/mandos/trunk : revision 304

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

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*

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* Everything else is

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*

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

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

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* along with this program. If not, see

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

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*

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

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

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*/

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

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#ifndef _LARGEFILE_SOURCE

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33

#define _LARGEFILE_SOURCE

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#endif

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#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

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#endif

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

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

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stdout, ferror(), remove() */

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stdout, ferror(), sscanf(),

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remove() */

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

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

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

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strtof(), abort() */

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

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srand() */

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#include <stdbool.h> /* bool, false, true */

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#include <string.h> /* memset(), strcmp(), strlen(),

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strerror(), asprintf(), strcpy() */

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sockaddr_in6, PF_INET6,

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SOCK_STREAM, uid_t, gid_t, open(),

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opendir(), DIR */

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

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

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

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inet_pton(), connect() */

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

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

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*/

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

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strtoimax() */

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

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#include <assert.h> /* assert() */

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

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program_invocation_short_name */

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

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

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

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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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INET_ADDRSTRLEN, INET6_ADDRSTRLEN

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*/

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

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

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

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

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getuid(), getgid(), setuid(),

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setgid() */

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

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

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

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argp_state, struct argp,

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argp_parse(), ARGP_KEY_ARG,

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ARGP_KEY_END, ARGP_ERR_UNKNOWN */

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#include <signal.h> /* sigemptyset(), sigaddset(),

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sigaction(), SIGTERM, sig_atomic_t,

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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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#ifdef __linux__

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

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#endif /* __linux__ */

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#endif

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/* Avahi */

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/* All Avahi types, constants and functions

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init_gnutls_session(),

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98

GNUTLS_* */

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#include <gnutls/openpgp.h>

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/* gnutls_certificate_set_openpgp_key_file(),

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GNUTLS_OPENPGP_FMT_BASE64 */

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/* gnutls_certificate_set_openpgp_key_file(),

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GNUTLS_OPENPGP_FMT_BASE64 */

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/* GPGME */

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#include <gpgme.h> /* All GPGME types, constants and

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

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#define SECKEY "seckey.txt"

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114

#define PUBKEY "pubkey.txt"

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

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bool debug = false;

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static const char mandos_protocol_version[] = "1";

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const char *argp_program_version = "mandos-client " VERSION;

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

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

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char *connect_to = NULL;

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const char *hookdir = HOOKDIR;

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

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typedef struct server{

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const char *ip;

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uint16_t port;

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

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

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122

typedef struct {

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127

gnutls_dh_params_t dh_params;

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128

const char *priority;

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129

gpgme_ctx_t ctx;

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server *current_server;

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130

} mandos_context;

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131

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/* global context so signal handler can reach it*/

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mandos_context mc = { .simple_poll = NULL, .server = NULL,

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.dh_bits = 1024, .priority = "SECURE256"

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

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.current_server = NULL };

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168

sig_atomic_t quit_now = 0;

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int signal_received = 0;

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171

/* Function to use when printing errors */

172

void perror_plus(const char *print_text){

173

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;

177

perror(print_text);

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}

179

180

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

181

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

182

va_list ap;

183

va_start (ap, format);

184

185

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

186

program_invocation_short_name));

187

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

188

}

189

190

132

/*

191

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

192

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

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* Make room in "buffer" for at least BUFFER_SIZE additional bytes.

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* "buffer_capacity" is how much is currently allocated,

193

135

* "buffer_length" is how much is already used.

194

136

*/

195

size_t incbuffer(char **buffer, size_t buffer_length,

196

size_t buffer_capacity){

137

size_t adjustbuffer(char **buffer, size_t buffer_length,

138

size_t buffer_capacity){

197

139

if(buffer_length + BUFFER_SIZE > buffer_capacity){

198

140

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

199

141

if(buffer == NULL){

204

146

return buffer_capacity;

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147

}

206

148

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

208

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

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int af){

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int ret;

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

212

if(new_server == NULL){

213

perror_plus("malloc");

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return false;

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}

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

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.port = port,

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.if_index = if_index,

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.af = af };

220

if(new_server->ip == NULL){

221

perror_plus("strdup");

222

return false;

223

}

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/* Special case of first server */

225

if (mc.current_server == NULL){

226

new_server->next = new_server;

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new_server->prev = new_server;

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mc.current_server = new_server;

229

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

230

} else {

231

new_server->next = mc.current_server;

232

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

233

new_server->prev->next = new_server;

234

mc.current_server->prev = new_server;

235

}

236

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

237

if(ret == -1){

238

perror_plus("clock_gettime");

239

return false;

240

}

241

return true;

242

}

243

244

149

/*

245

150

* Initialize GPGME.

246

151

*/

247

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

248

const char *tempdir){

152

static bool init_gpgme(mandos_context *mc, const char *seckey,

153

const char *pubkey, const char *tempdir){

154

int ret;

249

155

gpgme_error_t rc;

250

156

gpgme_engine_info_t engine_info;

251

157

254

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

255

161

*/

256

162

bool import_key(const char *filename){

257

int ret;

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int fd;

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164

gpgme_data_t pgp_data;

260

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261

166

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

262

167

if(fd == -1){

263

perror_plus("open");

168

perror("open");

264

169

return false;

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170

}

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rc = gpgme_data_new_from_fd(&pgp_data, fd);

268

173

if(rc != GPG_ERR_NO_ERROR){

269

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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176

return false;

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177

}

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178

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rc = gpgme_op_import(mc.ctx, pgp_data);

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

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if(rc != GPG_ERR_NO_ERROR){

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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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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183

return false;

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}

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

282

187

if(ret == -1){

283

perror_plus("close");

188

perror("close");

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}

285

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gpgme_data_release(pgp_data);

286

191

return true;

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192

}

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193

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if(debug){

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

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fprintf(stderr, "Initialize gpgme\n");

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}

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/* Init GPGME */

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199

gpgme_check_version(NULL);

295

200

rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

296

201

if(rc != GPG_ERR_NO_ERROR){

297

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

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gpgme_strsource(rc), gpgme_strerror(rc));

202

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

203

gpgme_strsource(rc), gpgme_strerror(rc));

299

204

return false;

300

205

}

301

206

302

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

207

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

303

208

rc = gpgme_get_engine_info(&engine_info);

304

209

if(rc != GPG_ERR_NO_ERROR){

305

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

306

gpgme_strsource(rc), gpgme_strerror(rc));

210

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

211

gpgme_strsource(rc), gpgme_strerror(rc));

307

212

return false;

308

213

}

309

214

while(engine_info != NULL){

315

220

engine_info = engine_info->next;

316

221

}

317

222

if(engine_info == NULL){

318

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

319

tempdir);

223

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

320

224

return false;

321

225

}

322

226

323

227

/* Create new GPGME "context" */

324

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

228

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

325

229

if(rc != GPG_ERR_NO_ERROR){

326

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

327

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

328

gpgme_strerror(rc));

230

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

231

gpgme_strsource(rc), gpgme_strerror(rc));

329

232

return false;

330

233

}

331

234

333

236

return false;

334

237

}

335

238

336

return true;

239

return true;

337

240

}

338

241

339

242

/*

340

243

* Decrypt OpenPGP data.

341

244

* Returns -1 on error

342

245

*/

343

static ssize_t pgp_packet_decrypt(const char *cryptotext,

246

static ssize_t pgp_packet_decrypt(const mandos_context *mc,

247

const char *cryptotext,

344

248

size_t crypto_size,

345

249

char **plaintext){

346

250

gpgme_data_t dh_crypto, dh_plain;

350

254

ssize_t plaintext_length = 0;

351

255

352

256

if(debug){

353

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

257

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

354

258

}

355

259

356

260

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

357

261

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

358

262

0);

359

263

if(rc != GPG_ERR_NO_ERROR){

360

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

361

gpgme_strsource(rc), gpgme_strerror(rc));

264

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

265

gpgme_strsource(rc), gpgme_strerror(rc));

362

266

return -1;

363

267

}

364

268

365

269

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

366

270

rc = gpgme_data_new(&dh_plain);

367

271

if(rc != GPG_ERR_NO_ERROR){

368

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

369

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

370

gpgme_strsource(rc), gpgme_strerror(rc));

272

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

273

gpgme_strsource(rc), gpgme_strerror(rc));

371

274

gpgme_data_release(dh_crypto);

372

275

return -1;

373

276

}

374

277

375

278

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

376

279

data buffer */

377

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

280

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

378

281

if(rc != GPG_ERR_NO_ERROR){

379

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

380

gpgme_strsource(rc), gpgme_strerror(rc));

282

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

283

gpgme_strsource(rc), gpgme_strerror(rc));

381

284

plaintext_length = -1;

382

285

if(debug){

383

286

gpgme_decrypt_result_t result;

384

result = gpgme_op_decrypt_result(mc.ctx);

287

result = gpgme_op_decrypt_result(mc->ctx);

385

288

if(result == NULL){

386

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

289

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

387

290

} else {

388

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

389

result->unsupported_algorithm);

390

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

391

result->wrong_key_usage);

291

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

292

result->unsupported_algorithm);

293

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

294

result->wrong_key_usage);

392

295

if(result->file_name != NULL){

393

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

296

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

394

297

}

395

298

gpgme_recipient_t recipient;

396

299

recipient = result->recipients;

397

while(recipient != NULL){

398

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

399

gpgme_pubkey_algo_name

400

(recipient->pubkey_algo));

401

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

402

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

403

recipient->status == GPG_ERR_NO_SECKEY

404

? "No" : "Yes");

405

recipient = recipient->next;

300

if(recipient){

301

while(recipient != NULL){

302

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

303

gpgme_pubkey_algo_name(recipient->pubkey_algo));

304

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

305

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

306

recipient->status == GPG_ERR_NO_SECKEY

307

? "No" : "Yes");

308

recipient = recipient->next;

309

}

406

310

}

407

311

}

408

312

}

410

314

}

411

315

412

316

if(debug){

413

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

317

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

414

318

}

415

319

416

320

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

417

321

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

418

perror_plus("gpgme_data_seek");

322

perror("gpgme_data_seek");

419

323

plaintext_length = -1;

420

324

goto decrypt_end;

421

325

}

422

326

423

327

*plaintext = NULL;

424

328

while(true){

425

plaintext_capacity = incbuffer(plaintext,

426

(size_t)plaintext_length,

427

plaintext_capacity);

329

plaintext_capacity = adjustbuffer(plaintext,

330

(size_t)plaintext_length,

331

plaintext_capacity);

428

332

if(plaintext_capacity == 0){

429

perror_plus("incbuffer");

430

plaintext_length = -1;

431

goto decrypt_end;

333

perror("adjustbuffer");

334

plaintext_length = -1;

335

goto decrypt_end;

432

336

}

433

337

434

338

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

439

343

break;

440

344

}

441

345

if(ret < 0){

442

perror_plus("gpgme_data_read");

346

perror("gpgme_data_read");

443

347

plaintext_length = -1;

444

348

goto decrypt_end;

445

349

}

447

351

}

448

352

449

353

if(debug){

450

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

354

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

451

355

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

452

356

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

453

357

}

475

379

/* GnuTLS log function callback */

476

380

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

477

381

const char* string){

478

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

382

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

479

383

}

480

384

481

static int init_gnutls_global(const char *pubkeyfilename,

385

static int init_gnutls_global(mandos_context *mc,

386

const char *pubkeyfilename,

482

387

const char *seckeyfilename){

483

388

int ret;

484

389

485

390

if(debug){

486

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

391

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

487

392

}

488

393

489

394

ret = gnutls_global_init();

490

395

if(ret != GNUTLS_E_SUCCESS){

491

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

492

safer_gnutls_strerror(ret));

396

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

397

safer_gnutls_strerror(ret));

493

398

return -1;

494

399

}

495

400

502

407

}

503

408

504

409

/* OpenPGP credentials */

505

ret = gnutls_certificate_allocate_credentials(&mc.cred);

410

gnutls_certificate_allocate_credentials(&mc->cred);

506

411

if(ret != GNUTLS_E_SUCCESS){

507

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

508

safer_gnutls_strerror(ret));

412

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

413

from

414

-Wunreachable-code

415

*/

416

safer_gnutls_strerror(ret));

509

417

gnutls_global_deinit();

510

418

return -1;

511

419

}

512

420

513

421

if(debug){

514

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

515

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

516

pubkeyfilename,

517

seckeyfilename);

422

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

423

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

424

seckeyfilename);

518

425

}

519

426

520

427

ret = gnutls_certificate_set_openpgp_key_file

521

(mc.cred, pubkeyfilename, seckeyfilename,

428

(mc->cred, pubkeyfilename, seckeyfilename,

522

429

GNUTLS_OPENPGP_FMT_BASE64);

523

430

if(ret != GNUTLS_E_SUCCESS){

524

fprintf_plus(stderr,

525

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

526

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

527

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

528

safer_gnutls_strerror(ret));

431

fprintf(stderr,

432

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

433

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

434

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

435

safer_gnutls_strerror(ret));

529

436

goto globalfail;

530

437

}

531

438

532

439

/* GnuTLS server initialization */

533

ret = gnutls_dh_params_init(&mc.dh_params);

440

ret = gnutls_dh_params_init(&mc->dh_params);

534

441

if(ret != GNUTLS_E_SUCCESS){

535

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

536

" initialization: %s\n",

537

safer_gnutls_strerror(ret));

442

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

443

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

538

444

goto globalfail;

539

445

}

540

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

446

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

541

447

if(ret != GNUTLS_E_SUCCESS){

542

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

543

safer_gnutls_strerror(ret));

448

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

449

safer_gnutls_strerror(ret));

544

450

goto globalfail;

545

451

}

546

452

547

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

453

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

548

454

549

455

return 0;

550

456

551

457

globalfail:

552

458

553

gnutls_certificate_free_credentials(mc.cred);

459

gnutls_certificate_free_credentials(mc->cred);

554

460

gnutls_global_deinit();

555

gnutls_dh_params_deinit(mc.dh_params);

461

gnutls_dh_params_deinit(mc->dh_params);

556

462

return -1;

557

463

}

558

464

559

static int init_gnutls_session(gnutls_session_t *session){

465

static int init_gnutls_session(mandos_context *mc,

466

gnutls_session_t *session){

560

467

int ret;

561

468

/* GnuTLS session creation */

562

do {

563

ret = gnutls_init(session, GNUTLS_SERVER);

564

if(quit_now){

565

return -1;

566

}

567

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

469

ret = gnutls_init(session, GNUTLS_SERVER);

568

470

if(ret != GNUTLS_E_SUCCESS){

569

fprintf_plus(stderr,

570

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

571

safer_gnutls_strerror(ret));

471

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

472

safer_gnutls_strerror(ret));

572

473

}

573

474

574

475

{

575

476

const char *err;

576

do {

577

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

578

if(quit_now){

579

gnutls_deinit(*session);

580

return -1;

581

}

582

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

477

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

583

478

if(ret != GNUTLS_E_SUCCESS){

584

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

585

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

586

safer_gnutls_strerror(ret));

479

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

480

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

481

safer_gnutls_strerror(ret));

587

482

gnutls_deinit(*session);

588

483

return -1;

589

484

}

590

485

}

591

486

592

do {

593

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

594

mc.cred);

595

if(quit_now){

596

gnutls_deinit(*session);

597

return -1;

598

}

599

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

487

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

488

mc->cred);

600

489

if(ret != GNUTLS_E_SUCCESS){

601

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

602

safer_gnutls_strerror(ret));

490

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

491

safer_gnutls_strerror(ret));

603

492

gnutls_deinit(*session);

604

493

return -1;

605

494

}

606

495

607

496

/* ignore client certificate if any. */

608

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

497

gnutls_certificate_server_set_request(*session,

498

GNUTLS_CERT_IGNORE);

609

499

610

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

500

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

611

501

612

502

return 0;

613

503

}

619

509

/* Called when a Mandos server is found */

620

510

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

621

511

AvahiIfIndex if_index,

622

int af){

623

int ret, tcp_sd = -1;

512

mandos_context *mc, int af){

513

int ret, tcp_sd;

624

514

ssize_t sret;

625

515

union {

626

516

struct sockaddr_in in;

627

517

struct sockaddr_in6 in6;

628

518

} to;

629

519

char *buffer = NULL;

630

char *decrypted_buffer = NULL;

520

char *decrypted_buffer;

631

521

size_t buffer_length = 0;

632

522

size_t buffer_capacity = 0;

523

ssize_t decrypted_buffer_size;

633

524

size_t written;

634

int retval = -1;

525

int retval = 0;

635

526

gnutls_session_t session;

636

527

int pf; /* Protocol family */

637

528

638

errno = 0;

639

640

if(quit_now){

641

errno = EINTR;

642

return -1;

643

}

644

645

529

switch(af){

646

530

case AF_INET6:

647

531

pf = PF_INET6;

650

534

pf = PF_INET;

651

535

break;

652

536

default:

653

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

654

errno = EINVAL;

537

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

655

538

return -1;

656

539

}

657

540

658

ret = init_gnutls_session(&session);

541

ret = init_gnutls_session(mc, &session);

659

542

if(ret != 0){

660

543

return -1;

661

544

}

662

545

663

546

if(debug){

664

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

665

PRIu16 "\n", ip, port);

547

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

548

"\n", ip, port);

666

549

}

667

550

668

551

tcp_sd = socket(pf, SOCK_STREAM, 0);

669

552

if(tcp_sd < 0){

670

int e = errno;

671

perror_plus("socket");

672

errno = e;

673

goto mandos_end;

674

}

675

676

if(quit_now){

677

errno = EINTR;

678

goto mandos_end;

553

perror("socket");

554

return -1;

679

555

}

680

556

681

557

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

682

558

if(af == AF_INET6){

683

to.in6.sin6_family = (sa_family_t)af;

559

to.in6.sin6_family = (uint16_t)af;

684

560

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

685

561

} else { /* IPv4 */

686

562

to.in.sin_family = (sa_family_t)af;

687

563

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

688

564

}

689

565

if(ret < 0 ){

690

int e = errno;

691

perror_plus("inet_pton");

692

errno = e;

693

goto mandos_end;

566

perror("inet_pton");

567

return -1;

694

568

}

695

569

if(ret == 0){

696

int e = errno;

697

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

698

errno = e;

699

goto mandos_end;

570

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

571

return -1;

700

572

}

701

573

if(af == AF_INET6){

702

574

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

705

577

706

578

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

707

579

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

708

-Wunreachable-code*/

580

-Wunreachable-code*/

709

581

if(if_index == AVAHI_IF_UNSPEC){

710

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

711

" incomplete without a network interface\n");

712

errno = EINVAL;

713

goto mandos_end;

582

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

583

" without a network interface\n");

584

return -1;

714

585

}

715

586

/* Set the network interface number as scope */

716

587

to.in6.sin6_scope_id = (uint32_t)if_index;

721

592

-Wunreachable-code */

722

593

}

723

594

724

if(quit_now){

725

errno = EINTR;

726

goto mandos_end;

727

}

728

729

595

if(debug){

730

596

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

731

597

char interface[IF_NAMESIZE];

732

598

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

733

perror_plus("if_indextoname");

599

perror("if_indextoname");

734

600

} else {

735

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

736

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

601

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

602

ip, interface, port);

737

603

}

738

604

} else {

739

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

740

ip, port);

605

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

606

port);

741

607

}

742

608

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

743

609

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

750

616

sizeof(addrstr));

751

617

}

752

618

if(pcret == NULL){

753

perror_plus("inet_ntop");

619

perror("inet_ntop");

754

620

} else {

755

621

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

756

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

622

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

757

623

}

758

624

}

759

625

}

760

626

761

if(quit_now){

762

errno = EINTR;

763

goto mandos_end;

764

}

765

766

627

if(af == AF_INET6){

767

628

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

768

629

} else {

769

630

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

770

631

}

771

632

if(ret < 0){

772

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

773

int e = errno;

774

perror_plus("connect");

775

errno = e;

776

}

777

goto mandos_end;

778

}

779

780

if(quit_now){

781

errno = EINTR;

782

goto mandos_end;

633

perror("connect");

634

return -1;

783

635

}

784

636

785

637

const char *out = mandos_protocol_version;

787

639

while(true){

788

640

size_t out_size = strlen(out);

789

641

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

790

out_size - written));

642

out_size - written));

791

643

if(ret == -1){

792

int e = errno;

793

perror_plus("write");

794

errno = e;

644

perror("write");

645

retval = -1;

795

646

goto mandos_end;

796

647

}

797

648

written += (size_t)ret;

805

656

break;

806

657

}

807

658

}

808

809

if(quit_now){

810

errno = EINTR;

811

goto mandos_end;

812

}

813

659

}

814

660

815

661

if(debug){

816

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

817

}

818

819

if(quit_now){

820

errno = EINTR;

821

goto mandos_end;

822

}

823

824

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

662

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

663

}

664

825

665

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

826

666

827

if(quit_now){

828

errno = EINTR;

829

goto mandos_end;

830

}

831

832

do {

667

do{

833

668

ret = gnutls_handshake(session);

834

if(quit_now){

835

errno = EINTR;

836

goto mandos_end;

837

}

838

669

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

839

670

840

671

if(ret != GNUTLS_E_SUCCESS){

841

672

if(debug){

842

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

673

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

843

674

gnutls_perror(ret);

844

675

}

845

errno = EPROTO;

676

retval = -1;

846

677

goto mandos_end;

847

678

}

848

679

849

680

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

850

681

851

682

if(debug){

852

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

853

" %s\n", ip);

683

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

684

ip);

854

685

}

855

686

856

687

while(true){

857

858

if(quit_now){

859

errno = EINTR;

860

goto mandos_end;

861

}

862

863

buffer_capacity = incbuffer(&buffer, buffer_length,

864

buffer_capacity);

688

buffer_capacity = adjustbuffer(&buffer, buffer_length,

689

buffer_capacity);

865

690

if(buffer_capacity == 0){

866

int e = errno;

867

perror_plus("incbuffer");

868

errno = e;

869

goto mandos_end;

870

}

871

872

if(quit_now){

873

errno = EINTR;

691

perror("adjustbuffer");

692

retval = -1;

874

693

goto mandos_end;

875

694

}

876

695

885

704

case GNUTLS_E_AGAIN:

886

705

break;

887

706

case GNUTLS_E_REHANDSHAKE:

888

do {

707

do{

889

708

ret = gnutls_handshake(session);

890

891

if(quit_now){

892

errno = EINTR;

893

goto mandos_end;

894

}

895

709

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

896

710

if(ret < 0){

897

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

898

"***\n");

711

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

899

712

gnutls_perror(ret);

900

errno = EPROTO;

713

retval = -1;

901

714

goto mandos_end;

902

715

}

903

716

break;

904

717

default:

905

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

906

" encrypted session with Mandos server\n");

718

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

719

" encrypted session with Mandos server\n");

720

retval = -1;

907

721

gnutls_bye(session, GNUTLS_SHUT_RDWR);

908

errno = EIO;

909

722

goto mandos_end;

910

723

}

911

724

} else {

914

727

}

915

728

916

729

if(debug){

917

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

918

}

919

920

if(quit_now){

921

errno = EINTR;

922

goto mandos_end;

923

}

924

925

do {

926

ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);

927

if(quit_now){

928

errno = EINTR;

929

goto mandos_end;

930

}

931

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

730

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

731

}

732

733

gnutls_bye(session, GNUTLS_SHUT_RDWR);

932

734

933

735

if(buffer_length > 0){

934

ssize_t decrypted_buffer_size;

935

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

736

decrypted_buffer_size = pgp_packet_decrypt(mc, buffer,

737

buffer_length,

936

738

&decrypted_buffer);

937

739

if(decrypted_buffer_size >= 0){

938

939

740

written = 0;

940

741

while(written < (size_t) decrypted_buffer_size){

941

if(quit_now){

942

errno = EINTR;

943

goto mandos_end;

944

}

945

946

742

ret = (int)fwrite(decrypted_buffer + written, 1,

947

743

(size_t)decrypted_buffer_size - written,

948

744

stdout);

949

745

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

950

int e = errno;

951

746

if(debug){

952

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

953

strerror(errno));

747

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

748

strerror(errno));

954

749

}

955

errno = e;

956

goto mandos_end;

750

retval = -1;

751

break;

957

752

}

958

753

written += (size_t)ret;

959

754

}

960

retval = 0;

755

free(decrypted_buffer);

756

} else {

757

retval = -1;

961

758

}

759

} else {

760

retval = -1;

962

761

}

963

762

964

763

/* Shutdown procedure */

965

764

966

765

mandos_end:

967

{

968

int e = errno;

969

free(decrypted_buffer);

970

free(buffer);

971

if(tcp_sd >= 0){

972

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

973

}

974

if(ret == -1){

975

if(e == 0){

976

e = errno;

977

}

978

perror_plus("close");

979

}

980

gnutls_deinit(session);

981

errno = e;

982

if(quit_now){

983

errno = EINTR;

984

retval = -1;

985

}

766

free(buffer);

767

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

768

if(ret == -1){

769

perror("close");

986

770

}

771

gnutls_deinit(session);

987

772

return retval;

988

773

}

989

774

1000

785

AVAHI_GCC_UNUSED AvahiStringList *txt,

1001

786

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1002

787

flags,

1003

AVAHI_GCC_UNUSED void* userdata){

788

void* userdata){

789

mandos_context *mc = userdata;

1004

790

assert(r);

1005

791

1006

792

/* Called whenever a service has been resolved successfully or

1007

793

timed out */

1008

794

1009

if(quit_now){

1010

return;

1011

}

1012

1013

795

switch(event){

1014

796

default:

1015

797

case AVAHI_RESOLVER_FAILURE:

1016

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

1017

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

1018

domain,

1019

avahi_strerror(avahi_server_errno(mc.server)));

798

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

799

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

800

avahi_strerror(avahi_server_errno(mc->server)));

1020

801

break;

1021

802

1022

803

case AVAHI_RESOLVER_FOUND:

1024

805

char ip[AVAHI_ADDRESS_STR_MAX];

1025

806

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

1026

807

if(debug){

1027

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

1028

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

1029

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

808

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

809

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

810

ip, (intmax_t)interface, port);

1030

811

}

1031

int ret = start_mandos_communication(ip, port, interface,

812

int ret = start_mandos_communication(ip, port, interface, mc,

1032

813

avahi_proto_to_af(proto));

1033

814

if(ret == 0){

1034

avahi_simple_poll_quit(mc.simple_poll);

1035

} else {

1036

if(not add_server(ip, port, interface,

1037

avahi_proto_to_af(proto))){

1038

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

1039

" list\n", name);

1040

}

815

avahi_simple_poll_quit(mc->simple_poll);

1041

816

}

1042

817

}

1043

818

}

1053

828

const char *domain,

1054

829

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1055

830

flags,

1056

AVAHI_GCC_UNUSED void* userdata){

831

void* userdata){

832

mandos_context *mc = userdata;

1057

833

assert(b);

1058

834

1059

835

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

1060

836

is removed from the LAN */

1061

837

1062

if(quit_now){

1063

return;

1064

}

1065

1066

838

switch(event){

1067

839

default:

1068

840

case AVAHI_BROWSER_FAILURE:

1069

841

1070

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

1071

avahi_strerror(avahi_server_errno(mc.server)));

1072

avahi_simple_poll_quit(mc.simple_poll);

842

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

843

avahi_strerror(avahi_server_errno(mc->server)));

844

avahi_simple_poll_quit(mc->simple_poll);

1073

845

return;

1074

846

1075

847

case AVAHI_BROWSER_NEW:

1078

850

the callback function is called the Avahi server will free the

1079

851

resolver for us. */

1080

852

1081

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

1082

name, type, domain, protocol, 0,

1083

resolve_callback, NULL) == NULL)

1084

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

1085

" %s\n", name,

1086

avahi_strerror(avahi_server_errno(mc.server)));

853

if(!(avahi_s_service_resolver_new(mc->server, interface,

854

protocol, name, type, domain,

855

AVAHI_PROTO_INET6, 0,

856

resolve_callback, mc)))

857

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

858

name, avahi_strerror(avahi_server_errno(mc->server)));

1087

859

break;

1088

860

1089

861

case AVAHI_BROWSER_REMOVE:

1092

864

case AVAHI_BROWSER_ALL_FOR_NOW:

1093

865

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1094

866

if(debug){

1095

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

1096

" searching...\n");

867

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

1097

868

}

1098

869

break;

1099

870

}

1100

871

}

1101

872

1102

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

1103

static void handle_sigterm(int sig){

1104

if(quit_now){

1105

return;

1106

}

1107

quit_now = 1;

1108

signal_received = sig;

1109

int old_errno = errno;

1110

/* set main loop to exit */

1111

if(mc.simple_poll != NULL){

1112

avahi_simple_poll_quit(mc.simple_poll);

1113

}

1114

errno = old_errno;

1115

}

1116

1117

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

1118

int ret;

1119

1120

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

1121

if(s < 0){

1122

perror_plus("socket");

1123

return false;

1124

}

1125

strcpy(ifr->ifr_name, ifname);

1126

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1127

if(ret == -1){

1128

if(debug){

1129

perror_plus("ioctl SIOCGIFFLAGS");

1130

}

1131

return false;

1132

}

1133

return true;

1134

}

1135

1136

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

1137

1138

/* Reject the loopback device */

1139

if(ifr->ifr_flags & IFF_LOOPBACK){

1140

if(debug){

1141

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

1142

ifname);

1143

}

1144

return false;

1145

}

1146

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

1147

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

1148

if(debug){

1149

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

1150

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

1151

}

1152

return true;

1153

}

1154

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

1155

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

1156

if(debug){

1157

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1158

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

1159

}

1160

return false;

1161

}

1162

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

1163

if(ifr->ifr_flags & IFF_NOARP){

1164

if(debug){

1165

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

1166

ifname);

1167

}

1168

return false;

1169

}

1170

1171

/* Accept this device */

1172

if(debug){

1173

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

1174

}

1175

return true;

1176

}

1177

1178

/*

1179

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

1180

* corresponds to an acceptable network device.

1181

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

1182

*/

1183

int good_interface(const struct dirent *if_entry){

1184

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

1185

return 0;

1186

}

1187

1188

struct ifreq ifr;

1189

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

1190

if(debug){

1191

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

1192

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

1193

}

1194

return 0;

1195

}

1196

1197

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

1198

return 0;

1199

}

1200

return 1;

1201

}

1202

1203

/*

1204

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

1205

* corresponds to an acceptable network device which is up.

1206

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

1207

*/

1208

int up_interface(const struct dirent *if_entry){

1209

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

1210

return 0;

1211

}

1212

1213

struct ifreq ifr;

1214

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

1215

if(debug){

1216

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

1217

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

1218

}

1219

return 0;

1220

}

1221

1222

/* Reject down interfaces */

1223

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

1224

if(debug){

1225

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

1226

if_entry->d_name);

1227

}

1228

return 0;

1229

}

1230

1231

/* Reject non-running interfaces */

1232

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

1233

if(debug){

1234

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

1235

if_entry->d_name);

1236

}

1237

return 0;

1238

}

1239

1240

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

1241

return 0;

1242

}

1243

return 1;

1244

}

1245

1246

int notdotentries(const struct dirent *direntry){

1247

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

1248

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

1249

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

1250

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

1251

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

1252

return 0;

1253

}

1254

return 1;

1255

}

1256

1257

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

1258

int runnable_hook(const struct dirent *direntry){

1259

int ret;

1260

size_t sret;

1261

struct stat st;

1262

1263

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

1264

/* Empty name? */

1265

return 0;

1266

}

1267

1268

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

1269

"abcdefghijklmnopqrstuvwxyz"

1270

"0123456789"

1271

"_-");

1272

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

1273

/* Contains non-allowed characters */

1274

if(debug){

1275

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

1276

direntry->d_name);

1277

}

1278

return 0;

1279

}

1280

1281

char *fullname = NULL;

1282

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

1283

if(ret < 0){

1284

perror_plus("asprintf");

1285

return 0;

1286

}

1287

1288

ret = stat(fullname, &st);

1289

if(ret == -1){

1290

if(debug){

1291

perror_plus("Could not stat hook");

1292

}

1293

return 0;

1294

}

1295

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

1296

/* Not a regular file */

1297

if(debug){

1298

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

1299

direntry->d_name);

1300

}

1301

return 0;

1302

}

1303

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

1304

/* Not executable */

1305

if(debug){

1306

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

1307

direntry->d_name);

1308

}

1309

return 0;

1310

}

1311

if(debug){

1312

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

1313

direntry->d_name);

1314

}

1315

return 1;

1316

}

1317

1318

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1319

int ret;

1320

struct timespec now;

1321

struct timespec waited_time;

1322

intmax_t block_time;

1323

1324

while(true){

1325

if(mc.current_server == NULL){

1326

if (debug){

1327

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

1328

" No timeout!\n");

1329

}

1330

ret = avahi_simple_poll_iterate(s, -1);

1331

} else {

1332

if (debug){

1333

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

1334

" it, or wait\n");

1335

}

1336

/* the current time */

1337

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1338

if(ret == -1){

1339

perror_plus("clock_gettime");

1340

return -1;

1341

}

1342

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

1343

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

1344

waited_time.tv_sec = (now.tv_sec

1345

- mc.current_server->last_seen.tv_sec);

1346

waited_time.tv_nsec = (now.tv_nsec

1347

- mc.current_server->last_seen.tv_nsec);

1348

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

1349

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

1350

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

1351

block_time = ((retry_interval

1352

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

1353

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

1354

1355

if (debug){

1356

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

1357

block_time);

1358

}

1359

1360

if(block_time <= 0){

1361

ret = start_mandos_communication(mc.current_server->ip,

1362

mc.current_server->port,

1363

mc.current_server->if_index,

1364

mc.current_server->af);

1365

if(ret == 0){

1366

avahi_simple_poll_quit(mc.simple_poll);

1367

return 0;

1368

}

1369

ret = clock_gettime(CLOCK_MONOTONIC,

1370

&mc.current_server->last_seen);

1371

if(ret == -1){

1372

perror_plus("clock_gettime");

1373

return -1;

1374

}

1375

mc.current_server = mc.current_server->next;

1376

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

1377

servers, but don't block */

1378

}

1379

1380

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

1381

}

1382

if(ret != 0){

1383

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

1384

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

1385

}

1386

}

1387

}

1388

}

1389

1390

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

1391

const float delay){

1392

struct dirent **direntries;

1393

struct dirent *direntry;

1394

int ret;

1395

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

1396

alphasort);

1397

if(numhooks == -1){

1398

perror_plus("scandir");

1399

} else {

1400

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

1401

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

1402

direntry = direntries[i];

1403

char *fullname = NULL;

1404

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

1405

if(ret < 0){

1406

perror_plus("asprintf");

1407

continue;

1408

}

1409

if(debug){

1410

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

1411

direntry->d_name);

1412

}

1413

pid_t hook_pid = fork();

1414

if(hook_pid == 0){

1415

/* Child */

1416

/* Raise privileges */

1417

errno = 0;

1418

ret = seteuid(0);

1419

if(ret == -1){

1420

perror_plus("seteuid");

1421

}

1422

/* Raise privileges even more */

1423

errno = 0;

1424

ret = setuid(0);

1425

if(ret == -1){

1426

perror_plus("setuid");

1427

}

1428

/* Set group */

1429

errno = 0;

1430

ret = setgid(0);

1431

if(ret == -1){

1432

perror_plus("setgid");

1433

}

1434

/* Reset supplementary groups */

1435

errno = 0;

1436

ret = setgroups(0, NULL);

1437

if(ret == -1){

1438

perror_plus("setgroups");

1439

}

1440

dup2(devnull, STDIN_FILENO);

1441

close(devnull);

1442

dup2(STDERR_FILENO, STDOUT_FILENO);

1443

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

1444

if(ret == -1){

1445

perror_plus("setenv");

1446

_exit(EX_OSERR);

1447

}

1448

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

1449

if(ret == -1){

1450

perror_plus("setenv");

1451

_exit(EX_OSERR);

1452

}

1453

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

1454

if(ret == -1){

1455

perror_plus("setenv");

1456

_exit(EX_OSERR);

1457

}

1458

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

1459

if(ret == -1){

1460

perror_plus("setenv");

1461

_exit(EX_OSERR);

1462

}

1463

char *delaystring;

1464

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

1465

if(ret == -1){

1466

perror_plus("asprintf");

1467

_exit(EX_OSERR);

1468

}

1469

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

1470

if(ret == -1){

1471

free(delaystring);

1472

perror_plus("setenv");

1473

_exit(EX_OSERR);

1474

}

1475

free(delaystring);

1476

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

1477

perror_plus("execl");

1478

_exit(EXIT_FAILURE);

1479

}

1480

} else {

1481

int status;

1482

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

1483

perror_plus("waitpid");

1484

free(fullname);

1485

continue;

1486

}

1487

if(WIFEXITED(status)){

1488

if(WEXITSTATUS(status) != 0){

1489

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

1490

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

1491

WEXITSTATUS(status));

1492

free(fullname);

1493

continue;

1494

}

1495

} else if(WIFSIGNALED(status)){

1496

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

1497

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

1498

WTERMSIG(status));

1499

free(fullname);

1500

continue;

1501

} else {

1502

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

1503

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

1504

free(fullname);

1505

continue;

1506

}

1507

}

1508

free(fullname);

1509

if(debug){

1510

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

1511

direntry->d_name);

1512

}

1513

}

1514

close(devnull);

1515

}

1516

return true;

1517

}

1518

1519

873

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

1520

874

AvahiSServiceBrowser *sb = NULL;

1521

875

int error;

1522

876

int ret;

1523

877

intmax_t tmpmax;

1524

char *tmp;

878

int numchars;

1525

879

int exitcode = EXIT_SUCCESS;

1526

const char *interface = "";

880

const char *interface = "eth0";

1527

881

struct ifreq network;

1528

int sd = -1;

1529

bool take_down_interface = false;

882

int sd;

1530

883

uid_t uid;

1531

884

gid_t gid;

885

char *connect_to = NULL;

1532

886

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

1533

887

bool tempdir_created = false;

1534

888

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1535

889

const char *seckey = PATHDIR "/" SECKEY;

1536

890

const char *pubkey = PATHDIR "/" PUBKEY;

1537

891

892

mandos_context mc = { .simple_poll = NULL, .server = NULL,

893

.dh_bits = 1024, .priority = "SECURE256"

894

":!CTYPE-X.509:+CTYPE-OPENPGP" };

1538

895

bool gnutls_initialized = false;

1539

896

bool gpgme_initialized = false;

1540

float delay = 2.5f;

1541

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

1542

retrying the same server again */

1543

1544

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1545

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1546

1547

uid = getuid();

1548

gid = getgid();

1549

1550

/* Lower any group privileges we might have, just to be safe */

1551

errno = 0;

1552

ret = setgid(gid);

1553

if(ret == -1){

1554

perror_plus("setgid");

1555

}

1556

1557

/* Lower user privileges (temporarily) */

1558

errno = 0;

1559

ret = seteuid(uid);

1560

if(ret == -1){

1561

perror_plus("seteuid");

1562

}

1563

1564

if(quit_now){

1565

goto end;

1566

}

897

double delay = 2.5;

1567

898

1568

899

{

1569

900

struct argp_option options[] = {

1599

930

.arg = "SECONDS",

1600

931

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

1601

932

.group = 2 },

1602

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

1603

.arg = "SECONDS",

1604

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

1605

.group = 2 },

1606

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

1607

.arg = "DIR",

1608

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

1609

.group = 2 },

1610

/*

1611

* These reproduce what we would get without ARGP_NO_HELP

1612

*/

1613

{ .name = "help", .key = '?',

1614

.doc = "Give this help list", .group = -1 },

1615

{ .name = "usage", .key = -3,

1616

.doc = "Give a short usage message", .group = -1 },

1617

{ .name = "version", .key = 'V',

1618

.doc = "Print program version", .group = -1 },

1619

933

{ .name = NULL }

1620

934

};

1621

935

1622

936

error_t parse_opt(int key, char *arg,

1623

937

struct argp_state *state){

1624

errno = 0;

1625

938

switch(key){

1626

939

case 128: /* --debug */

1627

940

debug = true;

1639

952

pubkey = arg;

1640

953

break;

1641

954

case 129: /* --dh-bits */

1642

errno = 0;

1643

tmpmax = strtoimax(arg, &tmp, 10);

1644

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

1645

or tmpmax != (typeof(mc.dh_bits))tmpmax){

1646

argp_error(state, "Bad number of DH bits");

955

ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);

956

if(ret < 1 or tmpmax != (typeof(mc.dh_bits))tmpmax

957

or arg[numchars] != '\0'){

958

fprintf(stderr, "Bad number of DH bits\n");

959

exit(EXIT_FAILURE);

1647

960

}

1648

961

mc.dh_bits = (typeof(mc.dh_bits))tmpmax;

1649

962

break;

1651

964

mc.priority = arg;

1652

965

break;

1653

966

case 131: /* --delay */

1654

errno = 0;

1655

delay = strtof(arg, &tmp);

1656

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

1657

argp_error(state, "Bad delay");

1658

}

1659

case 132: /* --retry */

1660

errno = 0;

1661

retry_interval = strtod(arg, &tmp);

1662

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

1663

or (retry_interval * 1000) > INT_MAX

1664

or retry_interval < 0){

1665

argp_error(state, "Bad retry interval");

1666

}

1667

break;

1668

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

1669

hookdir = arg;

1670

break;

1671

/*

1672

* These reproduce what we would get without ARGP_NO_HELP

1673

*/

1674

case '?': /* --help */

1675

argp_state_help(state, state->out_stream,

1676

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

1677

& ~(unsigned int)ARGP_HELP_EXIT_OK);

1678

case -3: /* --usage */

1679

argp_state_help(state, state->out_stream,

1680

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1681

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

1682

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

1683

exit(argp_err_exit_status);

967

ret = sscanf(arg, "%lf%n", &delay, &numchars);

968

if(ret < 1 or arg[numchars] != '\0'){

969

fprintf(stderr, "Bad delay\n");

970

exit(EXIT_FAILURE);

971

}

972

break;

973

case ARGP_KEY_ARG:

974

argp_usage(state);

975

case ARGP_KEY_END:

1684

976

break;

1685

977

default:

1686

978

return ARGP_ERR_UNKNOWN;

1687

979

}

1688

return errno;

980

return 0;

1689

981

}

1690

982

1691

983

struct argp argp = { .options = options, .parser = parse_opt,

1692

984

.args_doc = "",

1693

985

.doc = "Mandos client -- Get and decrypt"

1694

986

" passwords from a Mandos server" };

1695

ret = argp_parse(&argp, argc, argv,

1696

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1697

switch(ret){

1698

case 0:

1699

break;

1700

case ENOMEM:

1701

default:

1702

errno = ret;

1703

perror_plus("argp_parse");

1704

exitcode = EX_OSERR;

1705

goto end;

1706

case EINVAL:

1707

exitcode = EX_USAGE;

1708

goto end;

1709

}

1710

}

1711

1712

{

1713

/* Work around Debian bug #633582:

1714

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

1715

1716

/* Re-raise priviliges */

1717

errno = 0;

1718

ret = seteuid(0);

1719

if(ret == -1){

1720

perror_plus("seteuid");

1721

} else {

1722

struct stat st;

1723

1724

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

1725

int seckey_fd = open(seckey, O_RDONLY);

1726

if(seckey_fd == -1){

1727

perror_plus("open");

1728

} else {

1729

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

1730

if(ret == -1){

1731

perror_plus("fstat");

1732

} else {

1733

if(S_ISREG(st.st_mode)

1734

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

1735

ret = fchown(seckey_fd, uid, gid);

1736

if(ret == -1){

1737

perror_plus("fchown");

1738

}

1739

}

1740

}

1741

TEMP_FAILURE_RETRY(close(seckey_fd));

1742

}

1743

}

1744

1745

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

1746

int pubkey_fd = open(pubkey, O_RDONLY);

1747

if(pubkey_fd == -1){

1748

perror_plus("open");

1749

} else {

1750

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

1751

if(ret == -1){

1752

perror_plus("fstat");

1753

} else {

1754

if(S_ISREG(st.st_mode)

1755

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

1756

ret = fchown(pubkey_fd, uid, gid);

1757

if(ret == -1){

1758

perror_plus("fchown");

1759

}

1760

}

1761

}

1762

TEMP_FAILURE_RETRY(close(pubkey_fd));

1763

}

1764

}

1765

1766

/* Lower privileges */

1767

errno = 0;

1768

ret = seteuid(uid);

1769

if(ret == -1){

1770

perror_plus("seteuid");

1771

}

1772

}

1773

}

1774

1775

/* Run network hooks */

1776

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

1777

goto end;

1778

}

1779

1780

if(not debug){

1781

avahi_set_log_function(empty_log);

1782

}

1783

1784

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

1785

struct dirent **direntries;

1786

/* First look for interfaces that are up */

1787

ret = scandir(sys_class_net, &direntries, up_interface,

1788

alphasort);

1789

if(ret == 0){

1790

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

1791

free(direntries);

1792

ret = scandir(sys_class_net, &direntries, good_interface,

1793

alphasort);

1794

}

1795

if(ret >= 1){

1796

/* Pick the first interface returned */

1797

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

1798

if(debug){

1799

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

1800

}

1801

if(interface == NULL){

1802

perror_plus("malloc");

1803

free(direntries);

1804

exitcode = EXIT_FAILURE;

1805

goto end;

1806

}

1807

free(direntries);

1808

} else {

1809

free(direntries);

1810

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

987

ret = argp_parse(&argp, argc, argv, 0, 0, NULL);

988

if(ret == ARGP_ERR_UNKNOWN){

989

fprintf(stderr, "Unknown error while parsing arguments\n");

1811

990

exitcode = EXIT_FAILURE;

1812

991

goto end;

1813

992

}

1814

993

}

1815

994

1816

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

1817

from the signal handler */

1818

/* Initialize the pseudo-RNG for Avahi */

1819

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

1820

mc.simple_poll = avahi_simple_poll_new();

1821

if(mc.simple_poll == NULL){

1822

fprintf_plus(stderr,

1823

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

1824

exitcode = EX_UNAVAILABLE;

1825

goto end;

1826

}

1827

1828

sigemptyset(&sigterm_action.sa_mask);

1829

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

1830

if(ret == -1){

1831

perror_plus("sigaddset");

1832

exitcode = EX_OSERR;

1833

goto end;

1834

}

1835

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

1836

if(ret == -1){

1837

perror_plus("sigaddset");

1838

exitcode = EX_OSERR;

1839

goto end;

1840

}

1841

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

1842

if(ret == -1){

1843

perror_plus("sigaddset");

1844

exitcode = EX_OSERR;

1845

goto end;

1846

}

1847

/* Need to check if the handler is SIG_IGN before handling:

1848

| [[info:libc:Initial Signal Actions]] |

1849

| [[info:libc:Basic Signal Handling]] |

1850

*/

1851

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

1852

if(ret == -1){

1853

perror_plus("sigaction");

1854

return EX_OSERR;

1855

}

1856

if(old_sigterm_action.sa_handler != SIG_IGN){

1857

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

1858

if(ret == -1){

1859

perror_plus("sigaction");

1860

exitcode = EX_OSERR;

1861

goto end;

1862

}

1863

}

1864

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

1865

if(ret == -1){

1866

perror_plus("sigaction");

1867

return EX_OSERR;

1868

}

1869

if(old_sigterm_action.sa_handler != SIG_IGN){

1870

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

1871

if(ret == -1){

1872

perror_plus("sigaction");

1873

exitcode = EX_OSERR;

1874

goto end;

1875

}

1876

}

1877

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

1878

if(ret == -1){

1879

perror_plus("sigaction");

1880

return EX_OSERR;

1881

}

1882

if(old_sigterm_action.sa_handler != SIG_IGN){

1883

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

1884

if(ret == -1){

1885

perror_plus("sigaction");

1886

exitcode = EX_OSERR;

1887

goto end;

1888

}

1889

}

1890

1891

995

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

1892

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

1893

if_index = (AvahiIfIndex) if_nametoindex(interface);

1894

if(if_index == 0){

1895

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

1896

exitcode = EX_UNAVAILABLE;

1897

goto end;

1898

}

1899

1900

if(quit_now){

1901

goto end;

1902

}

1903

1904

/* Re-raise priviliges */

1905

errno = 0;

1906

ret = seteuid(0);

1907

if(ret == -1){

1908

perror_plus("seteuid");

1909

}

1910

996

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

1911

997

#ifdef __linux__

1912

998

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1913

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

999

messages to mess up the prompt */

1914

1000

ret = klogctl(8, NULL, 5);

1915

1001

bool restore_loglevel = true;

1916

1002

if(ret == -1){

1917

1003

restore_loglevel = false;

1918

perror_plus("klogctl");

1004

perror("klogctl");

1919

1005

}

1920

#endif /* __linux__ */

1006

#endif

1921

1007

1922

1008

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1923

1009

if(sd < 0){

1924

perror_plus("socket");

1925

exitcode = EX_OSERR;

1010

perror("socket");

1011

exitcode = EXIT_FAILURE;

1926

1012

#ifdef __linux__

1927

1013

if(restore_loglevel){

1928

1014

ret = klogctl(7, NULL, 0);

1929

1015

if(ret == -1){

1930

perror_plus("klogctl");

1016

perror("klogctl");

1931

1017

}

1932

1018

}

1933

#endif /* __linux__ */

1934

/* Lower privileges */

1935

errno = 0;

1936

ret = seteuid(uid);

1937

if(ret == -1){

1938

perror_plus("seteuid");

1939

}

1019

#endif

1940

1020

goto end;

1941

1021

}

1942

1022

strcpy(network.ifr_name, interface);

1943

1023

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

1944

1024

if(ret == -1){

1945

perror_plus("ioctl SIOCGIFFLAGS");

1025

perror("ioctl SIOCGIFFLAGS");

1946

1026

#ifdef __linux__

1947

1027

if(restore_loglevel){

1948

1028

ret = klogctl(7, NULL, 0);

1949

1029

if(ret == -1){

1950

perror_plus("klogctl");

1030

perror("klogctl");

1951

1031

}

1952

1032

}

1953

#endif /* __linux__ */

1954

exitcode = EX_OSERR;

1955

/* Lower privileges */

1956

errno = 0;

1957

ret = seteuid(uid);

1958

if(ret == -1){

1959

perror_plus("seteuid");

1960

}

1033

#endif

1034

exitcode = EXIT_FAILURE;

1961

1035

goto end;

1962

1036

}

1963

1037

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

1964

1038

network.ifr_flags |= IFF_UP;

1965

take_down_interface = true;

1966

1039

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

1967

1040

if(ret == -1){

1968

take_down_interface = false;

1969

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1970

exitcode = EX_OSERR;

1041

perror("ioctl SIOCSIFFLAGS");

1042

exitcode = EXIT_FAILURE;

1971

1043

#ifdef __linux__

1972

1044

if(restore_loglevel){

1973

1045

ret = klogctl(7, NULL, 0);

1974

1046

if(ret == -1){

1975

perror_plus("klogctl");

1047

perror("klogctl");

1976

1048

}

1977

1049

}

1978

#endif /* __linux__ */

1979

/* Lower privileges */

1980

errno = 0;

1981

ret = seteuid(uid);

1982

if(ret == -1){

1983

perror_plus("seteuid");

1984

}

1050

#endif

1985

1051

goto end;

1986

1052

}

1987

1053

}

1988

/* Sleep checking until interface is running.

1989

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

1054

/* sleep checking until interface is running */

1990

1055

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

1991

1056

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

1992

1057

if(ret == -1){

1993

perror_plus("ioctl SIOCGIFFLAGS");

1058

perror("ioctl SIOCGIFFLAGS");

1994

1059

} else if(network.ifr_flags & IFF_RUNNING){

1995

1060

break;

1996

1061

}

1997

1062

struct timespec sleeptime = { .tv_nsec = 250000000 };

1998

1063

ret = nanosleep(&sleeptime, NULL);

1999

1064

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

2000

perror_plus("nanosleep");

1065

perror("nanosleep");

2001

1066

}

2002

1067

}

2003

if(not take_down_interface){

2004

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

2005

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

2006

if(ret == -1){

2007

perror_plus("close");

2008

}

1068

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

1069

if(ret == -1){

1070

perror("close");

2009

1071

}

2010

1072

#ifdef __linux__

2011

1073

if(restore_loglevel){

2012

1074

/* Restores kernel loglevel to default */

2013

1075

ret = klogctl(7, NULL, 0);

2014

1076

if(ret == -1){

2015

perror_plus("klogctl");

1077

perror("klogctl");

2016

1078

}

2017

1079

}

2018

#endif /* __linux__ */

2019

/* Lower privileges */

2020

errno = 0;

2021

/* Lower privileges */

2022

ret = seteuid(uid);

2023

if(ret == -1){

2024

perror_plus("seteuid");

2025

}

2026

}

2027

2028

if(quit_now){

2029

goto end;

2030

}

2031

2032

ret = init_gnutls_global(pubkey, seckey);

2033

if(ret == -1){

2034

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

2035

exitcode = EX_UNAVAILABLE;

1080

#endif

1081

}

1082

1083

uid = getuid();

1084

gid = getgid();

1085

1086

errno = 0;

1087

setgid(gid);

1088

if(ret == -1){

1089

perror("setgid");

1090

}

1091

1092

ret = setuid(uid);

1093

if(ret == -1){

1094

perror("setuid");

1095

}

1096

1097

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

1098

if(ret == -1){

1099

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

1100

exitcode = EXIT_FAILURE;

2036

1101

goto end;

2037

1102

} else {

2038

1103

gnutls_initialized = true;

2039

1104

}

2040

1105

2041

if(quit_now){

2042

goto end;

2043

}

2044

2045

1106

if(mkdtemp(tempdir) == NULL){

2046

perror_plus("mkdtemp");

1107

perror("mkdtemp");

2047

1108

goto end;

2048

1109

}

2049

1110

tempdir_created = true;

2050

1111

2051

if(quit_now){

2052

goto end;

2053

}

2054

2055

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

2056

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

2057

exitcode = EX_UNAVAILABLE;

1112

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

1113

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

1114

exitcode = EXIT_FAILURE;

2058

1115

goto end;

2059

1116

} else {

2060

1117

gpgme_initialized = true;

2061

1118

}

2062

1119

2063

if(quit_now){

2064

goto end;

1120

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

1121

if_index = (AvahiIfIndex) if_nametoindex(interface);

1122

if(if_index == 0){

1123

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

1124

exitcode = EXIT_FAILURE;

1125

goto end;

1126

}

2065

1127

}

2066

1128

2067

1129

if(connect_to != NULL){

2069

1131

/* (Mainly meant for debugging) */

2070

1132

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

2071

1133

if(address == NULL){

2072

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

2073

exitcode = EX_USAGE;

2074

goto end;

2075

}

2076

2077

if(quit_now){

2078

goto end;

2079

}

2080

1134

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

1135

exitcode = EXIT_FAILURE;

1136

goto end;

1137

}

2081

1138

uint16_t port;

2082

errno = 0;

2083

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

2084

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

2085

or tmpmax != (uint16_t)tmpmax){

2086

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

2087

exitcode = EX_USAGE;

2088

goto end;

2089

}

2090

2091

if(quit_now){

2092

goto end;

2093

}

2094

1139

ret = sscanf(address+1, "%" SCNdMAX "%n", &tmpmax, &numchars);

1140

if(ret < 1 or tmpmax != (uint16_t)tmpmax

1141

or address[numchars+1] != '\0'){

1142

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

1143

exitcode = EXIT_FAILURE;

1144

goto end;

1145

}

2095

1146

port = (uint16_t)tmpmax;

2096

1147

*address = '\0';

1148

address = connect_to;

2097

1149

/* Colon in address indicates IPv6 */

2098

1150

int af;

2099

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

1151

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

2100

1152

af = AF_INET6;

2101

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

2102

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

2103

{

2104

connect_to++;

2105

address[-1] = '\0';

2106

}

2107

1153

} else {

2108

1154

af = AF_INET;

2109

1155

}

2110

address = connect_to;

2111

2112

if(quit_now){

2113

goto end;

2114

}

2115

2116

while(not quit_now){

2117

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

2118

if(quit_now or ret == 0){

2119

break;

2120

}

2121

if(debug){

2122

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

2123

(int)retry_interval);

2124

}

2125

sleep((int)retry_interval);

2126

}

2127

2128

if (not quit_now){

1156

ret = start_mandos_communication(address, port, if_index, &mc,

1157

af);

1158

if(ret < 0){

1159

exitcode = EXIT_FAILURE;

1160

} else {

2129

1161

exitcode = EXIT_SUCCESS;

2130

1162

}

2131

2132

1163

goto end;

2133

1164

}

2134

1165

2135

if(quit_now){

1166

if(not debug){

1167

avahi_set_log_function(empty_log);

1168

}

1169

1170

/* Initialize the pseudo-RNG for Avahi */

1171

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

1172

1173

/* Allocate main Avahi loop object */

1174

mc.simple_poll = avahi_simple_poll_new();

1175

if(mc.simple_poll == NULL){

1176

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

1177

exitcode = EXIT_FAILURE;

2136

1178

goto end;

2137

1179

}

2138

1180

2156

1198

2157

1199

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

2158

1200

if(mc.server == NULL){

2159

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

2160

avahi_strerror(error));

2161

exitcode = EX_UNAVAILABLE;

2162

goto end;

2163

}

2164

2165

if(quit_now){

1201

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

1202

avahi_strerror(error));

1203

exitcode = EXIT_FAILURE;

2166

1204

goto end;

2167

1205

}

2168

1206

2169

1207

/* Create the Avahi service browser */

2170

1208

sb = avahi_s_service_browser_new(mc.server, if_index,

2171

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2172

NULL, 0, browse_callback, NULL);

1209

AVAHI_PROTO_INET6, "_mandos._tcp",

1210

NULL, 0, browse_callback, &mc);

2173

1211

if(sb == NULL){

2174

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

2175

avahi_strerror(avahi_server_errno(mc.server)));

2176

exitcode = EX_UNAVAILABLE;

2177

goto end;

2178

}

2179

2180

if(quit_now){

1212

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

1213

avahi_strerror(avahi_server_errno(mc.server)));

1214

exitcode = EXIT_FAILURE;

2181

1215

goto end;

2182

1216

}

2183

1217

2184

1218

/* Run the main loop */

2185

1219

2186

1220

if(debug){

2187

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

2188

}

2189

2190

ret = avahi_loop_with_timeout(mc.simple_poll,

2191

(int)(retry_interval * 1000));

2192

if(debug){

2193

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

2194

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

2195

}

1221

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

1222

}

1223

1224

avahi_simple_poll_loop(mc.simple_poll);

2196

1225

2197

1226

end:

2198

1227

2199

1228

if(debug){

2200

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

1229

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

2201

1230

}

2202

1231

2203

1232

/* Cleanup things */

2220

1249

gpgme_release(mc.ctx);

2221

1250

}

2222

1251

2223

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

2224

has seen */

2225

if(mc.current_server != NULL){

2226

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

2227

while(mc.current_server != NULL){

2228

server *next = mc.current_server->next;

2229

free(mc.current_server);

2230

mc.current_server = next;

2231

}

2232

}

2233

2234

/* Run network hooks */

2235

run_network_hooks("stop", interface, delay);

2236

2237

/* Re-raise priviliges */

2238

{

2239

errno = 0;

2240

ret = seteuid(0);

2241

if(ret == -1){

2242

perror_plus("seteuid");

2243

}

2244

2245

/* Take down the network interface */

2246

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

2247

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

2248

if(ret == -1){

2249

perror_plus("ioctl SIOCGIFFLAGS");

2250

} else if(network.ifr_flags & IFF_UP){

2251

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

2252

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

2253

if(ret == -1){

2254

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2255

}

2256

}

2257

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

2258

if(ret == -1){

2259

perror_plus("close");

2260

}

2261

}

2262

}

2263

/* Lower privileges permanently */

2264

errno = 0;

2265

ret = setuid(uid);

2266

if(ret == -1){

2267

perror_plus("setuid");

2268

}

2269

2270

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

1252

/* Removes the temp directory used by GPGME */

2271

1253

if(tempdir_created){

2272

struct dirent **direntries = NULL;

2273

struct dirent *direntry = NULL;

2274

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

2275

alphasort);

2276

if (numentries > 0){

2277

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

2278

direntry = direntries[i];

1254

DIR *d;

1255

struct dirent *direntry;

1256

d = opendir(tempdir);

1257

if(d == NULL){

1258

if(errno != ENOENT){

1259

perror("opendir");

1260

}

1261

} else {

1262

while(true){

1263

direntry = readdir(d);

1264

if(direntry == NULL){

1265

break;

1266

}

1267

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

1268

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

1269

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

1270

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

1271

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

1272

continue;

1273

}

2279

1274

char *fullname = NULL;

2280

1275

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

2281

1276

direntry->d_name);

2282

1277

if(ret < 0){

2283

perror_plus("asprintf");

1278

perror("asprintf");

2284

1279

continue;

2285

1280

}

2286

1281

ret = remove(fullname);

2287

1282

if(ret == -1){

2288

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

2289

strerror(errno));

1283

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

1284

strerror(errno));

2290

1285

}

2291

1286

free(fullname);

2292

1287

}

2293

}

2294

2295

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

2296

free(direntries);

2297

if (numentries == -1){

2298

perror_plus("scandir");

1288

closedir(d);

2299

1289

}

2300

1290

ret = rmdir(tempdir);

2301

1291

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

2302

perror_plus("rmdir");

2303

}

2304

}

2305

2306

if(quit_now){

2307

sigemptyset(&old_sigterm_action.sa_mask);

2308

old_sigterm_action.sa_handler = SIG_DFL;

2309

ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,

2310

&old_sigterm_action,

2311

NULL));

2312

if(ret == -1){

2313

perror_plus("sigaction");

2314

}

2315

do {

2316

ret = raise(signal_received);

2317

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

2318

if(ret != 0){

2319

perror_plus("raise");

2320

abort();

2321

}

2322

TEMP_FAILURE_RETRY(pause());

1292

perror("rmdir");

1293

}

2323

1294

}

2324

1295

2325

1296

return exitcode;