/mandos/trunk : revision 594.1.4

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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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32

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

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

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stdout, ferror(), remove() */

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

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

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

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

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srand(), strtof() */

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

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argz_delete(), argz_append(),

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argz_stringify(), argz_add(),

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argz_count() */

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#ifdef __linux__

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97

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

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115

init_gnutls_session(),

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116

GNUTLS_* */

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117

#include <gnutls/openpgp.h>

108

/* 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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120

111

121

/* GPGME */

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122

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

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130

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

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131

#define SECKEY "seckey.txt"

122

132

#define PUBKEY "pubkey.txt"

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

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134

124

135

bool debug = false;

125

136

static const char mandos_protocol_version[] = "1";

126

137

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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uid_t uid = 65534;

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gid_t gid = 65534;

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145

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

146

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;

152

struct server *next;

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struct server *prev;

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} server;

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129

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

130

157

typedef struct {

135

162

gnutls_dh_params_t dh_params;

136

163

const char *priority;

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164

gpgme_ctx_t ctx;

165

server *current_server;

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166

} mandos_context;

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167

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168

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

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169

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

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170

.dh_bits = 1024, .priority = "SECURE256"

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

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

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.current_server = NULL };

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174

sig_atomic_t quit_now = 0;

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int signal_received = 0;

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177

/* Function to use when printing errors */

178

void perror_plus(const char *print_text){

179

int e = errno;

180

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

181

program_invocation_short_name);

182

errno = e;

183

perror(print_text);

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}

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186

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

187

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

188

va_list ap;

189

va_start (ap, format);

190

191

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

192

program_invocation_short_name));

193

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

194

}

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195

145

196

/*

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197

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

148

199

* "buffer_length" is how much is already used.

149

200

*/

150

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size_t incbuffer(char **buffer, size_t buffer_length,

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size_t buffer_capacity){

202

size_t buffer_capacity){

152

203

if(buffer_length + BUFFER_SIZE > buffer_capacity){

153

204

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

154

205

if(buffer == NULL){

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210

return buffer_capacity;

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211

}

161

212

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

214

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

215

int af){

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int ret;

217

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

218

if(new_server == NULL){

219

perror_plus("malloc");

220

return false;

221

}

222

*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){

227

perror_plus("strdup");

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return false;

229

}

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/* Special case of first server */

231

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 */

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} else {

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new_server->next = mc.current_server;

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

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new_server->prev->next = new_server;

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mc.current_server->prev = new_server;

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}

242

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

243

if(ret == -1){

244

perror_plus("clock_gettime");

245

return false;

246

}

247

return true;

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}

249

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250

/*

163

251

* Initialize GPGME.

164

252

*/

165

static bool init_gpgme(const char *seckey,

166

const char *pubkey, const char *tempdir){

167

int ret;

253

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

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const char *tempdir){

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gpgme_error_t rc;

169

256

gpgme_engine_info_t engine_info;

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257

173

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

174

261

*/

175

262

bool import_key(const char *filename){

263

int ret;

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264

int fd;

177

265

gpgme_data_t pgp_data;

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266

179

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

180

268

if(fd == -1){

181

perror("open");

269

perror_plus("open");

182

270

return false;

183

271

}

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272

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rc = gpgme_data_new_from_fd(&pgp_data, fd);

186

274

if(rc != GPG_ERR_NO_ERROR){

187

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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}

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

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}

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

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if(ret == -1){

201

perror("close");

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perror_plus("close");

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}

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291

gpgme_data_release(pgp_data);

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return true;

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}

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if(debug){

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

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

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}

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/* Init GPGME */

212

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gpgme_check_version(NULL);

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rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

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302

if(rc != GPG_ERR_NO_ERROR){

215

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

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gpgme_strsource(rc), gpgme_strerror(rc));

303

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

304

gpgme_strsource(rc), gpgme_strerror(rc));

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305

return false;

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306

}

219

307

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

308

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

221

309

rc = gpgme_get_engine_info(&engine_info);

222

310

if(rc != GPG_ERR_NO_ERROR){

223

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

224

gpgme_strsource(rc), gpgme_strerror(rc));

311

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

312

gpgme_strsource(rc), gpgme_strerror(rc));

225

313

return false;

226

314

}

227

315

while(engine_info != NULL){

233

321

engine_info = engine_info->next;

234

322

}

235

323

if(engine_info == NULL){

236

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

324

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

325

tempdir);

237

326

return false;

238

327

}

239

328

240

329

/* Create new GPGME "context" */

241

330

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

242

331

if(rc != GPG_ERR_NO_ERROR){

243

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

244

gpgme_strsource(rc), gpgme_strerror(rc));

332

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

333

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

334

gpgme_strerror(rc));

245

335

return false;

246

336

}

247

337

266

356

ssize_t plaintext_length = 0;

267

357

268

358

if(debug){

269

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

359

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

270

360

}

271

361

272

362

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

273

363

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

274

364

0);

275

365

if(rc != GPG_ERR_NO_ERROR){

276

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

277

gpgme_strsource(rc), gpgme_strerror(rc));

366

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

367

gpgme_strsource(rc), gpgme_strerror(rc));

278

368

return -1;

279

369

}

280

370

281

371

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

282

372

rc = gpgme_data_new(&dh_plain);

283

373

if(rc != GPG_ERR_NO_ERROR){

284

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

285

gpgme_strsource(rc), gpgme_strerror(rc));

374

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

375

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

376

gpgme_strsource(rc), gpgme_strerror(rc));

286

377

gpgme_data_release(dh_crypto);

287

378

return -1;

288

379

}

291

382

data buffer */

292

383

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

293

384

if(rc != GPG_ERR_NO_ERROR){

294

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

295

gpgme_strsource(rc), gpgme_strerror(rc));

385

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

386

gpgme_strsource(rc), gpgme_strerror(rc));

296

387

plaintext_length = -1;

297

388

if(debug){

298

389

gpgme_decrypt_result_t result;

299

390

result = gpgme_op_decrypt_result(mc.ctx);

300

391

if(result == NULL){

301

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

392

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

302

393

} else {

303

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

304

result->unsupported_algorithm);

305

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

306

result->wrong_key_usage);

394

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

395

result->unsupported_algorithm);

396

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

397

result->wrong_key_usage);

307

398

if(result->file_name != NULL){

308

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

399

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

309

400

}

310

401

gpgme_recipient_t recipient;

311

402

recipient = result->recipients;

312

403

while(recipient != NULL){

313

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

314

gpgme_pubkey_algo_name(recipient->pubkey_algo));

315

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

316

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

317

recipient->status == GPG_ERR_NO_SECKEY

318

? "No" : "Yes");

404

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

405

gpgme_pubkey_algo_name

406

(recipient->pubkey_algo));

407

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

408

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

409

recipient->status == GPG_ERR_NO_SECKEY

410

? "No" : "Yes");

319

411

recipient = recipient->next;

320

412

}

321

413

}

324

416

}

325

417

326

418

if(debug){

327

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

419

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

328

420

}

329

421

330

422

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

331

423

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

332

perror("gpgme_data_seek");

424

perror_plus("gpgme_data_seek");

333

425

plaintext_length = -1;

334

426

goto decrypt_end;

335

427

}

337

429

*plaintext = NULL;

338

430

while(true){

339

431

plaintext_capacity = incbuffer(plaintext,

340

(size_t)plaintext_length,

341

plaintext_capacity);

432

(size_t)plaintext_length,

433

plaintext_capacity);

342

434

if(plaintext_capacity == 0){

343

perror("incbuffer");

344

plaintext_length = -1;

345

goto decrypt_end;

435

perror_plus("incbuffer");

436

plaintext_length = -1;

437

goto decrypt_end;

346

438

}

347

439

348

440

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

353

445

break;

354

446

}

355

447

if(ret < 0){

356

perror("gpgme_data_read");

448

perror_plus("gpgme_data_read");

357

449

plaintext_length = -1;

358

450

goto decrypt_end;

359

451

}

361

453

}

362

454

363

455

if(debug){

364

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

456

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

365

457

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

366

458

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

367

459

}

389

481

/* GnuTLS log function callback */

390

482

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

391

483

const char* string){

392

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

484

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

393

485

}

394

486

395

487

static int init_gnutls_global(const char *pubkeyfilename,

397

489

int ret;

398

490

399

491

if(debug){

400

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

492

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

401

493

}

402

494

403

495

ret = gnutls_global_init();

404

496

if(ret != GNUTLS_E_SUCCESS){

405

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

406

safer_gnutls_strerror(ret));

497

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

498

safer_gnutls_strerror(ret));

407

499

return -1;

408

500

}

409

501

416

508

}

417

509

418

510

/* OpenPGP credentials */

419

gnutls_certificate_allocate_credentials(&mc.cred);

511

ret = gnutls_certificate_allocate_credentials(&mc.cred);

420

512

if(ret != GNUTLS_E_SUCCESS){

421

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

422

from

423

-Wunreachable-code

424

*/

425

safer_gnutls_strerror(ret));

513

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

514

safer_gnutls_strerror(ret));

426

515

gnutls_global_deinit();

427

516

return -1;

428

517

}

429

518

430

519

if(debug){

431

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

432

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

433

seckeyfilename);

520

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

521

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

522

pubkeyfilename,

523

seckeyfilename);

434

524

}

435

525

436

526

ret = gnutls_certificate_set_openpgp_key_file

437

527

(mc.cred, pubkeyfilename, seckeyfilename,

438

528

GNUTLS_OPENPGP_FMT_BASE64);

439

529

if(ret != GNUTLS_E_SUCCESS){

440

fprintf(stderr,

441

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

442

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

443

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

444

safer_gnutls_strerror(ret));

530

fprintf_plus(stderr,

531

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

532

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

533

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

534

safer_gnutls_strerror(ret));

445

535

goto globalfail;

446

536

}

447

537

448

538

/* GnuTLS server initialization */

449

539

ret = gnutls_dh_params_init(&mc.dh_params);

450

540

if(ret != GNUTLS_E_SUCCESS){

451

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

452

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

541

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

542

" initialization: %s\n",

543

safer_gnutls_strerror(ret));

453

544

goto globalfail;

454

545

}

455

546

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

456

547

if(ret != GNUTLS_E_SUCCESS){

457

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

458

safer_gnutls_strerror(ret));

548

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

549

safer_gnutls_strerror(ret));

459

550

goto globalfail;

460

551

}

461

552

474

565

static int init_gnutls_session(gnutls_session_t *session){

475

566

int ret;

476

567

/* GnuTLS session creation */

477

ret = gnutls_init(session, GNUTLS_SERVER);

568

do {

569

ret = gnutls_init(session, GNUTLS_SERVER);

570

if(quit_now){

571

return -1;

572

}

573

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

478

574

if(ret != GNUTLS_E_SUCCESS){

479

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

480

safer_gnutls_strerror(ret));

575

fprintf_plus(stderr,

576

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

577

safer_gnutls_strerror(ret));

481

578

}

482

579

483

580

{

484

581

const char *err;

485

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

582

do {

583

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

584

if(quit_now){

585

gnutls_deinit(*session);

586

return -1;

587

}

588

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

486

589

if(ret != GNUTLS_E_SUCCESS){

487

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

488

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

489

safer_gnutls_strerror(ret));

590

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

591

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

592

safer_gnutls_strerror(ret));

490

593

gnutls_deinit(*session);

491

594

return -1;

492

595

}

493

596

}

494

597

495

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

496

mc.cred);

598

do {

599

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

600

mc.cred);

601

if(quit_now){

602

gnutls_deinit(*session);

603

return -1;

604

}

605

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

497

606

if(ret != GNUTLS_E_SUCCESS){

498

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

499

safer_gnutls_strerror(ret));

607

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

608

safer_gnutls_strerror(ret));

500

609

gnutls_deinit(*session);

501

610

return -1;

502

611

}

503

612

504

613

/* ignore client certificate if any. */

505

gnutls_certificate_server_set_request(*session,

506

GNUTLS_CERT_IGNORE);

614

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

507

615

508

616

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

509

617

514

622

static void empty_log(__attribute__((unused)) AvahiLogLevel level,

515

623

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

516

624

517

sig_atomic_t quit_now = 0;

518

int signal_received = 0;

519

520

625

/* Called when a Mandos server is found */

521

626

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

522

627

AvahiIfIndex if_index,

528

633

struct sockaddr_in6 in6;

529

634

} to;

530

635

char *buffer = NULL;

531

char *decrypted_buffer;

636

char *decrypted_buffer = NULL;

532

637

size_t buffer_length = 0;

533

638

size_t buffer_capacity = 0;

534

ssize_t decrypted_buffer_size;

535

639

size_t written;

536

int retval = 0;

640

int retval = -1;

537

641

gnutls_session_t session;

538

642

int pf; /* Protocol family */

539

643

644

errno = 0;

645

540

646

if(quit_now){

647

errno = EINTR;

541

648

return -1;

542

649

}

543

650

549

656

pf = PF_INET;

550

657

break;

551

658

default:

552

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

659

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

660

errno = EINVAL;

553

661

return -1;

554

662

}

555

663

559

667

}

560

668

561

669

if(debug){

562

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

563

"\n", ip, port);

670

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

671

PRIu16 "\n", ip, port);

564

672

}

565

673

566

674

tcp_sd = socket(pf, SOCK_STREAM, 0);

567

675

if(tcp_sd < 0){

568

perror("socket");

569

retval = -1;

676

int e = errno;

677

perror_plus("socket");

678

errno = e;

570

679

goto mandos_end;

571

680

}

572

681

573

682

if(quit_now){

683

errno = EINTR;

574

684

goto mandos_end;

575

685

}

576

686

583

693

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

584

694

}

585

695

if(ret < 0 ){

586

perror("inet_pton");

587

retval = -1;

696

int e = errno;

697

perror_plus("inet_pton");

698

errno = e;

588

699

goto mandos_end;

589

700

}

590

701

if(ret == 0){

591

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

592

retval = -1;

702

int e = errno;

703

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

704

errno = e;

593

705

goto mandos_end;

594

706

}

595

707

if(af == AF_INET6){

599

711

600

712

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

601

713

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

602

-Wunreachable-code*/

714

-Wunreachable-code*/

603

715

if(if_index == AVAHI_IF_UNSPEC){

604

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

605

" without a network interface\n");

606

retval = -1;

716

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

717

" incomplete without a network interface\n");

718

errno = EINVAL;

607

719

goto mandos_end;

608

720

}

609

721

/* Set the network interface number as scope */

616

728

}

617

729

618

730

if(quit_now){

731

errno = EINTR;

619

732

goto mandos_end;

620

733

}

621

734

623

736

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

624

737

char interface[IF_NAMESIZE];

625

738

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

626

perror("if_indextoname");

739

perror_plus("if_indextoname");

627

740

} else {

628

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

629

ip, interface, port);

741

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

742

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

630

743

}

631

744

} else {

632

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

633

port);

745

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

746

ip, port);

634

747

}

635

748

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

636

749

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

643

756

sizeof(addrstr));

644

757

}

645

758

if(pcret == NULL){

646

perror("inet_ntop");

759

perror_plus("inet_ntop");

647

760

} else {

648

761

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

649

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

762

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

650

763

}

651

764

}

652

765

}

653

766

654

767

if(quit_now){

768

errno = EINTR;

655

769

goto mandos_end;

656

770

}

657

771

661

775

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

662

776

}

663

777

if(ret < 0){

664

perror("connect");

665

retval = -1;

778

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

779

int e = errno;

780

perror_plus("connect");

781

errno = e;

782

}

666

783

goto mandos_end;

667

784

}

668

785

669

786

if(quit_now){

787

errno = EINTR;

670

788

goto mandos_end;

671

789

}

672

790

675

793

while(true){

676

794

size_t out_size = strlen(out);

677

795

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

678

out_size - written));

796

out_size - written));

679

797

if(ret == -1){

680

perror("write");

681

retval = -1;

798

int e = errno;

799

perror_plus("write");

800

errno = e;

682

801

goto mandos_end;

683

802

}

684

803

written += (size_t)ret;

694

813

}

695

814

696

815

if(quit_now){

816

errno = EINTR;

697

817

goto mandos_end;

698

818

}

699

819

}

700

820

701

821

if(debug){

702

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

703

}

704

705

if(quit_now){

706

goto mandos_end;

707

}

708

709

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

710

711

if(quit_now){

712

goto mandos_end;

713

}

714

715

do{

822

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

823

}

824

825

if(quit_now){

826

errno = EINTR;

827

goto mandos_end;

828

}

829

830

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

831

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

832

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

833

gnutls_transport_set_ptr(session,

834

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

835

836

if(quit_now){

837

errno = EINTR;

838

goto mandos_end;

839

}

840

841

do {

716

842

ret = gnutls_handshake(session);

717

843

if(quit_now){

844

errno = EINTR;

718

845

goto mandos_end;

719

846

}

720

847

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

721

848

722

849

if(ret != GNUTLS_E_SUCCESS){

723

850

if(debug){

724

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

851

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

725

852

gnutls_perror(ret);

726

853

}

727

retval = -1;

854

errno = EPROTO;

728

855

goto mandos_end;

729

856

}

730

857

731

858

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

732

859

733

860

if(debug){

734

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

735

ip);

861

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

862

" %s\n", ip);

736

863

}

737

864

738

865

while(true){

739

866

740

867

if(quit_now){

868

errno = EINTR;

741

869

goto mandos_end;

742

870

}

743

871

744

872

buffer_capacity = incbuffer(&buffer, buffer_length,

745

buffer_capacity);

873

buffer_capacity);

746

874

if(buffer_capacity == 0){

747

perror("incbuffer");

748

retval = -1;

875

int e = errno;

876

perror_plus("incbuffer");

877

errno = e;

749

878

goto mandos_end;

750

879

}

751

880

752

881

if(quit_now){

882

errno = EINTR;

753

883

goto mandos_end;

754

884

}

755

885

764

894

case GNUTLS_E_AGAIN:

765

895

break;

766

896

case GNUTLS_E_REHANDSHAKE:

767

do{

897

do {

768

898

ret = gnutls_handshake(session);

769

899

770

900

if(quit_now){

901

errno = EINTR;

771

902

goto mandos_end;

772

903

}

773

904

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

774

905

if(ret < 0){

775

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

906

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

907

"***\n");

776

908

gnutls_perror(ret);

777

retval = -1;

909

errno = EPROTO;

778

910

goto mandos_end;

779

911

}

780

912

break;

781

913

default:

782

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

783

" encrypted session with Mandos server\n");

784

retval = -1;

914

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

915

" encrypted session with Mandos server\n");

785

916

gnutls_bye(session, GNUTLS_SHUT_RDWR);

917

errno = EIO;

786

918

goto mandos_end;

787

919

}

788

920

} else {

791

923

}

792

924

793

925

if(debug){

794

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

795

}

796

797

if(quit_now){

798

goto mandos_end;

799

}

800

801

gnutls_bye(session, GNUTLS_SHUT_RDWR);

802

803

if(quit_now){

804

goto mandos_end;

805

}

926

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

927

}

928

929

if(quit_now){

930

errno = EINTR;

931

goto mandos_end;

932

}

933

934

do {

935

ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);

936

if(quit_now){

937

errno = EINTR;

938

goto mandos_end;

939

}

940

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

806

941

807

942

if(buffer_length > 0){

808

decrypted_buffer_size = pgp_packet_decrypt(buffer,

809

buffer_length,

943

ssize_t decrypted_buffer_size;

944

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

810

945

&decrypted_buffer);

811

946

if(decrypted_buffer_size >= 0){

947

812

948

written = 0;

813

949

while(written < (size_t) decrypted_buffer_size){

814

950

if(quit_now){

951

errno = EINTR;

815

952

goto mandos_end;

816

953

}

817

954

819

956

(size_t)decrypted_buffer_size - written,

820

957

stdout);

821

958

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

959

int e = errno;

822

960

if(debug){

823

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

824

strerror(errno));

961

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

962

strerror(errno));

825

963

}

826

retval = -1;

827

break;

964

errno = e;

965

goto mandos_end;

828

966

}

829

967

written += (size_t)ret;

830

968

}

831

free(decrypted_buffer);

832

} else {

833

retval = -1;

969

retval = 0;

834

970

}

835

} else {

836

retval = -1;

837

971

}

838

972

839

973

/* Shutdown procedure */

840

974

841

975

mandos_end:

842

free(buffer);

843

if(tcp_sd >= 0){

844

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

845

}

846

if(ret == -1){

847

perror("close");

848

}

849

gnutls_deinit(session);

850

if(quit_now){

851

retval = -1;

976

{

977

int e = errno;

978

free(decrypted_buffer);

979

free(buffer);

980

if(tcp_sd >= 0){

981

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

982

}

983

if(ret == -1){

984

if(e == 0){

985

e = errno;

986

}

987

perror_plus("close");

988

}

989

gnutls_deinit(session);

990

errno = e;

991

if(quit_now){

992

errno = EINTR;

993

retval = -1;

994

}

852

995

}

853

996

return retval;

854

997

}

879

1022

switch(event){

880

1023

default:

881

1024

case AVAHI_RESOLVER_FAILURE:

882

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

883

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

884

avahi_strerror(avahi_server_errno(mc.server)));

1025

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

1026

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

1027

domain,

1028

avahi_strerror(avahi_server_errno(mc.server)));

885

1029

break;

886

1030

887

1031

case AVAHI_RESOLVER_FOUND:

889

1033

char ip[AVAHI_ADDRESS_STR_MAX];

890

1034

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

891

1035

if(debug){

892

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

893

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

894

ip, (intmax_t)interface, port);

1036

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

1037

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

1038

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

895

1039

}

896

1040

int ret = start_mandos_communication(ip, port, interface,

897

1041

avahi_proto_to_af(proto));

898

1042

if(ret == 0){

899

1043

avahi_simple_poll_quit(mc.simple_poll);

1044

} else {

1045

if(not add_server(ip, port, interface,

1046

avahi_proto_to_af(proto))){

1047

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

1048

" list\n", name);

1049

}

900

1050

}

901

1051

}

902

1052

}

926

1076

default:

927

1077

case AVAHI_BROWSER_FAILURE:

928

1078

929

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

930

avahi_strerror(avahi_server_errno(mc.server)));

1079

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

1080

avahi_strerror(avahi_server_errno(mc.server)));

931

1081

avahi_simple_poll_quit(mc.simple_poll);

932

1082

return;

933

1083

940

1090

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

941

1091

name, type, domain, protocol, 0,

942

1092

resolve_callback, NULL) == NULL)

943

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

944

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

1093

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

1094

" %s\n", name,

1095

avahi_strerror(avahi_server_errno(mc.server)));

945

1096

break;

946

1097

947

1098

case AVAHI_BROWSER_REMOVE:

950

1101

case AVAHI_BROWSER_ALL_FOR_NOW:

951

1102

case AVAHI_BROWSER_CACHE_EXHAUSTED:

952

1103

if(debug){

953

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

1104

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

1105

" searching...\n");

954

1106

}

955

1107

break;

956

1108

}

957

1109

}

958

1110

959

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

1111

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

960

1112

static void handle_sigterm(int sig){

961

1113

if(quit_now){

962

1114

return;

964

1116

quit_now = 1;

965

1117

signal_received = sig;

966

1118

int old_errno = errno;

1119

/* set main loop to exit */

967

1120

if(mc.simple_poll != NULL){

968

1121

avahi_simple_poll_quit(mc.simple_poll);

969

1122

}

970

1123

errno = old_errno;

971

1124

}

972

1125

1126

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

1127

int ret;

1128

error_t ret_errno;

1129

1130

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

1131

if(s < 0){

1132

ret_errno = errno;

1133

perror_plus("socket");

1134

errno = ret_errno;

1135

return false;

1136

}

1137

strcpy(ifr->ifr_name, ifname);

1138

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1139

if(ret == -1){

1140

if(debug){

1141

ret_errno = errno;

1142

perror_plus("ioctl SIOCGIFFLAGS");

1143

errno = ret_errno;

1144

}

1145

return false;

1146

}

1147

return true;

1148

}

1149

1150

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

1151

1152

/* Reject the loopback device */

1153

if(ifr->ifr_flags & IFF_LOOPBACK){

1154

if(debug){

1155

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

1156

ifname);

1157

}

1158

return false;

1159

}

1160

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

1161

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

1162

if(debug){

1163

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

1164

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

1165

}

1166

return true;

1167

}

1168

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

1169

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

1170

if(debug){

1171

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1172

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

1173

}

1174

return false;

1175

}

1176

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

1177

if(ifr->ifr_flags & IFF_NOARP){

1178

if(debug){

1179

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

1180

ifname);

1181

}

1182

return false;

1183

}

1184

1185

/* Accept this device */

1186

if(debug){

1187

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

1188

}

1189

return true;

1190

}

1191

1192

/*

1193

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

1194

* corresponds to an acceptable network device.

1195

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

1196

*/

1197

int good_interface(const struct dirent *if_entry){

1198

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

1199

return 0;

1200

}

1201

1202

struct ifreq ifr;

1203

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

1204

if(debug){

1205

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

1206

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

1207

}

1208

return 0;

1209

}

1210

1211

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

1212

return 0;

1213

}

1214

return 1;

1215

}

1216

1217

/*

1218

* This function determines if a network interface is up.

1219

*/

1220

bool interface_is_up(const char *interface){

1221

struct ifreq ifr;

1222

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

1223

if(debug){

1224

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

1225

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

1226

}

1227

return false;

1228

}

1229

1230

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

1231

}

1232

1233

/*

1234

* This function determines if a network interface is running

1235

*/

1236

bool interface_is_running(const char *interface){

1237

struct ifreq ifr;

1238

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

1239

if(debug){

1240

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

1241

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

1242

}

1243

return false;

1244

}

1245

1246

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

1247

}

1248

1249

int notdotentries(const struct dirent *direntry){

1250

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

1251

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

1252

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

1253

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

1254

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

1255

return 0;

1256

}

1257

return 1;

1258

}

1259

1260

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

1261

int runnable_hook(const struct dirent *direntry){

1262

int ret;

1263

size_t sret;

1264

struct stat st;

1265

1266

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

1267

/* Empty name? */

1268

return 0;

1269

}

1270

1271

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

1272

"abcdefghijklmnopqrstuvwxyz"

1273

"0123456789"

1274

"_-");

1275

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

1276

/* Contains non-allowed characters */

1277

if(debug){

1278

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

1279

direntry->d_name);

1280

}

1281

return 0;

1282

}

1283

1284

char *fullname = NULL;

1285

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

1286

if(ret < 0){

1287

perror_plus("asprintf");

1288

return 0;

1289

}

1290

1291

ret = stat(fullname, &st);

1292

if(ret == -1){

1293

if(debug){

1294

perror_plus("Could not stat hook");

1295

}

1296

return 0;

1297

}

1298

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

1299

/* Not a regular file */

1300

if(debug){

1301

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

1302

direntry->d_name);

1303

}

1304

return 0;

1305

}

1306

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

1307

/* Not executable */

1308

if(debug){

1309

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

1310

direntry->d_name);

1311

}

1312

return 0;

1313

}

1314

if(debug){

1315

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

1316

direntry->d_name);

1317

}

1318

return 1;

1319

}

1320

1321

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1322

int ret;

1323

struct timespec now;

1324

struct timespec waited_time;

1325

intmax_t block_time;

1326

1327

while(true){

1328

if(mc.current_server == NULL){

1329

if (debug){

1330

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

1331

" No timeout!\n");

1332

}

1333

ret = avahi_simple_poll_iterate(s, -1);

1334

} else {

1335

if (debug){

1336

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

1337

" it, or wait\n");

1338

}

1339

/* the current time */

1340

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1341

if(ret == -1){

1342

perror_plus("clock_gettime");

1343

return -1;

1344

}

1345

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

1346

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

1347

waited_time.tv_sec = (now.tv_sec

1348

- mc.current_server->last_seen.tv_sec);

1349

waited_time.tv_nsec = (now.tv_nsec

1350

- mc.current_server->last_seen.tv_nsec);

1351

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

1352

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

1353

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

1354

block_time = ((retry_interval

1355

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

1356

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

1357

1358

if (debug){

1359

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

1360

block_time);

1361

}

1362

1363

if(block_time <= 0){

1364

ret = start_mandos_communication(mc.current_server->ip,

1365

mc.current_server->port,

1366

mc.current_server->if_index,

1367

mc.current_server->af);

1368

if(ret == 0){

1369

avahi_simple_poll_quit(mc.simple_poll);

1370

return 0;

1371

}

1372

ret = clock_gettime(CLOCK_MONOTONIC,

1373

&mc.current_server->last_seen);

1374

if(ret == -1){

1375

perror_plus("clock_gettime");

1376

return -1;

1377

}

1378

mc.current_server = mc.current_server->next;

1379

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

1380

servers, but don't block */

1381

}

1382

1383

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

1384

}

1385

if(ret != 0){

1386

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

1387

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

1388

}

1389

}

1390

}

1391

}

1392

1393

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

1394

error_t raise_privileges(void){

1395

error_t old_errno = errno;

1396

error_t ret_errno = 0;

1397

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

1398

ret_errno = errno;

1399

perror_plus("seteuid");

1400

}

1401

errno = old_errno;

1402

return ret_errno;

1403

}

1404

1405

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

1406

error_t raise_privileges_permanently(void){

1407

error_t old_errno = errno;

1408

error_t ret_errno = raise_privileges();

1409

if(ret_errno != 0){

1410

errno = old_errno;

1411

return ret_errno;

1412

}

1413

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

1414

ret_errno = errno;

1415

perror_plus("seteuid");

1416

}

1417

errno = old_errno;

1418

return ret_errno;

1419

}

1420

1421

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

1422

error_t lower_privileges(void){

1423

error_t old_errno = errno;

1424

error_t ret_errno = 0;

1425

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

1426

ret_errno = errno;

1427

perror_plus("seteuid");

1428

}

1429

errno = old_errno;

1430

return ret_errno;

1431

}

1432

1433

/* Lower privileges permanently */

1434

error_t lower_privileges_permanently(void){

1435

error_t old_errno = errno;

1436

error_t ret_errno = 0;

1437

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

1438

ret_errno = errno;

1439

perror_plus("setuid");

1440

}

1441

errno = old_errno;

1442

return ret_errno;

1443

}

1444

1445

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

1446

const float delay){

1447

struct dirent **direntries;

1448

struct dirent *direntry;

1449

int ret;

1450

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

1451

alphasort);

1452

if(numhooks == -1){

1453

perror_plus("scandir");

1454

} else {

1455

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

1456

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

1457

direntry = direntries[i];

1458

char *fullname = NULL;

1459

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

1460

if(ret < 0){

1461

perror_plus("asprintf");

1462

continue;

1463

}

1464

if(debug){

1465

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

1466

direntry->d_name);

1467

}

1468

pid_t hook_pid = fork();

1469

if(hook_pid == 0){

1470

/* Child */

1471

/* Raise privileges */

1472

raise_privileges_permanently();

1473

/* Set group */

1474

errno = 0;

1475

ret = setgid(0);

1476

if(ret == -1){

1477

perror_plus("setgid");

1478

}

1479

/* Reset supplementary groups */

1480

errno = 0;

1481

ret = setgroups(0, NULL);

1482

if(ret == -1){

1483

perror_plus("setgroups");

1484

}

1485

dup2(devnull, STDIN_FILENO);

1486

close(devnull);

1487

dup2(STDERR_FILENO, STDOUT_FILENO);

1488

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

1489

if(ret == -1){

1490

perror_plus("setenv");

1491

_exit(EX_OSERR);

1492

}

1493

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

1494

if(ret == -1){

1495

perror_plus("setenv");

1496

_exit(EX_OSERR);

1497

}

1498

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

1499

if(ret == -1){

1500

perror_plus("setenv");

1501

_exit(EX_OSERR);

1502

}

1503

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

1504

if(ret == -1){

1505

perror_plus("setenv");

1506

_exit(EX_OSERR);

1507

}

1508

char *delaystring;

1509

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

1510

if(ret == -1){

1511

perror_plus("asprintf");

1512

_exit(EX_OSERR);

1513

}

1514

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

1515

if(ret == -1){

1516

free(delaystring);

1517

perror_plus("setenv");

1518

_exit(EX_OSERR);

1519

}

1520

free(delaystring);

1521

if(connect_to != NULL){

1522

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

1523

if(ret == -1){

1524

perror_plus("setenv");

1525

_exit(EX_OSERR);

1526

}

1527

}

1528

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

1529

perror_plus("execl");

1530

_exit(EXIT_FAILURE);

1531

}

1532

} else {

1533

int status;

1534

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

1535

perror_plus("waitpid");

1536

free(fullname);

1537

continue;

1538

}

1539

if(WIFEXITED(status)){

1540

if(WEXITSTATUS(status) != 0){

1541

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

1542

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

1543

WEXITSTATUS(status));

1544

free(fullname);

1545

continue;

1546

}

1547

} else if(WIFSIGNALED(status)){

1548

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

1549

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

1550

WTERMSIG(status));

1551

free(fullname);

1552

continue;

1553

} else {

1554

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

1555

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

1556

free(fullname);

1557

continue;

1558

}

1559

}

1560

free(fullname);

1561

if(debug){

1562

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

1563

direntry->d_name);

1564

}

1565

}

1566

close(devnull);

1567

}

1568

return true;

1569

}

1570

1571

error_t bring_up_interface(const char *const interface,

1572

const float delay){

1573

int sd = -1;

1574

error_t old_errno = errno;

1575

error_t ret_errno = 0;

1576

int ret, ret_setflags;

1577

struct ifreq network;

1578

unsigned int if_index = if_nametoindex(interface);

1579

if(if_index == 0){

1580

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

1581

errno = old_errno;

1582

return ENXIO;

1583

}

1584

1585

if(quit_now){

1586

errno = old_errno;

1587

return EINTR;

1588

}

1589

1590

if(not interface_is_up(interface)){

1591

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

1592

ret_errno = errno;

1593

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

1594

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

1595

return ret_errno;

1596

}

1597

network.ifr_flags |= IFF_UP;

1598

1599

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1600

if(sd < 0){

1601

ret_errno = errno;

1602

perror_plus("socket");

1603

errno = old_errno;

1604

return ret_errno;

1605

}

1606

1607

if(quit_now){

1608

close(sd);

1609

errno = old_errno;

1610

return EINTR;

1611

}

1612

1613

if(debug){

1614

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

1615

interface);

1616

}

1617

1618

/* Raise priviliges */

1619

raise_privileges();

1620

1621

#ifdef __linux__

1622

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1623

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

1624

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

1625

bool restore_loglevel = true;

1626

if(ret_linux == -1){

1627

restore_loglevel = false;

1628

perror_plus("klogctl");

1629

}

1630

#endif /* __linux__ */

1631

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

1632

ret_errno = errno;

1633

#ifdef __linux__

1634

if(restore_loglevel){

1635

ret_linux = klogctl(7, NULL, 0);

1636

if(ret_linux == -1){

1637

perror_plus("klogctl");

1638

}

1639

}

1640

#endif /* __linux__ */

1641

1642

/* Lower privileges */

1643

lower_privileges();

1644

1645

/* Close the socket */

1646

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

1647

if(ret == -1){

1648

perror_plus("close");

1649

}

1650

1651

if(ret_setflags == -1){

1652

errno = ret_errno;

1653

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1654

errno = old_errno;

1655

return ret_errno;

1656

}

1657

} else if(debug){

1658

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

1659

interface);

1660

}

1661

1662

/* Sleep checking until interface is running.

1663

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

1664

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

1665

if(interface_is_running(interface)){

1666

break;

1667

}

1668

struct timespec sleeptime = { .tv_nsec = 250000000 };

1669

ret = nanosleep(&sleeptime, NULL);

1670

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

1671

perror_plus("nanosleep");

1672

}

1673

}

1674

1675

errno = old_errno;

1676

return 0;

1677

}

1678

1679

error_t take_down_interface(const char *const interface){

1680

int sd = -1;

1681

error_t old_errno = errno;

1682

error_t ret_errno = 0;

1683

int ret, ret_setflags;

1684

struct ifreq network;

1685

unsigned int if_index = if_nametoindex(interface);

1686

if(if_index == 0){

1687

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

1688

errno = old_errno;

1689

return ENXIO;

1690

}

1691

if(interface_is_up(interface)){

1692

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

1693

ret_errno = errno;

1694

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

1695

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

1696

return ret_errno;

1697

}

1698

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

1699

1700

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1701

if(sd < 0){

1702

ret_errno = errno;

1703

perror_plus("socket");

1704

errno = old_errno;

1705

return ret_errno;

1706

}

1707

1708

if(debug){

1709

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

1710

interface);

1711

}

1712

1713

/* Raise priviliges */

1714

raise_privileges();

1715

1716

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

1717

ret_errno = errno;

1718

1719

/* Lower privileges */

1720

lower_privileges();

1721

1722

/* Close the socket */

1723

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

1724

if(ret == -1){

1725

perror_plus("close");

1726

}

1727

1728

if(ret_setflags == -1){

1729

errno = ret_errno;

1730

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1731

errno = old_errno;

1732

return ret_errno;

1733

}

1734

} else if(debug){

1735

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

1736

interface);

1737

}

1738

1739

errno = old_errno;

1740

return 0;

1741

}

1742

973

1743

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

974

1744

AvahiSServiceBrowser *sb = NULL;

975

int error;

1745

error_t ret_errno;

976

1746

int ret;

977

1747

intmax_t tmpmax;

978

1748

char *tmp;

979

1749

int exitcode = EXIT_SUCCESS;

980

const char *interface = "eth0";

981

struct ifreq network;

982

int sd = -1;

983

bool take_down_interface = false;

984

uid_t uid;

985

gid_t gid;

986

char *connect_to = NULL;

1750

char *interfaces = NULL;

1751

size_t interfaces_size = 0;

1752

char *interfaces_to_take_down = NULL;

1753

size_t interfaces_to_take_down_size = 0;

987

1754

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

988

1755

bool tempdir_created = false;

989

1756

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

990

1757

const char *seckey = PATHDIR "/" SECKEY;

991

1758

const char *pubkey = PATHDIR "/" PUBKEY;

1759

char *interfaces_hooks = NULL;

1760

size_t interfaces_hooks_size = 0;

992

1761

993

1762

bool gnutls_initialized = false;

994

1763

bool gpgme_initialized = false;

995

1764

float delay = 2.5f;

1765

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

1766

retrying the same server again */

996

1767

997

struct sigaction old_sigterm_action;

1768

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

998

1769

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

999

1770

1771

uid = getuid();

1772

gid = getgid();

1773

1774

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

1775

errno = 0;

1776

ret = setgid(gid);

1777

if(ret == -1){

1778

perror_plus("setgid");

1779

}

1780

1781

/* Lower user privileges (temporarily) */

1782

errno = 0;

1783

ret = seteuid(uid);

1784

if(ret == -1){

1785

perror_plus("seteuid");

1786

}

1787

1788

if(quit_now){

1789

goto end;

1790

}

1791

1000

1792

{

1001

1793

struct argp_option options[] = {

1002

1794

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

1031

1823

.arg = "SECONDS",

1032

1824

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

1033

1825

.group = 2 },

1826

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

1827

.arg = "SECONDS",

1828

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

1829

.group = 2 },

1830

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

1831

.arg = "DIR",

1832

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

1833

.group = 2 },

1834

/*

1835

* These reproduce what we would get without ARGP_NO_HELP

1836

*/

1837

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

1838

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

1839

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

1840

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

1841

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

1842

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

1034

1843

{ .name = NULL }

1035

1844

};

1036

1845

1037

1846

error_t parse_opt(int key, char *arg,

1038

1847

struct argp_state *state){

1848

errno = 0;

1039

1849

switch(key){

1040

1850

case 128: /* --debug */

1041

1851

debug = true;

1044

1854

connect_to = arg;

1045

1855

break;

1046

1856

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

1047

interface = arg;

1857

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

1858

(int)',');

1859

if(ret_errno != 0){

1860

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

1861

}

1048

1862

break;

1049

1863

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

1050

1864

seckey = arg;

1057

1871

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

1058

1872

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

1059

1873

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

1060

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

1061

exit(EXIT_FAILURE);

1874

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

1062

1875

}

1063

1876

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

1064

1877

break;

1069

1882

errno = 0;

1070

1883

delay = strtof(arg, &tmp);

1071

1884

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

1072

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

1073

exit(EXIT_FAILURE);

1074

}

1075

break;

1076

case ARGP_KEY_ARG:

1077

argp_usage(state);

1078

case ARGP_KEY_END:

1885

argp_error(state, "Bad delay");

1886

}

1887

case 132: /* --retry */

1888

errno = 0;

1889

retry_interval = strtod(arg, &tmp);

1890

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

1891

or (retry_interval * 1000) > INT_MAX

1892

or retry_interval < 0){

1893

argp_error(state, "Bad retry interval");

1894

}

1895

break;

1896

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

1897

hookdir = arg;

1898

break;

1899

/*

1900

* These reproduce what we would get without ARGP_NO_HELP

1901

*/

1902

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

1903

argp_state_help(state, state->out_stream,

1904

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

1905

& ~(unsigned int)ARGP_HELP_EXIT_OK);

1906

case -3: /* --usage */

1907

argp_state_help(state, state->out_stream,

1908

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1909

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

1910

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

1911

exit(argp_err_exit_status);

1079

1912

break;

1080

1913

default:

1081

1914

return ARGP_ERR_UNKNOWN;

1082

1915

}

1083

return 0;

1916

return errno;

1084

1917

}

1085

1918

1086

1919

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

1087

1920

.args_doc = "",

1088

1921

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

1089

1922

" passwords from a Mandos server" };

1090

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

1091

if(ret == ARGP_ERR_UNKNOWN){

1092

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

1093

exitcode = EXIT_FAILURE;

1923

ret = argp_parse(&argp, argc, argv,

1924

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1925

switch(ret){

1926

case 0:

1927

break;

1928

case ENOMEM:

1929

default:

1930

errno = ret;

1931

perror_plus("argp_parse");

1932

exitcode = EX_OSERR;

1933

goto end;

1934

case EINVAL:

1935

exitcode = EX_USAGE;

1936

goto end;

1937

}

1938

}

1939

1940

{

1941

/* Work around Debian bug #633582:

1942

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

1943

1944

/* Re-raise priviliges */

1945

if(raise_privileges() == 0){

1946

struct stat st;

1947

1948

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

1949

int seckey_fd = open(seckey, O_RDONLY);

1950

if(seckey_fd == -1){

1951

perror_plus("open");

1952

} else {

1953

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

1954

if(ret == -1){

1955

perror_plus("fstat");

1956

} else {

1957

if(S_ISREG(st.st_mode)

1958

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

1959

ret = fchown(seckey_fd, uid, gid);

1960

if(ret == -1){

1961

perror_plus("fchown");

1962

}

1963

}

1964

}

1965

TEMP_FAILURE_RETRY(close(seckey_fd));

1966

}

1967

}

1968

1969

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

1970

int pubkey_fd = open(pubkey, O_RDONLY);

1971

if(pubkey_fd == -1){

1972

perror_plus("open");

1973

} else {

1974

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

1975

if(ret == -1){

1976

perror_plus("fstat");

1977

} else {

1978

if(S_ISREG(st.st_mode)

1979

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

1980

ret = fchown(pubkey_fd, uid, gid);

1981

if(ret == -1){

1982

perror_plus("fchown");

1983

}

1984

}

1985

}

1986

TEMP_FAILURE_RETRY(close(pubkey_fd));

1987

}

1988

}

1989

1990

/* Lower privileges */

1991

errno = 0;

1992

ret = seteuid(uid);

1993

if(ret == -1){

1994

perror_plus("seteuid");

1995

}

1996

}

1997

}

1998

1999

/* Remove empty interface names */

2000

{

2001

char *interface = NULL;

2002

while((interface = argz_next(interfaces, interfaces_size,

2003

interface))){

2004

if(if_nametoindex(interface) == 0){

2005

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

2006

fprintf_plus(stderr, "Not using nonexisting interface"

2007

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

2008

}

2009

argz_delete(&interfaces, &interfaces_size, interface);

2010

interface = NULL;

2011

}

2012

}

2013

}

2014

2015

/* Run network hooks */

2016

{

2017

ret_errno = argz_append(&interfaces_hooks, &interfaces_hooks_size,

2018

interfaces, interfaces_size);

2019

if(ret_errno != 0){

2020

errno = ret_errno;

2021

perror_plus("argz_append");

2022

goto end;

2023

}

2024

argz_stringify(interfaces_hooks, interfaces_hooks_size, (int)',');

2025

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

1094

2026

goto end;

1095

2027

}

1096

2028

}

1105

2037

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

1106

2038

mc.simple_poll = avahi_simple_poll_new();

1107

2039

if(mc.simple_poll == NULL){

1108

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

1109

exitcode = EXIT_FAILURE;

2040

fprintf_plus(stderr,

2041

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

2042

exitcode = EX_UNAVAILABLE;

1110

2043

goto end;

1111

2044

}

1112

2045

1113

2046

sigemptyset(&sigterm_action.sa_mask);

1114

2047

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

1115

2048

if(ret == -1){

1116

perror("sigaddset");

1117

exitcode = EXIT_FAILURE;

2049

perror_plus("sigaddset");

2050

exitcode = EX_OSERR;

1118

2051

goto end;

1119

2052

}

1120

2053

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

1121

2054

if(ret == -1){

1122

perror("sigaddset");

1123

exitcode = EXIT_FAILURE;

2055

perror_plus("sigaddset");

2056

exitcode = EX_OSERR;

1124

2057

goto end;

1125

2058

}

1126

2059

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

1127

2060

if(ret == -1){

1128

perror("sigaddset");

1129

exitcode = EXIT_FAILURE;

2061

perror_plus("sigaddset");

2062

exitcode = EX_OSERR;

1130

2063

goto end;

1131

2064

}

1132

2065

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

1135

2068

*/

1136

2069

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

1137

2070

if(ret == -1){

1138

perror("sigaction");

1139

return EXIT_FAILURE;

2071

perror_plus("sigaction");

2072

return EX_OSERR;

1140

2073

}

1141

2074

if(old_sigterm_action.sa_handler != SIG_IGN){

1142

2075

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

1143

2076

if(ret == -1){

1144

perror("sigaction");

1145

exitcode = EXIT_FAILURE;

2077

perror_plus("sigaction");

2078

exitcode = EX_OSERR;

1146

2079

goto end;

1147

2080

}

1148

2081

}

1149

2082

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

1150

2083

if(ret == -1){

1151

perror("sigaction");

1152

return EXIT_FAILURE;

2084

perror_plus("sigaction");

2085

return EX_OSERR;

1153

2086

}

1154

2087

if(old_sigterm_action.sa_handler != SIG_IGN){

1155

2088

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

1156

2089

if(ret == -1){

1157

perror("sigaction");

1158

exitcode = EXIT_FAILURE;

2090

perror_plus("sigaction");

2091

exitcode = EX_OSERR;

1159

2092

goto end;

1160

2093

}

1161

2094

}

1162

2095

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

1163

2096

if(ret == -1){

1164

perror("sigaction");

1165

return EXIT_FAILURE;

2097

perror_plus("sigaction");

2098

return EX_OSERR;

1166

2099

}

1167

2100

if(old_sigterm_action.sa_handler != SIG_IGN){

1168

2101

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

1169

2102

if(ret == -1){

1170

perror("sigaction");

1171

exitcode = EXIT_FAILURE;

1172

goto end;

1173

}

1174

}

1175

1176

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

1177

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

1178

if_index = (AvahiIfIndex) if_nametoindex(interface);

1179

if(if_index == 0){

1180

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

1181

exitcode = EXIT_FAILURE;

1182

goto end;

1183

}

1184

1185

if(quit_now){

1186

goto end;

1187

}

1188

1189

#ifdef __linux__

1190

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1191

messages to mess up the prompt */

1192

ret = klogctl(8, NULL, 5);

1193

bool restore_loglevel = true;

1194

if(ret == -1){

1195

restore_loglevel = false;

1196

perror("klogctl");

1197

}

1198

#endif /* __linux__ */

1199

1200

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1201

if(sd < 0){

1202

perror("socket");

1203

exitcode = EXIT_FAILURE;

1204

#ifdef __linux__

1205

if(restore_loglevel){

1206

ret = klogctl(7, NULL, 0);

1207

if(ret == -1){

1208

perror("klogctl");

1209

}

1210

}

1211

#endif /* __linux__ */

1212

goto end;

1213

}

1214

strcpy(network.ifr_name, interface);

1215

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

1216

if(ret == -1){

1217

perror("ioctl SIOCGIFFLAGS");

1218

#ifdef __linux__

1219

if(restore_loglevel){

1220

ret = klogctl(7, NULL, 0);

1221

if(ret == -1){

1222

perror("klogctl");

1223

}

1224

}

1225

#endif /* __linux__ */

1226

exitcode = EXIT_FAILURE;

1227

goto end;

1228

}

1229

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

1230

network.ifr_flags |= IFF_UP;

1231

take_down_interface = true;

1232

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

1233

if(ret == -1){

1234

take_down_interface = false;

1235

perror("ioctl SIOCSIFFLAGS");

1236

exitcode = EXIT_FAILURE;

1237

#ifdef __linux__

1238

if(restore_loglevel){

1239

ret = klogctl(7, NULL, 0);

1240

if(ret == -1){

1241

perror("klogctl");

1242

}

1243

}

1244

#endif /* __linux__ */

1245

goto end;

1246

}

1247

}

1248

/* sleep checking until interface is running */

1249

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

1250

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

1251

if(ret == -1){

1252

perror("ioctl SIOCGIFFLAGS");

1253

} else if(network.ifr_flags & IFF_RUNNING){

1254

break;

1255

}

1256

struct timespec sleeptime = { .tv_nsec = 250000000 };

1257

ret = nanosleep(&sleeptime, NULL);

1258

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

1259

perror("nanosleep");

1260

}

1261

}

1262

if(not take_down_interface){

1263

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

1264

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

1265

if(ret == -1){

1266

perror("close");

1267

}

1268

}

1269

#ifdef __linux__

1270

if(restore_loglevel){

1271

/* Restores kernel loglevel to default */

1272

ret = klogctl(7, NULL, 0);

1273

if(ret == -1){

1274

perror("klogctl");

1275

}

1276

}

1277

#endif /* __linux__ */

1278

}

1279

1280

if(quit_now){

1281

goto end;

1282

}

1283

1284

uid = getuid();

1285

gid = getgid();

1286

1287

errno = 0;

1288

setgid(gid);

1289

if(ret == -1){

1290

perror("setgid");

1291

}

1292

1293

ret = setuid(uid);

1294

if(ret == -1){

1295

perror("setuid");

2103

perror_plus("sigaction");

2104

exitcode = EX_OSERR;

2105

goto end;

2106

}

2107

}

2108

2109

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

2110

if(interfaces == NULL){

2111

struct dirent **direntries;

2112

/* Look for any good interfaces */

2113

ret = scandir(sys_class_net, &direntries, good_interface,

2114

alphasort);

2115

if(ret >= 1){

2116

/* Add all found interfaces to interfaces list */

2117

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

2118

ret_errno = argz_add(&interfaces, &interfaces_size,

2119

direntries[i]->d_name);

2120

if(ret_errno != 0){

2121

perror_plus("argz_add");

2122

continue;

2123

}

2124

if(debug){

2125

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

2126

direntries[i]->d_name);

2127

}

2128

}

2129

free(direntries);

2130

} else {

2131

free(direntries);

2132

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

2133

exitcode = EXIT_FAILURE;

2134

goto end;

2135

}

2136

}

2137

2138

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

2139

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

2140

if(debug){

2141

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

2142

interfaces);

2143

}

2144

if_index = (AvahiIfIndex)if_nametoindex(interfaces);

2145

}

2146

2147

/* Bring up interfaces which are down */

2148

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

2149

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

2150

char *interface = NULL;

2151

while((interface = argz_next(interfaces, interfaces_size,

2152

interface))){

2153

bool interface_was_up = interface_is_up(interface);

2154

ret = bring_up_interface(interface, delay);

2155

if(not interface_was_up){

2156

if(ret != 0){

2157

errno = ret;

2158

perror_plus("Failed to bring up interface");

2159

} else {

2160

ret_errno = argz_add(&interfaces_to_take_down,

2161

&interfaces_to_take_down_size,

2162

interface);

2163

}

2164

}

2165

}

2166

free(interfaces);

2167

interfaces = NULL;

2168

interfaces_size = 0;

2169

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

2170

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

2171

}

1296

2172

}

1297

2173

1298

2174

if(quit_now){

1301

2177

1302

2178

ret = init_gnutls_global(pubkey, seckey);

1303

2179

if(ret == -1){

1304

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

1305

exitcode = EXIT_FAILURE;

2180

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

2181

exitcode = EX_UNAVAILABLE;

1306

2182

goto end;

1307

2183

} else {

1308

2184

gnutls_initialized = true;

1312

2188

goto end;

1313

2189

}

1314

2190

2191

if(mkdtemp(tempdir) == NULL){

2192

perror_plus("mkdtemp");

2193

goto end;

2194

}

1315

2195

tempdir_created = true;

1316

if(mkdtemp(tempdir) == NULL){

1317

tempdir_created = false;

1318

perror("mkdtemp");

1319

goto end;

1320

}

1321

2196

1322

2197

if(quit_now){

1323

2198

goto end;

1324

2199

}

1325

2200

1326

2201

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

1327

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

1328

exitcode = EXIT_FAILURE;

2202

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

2203

exitcode = EX_UNAVAILABLE;

1329

2204

goto end;

1330

2205

} else {

1331

2206

gpgme_initialized = true;

1339

2214

/* Connect directly, do not use Zeroconf */

1340

2215

/* (Mainly meant for debugging) */

1341

2216

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

2217

1342

2218

if(address == NULL){

1343

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

1344

exitcode = EXIT_FAILURE;

2219

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

2220

exitcode = EX_USAGE;

1345

2221

goto end;

1346

2222

}

1347

2223

1354

2230

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

1355

2231

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

1356

2232

or tmpmax != (uint16_t)tmpmax){

1357

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

1358

exitcode = EXIT_FAILURE;

2233

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

2234

exitcode = EX_USAGE;

1359

2235

goto end;

1360

2236

}

1361

2237

1365

2241

1366

2242

port = (uint16_t)tmpmax;

1367

2243

*address = '\0';

1368

address = connect_to;

1369

2244

/* Colon in address indicates IPv6 */

1370

2245

int af;

1371

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

2246

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

1372

2247

af = AF_INET6;

2248

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

2249

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

2250

{

2251

connect_to++;

2252

address[-1] = '\0';

2253

}

1373

2254

} else {

1374

2255

af = AF_INET;

1375

2256

}

2257

address = connect_to;

1376

2258

1377

2259

if(quit_now){

1378

2260

goto end;

1379

2261

}

1380

2262

1381

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

1382

if(ret < 0){

1383

exitcode = EXIT_FAILURE;

1384

} else {

2263

while(not quit_now){

2264

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

2265

if(quit_now or ret == 0){

2266

break;

2267

}

2268

if(debug){

2269

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

2270

(int)retry_interval);

2271

}

2272

sleep((int)retry_interval);

2273

}

2274

2275

if (not quit_now){

1385

2276

exitcode = EXIT_SUCCESS;

1386

2277

}

2278

1387

2279

goto end;

1388

2280

}

1389

2281

1403

2295

/* Allocate a new server */

1404

2296

mc.server = avahi_server_new(avahi_simple_poll_get

1405

2297

(mc.simple_poll), &config, NULL,

1406

NULL, &error);

2298

NULL, &ret_errno);

1407

2299

1408

2300

/* Free the Avahi configuration data */

1409

2301

avahi_server_config_free(&config);

1411

2303

1412

2304

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

1413

2305

if(mc.server == NULL){

1414

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

1415

avahi_strerror(error));

1416

exitcode = EXIT_FAILURE;

2306

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

2307

avahi_strerror(ret_errno));

2308

exitcode = EX_UNAVAILABLE;

1417

2309

goto end;

1418

2310

}

1419

2311

1426

2318

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1427

2319

NULL, 0, browse_callback, NULL);

1428

2320

if(sb == NULL){

1429

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

1430

avahi_strerror(avahi_server_errno(mc.server)));

1431

exitcode = EXIT_FAILURE;

2321

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

2322

avahi_strerror(avahi_server_errno(mc.server)));

2323

exitcode = EX_UNAVAILABLE;

1432

2324

goto end;

1433

2325

}

1434

2326

1439

2331

/* Run the main loop */

1440

2332

1441

2333

if(debug){

1442

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

1443

}

1444

1445

avahi_simple_poll_loop(mc.simple_poll);

2334

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

2335

}

2336

2337

ret = avahi_loop_with_timeout(mc.simple_poll,

2338

(int)(retry_interval * 1000));

2339

if(debug){

2340

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

2341

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

2342

}

1446

2343

1447

2344

end:

1448

2345

1449

2346

if(debug){

1450

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

2347

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

1451

2348

}

1452

2349

1453

2350

/* Cleanup things */

1470

2367

gpgme_release(mc.ctx);

1471

2368

}

1472

2369

1473

/* Take down the network interface */

1474

if(take_down_interface){

1475

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

1476

if(ret == -1){

1477

perror("ioctl SIOCGIFFLAGS");

1478

} else if(network.ifr_flags & IFF_UP) {

1479

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

1480

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

1481

if(ret == -1){

1482

perror("ioctl SIOCSIFFLAGS");

1483

}

1484

}

1485

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

1486

if(ret == -1){

1487

perror("close");

1488

}

1489

}

1490

1491

/* Removes the temp directory used by GPGME */

2370

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

2371

has seen */

2372

if(mc.current_server != NULL){

2373

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

2374

while(mc.current_server != NULL){

2375

server *next = mc.current_server->next;

2376

free(mc.current_server);

2377

mc.current_server = next;

2378

}

2379

}

2380

2381

/* Re-raise priviliges */

2382

{

2383

raise_privileges();

2384

2385

/* Run network hooks */

2386

run_network_hooks("stop", interfaces_hooks, delay);

2387

2388

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

2389

{

2390

char *interface = NULL;

2391

while((interface=argz_next(interfaces_to_take_down,

2392

interfaces_to_take_down_size,

2393

interface))){

2394

ret_errno = take_down_interface(interface);

2395

if(ret_errno != 0){

2396

errno = ret_errno;

2397

perror_plus("Failed to take down interface");

2398

}

2399

}

2400

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

2401

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

2402

" down\n");

2403

}

2404

}

2405

2406

lower_privileges_permanently();

2407

}

2408

2409

free(interfaces_to_take_down);

2410

free(interfaces_hooks);

2411

2412

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

1492

2413

if(tempdir_created){

1493

DIR *d;

1494

struct dirent *direntry;

1495

d = opendir(tempdir);

1496

if(d == NULL){

1497

if(errno != ENOENT){

1498

perror("opendir");

1499

}

1500

} else {

1501

while(true){

1502

direntry = readdir(d);

1503

if(direntry == NULL){

1504

break;

1505

}

1506

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

1507

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

1508

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

1509

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

1510

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

1511

continue;

1512

}

2414

struct dirent **direntries = NULL;

2415

struct dirent *direntry = NULL;

2416

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

2417

alphasort);

2418

if (numentries > 0){

2419

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

2420

direntry = direntries[i];

1513

2421

char *fullname = NULL;

1514

2422

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

1515

2423

direntry->d_name);

1516

2424

if(ret < 0){

1517

perror("asprintf");

2425

perror_plus("asprintf");

1518

2426

continue;

1519

2427

}

1520

2428

ret = remove(fullname);

1521

2429

if(ret == -1){

1522

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

1523

strerror(errno));

2430

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

2431

strerror(errno));

1524

2432

}

1525

2433

free(fullname);

1526

2434

}

1527

closedir(d);

2435

}

2436

2437

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

2438

free(direntries);

2439

if (numentries == -1){

2440

perror_plus("scandir");

1528

2441

}

1529

2442

ret = rmdir(tempdir);

1530

2443

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

1531

perror("rmdir");

2444

perror_plus("rmdir");

1532

2445

}

1533

2446

}

1534

2447

1535

2448

if(quit_now){

1536

2449

sigemptyset(&old_sigterm_action.sa_mask);

1537

2450

old_sigterm_action.sa_handler = SIG_DFL;

1538

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

2451

ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,

2452

&old_sigterm_action,

2453

NULL));

1539

2454

if(ret == -1){

1540

perror("sigaction");

1541

}

1542

raise(signal_received);

2455

perror_plus("sigaction");

2456

}

2457

do {

2458

ret = raise(signal_received);

2459

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

2460

if(ret != 0){

2461

perror_plus("raise");

2462

abort();

2463

}

2464

TEMP_FAILURE_RETRY(pause());

1543

2465

}

1544

2466

1545

2467

return exitcode;