/mandos/release : revision 237.7.140

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

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*

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* Everything else is

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*

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

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

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* along with this program. If not, see

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

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*

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

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

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*/

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

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#ifndef _LARGEFILE_SOURCE

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#define _LARGEFILE_SOURCE

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#endif

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#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(), sscanf(),

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remove() */

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

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stdout, ferror(), remove() */

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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, EXIT_FAILURE,

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srand() */

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

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strtof(), abort() */

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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() */

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

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*/

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

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

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strtoimax() */

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

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

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

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

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program_invocation_short_name */

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

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

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SIOCSIFFLAGS, if_indextoname(),

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if_nametoindex(), IF_NAMESIZE */

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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(), setuid(),

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setgid() */

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

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

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

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

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#include <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, sigaction,

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sig_atomic_t */

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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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93

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

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111

init_gnutls_session(),

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112

GNUTLS_* */

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113

#include <gnutls/openpgp.h>

104

/* 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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116

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/* GPGME */

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

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126

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

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127

#define SECKEY "seckey.txt"

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128

#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@fukt.bsnet.se>";

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

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

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char *connect_to = NULL;

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const char *hookdir = HOOKDIR;

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139

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

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151

typedef struct {

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156

gnutls_dh_params_t dh_params;

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const char *priority;

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gpgme_ctx_t ctx;

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server *current_server;

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160

} mandos_context;

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161

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

137

mandos_context mc;

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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: ",

175

program_invocation_short_name);

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errno = e;

177

perror(print_text);

178

}

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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

}

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189

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190

/*

140

191

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

142

193

* "buffer_length" is how much is already used.

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194

*/

144

195

size_t incbuffer(char **buffer, size_t buffer_length,

145

size_t buffer_capacity){

196

size_t buffer_capacity){

146

197

if(buffer_length + BUFFER_SIZE > buffer_capacity){

147

198

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

148

199

if(buffer == NULL){

153

204

return buffer_capacity;

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205

}

155

206

207

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

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

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int af){

210

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 };

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if(new_server->ip == NULL){

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perror_plus("strdup");

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return false;

223

}

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/* Special case of first server */

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if (mc.current_server == NULL){

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new_server->next = new_server;

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new_server->prev = new_server;

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mc.current_server = new_server;

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

230

} else {

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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

156

244

/*

157

245

* Initialize GPGME.

158

246

*/

159

static bool init_gpgme(const char *seckey,

160

const char *pubkey, const char *tempdir){

161

int ret;

247

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

248

const char *tempdir){

162

249

gpgme_error_t rc;

163

250

gpgme_engine_info_t engine_info;

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251

167

254

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

168

255

*/

169

256

bool import_key(const char *filename){

257

int ret;

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int fd;

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259

gpgme_data_t pgp_data;

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

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262

if(fd == -1){

175

perror("open");

263

perror_plus("open");

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264

return false;

177

265

}

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266

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rc = gpgme_data_new_from_fd(&pgp_data, fd);

180

268

if(rc != GPG_ERR_NO_ERROR){

181

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

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272

}

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273

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rc = gpgme_op_import(mc.ctx, pgp_data);

187

275

if(rc != GPG_ERR_NO_ERROR){

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

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279

}

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

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282

if(ret == -1){

195

perror("close");

283

perror_plus("close");

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}

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gpgme_data_release(pgp_data);

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return true;

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287

}

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if(debug){

202

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

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

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291

}

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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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296

if(rc != GPG_ERR_NO_ERROR){

209

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

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gpgme_strsource(rc), gpgme_strerror(rc));

297

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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300

}

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301

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

302

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

215

303

rc = gpgme_get_engine_info(&engine_info);

216

304

if(rc != GPG_ERR_NO_ERROR){

217

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

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gpgme_strsource(rc), gpgme_strerror(rc));

305

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

306

gpgme_strsource(rc), gpgme_strerror(rc));

219

307

return false;

220

308

}

221

309

while(engine_info != NULL){

227

315

engine_info = engine_info->next;

228

316

}

229

317

if(engine_info == NULL){

230

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

318

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

319

tempdir);

231

320

return false;

232

321

}

233

322

234

323

/* Create new GPGME "context" */

235

324

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

236

325

if(rc != GPG_ERR_NO_ERROR){

237

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

238

gpgme_strsource(rc), gpgme_strerror(rc));

326

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

327

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

328

gpgme_strerror(rc));

239

329

return false;

240

330

}

241

331

243

333

return false;

244

334

}

245

335

246

return true;

336

return true;

247

337

}

248

338

249

339

/*

260

350

ssize_t plaintext_length = 0;

261

351

262

352

if(debug){

263

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

353

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

264

354

}

265

355

266

356

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

267

357

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

268

358

0);

269

359

if(rc != GPG_ERR_NO_ERROR){

270

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

271

gpgme_strsource(rc), gpgme_strerror(rc));

360

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

361

gpgme_strsource(rc), gpgme_strerror(rc));

272

362

return -1;

273

363

}

274

364

275

365

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

276

366

rc = gpgme_data_new(&dh_plain);

277

367

if(rc != GPG_ERR_NO_ERROR){

278

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

279

gpgme_strsource(rc), gpgme_strerror(rc));

368

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

369

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

370

gpgme_strsource(rc), gpgme_strerror(rc));

280

371

gpgme_data_release(dh_crypto);

281

372

return -1;

282

373

}

285

376

data buffer */

286

377

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

287

378

if(rc != GPG_ERR_NO_ERROR){

288

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

289

gpgme_strsource(rc), gpgme_strerror(rc));

379

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

380

gpgme_strsource(rc), gpgme_strerror(rc));

290

381

plaintext_length = -1;

291

382

if(debug){

292

383

gpgme_decrypt_result_t result;

293

384

result = gpgme_op_decrypt_result(mc.ctx);

294

385

if(result == NULL){

295

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

386

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

296

387

} else {

297

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

298

result->unsupported_algorithm);

299

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

300

result->wrong_key_usage);

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);

301

392

if(result->file_name != NULL){

302

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

393

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

303

394

}

304

395

gpgme_recipient_t recipient;

305

396

recipient = result->recipients;

306

if(recipient){

307

while(recipient != NULL){

308

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

309

gpgme_pubkey_algo_name(recipient->pubkey_algo));

310

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

311

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

312

recipient->status == GPG_ERR_NO_SECKEY

313

? "No" : "Yes");

314

recipient = recipient->next;

315

}

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;

316

406

}

317

407

}

318

408

}

320

410

}

321

411

322

412

if(debug){

323

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

413

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

324

414

}

325

415

326

416

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

327

417

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

328

perror("gpgme_data_seek");

418

perror_plus("gpgme_data_seek");

329

419

plaintext_length = -1;

330

420

goto decrypt_end;

331

421

}

333

423

*plaintext = NULL;

334

424

while(true){

335

425

plaintext_capacity = incbuffer(plaintext,

336

(size_t)plaintext_length,

337

plaintext_capacity);

426

(size_t)plaintext_length,

427

plaintext_capacity);

338

428

if(plaintext_capacity == 0){

339

perror("incbuffer");

340

plaintext_length = -1;

341

goto decrypt_end;

429

perror_plus("incbuffer");

430

plaintext_length = -1;

431

goto decrypt_end;

342

432

}

343

433

344

434

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

349

439

break;

350

440

}

351

441

if(ret < 0){

352

perror("gpgme_data_read");

442

perror_plus("gpgme_data_read");

353

443

plaintext_length = -1;

354

444

goto decrypt_end;

355

445

}

357

447

}

358

448

359

449

if(debug){

360

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

450

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

361

451

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

362

452

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

363

453

}

385

475

/* GnuTLS log function callback */

386

476

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

387

477

const char* string){

388

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

478

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

389

479

}

390

480

391

481

static int init_gnutls_global(const char *pubkeyfilename,

393

483

int ret;

394

484

395

485

if(debug){

396

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

486

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

397

487

}

398

488

399

489

ret = gnutls_global_init();

400

490

if(ret != GNUTLS_E_SUCCESS){

401

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

402

safer_gnutls_strerror(ret));

491

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

492

safer_gnutls_strerror(ret));

403

493

return -1;

404

494

}

405

495

412

502

}

413

503

414

504

/* OpenPGP credentials */

415

gnutls_certificate_allocate_credentials(&mc.cred);

505

ret = gnutls_certificate_allocate_credentials(&mc.cred);

416

506

if(ret != GNUTLS_E_SUCCESS){

417

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

418

from

419

-Wunreachable-code

420

*/

421

safer_gnutls_strerror(ret));

507

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

508

safer_gnutls_strerror(ret));

422

509

gnutls_global_deinit();

423

510

return -1;

424

511

}

425

512

426

513

if(debug){

427

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

428

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

429

seckeyfilename);

514

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

515

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

516

pubkeyfilename,

517

seckeyfilename);

430

518

}

431

519

432

520

ret = gnutls_certificate_set_openpgp_key_file

433

521

(mc.cred, pubkeyfilename, seckeyfilename,

434

522

GNUTLS_OPENPGP_FMT_BASE64);

435

523

if(ret != GNUTLS_E_SUCCESS){

436

fprintf(stderr,

437

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

438

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

439

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

440

safer_gnutls_strerror(ret));

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));

441

529

goto globalfail;

442

530

}

443

531

444

532

/* GnuTLS server initialization */

445

533

ret = gnutls_dh_params_init(&mc.dh_params);

446

534

if(ret != GNUTLS_E_SUCCESS){

447

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

448

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

535

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

536

" initialization: %s\n",

537

safer_gnutls_strerror(ret));

449

538

goto globalfail;

450

539

}

451

540

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

452

541

if(ret != GNUTLS_E_SUCCESS){

453

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

454

safer_gnutls_strerror(ret));

542

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

543

safer_gnutls_strerror(ret));

455

544

goto globalfail;

456

545

}

457

546

470

559

static int init_gnutls_session(gnutls_session_t *session){

471

560

int ret;

472

561

/* GnuTLS session creation */

473

ret = gnutls_init(session, GNUTLS_SERVER);

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);

474

568

if(ret != GNUTLS_E_SUCCESS){

475

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

476

safer_gnutls_strerror(ret));

569

fprintf_plus(stderr,

570

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

571

safer_gnutls_strerror(ret));

477

572

}

478

573

479

574

{

480

575

const char *err;

481

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

482

583

if(ret != GNUTLS_E_SUCCESS){

483

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

484

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

485

safer_gnutls_strerror(ret));

584

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

585

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

586

safer_gnutls_strerror(ret));

486

587

gnutls_deinit(*session);

487

588

return -1;

488

589

}

489

590

}

490

591

491

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

492

mc.cred);

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);

493

600

if(ret != GNUTLS_E_SUCCESS){

494

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

495

safer_gnutls_strerror(ret));

601

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

602

safer_gnutls_strerror(ret));

496

603

gnutls_deinit(*session);

497

604

return -1;

498

605

}

499

606

500

607

/* ignore client certificate if any. */

501

gnutls_certificate_server_set_request(*session,

502

GNUTLS_CERT_IGNORE);

608

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

503

609

504

610

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

505

611

514

620

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

515

621

AvahiIfIndex if_index,

516

622

int af){

517

int ret, tcp_sd;

623

int ret, tcp_sd = -1;

518

624

ssize_t sret;

519

625

union {

520

626

struct sockaddr_in in;

521

627

struct sockaddr_in6 in6;

522

628

} to;

523

629

char *buffer = NULL;

524

char *decrypted_buffer;

630

char *decrypted_buffer = NULL;

525

631

size_t buffer_length = 0;

526

632

size_t buffer_capacity = 0;

527

ssize_t decrypted_buffer_size;

528

633

size_t written;

529

int retval = 0;

634

int retval = -1;

530

635

gnutls_session_t session;

531

636

int pf; /* Protocol family */

532

637

638

errno = 0;

639

640

if(quit_now){

641

errno = EINTR;

642

return -1;

643

}

644

533

645

switch(af){

534

646

case AF_INET6:

535

647

pf = PF_INET6;

538

650

pf = PF_INET;

539

651

break;

540

652

default:

541

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

653

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

654

errno = EINVAL;

542

655

return -1;

543

656

}

544

657

548

661

}

549

662

550

663

if(debug){

551

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

552

"\n", ip, port);

664

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

665

PRIu16 "\n", ip, port);

553

666

}

554

667

555

668

tcp_sd = socket(pf, SOCK_STREAM, 0);

556

669

if(tcp_sd < 0){

557

perror("socket");

558

return -1;

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;

559

679

}

560

680

561

681

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

562

682

if(af == AF_INET6){

563

to.in6.sin6_family = (uint16_t)af;

683

to.in6.sin6_family = (sa_family_t)af;

564

684

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

565

685

} else { /* IPv4 */

566

686

to.in.sin_family = (sa_family_t)af;

567

687

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

568

688

}

569

689

if(ret < 0 ){

570

perror("inet_pton");

571

return -1;

690

int e = errno;

691

perror_plus("inet_pton");

692

errno = e;

693

goto mandos_end;

572

694

}

573

695

if(ret == 0){

574

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

575

return -1;

696

int e = errno;

697

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

698

errno = e;

699

goto mandos_end;

576

700

}

577

701

if(af == AF_INET6){

578

702

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

581

705

582

706

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

583

707

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

584

-Wunreachable-code*/

708

-Wunreachable-code*/

585

709

if(if_index == AVAHI_IF_UNSPEC){

586

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

587

" without a network interface\n");

588

return -1;

710

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

711

" incomplete without a network interface\n");

712

errno = EINVAL;

713

goto mandos_end;

589

714

}

590

715

/* Set the network interface number as scope */

591

716

to.in6.sin6_scope_id = (uint32_t)if_index;

596

721

-Wunreachable-code */

597

722

}

598

723

724

if(quit_now){

725

errno = EINTR;

726

goto mandos_end;

727

}

728

599

729

if(debug){

600

730

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

601

731

char interface[IF_NAMESIZE];

602

732

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

603

perror("if_indextoname");

733

perror_plus("if_indextoname");

604

734

} else {

605

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

606

ip, interface, port);

735

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

736

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

607

737

}

608

738

} else {

609

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

610

port);

739

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

740

ip, port);

611

741

}

612

742

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

613

743

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

620

750

sizeof(addrstr));

621

751

}

622

752

if(pcret == NULL){

623

perror("inet_ntop");

753

perror_plus("inet_ntop");

624

754

} else {

625

755

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

626

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

756

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

627

757

}

628

758

}

629

759

}

630

760

761

if(quit_now){

762

errno = EINTR;

763

goto mandos_end;

764

}

765

631

766

if(af == AF_INET6){

632

767

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

633

768

} else {

634

769

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

635

770

}

636

771

if(ret < 0){

637

perror("connect");

638

return -1;

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;

639

783

}

640

784

641

785

const char *out = mandos_protocol_version;

643

787

while(true){

644

788

size_t out_size = strlen(out);

645

789

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

646

out_size - written));

790

out_size - written));

647

791

if(ret == -1){

648

perror("write");

649

retval = -1;

792

int e = errno;

793

perror_plus("write");

794

errno = e;

650

795

goto mandos_end;

651

796

}

652

797

written += (size_t)ret;

660

805

break;

661

806

}

662

807

}

808

809

if(quit_now){

810

errno = EINTR;

811

goto mandos_end;

812

}

663

813

}

664

814

665

815

if(debug){

666

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

667

}

668

669

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

670

671

do{

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

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

825

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

826

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

827

gnutls_transport_set_ptr(session,

828

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

829

830

if(quit_now){

831

errno = EINTR;

832

goto mandos_end;

833

}

834

835

do {

672

836

ret = gnutls_handshake(session);

837

if(quit_now){

838

errno = EINTR;

839

goto mandos_end;

840

}

673

841

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

674

842

675

843

if(ret != GNUTLS_E_SUCCESS){

676

844

if(debug){

677

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

845

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

678

846

gnutls_perror(ret);

679

847

}

680

retval = -1;

848

errno = EPROTO;

681

849

goto mandos_end;

682

850

}

683

851

684

852

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

685

853

686

854

if(debug){

687

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

688

ip);

855

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

856

" %s\n", ip);

689

857

}

690

858

691

859

while(true){

860

861

if(quit_now){

862

errno = EINTR;

863

goto mandos_end;

864

}

865

692

866

buffer_capacity = incbuffer(&buffer, buffer_length,

693

buffer_capacity);

867

buffer_capacity);

694

868

if(buffer_capacity == 0){

695

perror("incbuffer");

696

retval = -1;

869

int e = errno;

870

perror_plus("incbuffer");

871

errno = e;

872

goto mandos_end;

873

}

874

875

if(quit_now){

876

errno = EINTR;

697

877

goto mandos_end;

698

878

}

699

879

708

888

case GNUTLS_E_AGAIN:

709

889

break;

710

890

case GNUTLS_E_REHANDSHAKE:

711

do{

891

do {

712

892

ret = gnutls_handshake(session);

893

894

if(quit_now){

895

errno = EINTR;

896

goto mandos_end;

897

}

713

898

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

714

899

if(ret < 0){

715

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

900

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

901

"***\n");

716

902

gnutls_perror(ret);

717

retval = -1;

903

errno = EPROTO;

718

904

goto mandos_end;

719

905

}

720

906

break;

721

907

default:

722

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

723

" encrypted session with Mandos server\n");

724

retval = -1;

908

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

909

" encrypted session with Mandos server\n");

725

910

gnutls_bye(session, GNUTLS_SHUT_RDWR);

911

errno = EIO;

726

912

goto mandos_end;

727

913

}

728

914

} else {

731

917

}

732

918

733

919

if(debug){

734

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

735

}

736

737

gnutls_bye(session, GNUTLS_SHUT_RDWR);

920

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

921

}

922

923

if(quit_now){

924

errno = EINTR;

925

goto mandos_end;

926

}

927

928

do {

929

ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);

930

if(quit_now){

931

errno = EINTR;

932

goto mandos_end;

933

}

934

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

738

935

739

936

if(buffer_length > 0){

740

decrypted_buffer_size = pgp_packet_decrypt(buffer,

741

buffer_length,

937

ssize_t decrypted_buffer_size;

938

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

742

939

&decrypted_buffer);

743

940

if(decrypted_buffer_size >= 0){

941

744

942

written = 0;

745

943

while(written < (size_t) decrypted_buffer_size){

944

if(quit_now){

945

errno = EINTR;

946

goto mandos_end;

947

}

948

746

949

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

747

950

(size_t)decrypted_buffer_size - written,

748

951

stdout);

749

952

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

953

int e = errno;

750

954

if(debug){

751

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

752

strerror(errno));

955

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

956

strerror(errno));

753

957

}

754

retval = -1;

755

break;

958

errno = e;

959

goto mandos_end;

756

960

}

757

961

written += (size_t)ret;

758

962

}

759

free(decrypted_buffer);

760

} else {

761

retval = -1;

963

retval = 0;

762

964

}

763

} else {

764

retval = -1;

765

965

}

766

966

767

967

/* Shutdown procedure */

768

968

769

969

mandos_end:

770

free(buffer);

771

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

772

if(ret == -1){

773

perror("close");

970

{

971

int e = errno;

972

free(decrypted_buffer);

973

free(buffer);

974

if(tcp_sd >= 0){

975

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

976

}

977

if(ret == -1){

978

if(e == 0){

979

e = errno;

980

}

981

perror_plus("close");

982

}

983

gnutls_deinit(session);

984

errno = e;

985

if(quit_now){

986

errno = EINTR;

987

retval = -1;

988

}

774

989

}

775

gnutls_deinit(session);

776

990

return retval;

777

991

}

778

992

795

1009

/* Called whenever a service has been resolved successfully or

796

1010

timed out */

797

1011

1012

if(quit_now){

1013

return;

1014

}

1015

798

1016

switch(event){

799

1017

default:

800

1018

case AVAHI_RESOLVER_FAILURE:

801

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

802

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

803

avahi_strerror(avahi_server_errno(mc.server)));

1019

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

1020

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

1021

domain,

1022

avahi_strerror(avahi_server_errno(mc.server)));

804

1023

break;

805

1024

806

1025

case AVAHI_RESOLVER_FOUND:

808

1027

char ip[AVAHI_ADDRESS_STR_MAX];

809

1028

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

810

1029

if(debug){

811

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

812

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

813

ip, (intmax_t)interface, port);

1030

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

1031

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

1032

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

814

1033

}

815

1034

int ret = start_mandos_communication(ip, port, interface,

816

1035

avahi_proto_to_af(proto));

817

1036

if(ret == 0){

818

1037

avahi_simple_poll_quit(mc.simple_poll);

1038

} else {

1039

if(not add_server(ip, port, interface,

1040

avahi_proto_to_af(proto))){

1041

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

1042

" list\n", name);

1043

}

819

1044

}

820

1045

}

821

1046

}

837

1062

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

838

1063

is removed from the LAN */

839

1064

1065

if(quit_now){

1066

return;

1067

}

1068

840

1069

switch(event){

841

1070

default:

842

1071

case AVAHI_BROWSER_FAILURE:

843

1072

844

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

845

avahi_strerror(avahi_server_errno(mc.server)));

1073

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

1074

avahi_strerror(avahi_server_errno(mc.server)));

846

1075

avahi_simple_poll_quit(mc.simple_poll);

847

1076

return;

848

1077

852

1081

the callback function is called the Avahi server will free the

853

1082

resolver for us. */

854

1083

855

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

856

protocol, name, type, domain,

857

AVAHI_PROTO_INET6, 0,

858

resolve_callback, NULL)))

859

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

860

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

1084

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

1085

name, type, domain, protocol, 0,

1086

resolve_callback, NULL) == NULL)

1087

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

1088

" %s\n", name,

1089

avahi_strerror(avahi_server_errno(mc.server)));

861

1090

break;

862

1091

863

1092

case AVAHI_BROWSER_REMOVE:

866

1095

case AVAHI_BROWSER_ALL_FOR_NOW:

867

1096

case AVAHI_BROWSER_CACHE_EXHAUSTED:

868

1097

if(debug){

869

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

1098

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

1099

" searching...\n");

870

1100

}

871

1101

break;

872

1102

}

873

1103

}

874

1104

875

sig_atomic_t quit_now = 0;

876

877

static void handle_sigterm(__attribute__((unused)) int sig){

1105

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

1106

static void handle_sigterm(int sig){

878

1107

if(quit_now){

879

1108

return;

880

1109

}

881

1110

quit_now = 1;

1111

signal_received = sig;

882

1112

int old_errno = errno;

1113

/* set main loop to exit */

883

1114

if(mc.simple_poll != NULL){

884

1115

avahi_simple_poll_quit(mc.simple_poll);

885

1116

}

886

1117

errno = old_errno;

887

1118

}

888

1119

1120

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

1121

int ret;

1122

1123

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

1124

if(s < 0){

1125

perror_plus("socket");

1126

return false;

1127

}

1128

strcpy(ifr->ifr_name, ifname);

1129

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1130

if(ret == -1){

1131

if(debug){

1132

perror_plus("ioctl SIOCGIFFLAGS");

1133

}

1134

return false;

1135

}

1136

return true;

1137

}

1138

1139

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

1140

1141

/* Reject the loopback device */

1142

if(ifr->ifr_flags & IFF_LOOPBACK){

1143

if(debug){

1144

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

1145

ifname);

1146

}

1147

return false;

1148

}

1149

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

1150

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

1151

if(debug){

1152

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

1153

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

1154

}

1155

return true;

1156

}

1157

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

1158

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

1159

if(debug){

1160

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1161

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

1162

}

1163

return false;

1164

}

1165

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

1166

if(ifr->ifr_flags & IFF_NOARP){

1167

if(debug){

1168

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

1169

ifname);

1170

}

1171

return false;

1172

}

1173

1174

/* Accept this device */

1175

if(debug){

1176

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

1177

}

1178

return true;

1179

}

1180

1181

/*

1182

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

1183

* corresponds to an acceptable network device.

1184

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

1185

*/

1186

int good_interface(const struct dirent *if_entry){

1187

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

1188

return 0;

1189

}

1190

1191

struct ifreq ifr;

1192

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

1193

if(debug){

1194

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

1195

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

1196

}

1197

return 0;

1198

}

1199

1200

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

1201

return 0;

1202

}

1203

return 1;

1204

}

1205

1206

/*

1207

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

1208

* corresponds to an acceptable network device which is up.

1209

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

1210

*/

1211

int up_interface(const struct dirent *if_entry){

1212

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

1213

return 0;

1214

}

1215

1216

struct ifreq ifr;

1217

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

1218

if(debug){

1219

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

1220

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

1221

}

1222

return 0;

1223

}

1224

1225

/* Reject down interfaces */

1226

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

1227

if(debug){

1228

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

1229

if_entry->d_name);

1230

}

1231

return 0;

1232

}

1233

1234

/* Reject non-running interfaces */

1235

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

1236

if(debug){

1237

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

1238

if_entry->d_name);

1239

}

1240

return 0;

1241

}

1242

1243

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

1244

return 0;

1245

}

1246

return 1;

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

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

1394

const float delay){

1395

struct dirent **direntries;

1396

struct dirent *direntry;

1397

int ret;

1398

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

1399

alphasort);

1400

if(numhooks == -1){

1401

perror_plus("scandir");

1402

} else {

1403

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

1404

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

1405

direntry = direntries[i];

1406

char *fullname = NULL;

1407

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

1408

if(ret < 0){

1409

perror_plus("asprintf");

1410

continue;

1411

}

1412

if(debug){

1413

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

1414

direntry->d_name);

1415

}

1416

pid_t hook_pid = fork();

1417

if(hook_pid == 0){

1418

/* Child */

1419

/* Raise privileges */

1420

errno = 0;

1421

ret = seteuid(0);

1422

if(ret == -1){

1423

perror_plus("seteuid");

1424

}

1425

/* Raise privileges even more */

1426

errno = 0;

1427

ret = setuid(0);

1428

if(ret == -1){

1429

perror_plus("setuid");

1430

}

1431

/* Set group */

1432

errno = 0;

1433

ret = setgid(0);

1434

if(ret == -1){

1435

perror_plus("setgid");

1436

}

1437

/* Reset supplementary groups */

1438

errno = 0;

1439

ret = setgroups(0, NULL);

1440

if(ret == -1){

1441

perror_plus("setgroups");

1442

}

1443

dup2(devnull, STDIN_FILENO);

1444

close(devnull);

1445

dup2(STDERR_FILENO, STDOUT_FILENO);

1446

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

1447

if(ret == -1){

1448

perror_plus("setenv");

1449

_exit(EX_OSERR);

1450

}

1451

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

1452

if(ret == -1){

1453

perror_plus("setenv");

1454

_exit(EX_OSERR);

1455

}

1456

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

1457

if(ret == -1){

1458

perror_plus("setenv");

1459

_exit(EX_OSERR);

1460

}

1461

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

1462

if(ret == -1){

1463

perror_plus("setenv");

1464

_exit(EX_OSERR);

1465

}

1466

char *delaystring;

1467

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

1468

if(ret == -1){

1469

perror_plus("asprintf");

1470

_exit(EX_OSERR);

1471

}

1472

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

1473

if(ret == -1){

1474

free(delaystring);

1475

perror_plus("setenv");

1476

_exit(EX_OSERR);

1477

}

1478

free(delaystring);

1479

if(connect_to != NULL){

1480

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

1481

if(ret == -1){

1482

perror_plus("setenv");

1483

_exit(EX_OSERR);

1484

}

1485

}

1486

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

1487

perror_plus("execl");

1488

_exit(EXIT_FAILURE);

1489

}

1490

} else {

1491

int status;

1492

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

1493

perror_plus("waitpid");

1494

free(fullname);

1495

continue;

1496

}

1497

if(WIFEXITED(status)){

1498

if(WEXITSTATUS(status) != 0){

1499

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

1500

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

1501

WEXITSTATUS(status));

1502

free(fullname);

1503

continue;

1504

}

1505

} else if(WIFSIGNALED(status)){

1506

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

1507

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

1508

WTERMSIG(status));

1509

free(fullname);

1510

continue;

1511

} else {

1512

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

1513

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

1514

free(fullname);

1515

continue;

1516

}

1517

}

1518

free(fullname);

1519

if(debug){

1520

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

1521

direntry->d_name);

1522

}

1523

}

1524

close(devnull);

1525

}

1526

return true;

1527

}

1528

889

1529

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

890

1530

AvahiSServiceBrowser *sb = NULL;

891

1531

int error;

892

1532

int ret;

893

1533

intmax_t tmpmax;

894

int numchars;

1534

char *tmp;

895

1535

int exitcode = EXIT_SUCCESS;

896

const char *interface = "eth0";

1536

const char *interface = "";

897

1537

struct ifreq network;

898

int sd;

1538

int sd = -1;

1539

bool take_down_interface = false;

899

1540

uid_t uid;

900

1541

gid_t gid;

901

char *connect_to = NULL;

902

1542

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

903

1543

bool tempdir_created = false;

904

1544

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

905

1545

const char *seckey = PATHDIR "/" SECKEY;

906

1546

const char *pubkey = PATHDIR "/" PUBKEY;

907

1547

908

/* Initialize Mandos context */

909

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

910

.dh_bits = 1024, .priority = "SECURE256"

911

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

912

1548

bool gnutls_initialized = false;

913

1549

bool gpgme_initialized = false;

914

double delay = 2.5;

915

916

struct sigaction old_sigterm_action;

1550

float delay = 2.5f;

1551

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

1552

retrying the same server again */

1553

1554

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

917

1555

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

918

1556

1557

uid = getuid();

1558

gid = getgid();

1559

1560

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

1561

errno = 0;

1562

ret = setgid(gid);

1563

if(ret == -1){

1564

perror_plus("setgid");

1565

}

1566

1567

/* Lower user privileges (temporarily) */

1568

errno = 0;

1569

ret = seteuid(uid);

1570

if(ret == -1){

1571

perror_plus("seteuid");

1572

}

1573

1574

if(quit_now){

1575

goto end;

1576

}

1577

919

1578

{

920

1579

struct argp_option options[] = {

921

1580

{ .name = "debug", .key = 128,

950

1609

.arg = "SECONDS",

951

1610

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

952

1611

.group = 2 },

1612

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

1613

.arg = "SECONDS",

1614

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

1615

.group = 2 },

1616

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

1617

.arg = "DIR",

1618

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

1619

.group = 2 },

1620

/*

1621

* These reproduce what we would get without ARGP_NO_HELP

1622

*/

1623

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

1624

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

1625

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

1626

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

1627

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

1628

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

953

1629

{ .name = NULL }

954

1630

};

955

1631

956

1632

error_t parse_opt(int key, char *arg,

957

1633

struct argp_state *state){

1634

errno = 0;

958

1635

switch(key){

959

1636

case 128: /* --debug */

960

1637

debug = true;

972

1649

pubkey = arg;

973

1650

break;

974

1651

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

975

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

976

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

977

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

978

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

979

exit(EXIT_FAILURE);

1652

errno = 0;

1653

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

1654

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

1655

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

1656

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

980

1657

}

981

1658

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

982

1659

break;

984

1661

mc.priority = arg;

985

1662

break;

986

1663

case 131: /* --delay */

987

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

988

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

989

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

990

exit(EXIT_FAILURE);

991

}

992

break;

993

case ARGP_KEY_ARG:

994

argp_usage(state);

995

case ARGP_KEY_END:

1664

errno = 0;

1665

delay = strtof(arg, &tmp);

1666

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

1667

argp_error(state, "Bad delay");

1668

}

1669

case 132: /* --retry */

1670

errno = 0;

1671

retry_interval = strtod(arg, &tmp);

1672

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

1673

or (retry_interval * 1000) > INT_MAX

1674

or retry_interval < 0){

1675

argp_error(state, "Bad retry interval");

1676

}

1677

break;

1678

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

1679

hookdir = arg;

1680

break;

1681

/*

1682

* These reproduce what we would get without ARGP_NO_HELP

1683

*/

1684

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

1685

argp_state_help(state, state->out_stream,

1686

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

1687

& ~(unsigned int)ARGP_HELP_EXIT_OK);

1688

case -3: /* --usage */

1689

argp_state_help(state, state->out_stream,

1690

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1691

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

1692

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

1693

exit(argp_err_exit_status);

996

1694

break;

997

1695

default:

998

1696

return ARGP_ERR_UNKNOWN;

999

1697

}

1000

return 0;

1698

return errno;

1001

1699

}

1002

1700

1003

1701

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

1004

1702

.args_doc = "",

1005

1703

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

1006

1704

" passwords from a Mandos server" };

1007

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

1008

if(ret == ARGP_ERR_UNKNOWN){

1009

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

1705

ret = argp_parse(&argp, argc, argv,

1706

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1707

switch(ret){

1708

case 0:

1709

break;

1710

case ENOMEM:

1711

default:

1712

errno = ret;

1713

perror_plus("argp_parse");

1714

exitcode = EX_OSERR;

1715

goto end;

1716

case EINVAL:

1717

exitcode = EX_USAGE;

1718

goto end;

1719

}

1720

}

1721

1722

{

1723

/* Work around Debian bug #633582:

1724

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

1725

1726

/* Re-raise priviliges */

1727

errno = 0;

1728

ret = seteuid(0);

1729

if(ret == -1){

1730

perror_plus("seteuid");

1731

} else {

1732

struct stat st;

1733

1734

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

1735

int seckey_fd = open(seckey, O_RDONLY);

1736

if(seckey_fd == -1){

1737

perror_plus("open");

1738

} else {

1739

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

1740

if(ret == -1){

1741

perror_plus("fstat");

1742

} else {

1743

if(S_ISREG(st.st_mode)

1744

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

1745

ret = fchown(seckey_fd, uid, gid);

1746

if(ret == -1){

1747

perror_plus("fchown");

1748

}

1749

}

1750

}

1751

TEMP_FAILURE_RETRY(close(seckey_fd));

1752

}

1753

}

1754

1755

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

1756

int pubkey_fd = open(pubkey, O_RDONLY);

1757

if(pubkey_fd == -1){

1758

perror_plus("open");

1759

} else {

1760

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

1761

if(ret == -1){

1762

perror_plus("fstat");

1763

} else {

1764

if(S_ISREG(st.st_mode)

1765

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

1766

ret = fchown(pubkey_fd, uid, gid);

1767

if(ret == -1){

1768

perror_plus("fchown");

1769

}

1770

}

1771

}

1772

TEMP_FAILURE_RETRY(close(pubkey_fd));

1773

}

1774

}

1775

1776

/* Lower privileges */

1777

errno = 0;

1778

ret = seteuid(uid);

1779

if(ret == -1){

1780

perror_plus("seteuid");

1781

}

1782

}

1783

}

1784

1785

/* Run network hooks */

1786

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

1787

goto end;

1788

}

1789

1790

if(not debug){

1791

avahi_set_log_function(empty_log);

1792

}

1793

1794

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

1795

struct dirent **direntries;

1796

/* First look for interfaces that are up */

1797

ret = scandir(sys_class_net, &direntries, up_interface,

1798

alphasort);

1799

if(ret == 0){

1800

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

1801

free(direntries);

1802

ret = scandir(sys_class_net, &direntries, good_interface,

1803

alphasort);

1804

}

1805

if(ret >= 1){

1806

/* Pick the first interface returned */

1807

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

1808

if(debug){

1809

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

1810

}

1811

if(interface == NULL){

1812

perror_plus("malloc");

1813

free(direntries);

1814

exitcode = EXIT_FAILURE;

1815

goto end;

1816

}

1817

free(direntries);

1818

} else {

1819

free(direntries);

1820

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

1010

1821

exitcode = EXIT_FAILURE;

1011

1822

goto end;

1012

1823

}

1013

1824

}

1014

1825

1826

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

1827

from the signal handler */

1828

/* Initialize the pseudo-RNG for Avahi */

1829

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

1830

mc.simple_poll = avahi_simple_poll_new();

1831

if(mc.simple_poll == NULL){

1832

fprintf_plus(stderr,

1833

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

1834

exitcode = EX_UNAVAILABLE;

1835

goto end;

1836

}

1837

1838

sigemptyset(&sigterm_action.sa_mask);

1839

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

1840

if(ret == -1){

1841

perror_plus("sigaddset");

1842

exitcode = EX_OSERR;

1843

goto end;

1844

}

1845

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

1846

if(ret == -1){

1847

perror_plus("sigaddset");

1848

exitcode = EX_OSERR;

1849

goto end;

1850

}

1851

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

1852

if(ret == -1){

1853

perror_plus("sigaddset");

1854

exitcode = EX_OSERR;

1855

goto end;

1856

}

1857

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

1858

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

1859

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

1860

*/

1861

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

1862

if(ret == -1){

1863

perror_plus("sigaction");

1864

return EX_OSERR;

1865

}

1866

if(old_sigterm_action.sa_handler != SIG_IGN){

1867

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

1868

if(ret == -1){

1869

perror_plus("sigaction");

1870

exitcode = EX_OSERR;

1871

goto end;

1872

}

1873

}

1874

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

1875

if(ret == -1){

1876

perror_plus("sigaction");

1877

return EX_OSERR;

1878

}

1879

if(old_sigterm_action.sa_handler != SIG_IGN){

1880

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

1881

if(ret == -1){

1882

perror_plus("sigaction");

1883

exitcode = EX_OSERR;

1884

goto end;

1885

}

1886

}

1887

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

1888

if(ret == -1){

1889

perror_plus("sigaction");

1890

return EX_OSERR;

1891

}

1892

if(old_sigterm_action.sa_handler != SIG_IGN){

1893

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

1894

if(ret == -1){

1895

perror_plus("sigaction");

1896

exitcode = EX_OSERR;

1897

goto end;

1898

}

1899

}

1900

1015

1901

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

1016

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

1902

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

1903

if_index = (AvahiIfIndex) if_nametoindex(interface);

1904

if(if_index == 0){

1905

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

1906

exitcode = EX_UNAVAILABLE;

1907

goto end;

1908

}

1909

1910

if(quit_now){

1911

goto end;

1912

}

1913

1914

/* Re-raise priviliges */

1915

errno = 0;

1916

ret = seteuid(0);

1917

if(ret == -1){

1918

perror_plus("seteuid");

1919

}

1920

1017

1921

#ifdef __linux__

1018

1922

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1019

messages to mess up the prompt */

1923

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

1020

1924

ret = klogctl(8, NULL, 5);

1021

1925

bool restore_loglevel = true;

1022

1926

if(ret == -1){

1023

1927

restore_loglevel = false;

1024

perror("klogctl");

1928

perror_plus("klogctl");

1025

1929

}

1026

1930

#endif /* __linux__ */

1027

1931

1028

1932

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1029

1933

if(sd < 0){

1030

perror("socket");

1031

exitcode = EXIT_FAILURE;

1934

perror_plus("socket");

1935

exitcode = EX_OSERR;

1032

1936

#ifdef __linux__

1033

1937

if(restore_loglevel){

1034

1938

ret = klogctl(7, NULL, 0);

1035

1939

if(ret == -1){

1036

perror("klogctl");

1940

perror_plus("klogctl");

1037

1941

}

1038

1942

}

1039

1943

#endif /* __linux__ */

1944

/* Lower privileges */

1945

errno = 0;

1946

ret = seteuid(uid);

1947

if(ret == -1){

1948

perror_plus("seteuid");

1949

}

1040

1950

goto end;

1041

1951

}

1042

1952

strcpy(network.ifr_name, interface);

1043

1953

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

1044

1954

if(ret == -1){

1045

perror("ioctl SIOCGIFFLAGS");

1955

perror_plus("ioctl SIOCGIFFLAGS");

1046

1956

#ifdef __linux__

1047

1957

if(restore_loglevel){

1048

1958

ret = klogctl(7, NULL, 0);

1049

1959

if(ret == -1){

1050

perror("klogctl");

1960

perror_plus("klogctl");

1051

1961

}

1052

1962

}

1053

1963

#endif /* __linux__ */

1054

exitcode = EXIT_FAILURE;

1964

exitcode = EX_OSERR;

1965

/* Lower privileges */

1966

errno = 0;

1967

ret = seteuid(uid);

1968

if(ret == -1){

1969

perror_plus("seteuid");

1970

}

1055

1971

goto end;

1056

1972

}

1057

1973

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

1058

1974

network.ifr_flags |= IFF_UP;

1975

take_down_interface = true;

1059

1976

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

1060

1977

if(ret == -1){

1061

perror("ioctl SIOCSIFFLAGS");

1062

exitcode = EXIT_FAILURE;

1978

take_down_interface = false;

1979

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1980

exitcode = EX_OSERR;

1063

1981

#ifdef __linux__

1064

1982

if(restore_loglevel){

1065

1983

ret = klogctl(7, NULL, 0);

1066

1984

if(ret == -1){

1067

perror("klogctl");

1985

perror_plus("klogctl");

1068

1986

}

1069

1987

}

1070

1988

#endif /* __linux__ */

1989

/* Lower privileges */

1990

errno = 0;

1991

ret = seteuid(uid);

1992

if(ret == -1){

1993

perror_plus("seteuid");

1994

}

1071

1995

goto end;

1072

1996

}

1073

1997

}

1074

/* sleep checking until interface is running */

1998

/* Sleep checking until interface is running.

1999

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

1075

2000

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

1076

2001

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

1077

2002

if(ret == -1){

1078

perror("ioctl SIOCGIFFLAGS");

2003

perror_plus("ioctl SIOCGIFFLAGS");

1079

2004

} else if(network.ifr_flags & IFF_RUNNING){

1080

2005

break;

1081

2006

}

1082

2007

struct timespec sleeptime = { .tv_nsec = 250000000 };

1083

2008

ret = nanosleep(&sleeptime, NULL);

1084

2009

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

1085

perror("nanosleep");

2010

perror_plus("nanosleep");

1086

2011

}

1087

2012

}

1088

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

1089

if(ret == -1){

1090

perror("close");

2013

if(not take_down_interface){

2014

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

2015

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

2016

if(ret == -1){

2017

perror_plus("close");

2018

}

1091

2019

}

1092

2020

#ifdef __linux__

1093

2021

if(restore_loglevel){

1094

2022

/* Restores kernel loglevel to default */

1095

2023

ret = klogctl(7, NULL, 0);

1096

2024

if(ret == -1){

1097

perror("klogctl");

2025

perror_plus("klogctl");

1098

2026

}

1099

2027

}

1100

2028

#endif /* __linux__ */

1101

}

1102

1103

uid = getuid();

1104

gid = getgid();

1105

1106

errno = 0;

1107

setgid(gid);

1108

if(ret == -1){

1109

perror("setgid");

1110

}

1111

1112

ret = setuid(uid);

1113

if(ret == -1){

1114

perror("setuid");

2029

/* Lower privileges */

2030

errno = 0;

2031

/* Lower privileges */

2032

ret = seteuid(uid);

2033

if(ret == -1){

2034

perror_plus("seteuid");

2035

}

2036

}

2037

2038

if(quit_now){

2039

goto end;

1115

2040

}

1116

2041

1117

2042

ret = init_gnutls_global(pubkey, seckey);

1118

2043

if(ret == -1){

1119

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

1120

exitcode = EXIT_FAILURE;

2044

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

2045

exitcode = EX_UNAVAILABLE;

1121

2046

goto end;

1122

2047

} else {

1123

2048

gnutls_initialized = true;

1124

2049

}

1125

2050

2051

if(quit_now){

2052

goto end;

2053

}

2054

1126

2055

if(mkdtemp(tempdir) == NULL){

1127

perror("mkdtemp");

2056

perror_plus("mkdtemp");

1128

2057

goto end;

1129

2058

}

1130

2059

tempdir_created = true;

1131

2060

2061

if(quit_now){

2062

goto end;

2063

}

2064

1132

2065

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

1133

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

1134

exitcode = EXIT_FAILURE;

2066

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

2067

exitcode = EX_UNAVAILABLE;

1135

2068

goto end;

1136

2069

} else {

1137

2070

gpgme_initialized = true;

1138

2071

}

1139

2072

1140

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

1141

if_index = (AvahiIfIndex) if_nametoindex(interface);

1142

if(if_index == 0){

1143

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

1144

exitcode = EXIT_FAILURE;

1145

goto end;

1146

}

2073

if(quit_now){

2074

goto end;

1147

2075

}

1148

2076

1149

2077

if(connect_to != NULL){

1151

2079

/* (Mainly meant for debugging) */

1152

2080

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

1153

2081

if(address == NULL){

1154

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

1155

exitcode = EXIT_FAILURE;

1156

goto end;

1157

}

2082

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

2083

exitcode = EX_USAGE;

2084

goto end;

2085

}

2086

2087

if(quit_now){

2088

goto end;

2089

}

2090

1158

2091

uint16_t port;

1159

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

1160

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

1161

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

1162

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

1163

exitcode = EXIT_FAILURE;

1164

goto end;

1165

}

2092

errno = 0;

2093

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

2094

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

2095

or tmpmax != (uint16_t)tmpmax){

2096

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

2097

exitcode = EX_USAGE;

2098

goto end;

2099

}

2100

2101

if(quit_now){

2102

goto end;

2103

}

2104

1166

2105

port = (uint16_t)tmpmax;

1167

2106

*address = '\0';

1168

address = connect_to;

1169

2107

/* Colon in address indicates IPv6 */

1170

2108

int af;

1171

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

2109

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

1172

2110

af = AF_INET6;

2111

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

2112

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

2113

{

2114

connect_to++;

2115

address[-1] = '\0';

2116

}

1173

2117

} else {

1174

2118

af = AF_INET;

1175

2119

}

1176

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

1177

if(ret < 0){

1178

exitcode = EXIT_FAILURE;

1179

} else {

2120

address = connect_to;

2121

2122

if(quit_now){

2123

goto end;

2124

}

2125

2126

while(not quit_now){

2127

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

2128

if(quit_now or ret == 0){

2129

break;

2130

}

2131

if(debug){

2132

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

2133

(int)retry_interval);

2134

}

2135

sleep((int)retry_interval);

2136

}

2137

2138

if (not quit_now){

1180

2139

exitcode = EXIT_SUCCESS;

1181

2140

}

2141

1182

2142

goto end;

1183

2143

}

1184

2144

1185

if(not debug){

1186

avahi_set_log_function(empty_log);

1187

}

1188

1189

/* Initialize the pseudo-RNG for Avahi */

1190

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

1191

1192

/* Allocate main Avahi loop object */

1193

mc.simple_poll = avahi_simple_poll_new();

1194

if(mc.simple_poll == NULL){

1195

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

1196

exitcode = EXIT_FAILURE;

2145

if(quit_now){

1197

2146

goto end;

1198

2147

}

1199

2148

1217

2166

1218

2167

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

1219

2168

if(mc.server == NULL){

1220

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

1221

avahi_strerror(error));

1222

exitcode = EXIT_FAILURE;

2169

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

2170

avahi_strerror(error));

2171

exitcode = EX_UNAVAILABLE;

2172

goto end;

2173

}

2174

2175

if(quit_now){

1223

2176

goto end;

1224

2177

}

1225

2178

1226

2179

/* Create the Avahi service browser */

1227

2180

sb = avahi_s_service_browser_new(mc.server, if_index,

1228

AVAHI_PROTO_INET6, "_mandos._tcp",

2181

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1229

2182

NULL, 0, browse_callback, NULL);

1230

2183

if(sb == NULL){

1231

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

1232

avahi_strerror(avahi_server_errno(mc.server)));

1233

exitcode = EXIT_FAILURE;

2184

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

2185

avahi_strerror(avahi_server_errno(mc.server)));

2186

exitcode = EX_UNAVAILABLE;

1234

2187

goto end;

1235

2188

}

1236

2189

1237

sigemptyset(&sigterm_action.sa_mask);

1238

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

1239

if(ret == -1){

1240

perror("sigaddset");

1241

exitcode = EXIT_FAILURE;

1242

goto end;

1243

}

1244

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

1245

if(ret == -1){

1246

perror("sigaddset");

1247

exitcode = EXIT_FAILURE;

1248

goto end;

1249

}

1250

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

1251

if(ret == -1){

1252

perror("sigaddset");

1253

exitcode = EXIT_FAILURE;

1254

goto end;

1255

}

1256

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

1257

if(ret == -1){

1258

perror("sigaction");

1259

exitcode = EXIT_FAILURE;

1260

goto end;

1261

}

2190

if(quit_now){

2191

goto end;

2192

}

1262

2193

1263

2194

/* Run the main loop */

1264

2195

1265

2196

if(debug){

1266

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

1267

}

1268

1269

avahi_simple_poll_loop(mc.simple_poll);

2197

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

2198

}

2199

2200

ret = avahi_loop_with_timeout(mc.simple_poll,

2201

(int)(retry_interval * 1000));

2202

if(debug){

2203

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

2204

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

2205

}

1270

2206

1271

2207

end:

1272

2208

1273

2209

if(debug){

1274

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

2210

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

1275

2211

}

1276

2212

1277

2213

/* Cleanup things */

1294

2230

gpgme_release(mc.ctx);

1295

2231

}

1296

2232

1297

/* Removes the temp directory used by GPGME */

2233

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

2234

has seen */

2235

if(mc.current_server != NULL){

2236

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

2237

while(mc.current_server != NULL){

2238

server *next = mc.current_server->next;

2239

free(mc.current_server);

2240

mc.current_server = next;

2241

}

2242

}

2243

2244

/* Run network hooks */

2245

run_network_hooks("stop", interface, delay);

2246

2247

/* Re-raise priviliges */

2248

{

2249

errno = 0;

2250

ret = seteuid(0);

2251

if(ret == -1){

2252

perror_plus("seteuid");

2253

}

2254

2255

/* Take down the network interface */

2256

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

2257

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

2258

if(ret == -1){

2259

perror_plus("ioctl SIOCGIFFLAGS");

2260

} else if(network.ifr_flags & IFF_UP){

2261

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

2262

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

2263

if(ret == -1){

2264

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2265

}

2266

}

2267

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

2268

if(ret == -1){

2269

perror_plus("close");

2270

}

2271

}

2272

}

2273

/* Lower privileges permanently */

2274

errno = 0;

2275

ret = setuid(uid);

2276

if(ret == -1){

2277

perror_plus("setuid");

2278

}

2279

2280

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

1298

2281

if(tempdir_created){

1299

DIR *d;

1300

struct dirent *direntry;

1301

d = opendir(tempdir);

1302

if(d == NULL){

1303

if(errno != ENOENT){

1304

perror("opendir");

1305

}

1306

} else {

1307

while(true){

1308

direntry = readdir(d);

1309

if(direntry == NULL){

1310

break;

1311

}

1312

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

1313

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

1314

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

1315

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

1316

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

1317

continue;

1318

}

2282

struct dirent **direntries = NULL;

2283

struct dirent *direntry = NULL;

2284

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

2285

alphasort);

2286

if (numentries > 0){

2287

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

2288

direntry = direntries[i];

1319

2289

char *fullname = NULL;

1320

2290

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

1321

2291

direntry->d_name);

1322

2292

if(ret < 0){

1323

perror("asprintf");

2293

perror_plus("asprintf");

1324

2294

continue;

1325

2295

}

1326

2296

ret = remove(fullname);

1327

2297

if(ret == -1){

1328

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

1329

strerror(errno));

2298

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

2299

strerror(errno));

1330

2300

}

1331

2301

free(fullname);

1332

2302

}

1333

closedir(d);

2303

}

2304

2305

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

2306

free(direntries);

2307

if (numentries == -1){

2308

perror_plus("scandir");

1334

2309

}

1335

2310

ret = rmdir(tempdir);

1336

2311

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

1337

perror("rmdir");

1338

}

2312

perror_plus("rmdir");

2313

}

2314

}

2315

2316

if(quit_now){

2317

sigemptyset(&old_sigterm_action.sa_mask);

2318

old_sigterm_action.sa_handler = SIG_DFL;

2319

ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,

2320

&old_sigterm_action,

2321

NULL));

2322

if(ret == -1){

2323

perror_plus("sigaction");

2324

}

2325

do {

2326

ret = raise(signal_received);

2327

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

2328

if(ret != 0){

2329

perror_plus("raise");

2330

abort();

2331

}

2332

TEMP_FAILURE_RETRY(pause());

1339

2333

}

1340

2334

1341

2335

return exitcode;