332

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

333

gpgme_strerror(rc));

252

334

return false;

253

335

}

254

336

273

355

ssize_t plaintext_length = 0;

274

356

275

357

if(debug){

276

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

358

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

277

359

}

278

360

279

361

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

280

362

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

281

363

0);

282

364

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));

365

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

366

gpgme_strsource(rc), gpgme_strerror(rc));

285

367

return -1;

286

368

}

287

369

288

370

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

289

371

rc = gpgme_data_new(&dh_plain);

290

372

if(rc != GPG_ERR_NO_ERROR){

291

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

292

gpgme_strsource(rc), gpgme_strerror(rc));

373

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

374

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

375

gpgme_strsource(rc), gpgme_strerror(rc));

293

376

gpgme_data_release(dh_crypto);

294

377

return -1;

295

378

}

298

381

data buffer */

299

382

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

300

383

if(rc != GPG_ERR_NO_ERROR){

301

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

302

gpgme_strsource(rc), gpgme_strerror(rc));

384

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

385

gpgme_strsource(rc), gpgme_strerror(rc));

303

386

plaintext_length = -1;

304

387

if(debug){

305

388

gpgme_decrypt_result_t result;

306

389

result = gpgme_op_decrypt_result(mc.ctx);

307

390

if(result == NULL){

308

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

391

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

309

392

} 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);

393

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

394

result->unsupported_algorithm);

395

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

396

result->wrong_key_usage);

314

397

if(result->file_name != NULL){

315

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

398

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

316

399

}

317

400

gpgme_recipient_t recipient;

318

401

recipient = result->recipients;

319

402

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");

403

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

404

gpgme_pubkey_algo_name

405

(recipient->pubkey_algo));

406

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

407

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

408

recipient->status == GPG_ERR_NO_SECKEY

409

? "No" : "Yes");

326

410

recipient = recipient->next;

327

411

}

328

412

}

331

415

}

332

416

333

417

if(debug){

334

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

418

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

335

419

}

336

420

337

421

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

338

422

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

339

perror("gpgme_data_seek");

423

perror_plus("gpgme_data_seek");

340

424

plaintext_length = -1;

341

425

goto decrypt_end;

342

426

}

344

428

*plaintext = NULL;

345

429

while(true){

346

430

plaintext_capacity = incbuffer(plaintext,

347

(size_t)plaintext_length,

348

plaintext_capacity);

431

(size_t)plaintext_length,

432

plaintext_capacity);

349

433

if(plaintext_capacity == 0){

350

perror("incbuffer");

351

plaintext_length = -1;

352

goto decrypt_end;

434

perror_plus("incbuffer");

435

plaintext_length = -1;

436

goto decrypt_end;

353

437

}

354

438

355

439

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

360

444

break;

361

445

}

362

446

if(ret < 0){

363

perror("gpgme_data_read");

447

perror_plus("gpgme_data_read");

364

448

plaintext_length = -1;

365

449

goto decrypt_end;

366

450

}

368

452

}

369

453

370

454

if(debug){

371

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

455

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

372

456

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

373

457

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

374

458

}

386

470

}

387

471

388

472

static const char * safer_gnutls_strerror(int value){

389

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

390

-Wunreachable-code */

473

const char *ret = gnutls_strerror(value);

391

474

if(ret == NULL)

392

475

ret = "(unknown)";

393

476

return ret;

396

479

/* GnuTLS log function callback */

397

480

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

398

481

const char* string){

399

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

482

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

400

483

}

401

484

402

485

static int init_gnutls_global(const char *pubkeyfilename,

404

487

int ret;

405

488

406

489

if(debug){

407

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

490

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

408

491

}

409

492

410

493

ret = gnutls_global_init();

411

494

if(ret != GNUTLS_E_SUCCESS){

412

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

413

safer_gnutls_strerror(ret));

495

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

496

safer_gnutls_strerror(ret));

414

497

return -1;

415

498

}

416

499

423

506

}

424

507

425

508

/* OpenPGP credentials */

426

gnutls_certificate_allocate_credentials(&mc.cred);

509

ret = gnutls_certificate_allocate_credentials(&mc.cred);

427

510

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));

511

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

512

safer_gnutls_strerror(ret));

433

513

gnutls_global_deinit();

434

514

return -1;

435

515

}

436

516

437

517

if(debug){

438

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

439

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

440

seckeyfilename);

518

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

519

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

520

pubkeyfilename,

521

seckeyfilename);

441

522

}

442

523

443

524

ret = gnutls_certificate_set_openpgp_key_file

444

525

(mc.cred, pubkeyfilename, seckeyfilename,

445

526

GNUTLS_OPENPGP_FMT_BASE64);

446

527

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));

528

fprintf_plus(stderr,

529

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

530

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

531

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

532

safer_gnutls_strerror(ret));

452

533

goto globalfail;

453

534

}

454

535

455

536

/* GnuTLS server initialization */

456

537

ret = gnutls_dh_params_init(&mc.dh_params);

457

538

if(ret != GNUTLS_E_SUCCESS){

458

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

459

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

539

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

540

" initialization: %s\n",

541

safer_gnutls_strerror(ret));

460

542

goto globalfail;

461

543

}

462

544

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

463

545

if(ret != GNUTLS_E_SUCCESS){

464

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

465

safer_gnutls_strerror(ret));

546

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

547

safer_gnutls_strerror(ret));

466

548

goto globalfail;

467

549

}

468

550

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

{

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

}

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

}

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

626

int af){

544

627

int ret, tcp_sd = -1;

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

}

582

665

}

583

666

584

667

if(debug){

585

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

586

"\n", ip, port);

668

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

669

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

587

670

}

588

671

589

672

tcp_sd = socket(pf, SOCK_STREAM, 0);

590

673

if(tcp_sd < 0){

591

674

int e = errno;

592

perror("socket");

675

perror_plus("socket");

593

676

errno = e;

594

677

goto mandos_end;

595

678

}

609

692

}

610

693

if(ret < 0 ){

611

694

int e = errno;

612

perror("inet_pton");

695

perror_plus("inet_pton");

613

696

errno = e;

614

697

goto mandos_end;

615

698

}

616

699

if(ret == 0){

617

700

int e = errno;

618

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

701

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

619

702

errno = e;

620

703

goto mandos_end;

621

704

}

622

705

if(af == AF_INET6){

623

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

624

-Wconversion and

625

-Wunreachable-code */

626

706

to.in6.sin6_port = htons(port);

627

707

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

628

708

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

629

-Wunreachable-code*/

709

-Wunreachable-code*/

630

710

if(if_index == AVAHI_IF_UNSPEC){

631

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

632

" without a network interface\n");

711

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

712

" incomplete without a network interface\n");

633

713

errno = EINVAL;

634

714

goto mandos_end;

635

715

}

651

731

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

652

732

char interface[IF_NAMESIZE];

653

733

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

654

perror("if_indextoname");

734

perror_plus("if_indextoname");

655

735

} else {

656

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

657

ip, interface, port);

736

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

737

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

658

738

}

659

739

} else {

660

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

661

port);

740

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

741

ip, (uintmax_t)port);

662

742

}

663

743

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

664

744

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

671

751

sizeof(addrstr));

672

752

}

673

753

if(pcret == NULL){

674

perror("inet_ntop");

754

perror_plus("inet_ntop");

675

755

} else {

676

756

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

677

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

757

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

678

758

}

679

759

}

680

760

}

692

772

if(ret < 0){

693

773

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

694

774

int e = errno;

695

perror("connect");

775

perror_plus("connect");

696

776

errno = e;

697

777

}

698

778

goto mandos_end;

708

788

while(true){

709

789

size_t out_size = strlen(out);

710

790

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

711

out_size - written));

791

out_size - written));

712

792

if(ret == -1){

713

793

int e = errno;

714

perror("write");

794

perror_plus("write");

715

795

errno = e;

716

796

goto mandos_end;

717

797

}

734

814

}

735

815

736

816

if(debug){

737

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

817

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

738

818

}

739

819

740

820

if(quit_now){

742

822

goto mandos_end;

743

823

}

744

824

745

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

825

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

826

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

827

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

828

gnutls_transport_set_ptr(session,

829

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

746

830

747

831

if(quit_now){

748

832

errno = EINTR;

759

843

760

844

if(ret != GNUTLS_E_SUCCESS){

761

845

if(debug){

762

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

846

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

763

847

gnutls_perror(ret);

764

848

}

765

849

errno = EPROTO;

769

853

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

770

854

771

855

if(debug){

772

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

773

ip);

856

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

857

" %s\n", ip);

774

858

}

775

859

776

860

while(true){

781

865

}

782

866

783

867

buffer_capacity = incbuffer(&buffer, buffer_length,

784

buffer_capacity);

868

buffer_capacity);

785

869

if(buffer_capacity == 0){

786

870

int e = errno;

787

perror("incbuffer");

871

perror_plus("incbuffer");

788

872

errno = e;

789

873

goto mandos_end;

790

874

}

814

898

}

815

899

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

816

900

if(ret < 0){

817

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

901

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

902

"***\n");

818

903

gnutls_perror(ret);

819

904

errno = EPROTO;

820

905

goto mandos_end;

821

906

}

822

907

break;

823

908

default:

824

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

825

" encrypted session with Mandos server\n");

909

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

910

" encrypted session with Mandos server\n");

826

911

gnutls_bye(session, GNUTLS_SHUT_RDWR);

827

912

errno = EIO;

828

913

goto mandos_end;

833

918

}

834

919

835

920

if(debug){

836

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

921

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

837

922

}

838

923

839

924

if(quit_now){

851

936

852

937

if(buffer_length > 0){

853

938

ssize_t decrypted_buffer_size;

854

decrypted_buffer_size = pgp_packet_decrypt(buffer,

855

buffer_length,

939

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

856

940

&decrypted_buffer);

857

941

if(decrypted_buffer_size >= 0){

858

942

869

953

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

870

954

int e = errno;

871

955

if(debug){

872

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

873

strerror(errno));

956

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

957

strerror(errno));

874

958

}

875

959

errno = e;

876

960

goto mandos_end;

895

979

if(e == 0){

896

980

e = errno;

897

981

}

898

perror("close");

982

perror_plus("close");

899

983

}

900

984

gnutls_deinit(session);

985

errno = e;

901

986

if(quit_now){

902

e = EINTR;

987

errno = EINTR;

903

988

retval = -1;

904

989

}

905

errno = e;

906

990

}

907

991

return retval;

908

992

}

921

1005

AVAHI_GCC_UNUSED AvahiLookupResultFlags

922

1006

flags,

923

1007

AVAHI_GCC_UNUSED void* userdata){

924

assert(r);

1008

if(r == NULL){

1009

return;

1010

}

925

1011

926

1012

/* Called whenever a service has been resolved successfully or

927

1013

timed out */

933

1019

switch(event){

934

1020

default:

935

1021

case AVAHI_RESOLVER_FAILURE:

936

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

937

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

938

avahi_strerror(avahi_server_errno(mc.server)));

1022

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

1023

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

1024

domain,

1025

avahi_strerror(avahi_server_errno(mc.server)));

939

1026

break;

940

1027

941

1028

case AVAHI_RESOLVER_FOUND:

943

1030

char ip[AVAHI_ADDRESS_STR_MAX];

944

1031

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

945

1032

if(debug){

946

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

947

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

948

ip, (intmax_t)interface, port);

1033

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

1034

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

1035

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

949

1036

}

950

int ret = start_mandos_communication(ip, port, interface,

1037

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

1038

interface,

951

1039

avahi_proto_to_af(proto));

952

1040

if(ret == 0){

953

1041

avahi_simple_poll_quit(mc.simple_poll);

1042

} else {

1043

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

1044

avahi_proto_to_af(proto))){

1045

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

1046

" list\n", name);

1047

}

954

1048

}

955

1049

}

956

1050

}

967

1061

AVAHI_GCC_UNUSED AvahiLookupResultFlags

968

1062

flags,

969

1063

AVAHI_GCC_UNUSED void* userdata){

970

assert(b);

1064

if(b == NULL){

1065

return;

1066

}

971

1067

972

1068

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

973

1069

is removed from the LAN */

980

1076

default:

981

1077

case AVAHI_BROWSER_FAILURE:

982

1078

983

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

984

avahi_strerror(avahi_server_errno(mc.server)));

1079

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

1080

avahi_strerror(avahi_server_errno(mc.server)));

985

1081

avahi_simple_poll_quit(mc.simple_poll);

986

1082

return;

987

1083

994

1090

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

995

1091

name, type, domain, protocol, 0,

996

1092

resolve_callback, NULL) == NULL)

997

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

998

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

1093

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

1094

" %s\n", name,

1095

avahi_strerror(avahi_server_errno(mc.server)));

999

1096

break;

1000

1097

1001

1098

case AVAHI_BROWSER_REMOVE:

1004

1101

case AVAHI_BROWSER_ALL_FOR_NOW:

1005

1102

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1006

1103

if(debug){

1007

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

1104

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

1105

" searching...\n");

1008

1106

}

1009

1107

break;

1010

1108

}

1011

1109

}

1012

1110

1013

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

1111

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

1014

1112

static void handle_sigterm(int sig){

1015

1113

if(quit_now){

1016

1114

return;

1018

1116

quit_now = 1;

1019

1117

signal_received = sig;

1020

1118

int old_errno = errno;

1119

/* set main loop to exit */

1021

1120

if(mc.simple_poll != NULL){

1022

1121

avahi_simple_poll_quit(mc.simple_poll);

1023

1122

}

1024

1123

errno = old_errno;

1025

1124

}

1026

1125

1126

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

1127

int ret;

1128

error_t ret_errno;

1129

1130

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

1131

if(s < 0){

1132

ret_errno = errno;

1133

perror_plus("socket");

1134

errno = ret_errno;

1135

return false;

1136

}

1137

strcpy(ifr->ifr_name, ifname);

1138

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1139

if(ret == -1){

1140

if(debug){

1141

ret_errno = errno;

1142

perror_plus("ioctl SIOCGIFFLAGS");

1143

errno = ret_errno;

1144

}

1145

return false;

1146

}

1147

return true;

1148

}

1149

1150

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

1151

1152

/* Reject the loopback device */

1153

if(ifr->ifr_flags & IFF_LOOPBACK){

1154

if(debug){

1155

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

1156

ifname);

1157

}

1158

return false;

1159

}

1160

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

1161

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

1162

if(debug){

1163

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

1164

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

1165

}

1166

return true;

1167

}

1168

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

1169

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

1170

if(debug){

1171

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1172

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

1173

}

1174

return false;

1175

}

1176

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

1177

if(ifr->ifr_flags & IFF_NOARP){

1178

if(debug){

1179

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

1180

ifname);

1181

}

1182

return false;

1183

}

1184

1185

/* Accept this device */

1186

if(debug){

1187

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

1188

}

1189

return true;

1190

}

1191

1027

1192

/*

1028

1193

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

1029

1194

* corresponds to an acceptable network device.

1030

1195

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

1031

1196

*/

1032

1197

int good_interface(const struct dirent *if_entry){

1033

ssize_t ssret;

1034

char *flagname = NULL;

1035

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

1036

if_entry->d_name);

1037

if(ret < 0){

1038

perror("asprintf");

1039

return 0;

1040

}

1041

1198

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

1042

1199

return 0;

1043

1200

}

1044

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

1045

if(flags_fd == -1){

1046

perror("open");

1047

return 0;

1048

}

1049

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

1050

/* read line from flags_fd */

1051

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

1052

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

1053

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

1054

if(flagstring == NULL){

1055

perror("malloc");

1056

close(flags_fd);

1057

return 0;

1058

}

1059

while(to_read > 0){

1060

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

1061

(size_t)to_read));

1062

if(ssret == -1){

1063

perror("read");

1064

free(flagstring);

1065

close(flags_fd);

1066

return 0;

1067

}

1068

to_read -= ssret;

1069

if(ssret == 0){

1201

1202

struct ifreq ifr;

1203

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

1204

if(debug){

1205

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

1206

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

1207

}

1208

return 0;

1209

}

1210

1211

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

1212

return 0;

1213

}

1214

return 1;

1215

}

1216

1217

/*

1218

* This function determines if a network interface is up.

1219

*/

1220

bool interface_is_up(const char *interface){

1221

struct ifreq ifr;

1222

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

1223

if(debug){

1224

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

1225

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

1226

}

1227

return false;

1228

}

1229

1230

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

1231

}

1232

1233

/*

1234

* This function determines if a network interface is running

1235

*/

1236

bool interface_is_running(const char *interface){

1237

struct ifreq ifr;

1238

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

1239

if(debug){

1240

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

1241

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

1242

}

1243

return false;

1244

}

1245

1246

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

1247

}

1248

1249

int notdotentries(const struct dirent *direntry){

1250

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

1251

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

1252

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

1253

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

1254

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

1255

return 0;

1256

}

1257

return 1;

1258

}

1259

1260

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

1261

int runnable_hook(const struct dirent *direntry){

1262

int ret;

1263

size_t sret;

1264

struct stat st;

1265

1266

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

1267

/* Empty name? */

1268

return 0;

1269

}

1270

1271

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

1272

"abcdefghijklmnopqrstuvwxyz"

1273

"0123456789"

1274

"_-");

1275

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

1276

/* Contains non-allowed characters */

1277

if(debug){

1278

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

1279

direntry->d_name);

1280

}

1281

return 0;

1282

}

1283

1284

char *fullname = NULL;

1285

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

1286

if(ret < 0){

1287

perror_plus("asprintf");

1288

return 0;

1289

}

1290

1291

ret = stat(fullname, &st);

1292

if(ret == -1){

1293

if(debug){

1294

perror_plus("Could not stat hook");

1295

}

1296

return 0;

1297

}

1298

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

1299

/* Not a regular file */

1300

if(debug){

1301

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

1302

direntry->d_name);

1303

}

1304

return 0;

1305

}

1306

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

1307

/* Not executable */

1308

if(debug){

1309

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

1310

direntry->d_name);

1311

}

1312

return 0;

1313

}

1314

if(debug){

1315

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

1316

direntry->d_name);

1317

}

1318

return 1;

1319

}

1320

1321

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1322

int ret;

1323

struct timespec now;

1324

struct timespec waited_time;

1325

intmax_t block_time;

1326

1327

while(true){

1328

if(mc.current_server == NULL){

1329

if (debug){

1330

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

1331

" No timeout!\n");

1332

}

1333

ret = avahi_simple_poll_iterate(s, -1);

1334

} else {

1335

if (debug){

1336

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

1337

" it, or wait\n");

1338

}

1339

/* the current time */

1340

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1341

if(ret == -1){

1342

perror_plus("clock_gettime");

1343

return -1;

1344

}

1345

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

1346

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

1347

waited_time.tv_sec = (now.tv_sec

1348

- mc.current_server->last_seen.tv_sec);

1349

waited_time.tv_nsec = (now.tv_nsec

1350

- mc.current_server->last_seen.tv_nsec);

1351

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

1352

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

1353

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

1354

block_time = ((retry_interval

1355

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

1356

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

1357

1358

if (debug){

1359

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

1360

block_time);

1361

}

1362

1363

if(block_time <= 0){

1364

ret = start_mandos_communication(mc.current_server->ip,

1365

mc.current_server->port,

1366

mc.current_server->if_index,

1367

mc.current_server->af);

1368

if(ret == 0){

1369

avahi_simple_poll_quit(mc.simple_poll);

1370

return 0;

1371

}

1372

ret = clock_gettime(CLOCK_MONOTONIC,

1373

&mc.current_server->last_seen);

1374

if(ret == -1){

1375

perror_plus("clock_gettime");

1376

return -1;

1377

}

1378

mc.current_server = mc.current_server->next;

1379

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

1380

servers, but don't block */

1381

}

1382

1383

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

1384

}

1385

if(ret != 0){

1386

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

1387

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

1388

}

1389

}

1390

}

1391

}

1392

1393

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

1394

error_t raise_privileges(void){

1395

error_t old_errno = errno;

1396

error_t ret_errno = 0;

1397

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

1398

ret_errno = errno;

1399

perror_plus("seteuid");

1400

}

1401

errno = old_errno;

1402

return ret_errno;

1403

}

1404

1405

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

1406

error_t raise_privileges_permanently(void){

1407

error_t old_errno = errno;

1408

error_t ret_errno = raise_privileges();

1409

if(ret_errno != 0){

1410

errno = old_errno;

1411

return ret_errno;

1412

}

1413

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

1414

ret_errno = errno;

1415

perror_plus("seteuid");

1416

}

1417

errno = old_errno;

1418

return ret_errno;

1419

}

1420

1421

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

1422

error_t lower_privileges(void){

1423

error_t old_errno = errno;

1424

error_t ret_errno = 0;

1425

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

1426

ret_errno = errno;

1427

perror_plus("seteuid");

1428

}

1429

errno = old_errno;

1430

return ret_errno;

1431

}

1432

1433

/* Lower privileges permanently */

1434

error_t lower_privileges_permanently(void){

1435

error_t old_errno = errno;

1436

error_t ret_errno = 0;

1437

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

1438

ret_errno = errno;

1439

perror_plus("setuid");

1440

}

1441

errno = old_errno;

1442

return ret_errno;

1443

}

1444

1445

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

1446

const float delay){

1447

struct dirent **direntries;

1448

struct dirent *direntry;

1449

int ret;

1450

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

1451

alphasort);

1452

if(numhooks == -1){

1453

if(errno == ENOENT){

1454

if(debug){

1455

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

1456

" found\n", hookdir);

1457

}

1458

} else {

1459

perror_plus("scandir");

1460

}

1461

} else {

1462

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

1463

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

1464

direntry = direntries[i];

1465

char *fullname = NULL;

1466

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

1467

if(ret < 0){

1468

perror_plus("asprintf");

1469

continue;

1470

}

1471

if(debug){

1472

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

1473

direntry->d_name);

1474

}

1475

pid_t hook_pid = fork();

1476

if(hook_pid == 0){

1477

/* Child */

1478

/* Raise privileges */

1479

raise_privileges_permanently();

1480

/* Set group */

1481

errno = 0;

1482

ret = setgid(0);

1483

if(ret == -1){

1484

perror_plus("setgid");

1485

}

1486

/* Reset supplementary groups */

1487

errno = 0;

1488

ret = setgroups(0, NULL);

1489

if(ret == -1){

1490

perror_plus("setgroups");

1491

}

1492

dup2(devnull, STDIN_FILENO);

1493

close(devnull);

1494

dup2(STDERR_FILENO, STDOUT_FILENO);

1495

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

1496

if(ret == -1){

1497

perror_plus("setenv");

1498

_exit(EX_OSERR);

1499

}

1500

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

1501

if(ret == -1){

1502

perror_plus("setenv");

1503

_exit(EX_OSERR);

1504

}

1505

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

1506

if(ret == -1){

1507

perror_plus("setenv");

1508

_exit(EX_OSERR);

1509

}

1510

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

1511

if(ret == -1){

1512

perror_plus("setenv");

1513

_exit(EX_OSERR);

1514

}

1515

char *delaystring;

1516

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

1517

if(ret == -1){

1518

perror_plus("asprintf");

1519

_exit(EX_OSERR);

1520

}

1521

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

1522

if(ret == -1){

1523

free(delaystring);

1524

perror_plus("setenv");

1525

_exit(EX_OSERR);

1526

}

1527

free(delaystring);

1528

if(connect_to != NULL){

1529

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

1530

if(ret == -1){

1531

perror_plus("setenv");

1532

_exit(EX_OSERR);

1533

}

1534

}

1535

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

1536

perror_plus("execl");

1537

_exit(EXIT_FAILURE);

1538

}

1539

} else {

1540

int status;

1541

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

1542

perror_plus("waitpid");

1543

free(fullname);

1544

continue;

1545

}

1546

if(WIFEXITED(status)){

1547

if(WEXITSTATUS(status) != 0){

1548

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

1549

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

1550

WEXITSTATUS(status));

1551

free(fullname);

1552

continue;

1553

}

1554

} else if(WIFSIGNALED(status)){

1555

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

1556

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

1557

WTERMSIG(status));

1558

free(fullname);

1559

continue;

1560

} else {

1561

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

1562

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

1563

free(fullname);

1564

continue;

1565

}

1566

}

1567

free(fullname);

1568

if(debug){

1569

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

1570

direntry->d_name);

1571

}

1572

}

1573

close(devnull);

1574

}

1575

return true;

1576

}

1577

1578

error_t bring_up_interface(const char *const interface,

1579

const float delay){

1580

int sd = -1;

1581

error_t old_errno = errno;

1582

error_t ret_errno = 0;

1583

int ret, ret_setflags;

1584

struct ifreq network;

1585

unsigned int if_index = if_nametoindex(interface);

1586

if(if_index == 0){

1587

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

1588

errno = old_errno;

1589

return ENXIO;

1590

}

1591

1592

if(quit_now){

1593

errno = old_errno;

1594

return EINTR;

1595

}

1596

1597

if(not interface_is_up(interface)){

1598

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

1599

ret_errno = errno;

1600

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

1601

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

1602

return ret_errno;

1603

}

1604

network.ifr_flags |= IFF_UP;

1605

1606

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1607

if(sd < 0){

1608

ret_errno = errno;

1609

perror_plus("socket");

1610

errno = old_errno;

1611

return ret_errno;

1612

}

1613

1614

if(quit_now){

1615

close(sd);

1616

errno = old_errno;

1617

return EINTR;

1618

}

1619

1620

if(debug){

1621

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

1622

interface);

1623

}

1624

1625

/* Raise priviliges */

1626

raise_privileges();

1627

1628

#ifdef __linux__

1629

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1630

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

1631

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

1632

bool restore_loglevel = true;

1633

if(ret_linux == -1){

1634

restore_loglevel = false;

1635

perror_plus("klogctl");

1636

}

1637

#endif /* __linux__ */

1638

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

1639

ret_errno = errno;

1640

#ifdef __linux__

1641

if(restore_loglevel){

1642

ret_linux = klogctl(7, NULL, 0);

1643

if(ret_linux == -1){

1644

perror_plus("klogctl");

1645

}

1646

}

1647

#endif /* __linux__ */

1648

1649

/* Lower privileges */

1650

lower_privileges();

1651

1652

/* Close the socket */

1653

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

1654

if(ret == -1){

1655

perror_plus("close");

1656

}

1657

1658

if(ret_setflags == -1){

1659

errno = ret_errno;

1660

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1661

errno = old_errno;

1662

return ret_errno;

1663

}

1664

} else if(debug){

1665

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

1666

interface);

1667

}

1668

1669

/* Sleep checking until interface is running.

1670

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

1671

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

1672

if(interface_is_running(interface)){

1070

1673

break;

1071

1674

}

1072

}

1073

close(flags_fd);

1074

intmax_t tmpmax;

1075

char *tmp;

1076

errno = 0;

1077

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

1078

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

1079

and not (isspace(*tmp)))

1080

or tmpmax != (ifreq_flags)tmpmax){

1081

if(debug){

1082

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

1083

flagstring, if_entry->d_name);

1084

}

1085

free(flagstring);

1086

return 0;

1087

}

1088

free(flagstring);

1089

ifreq_flags flags = (ifreq_flags)tmpmax;

1090

/* Reject the loopback device */

1091

if(flags & IFF_LOOPBACK){

1092

if(debug){

1093

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

1094

if_entry->d_name);

1095

}

1096

return 0;

1097

}

1098

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

1099

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

1100

if(debug){

1101

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

1102

if_entry->d_name);

1103

}

1104

return 1;

1105

}

1106

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

1107

if(not (flags & IFF_BROADCAST)){

1108

if(debug){

1109

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

1110

if_entry->d_name);

1111

}

1112

return 0;

1113

}

1114

/* Accept this device */

1115

if(debug){

1116

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

1117

if_entry->d_name);

1118

}

1119

return 1;

1675

struct timespec sleeptime = { .tv_nsec = 250000000 };

1676

ret = nanosleep(&sleeptime, NULL);

1677

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

1678

perror_plus("nanosleep");

1679

}

1680

}

1681

1682

errno = old_errno;

1683

return 0;

1684

}

1685

1686

error_t take_down_interface(const char *const interface){

1687

int sd = -1;

1688

error_t old_errno = errno;

1689

error_t ret_errno = 0;

1690

int ret, ret_setflags;

1691

struct ifreq network;

1692

unsigned int if_index = if_nametoindex(interface);

1693

if(if_index == 0){

1694

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

1695

errno = old_errno;

1696

return ENXIO;

1697

}

1698

if(interface_is_up(interface)){

1699

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

1700

ret_errno = errno;

1701

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

1702

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

1703

return ret_errno;

1704

}

1705

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

1706

1707

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1708

if(sd < 0){

1709

ret_errno = errno;

1710

perror_plus("socket");

1711

errno = old_errno;

1712

return ret_errno;

1713

}

1714

1715

if(debug){

1716

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

1717

interface);

1718

}

1719

1720

/* Raise priviliges */

1721

raise_privileges();

1722

1723

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

1724

ret_errno = errno;

1725

1726

/* Lower privileges */

1727

lower_privileges();

1728

1729

/* Close the socket */

1730

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

1731

if(ret == -1){

1732

perror_plus("close");

1733

}

1734

1735

if(ret_setflags == -1){

1736

errno = ret_errno;

1737

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1738

errno = old_errno;

1739

return ret_errno;

1740

}

1741

} else if(debug){

1742

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

1743

interface);

1744

}

1745

1746

errno = old_errno;

1747

return 0;

1120

1748

}

1121

1749

1122

1750

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

1123

1751

AvahiSServiceBrowser *sb = NULL;

1124

int error;

1752

error_t ret_errno;

1125

1753

int ret;

1126

1754

intmax_t tmpmax;

1127

1755

char *tmp;

1128

1756

int exitcode = EXIT_SUCCESS;

1129

const char *interface = "";

1130

struct ifreq network;

1131

int sd = -1;

1132

bool take_down_interface = false;

1133

uid_t uid;

1134

gid_t gid;

1757

char *interfaces = NULL;

1758

size_t interfaces_size = 0;

1759

char *interfaces_to_take_down = NULL;

1760

size_t interfaces_to_take_down_size = 0;

1135

1761

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

1136

1762

bool tempdir_created = false;

1137

1763

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1138

1764

const char *seckey = PATHDIR "/" SECKEY;

1139

1765

const char *pubkey = PATHDIR "/" PUBKEY;

1766

char *interfaces_hooks = NULL;

1767

size_t interfaces_hooks_size = 0;

1140

1768

1141

1769

bool gnutls_initialized = false;

1142

1770

bool gpgme_initialized = false;

1143

1771

float delay = 2.5f;

1772

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

1773

retrying the same server again */

1144

1774

1145

1775

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1146

1776

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1152

1782

errno = 0;

1153

1783

ret = setgid(gid);

1154

1784

if(ret == -1){

1155

perror("setgid");

1785

perror_plus("setgid");

1156

1786

}

1157

1787

1158

1788

/* Lower user privileges (temporarily) */

1159

1789

errno = 0;

1160

1790

ret = seteuid(uid);

1161

1791

if(ret == -1){

1162

perror("seteuid");

1792

perror_plus("seteuid");

1163

1793

}

1164

1794

1165

1795

if(quit_now){

1200

1830

.arg = "SECONDS",

1201

1831

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

1202

1832

.group = 2 },

1833

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

1834

.arg = "SECONDS",

1835

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

1836

.group = 2 },

1837

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

1838

.arg = "DIR",

1839

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

1840

.group = 2 },

1203

1841

/*

1204

1842

* These reproduce what we would get without ARGP_NO_HELP

1205

1843

*/

1223

1861

connect_to = arg;

1224

1862

break;

1225

1863

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

1226

interface = arg;

1864

ret_errno = argz_add_sep(&interfaces, &interfaces_size, arg,

1865

(int)',');

1866

if(ret_errno != 0){

1867

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

1868

}

1227

1869

break;

1228

1870

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

1229

1871

seckey = arg;

1249

1891

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

1250

1892

argp_error(state, "Bad delay");

1251

1893

}

1894

case 132: /* --retry */

1895

errno = 0;

1896

retry_interval = strtod(arg, &tmp);

1897

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

1898

or (retry_interval * 1000) > INT_MAX

1899

or retry_interval < 0){

1900

argp_error(state, "Bad retry interval");

1901

}

1902

break;

1903

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

1904

hookdir = arg;

1252

1905

break;

1253

1906

/*

1254

1907

* These reproduce what we would get without ARGP_NO_HELP

1261

1914

argp_state_help(state, state->out_stream,

1262

1915

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1263

1916

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

1264

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

1917

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

1265

1918

exit(argp_err_exit_status);

1266

1919

break;

1267

1920

default:

1282

1935

case ENOMEM:

1283

1936

default:

1284

1937

errno = ret;

1285

perror("argp_parse");

1938

perror_plus("argp_parse");

1286

1939

exitcode = EX_OSERR;

1287

1940

goto end;

1288

1941

case EINVAL:

1290

1943

goto end;

1291

1944

}

1292

1945

}

1946

1947

{

1948

/* Work around Debian bug #633582:

1949

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

1950

1951

/* Re-raise priviliges */

1952

if(raise_privileges() == 0){

1953

struct stat st;

1954

1955

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

1956

int seckey_fd = open(seckey, O_RDONLY);

1957

if(seckey_fd == -1){

1958

perror_plus("open");

1959

} else {

1960

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

1961

if(ret == -1){

1962

perror_plus("fstat");

1963

} else {

1964

if(S_ISREG(st.st_mode)

1965

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

1966

ret = fchown(seckey_fd, uid, gid);

1967

if(ret == -1){

1968

perror_plus("fchown");

1969

}

1970

}

1971

}

1972

TEMP_FAILURE_RETRY(close(seckey_fd));

1973

}

1974

}

1975

1976

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

1977

int pubkey_fd = open(pubkey, O_RDONLY);

1978

if(pubkey_fd == -1){

1979

perror_plus("open");

1980

} else {

1981

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

1982

if(ret == -1){

1983

perror_plus("fstat");

1984

} else {

1985

if(S_ISREG(st.st_mode)

1986

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

1987

ret = fchown(pubkey_fd, uid, gid);

1988

if(ret == -1){

1989

perror_plus("fchown");

1990

}

1991

}

1992

}

1993

TEMP_FAILURE_RETRY(close(pubkey_fd));

1994

}

1995

}

1996

1997

/* Lower privileges */

1998

errno = 0;

1999

ret = seteuid(uid);

2000

if(ret == -1){

2001

perror_plus("seteuid");

2002

}

2003

}

2004

}

2005

2006

/* Remove empty interface names */

2007

{

2008

char *interface = NULL;

2009

while((interface = argz_next(interfaces, interfaces_size,

2010

interface))){

2011

if(if_nametoindex(interface) == 0){

2012

if(interface[0] != '\0' and strcmp(interface, "none") != 0){

2013

fprintf_plus(stderr, "Not using nonexisting interface"

2014

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

2015

}

2016

argz_delete(&interfaces, &interfaces_size, interface);

2017

interface = NULL;

2018

}

2019

}

2020

}

2021

2022

/* Run network hooks */

2023

{

2024

2025

if(interfaces != NULL){

2026

interfaces_hooks = malloc(interfaces_size);

2027

if(interfaces_hooks == NULL){

2028

perror_plus("malloc");

2029

goto end;

2030

}

2031

memcpy(interfaces_hooks, interfaces, interfaces_size);

2032

interfaces_hooks_size = interfaces_size;

2033

argz_stringify(interfaces_hooks, interfaces_hooks_size,

2034

(int)',');

2035

}

2036

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

2037

interfaces_hooks : "", delay)){

2038

goto end;

2039

}

2040

}

1293

2041

1294

2042

if(not debug){

1295

2043

avahi_set_log_function(empty_log);

1296

2044

}

1297

1298

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

1299

struct dirent **direntries;

1300

ret = scandir(sys_class_net, &direntries, good_interface,

1301

alphasort);

1302

if(ret >= 1){

1303

/* Pick the first good interface */

1304

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

1305

if(debug){

1306

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

1307

}

1308

if(interface == NULL){

1309

perror("malloc");

1310

free(direntries);

1311

exitcode = EXIT_FAILURE;

1312

goto end;

1313

}

1314

free(direntries);

1315

} else {

1316

free(direntries);

1317

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

1318

exitcode = EXIT_FAILURE;

1319

goto end;

1320

}

1321

}

1322

2045

1323

2046

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

1324

2047

from the signal handler */

1326

2049

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

1327

2050

mc.simple_poll = avahi_simple_poll_new();

1328

2051

if(mc.simple_poll == NULL){

1329

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

2052

fprintf_plus(stderr,

2053

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

1330

2054

exitcode = EX_UNAVAILABLE;

1331

2055

goto end;

1332

2056

}

1334

2058

sigemptyset(&sigterm_action.sa_mask);

1335

2059

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

1336

2060

if(ret == -1){

1337

perror("sigaddset");

2061

perror_plus("sigaddset");

1338

2062

exitcode = EX_OSERR;

1339

2063

goto end;

1340

2064

}

1341

2065

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

1342

2066

if(ret == -1){

1343

perror("sigaddset");

2067

perror_plus("sigaddset");

1344

2068

exitcode = EX_OSERR;

1345

2069

goto end;

1346

2070

}

1347

2071

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

1348

2072

if(ret == -1){

1349

perror("sigaddset");

2073

perror_plus("sigaddset");

1350

2074

exitcode = EX_OSERR;

1351

2075

goto end;

1352

2076

}

1356

2080

*/

1357

2081

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

1358

2082

if(ret == -1){

1359

perror("sigaction");

2083

perror_plus("sigaction");

1360

2084

return EX_OSERR;

1361

2085

}

1362

2086

if(old_sigterm_action.sa_handler != SIG_IGN){

1363

2087

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

1364

2088

if(ret == -1){

1365

perror("sigaction");

2089

perror_plus("sigaction");

1366

2090

exitcode = EX_OSERR;

1367

2091

goto end;

1368

2092

}

1369

2093

}

1370

2094

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

1371

2095

if(ret == -1){

1372

perror("sigaction");

2096

perror_plus("sigaction");

1373

2097

return EX_OSERR;

1374

2098

}

1375

2099

if(old_sigterm_action.sa_handler != SIG_IGN){

1376

2100

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

1377

2101

if(ret == -1){

1378

perror("sigaction");

2102

perror_plus("sigaction");

1379

2103

exitcode = EX_OSERR;

1380

2104

goto end;

1381

2105

}

1382

2106

}

1383

2107

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

1384

2108

if(ret == -1){

1385

perror("sigaction");

2109

perror_plus("sigaction");

1386

2110

return EX_OSERR;

1387

2111

}

1388

2112

if(old_sigterm_action.sa_handler != SIG_IGN){

1389

2113

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

1390

2114

if(ret == -1){

1391

perror("sigaction");

2115

perror_plus("sigaction");

1392

2116

exitcode = EX_OSERR;

1393

2117

goto end;

1394

2118

}

1395

2119

}

1396

2120

1397

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

1398

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

1399

if_index = (AvahiIfIndex) if_nametoindex(interface);

1400

if(if_index == 0){

1401

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

1402

exitcode = EX_UNAVAILABLE;

1403

goto end;

1404

}

1405

1406

if(quit_now){

1407

goto end;

1408

}

1409

1410

/* Re-raise priviliges */

1411

errno = 0;

1412

ret = seteuid(0);

1413

if(ret == -1){

1414

perror("seteuid");

1415

}

1416

1417

#ifdef __linux__

1418

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1419

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

1420

ret = klogctl(8, NULL, 5);

1421

bool restore_loglevel = true;

1422

if(ret == -1){

1423

restore_loglevel = false;

1424

perror("klogctl");

1425

}

1426

#endif /* __linux__ */

1427

1428

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1429

if(sd < 0){

1430

perror("socket");

1431

exitcode = EX_OSERR;

1432

#ifdef __linux__

1433

if(restore_loglevel){

1434

ret = klogctl(7, NULL, 0);

1435

if(ret == -1){

1436

perror("klogctl");

1437

}

1438

}

1439

#endif /* __linux__ */

1440

/* Lower privileges */

1441

errno = 0;

1442

ret = seteuid(uid);

1443

if(ret == -1){

1444

perror("seteuid");

1445

}

1446

goto end;

1447

}

1448

strcpy(network.ifr_name, interface);

1449

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

1450

if(ret == -1){

1451

perror("ioctl SIOCGIFFLAGS");

1452

#ifdef __linux__

1453

if(restore_loglevel){

1454

ret = klogctl(7, NULL, 0);

1455

if(ret == -1){

1456

perror("klogctl");

1457

}

1458

}

1459

#endif /* __linux__ */

1460

exitcode = EX_OSERR;

1461

/* Lower privileges */

1462

errno = 0;

1463

ret = seteuid(uid);

1464

if(ret == -1){

1465

perror("seteuid");

1466

}

1467

goto end;

1468

}

1469

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

1470

network.ifr_flags |= IFF_UP;

1471

take_down_interface = true;

1472

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

1473

if(ret == -1){

1474

take_down_interface = false;

1475

perror("ioctl SIOCSIFFLAGS +IFF_UP");

1476

exitcode = EX_OSERR;

1477

#ifdef __linux__

1478

if(restore_loglevel){

1479

ret = klogctl(7, NULL, 0);

1480

if(ret == -1){

1481

perror("klogctl");

1482

}

1483

}

1484

#endif /* __linux__ */

1485

/* Lower privileges */

1486

errno = 0;

1487

ret = seteuid(uid);

1488

if(ret == -1){

1489

perror("seteuid");

1490

}

1491

goto end;

1492

}

1493

}

1494

/* sleep checking until interface is running */

1495

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

1496

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

1497

if(ret == -1){

1498

perror("ioctl SIOCGIFFLAGS");

1499

} else if(network.ifr_flags & IFF_RUNNING){

1500

break;

1501

}

1502

struct timespec sleeptime = { .tv_nsec = 250000000 };

1503

ret = nanosleep(&sleeptime, NULL);

1504

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

1505

perror("nanosleep");

1506

}

1507

}

1508

if(not take_down_interface){

1509

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

1510

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

1511

if(ret == -1){

1512

perror("close");

1513

}

1514

}

1515

#ifdef __linux__

1516

if(restore_loglevel){

1517

/* Restores kernel loglevel to default */

1518

ret = klogctl(7, NULL, 0);

1519

if(ret == -1){

1520

perror("klogctl");

1521

}

1522

}

1523

#endif /* __linux__ */

1524

/* Lower privileges */

1525

errno = 0;

1526

if(take_down_interface){

1527

/* Lower privileges */

1528

ret = seteuid(uid);

1529

if(ret == -1){

1530

perror("seteuid");

1531

}

2121

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

2122

if(interfaces == NULL){

2123

struct dirent **direntries;

2124

/* Look for any good interfaces */

2125

ret = scandir(sys_class_net, &direntries, good_interface,

2126

alphasort);

2127

if(ret >= 1){

2128

/* Add all found interfaces to interfaces list */

2129

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

2130

ret_errno = argz_add(&interfaces, &interfaces_size,

2131

direntries[i]->d_name);

2132

if(ret_errno != 0){

2133

perror_plus("argz_add");

2134

continue;

2135

}

2136

if(debug){

2137

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

2138

direntries[i]->d_name);

2139

}

2140

}

2141

free(direntries);

1532

2142

} else {

1533

/* Lower privileges permanently */

1534

ret = setuid(uid);

1535

if(ret == -1){

1536

perror("setuid");

2143

free(direntries);

2144

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

2145

exitcode = EXIT_FAILURE;

2146

goto end;

2147

}

2148

}

2149

2150

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

2151

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

2152

if(debug){

2153

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

2154

interfaces);

2155

}

2156

if_index = (AvahiIfIndex)if_nametoindex(interfaces);

2157

}

2158

2159

/* Bring up interfaces which are down */

2160

if(not (argz_count(interfaces, interfaces_size) == 1

2161

and strcmp(interfaces, "none") == 0)){

2162

char *interface = NULL;

2163

while((interface = argz_next(interfaces, interfaces_size,

2164

interface))){

2165

bool interface_was_up = interface_is_up(interface);

2166

ret = bring_up_interface(interface, delay);

2167

if(not interface_was_up){

2168

if(ret != 0){

2169

errno = ret;

2170

perror_plus("Failed to bring up interface");

2171

} else {

2172

ret_errno = argz_add(&interfaces_to_take_down,

2173

&interfaces_to_take_down_size,

2174

interface);

2175

}

1537

2176

}

1538

2177

}

2178

free(interfaces);

2179

interfaces = NULL;

2180

interfaces_size = 0;

2181

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

2182

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

2183

}

1539

2184

}

1540

2185

1541

2186

if(quit_now){

1544

2189

1545

2190

ret = init_gnutls_global(pubkey, seckey);

1546

2191

if(ret == -1){

1547

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

2192

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

1548

2193

exitcode = EX_UNAVAILABLE;

1549

2194

goto end;

1550

2195

} else {

1555

2200

goto end;

1556

2201

}

1557

2202

2203

if(mkdtemp(tempdir) == NULL){

2204

perror_plus("mkdtemp");

2205

goto end;

2206

}

1558

2207

tempdir_created = true;

1559

if(mkdtemp(tempdir) == NULL){

1560

tempdir_created = false;

1561

perror("mkdtemp");

1562

goto end;

1563

}

1564

2208

1565

2209

if(quit_now){

1566

2210

goto end;

1567

2211

}

1568

2212

1569

2213

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

1570

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

2214

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

1571

2215

exitcode = EX_UNAVAILABLE;

1572

2216

goto end;

1573

2217

} else {

1582

2226

/* Connect directly, do not use Zeroconf */

1583

2227

/* (Mainly meant for debugging) */

1584

2228

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

2229

1585

2230

if(address == NULL){

1586

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

2231

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

1587

2232

exitcode = EX_USAGE;

1588

2233

goto end;

1589

2234

}

1592

2237

goto end;

1593

2238

}

1594

2239

1595

uint16_t port;

2240

in_port_t port;

1596

2241

errno = 0;

1597

2242

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

1598

2243

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

1599

or tmpmax != (uint16_t)tmpmax){

1600

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

2244

or tmpmax != (in_port_t)tmpmax){

2245

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

1601

2246

exitcode = EX_USAGE;

1602

2247

goto end;

1603

2248

}

1606

2251

goto end;

1607

2252

}

1608

2253

1609

port = (uint16_t)tmpmax;

2254

port = (in_port_t)tmpmax;

1610

2255

*address = '\0';

1611

address = connect_to;

1612

2256

/* Colon in address indicates IPv6 */

1613

2257

int af;

1614

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

2258

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

1615

2259

af = AF_INET6;

2260

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

2261

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

2262

{

2263

connect_to++;

2264

address[-1] = '\0';

2265

}

1616

2266

} else {

1617

2267

af = AF_INET;

1618

2268

}

2269

address = connect_to;

1619

2270

1620

2271

if(quit_now){

1621

2272

goto end;

1622

2273

}

1623

2274

1624

2275

while(not quit_now){

1625

2276

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

1626

2277

if(quit_now or ret == 0){

1627

2278

break;

1628

2279

}

1629

sleep(15);

1630

};

1631

2280

if(debug){

2281

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

2282

(int)retry_interval);

2283

}

2284

sleep((int)retry_interval);

2285

}

2286

1632

2287

if (not quit_now){

1633

2288

exitcode = EXIT_SUCCESS;

1634

2289

}

1635

2290

1636

2291

goto end;

1637

2292

}

1638

2293

1652

2307

/* Allocate a new server */

1653

2308

mc.server = avahi_server_new(avahi_simple_poll_get

1654

2309

(mc.simple_poll), &config, NULL,

1655

NULL, &error);

2310

NULL, &ret_errno);

1656

2311

1657

2312

/* Free the Avahi configuration data */

1658

2313

avahi_server_config_free(&config);

1660

2315

1661

2316

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

1662

2317

if(mc.server == NULL){

1663

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

1664

avahi_strerror(error));

2318

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

2319

avahi_strerror(ret_errno));

1665

2320

exitcode = EX_UNAVAILABLE;

1666

2321

goto end;

1667

2322

}

1675

2330

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1676

2331

NULL, 0, browse_callback, NULL);

1677

2332

if(sb == NULL){

1678

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

1679

avahi_strerror(avahi_server_errno(mc.server)));

2333

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

2334

avahi_strerror(avahi_server_errno(mc.server)));

1680

2335

exitcode = EX_UNAVAILABLE;

1681

2336

goto end;

1682

2337

}

1688

2343

/* Run the main loop */

1689

2344

1690

2345

if(debug){

1691

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

1692

}

1693

1694

avahi_simple_poll_loop(mc.simple_poll);

2346

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

2347

}

2348

2349

ret = avahi_loop_with_timeout(mc.simple_poll,

2350

(int)(retry_interval * 1000));

2351

if(debug){

2352

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

2353

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

2354

}

1695

2355

1696

2356

end:

1697

2357

1698

2358

if(debug){

1699

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

2359

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

1700

2360

}

1701

2361

1702

2362

/* Cleanup things */

1719

2379

gpgme_release(mc.ctx);

1720

2380

}

1721

2381

1722

/* Take down the network interface */

1723

if(take_down_interface){

1724

/* Re-raise priviliges */

1725

errno = 0;

1726

ret = seteuid(0);

1727

if(ret == -1){

1728

perror("seteuid");

2382

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

2383

has seen */

2384

if(mc.current_server != NULL){

2385

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

2386

while(mc.current_server != NULL){

2387

server *next = mc.current_server->next;

2388

free(mc.current_server);

2389

mc.current_server = next;

1729

2390

}

1730

if(geteuid() == 0){

1731

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

1732

if(ret == -1){

1733

perror("ioctl SIOCGIFFLAGS");

1734

} else if(network.ifr_flags & IFF_UP) {

1735

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

1736

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

1737

if(ret == -1){

1738

perror("ioctl SIOCSIFFLAGS -IFF_UP");

2391

}

2392

2393

/* Re-raise priviliges */

2394

{

2395

raise_privileges();

2396

2397

/* Run network hooks */

2398

run_network_hooks("stop", interfaces_hooks != NULL ?

2399

interfaces_hooks : "", delay);

2400

2401

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

2402

{

2403

char *interface = NULL;

2404

while((interface=argz_next(interfaces_to_take_down,

2405

interfaces_to_take_down_size,

2406

interface))){

2407

ret_errno = take_down_interface(interface);

2408

if(ret_errno != 0){

2409

errno = ret_errno;

2410

perror_plus("Failed to take down interface");

1739

2411

}

1740

2412

}

1741

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

1742

if(ret == -1){

1743

perror("close");

1744

}

1745

/* Lower privileges permanently */

1746

errno = 0;

1747

ret = setuid(uid);

1748

if(ret == -1){

1749

perror("setuid");

2413

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

2414

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

2415

" down\n");

1750

2416

}

1751

2417

}

2418

2419

lower_privileges_permanently();

1752

2420

}

1753

2421

1754

/* Removes the temp directory used by GPGME */

2422

free(interfaces_to_take_down);

2423

free(interfaces_hooks);

2424

2425

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

1755

2426

if(tempdir_created){

1756

DIR *d;

1757

struct dirent *direntry;

1758

d = opendir(tempdir);

1759

if(d == NULL){

1760

if(errno != ENOENT){

1761

perror("opendir");

1762

}

1763

} else {

1764

while(true){

1765

direntry = readdir(d);

1766

if(direntry == NULL){

1767

break;

1768

}

1769

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

1770

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

1771

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

1772

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

1773

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

1774

continue;

1775

}

2427

struct dirent **direntries = NULL;

2428

struct dirent *direntry = NULL;

2429

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

2430

alphasort);

2431

if (numentries > 0){

2432

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

2433

direntry = direntries[i];

1776

2434

char *fullname = NULL;

1777

2435

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

1778

2436

direntry->d_name);

1779

2437

if(ret < 0){

1780

perror("asprintf");

2438

perror_plus("asprintf");

1781

2439

continue;

1782

2440

}

1783

2441

ret = remove(fullname);

1784

2442

if(ret == -1){

1785

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

1786

strerror(errno));

2443

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

2444

strerror(errno));

1787

2445

}

1788

2446

free(fullname);

1789

2447

}

1790

closedir(d);

2448

}

2449

2450

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

2451

free(direntries);

2452

if (numentries == -1){

2453

perror_plus("scandir");

1791

2454

}

1792

2455

ret = rmdir(tempdir);

1793

2456

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

1794

perror("rmdir");

2457

perror_plus("rmdir");

1795

2458

}

1796

2459

}

1797

2460

1802

2465

&old_sigterm_action,

1803

2466

NULL));

1804

2467

if(ret == -1){

1805

perror("sigaction");

2468

perror_plus("sigaction");

1806

2469

}

1807

2470

do {

1808

2471

ret = raise(signal_received);

1809

2472

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

1810

2473

if(ret != 0){

1811

perror("raise");

2474

perror_plus("raise");

1812

2475

abort();

1813

2476

}

1814

2477

TEMP_FAILURE_RETRY(pause());