/mandos/release : revision 237.7.200

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

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*

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* Everything else is

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*

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

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

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* along with this program. If not, see

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

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*

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

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

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*/

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

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

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stdout, ferror(), remove() */

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

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

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

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

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strtof(), abort() */

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sockaddr_in6, PF_INET6,

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SOCK_STREAM, uid_t, gid_t, open(),

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opendir(), DIR */

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

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

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

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inet_pton(), connect() */

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

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*/

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

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strtoimax() */

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

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

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

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program_invocation_short_name */

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

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

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SIOCSIFFLAGS, if_indextoname(),

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*/

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

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

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setgid(), pause() */

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

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

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

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

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

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argp_state, struct argp,

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raise() */

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

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EX_NOHOST, EX_IOERR, EX_PROTOCOL */

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

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WEXITSTATUS(), WTERMSIG() */

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

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

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argz_delete(), argz_append(),

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argz_stringify(), argz_add(),

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argz_count() */

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#ifdef __linux__

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96

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

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114

init_gnutls_session(),

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115

GNUTLS_* */

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116

#include <gnutls/openpgp.h>

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/* gnutls_certificate_set_openpgp_key_file(),

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GNUTLS_OPENPGP_FMT_BASE64 */

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/* gnutls_certificate_set_openpgp_key_file(),

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GNUTLS_OPENPGP_FMT_BASE64 */

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/* GPGME */

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121

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

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129

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

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130

#define SECKEY "seckey.txt"

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131

#define PUBKEY "pubkey.txt"

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

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133

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bool debug = false;

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135

static const char mandos_protocol_version[] = "1";

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136

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

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

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

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138

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

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139

char *connect_to = NULL;

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const char *hookdir = HOOKDIR;

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uid_t uid = 65534;

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gid_t gid = 65534;

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/* Doubly linked list that need to be circular linked when ever used */

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

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145

typedef struct server{

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146

const char *ip;

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uint16_t port;

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in_port_t port;

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148

AvahiIfIndex if_index;

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149

int af;

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150

struct timespec last_seen;

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154

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

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156

typedef struct {

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AvahiSimplePoll *simple_poll;

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157

AvahiServer *server;

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158

gnutls_certificate_credentials_t cred;

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159

unsigned int dh_bits;

151

161

const char *priority;

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162

gpgme_ctx_t ctx;

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163

server *current_server;

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char *interfaces;

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size_t interfaces_size;

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166

} mandos_context;

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167

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

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

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.dh_bits = 1024, .priority = "SECURE256"

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":!CTYPE-X.509:+CTYPE-OPENPGP", .current_server = NULL };

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/* global so signal handler can reach it*/

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AvahiSimplePoll *simple_poll;

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170

161

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sig_atomic_t quit_now = 0;

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172

int signal_received = 0;

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/* Function to use when printing errors */

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175

void perror_plus(const char *print_text){

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fprintf(stderr, "Mandos plugin %s: ", program_invocation_short_name);

176

int e = errno;

177

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

178

program_invocation_short_name);

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errno = e;

167

180

perror(print_text);

168

181

}

169

182

183

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

184

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

185

va_list ap;

186

va_start (ap, format);

187

188

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

189

program_invocation_short_name));

190

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

191

}

192

170

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/*

171

194

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

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195

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

173

196

* "buffer_length" is how much is already used.

174

197

*/

175

198

size_t incbuffer(char **buffer, size_t buffer_length,

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size_t buffer_capacity){

199

size_t buffer_capacity){

177

200

if(buffer_length + BUFFER_SIZE > buffer_capacity){

178

201

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

179

202

if(buffer == NULL){

184

207

return buffer_capacity;

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208

}

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209

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int add_server(const char *ip, uint16_t port,

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AvahiIfIndex if_index,

189

int af){

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

211

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

212

int af, server **current_server){

190

213

int ret;

191

214

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

192

215

if(new_server == NULL){

193

216

perror_plus("malloc");

194

return -1;

217

return false;

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218

}

196

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

197

.port = port,

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.if_index = if_index,

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.af = af };

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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 -1;

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return false;

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226

}

204

/* uniqe case of first server */

205

if (mc.current_server == NULL){

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/* Special case of first server */

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if(*current_server == NULL){

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229

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

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*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->next = *current_server;

235

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

213

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new_server->prev->next = new_server;

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mc.current_server->prev = new_server;

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(*current_server)->prev = new_server;

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238

}

216

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

239

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

217

240

if(ret == -1){

218

241

perror_plus("clock_gettime");

219

return -1;

242

return false;

220

243

}

221

return 0;

244

return true;

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245

}

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247

/*

225

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* Initialize GPGME.

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249

*/

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static bool init_gpgme(const char *seckey,

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const char *pubkey, const char *tempdir){

250

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

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const char *tempdir, mandos_context *mc){

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gpgme_error_t rc;

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gpgme_engine_info_t engine_info;

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233

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/*

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

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257

*/

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rc = gpgme_data_new_from_fd(&pgp_data, fd);

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if(rc != GPG_ERR_NO_ERROR){

249

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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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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}

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if(debug){

270

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

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

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293

}

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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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298

if(rc != GPG_ERR_NO_ERROR){

277

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

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gpgme_strsource(rc), gpgme_strerror(rc));

299

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

300

gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

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302

}

281

303

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

304

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

283

305

rc = gpgme_get_engine_info(&engine_info);

284

306

if(rc != GPG_ERR_NO_ERROR){

285

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

286

gpgme_strsource(rc), gpgme_strerror(rc));

307

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

308

gpgme_strsource(rc), gpgme_strerror(rc));

287

309

return false;

288

310

}

289

311

while(engine_info != NULL){

295

317

engine_info = engine_info->next;

296

318

}

297

319

if(engine_info == NULL){

298

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

320

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

321

tempdir);

299

322

return false;

300

323

}

301

324

302

325

/* Create new GPGME "context" */

303

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

326

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

304

327

if(rc != GPG_ERR_NO_ERROR){

305

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

306

gpgme_strsource(rc), gpgme_strerror(rc));

328

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

329

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

330

gpgme_strerror(rc));

307

331

return false;

308

332

}

309

333

320

344

*/

321

345

static ssize_t pgp_packet_decrypt(const char *cryptotext,

322

346

size_t crypto_size,

323

char **plaintext){

347

char **plaintext,

348

mandos_context *mc){

324

349

gpgme_data_t dh_crypto, dh_plain;

325

350

gpgme_error_t rc;

326

351

ssize_t ret;

328

353

ssize_t plaintext_length = 0;

329

354

330

355

if(debug){

331

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

356

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

332

357

}

333

358

334

359

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

335

360

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

336

361

0);

337

362

if(rc != GPG_ERR_NO_ERROR){

338

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

339

gpgme_strsource(rc), gpgme_strerror(rc));

363

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

364

gpgme_strsource(rc), gpgme_strerror(rc));

340

365

return -1;

341

366

}

342

367

343

368

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

344

369

rc = gpgme_data_new(&dh_plain);

345

370

if(rc != GPG_ERR_NO_ERROR){

346

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

347

gpgme_strsource(rc), gpgme_strerror(rc));

371

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

372

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

373

gpgme_strsource(rc), gpgme_strerror(rc));

348

374

gpgme_data_release(dh_crypto);

349

375

return -1;

350

376

}

351

377

352

378

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

353

379

data buffer */

354

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

380

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

355

381

if(rc != GPG_ERR_NO_ERROR){

356

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

357

gpgme_strsource(rc), gpgme_strerror(rc));

382

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

383

gpgme_strsource(rc), gpgme_strerror(rc));

358

384

plaintext_length = -1;

359

385

if(debug){

360

386

gpgme_decrypt_result_t result;

361

result = gpgme_op_decrypt_result(mc.ctx);

387

result = gpgme_op_decrypt_result(mc->ctx);

362

388

if(result == NULL){

363

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

389

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

364

390

} else {

365

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

366

result->unsupported_algorithm);

367

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

368

result->wrong_key_usage);

391

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

392

result->unsupported_algorithm);

393

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

394

result->wrong_key_usage);

369

395

if(result->file_name != NULL){

370

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

396

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

371

397

}

372

398

gpgme_recipient_t recipient;

373

399

recipient = result->recipients;

374

400

while(recipient != NULL){

375

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

376

gpgme_pubkey_algo_name(recipient->pubkey_algo));

377

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

378

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

379

recipient->status == GPG_ERR_NO_SECKEY

380

? "No" : "Yes");

401

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

402

gpgme_pubkey_algo_name

403

(recipient->pubkey_algo));

404

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

405

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

406

recipient->status == GPG_ERR_NO_SECKEY

407

? "No" : "Yes");

381

408

recipient = recipient->next;

382

409

}

383

410

}

386

413

}

387

414

388

415

if(debug){

389

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

416

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

390

417

}

391

418

392

419

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

399

426

*plaintext = NULL;

400

427

while(true){

401

428

plaintext_capacity = incbuffer(plaintext,

402

(size_t)plaintext_length,

403

plaintext_capacity);

429

(size_t)plaintext_length,

430

plaintext_capacity);

404

431

if(plaintext_capacity == 0){

405

perror_plus("incbuffer");

406

plaintext_length = -1;

407

goto decrypt_end;

432

perror_plus("incbuffer");

433

plaintext_length = -1;

434

goto decrypt_end;

408

435

}

409

436

410

437

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

423

450

}

424

451

425

452

if(debug){

426

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

453

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

427

454

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

428

455

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

429

456

}

441

468

}

442

469

443

470

static const char * safer_gnutls_strerror(int value){

444

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

445

-Wunreachable-code */

471

const char *ret = gnutls_strerror(value);

446

472

if(ret == NULL)

447

473

ret = "(unknown)";

448

474

return ret;

451

477

/* GnuTLS log function callback */

452

478

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

453

479

const char* string){

454

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

480

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

455

481

}

456

482

457

483

static int init_gnutls_global(const char *pubkeyfilename,

458

const char *seckeyfilename){

484

const char *seckeyfilename,

485

mandos_context *mc){

459

486

int ret;

460

487

461

488

if(debug){

462

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

489

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

463

490

}

464

491

465

492

ret = gnutls_global_init();

466

493

if(ret != GNUTLS_E_SUCCESS){

467

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

468

safer_gnutls_strerror(ret));

494

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

495

safer_gnutls_strerror(ret));

469

496

return -1;

470

497

}

471

498

478

505

}

479

506

480

507

/* OpenPGP credentials */

481

gnutls_certificate_allocate_credentials(&mc.cred);

508

ret = gnutls_certificate_allocate_credentials(&mc->cred);

482

509

if(ret != GNUTLS_E_SUCCESS){

483

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

484

from

485

-Wunreachable-code

486

*/

487

safer_gnutls_strerror(ret));

510

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

511

safer_gnutls_strerror(ret));

488

512

gnutls_global_deinit();

489

513

return -1;

490

514

}

491

515

492

516

if(debug){

493

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

494

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

495

seckeyfilename);

517

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

518

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

519

pubkeyfilename,

520

seckeyfilename);

496

521

}

497

522

498

523

ret = gnutls_certificate_set_openpgp_key_file

499

(mc.cred, pubkeyfilename, seckeyfilename,

524

(mc->cred, pubkeyfilename, seckeyfilename,

500

525

GNUTLS_OPENPGP_FMT_BASE64);

501

526

if(ret != GNUTLS_E_SUCCESS){

502

fprintf(stderr,

503

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

504

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

505

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

506

safer_gnutls_strerror(ret));

527

fprintf_plus(stderr,

528

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

529

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

530

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

531

safer_gnutls_strerror(ret));

507

532

goto globalfail;

508

533

}

509

534

510

535

/* GnuTLS server initialization */

511

ret = gnutls_dh_params_init(&mc.dh_params);

536

ret = gnutls_dh_params_init(&mc->dh_params);

512

537

if(ret != GNUTLS_E_SUCCESS){

513

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

514

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

538

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

539

" initialization: %s\n",

540

safer_gnutls_strerror(ret));

515

541

goto globalfail;

516

542

}

517

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

543

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

518

544

if(ret != GNUTLS_E_SUCCESS){

519

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

520

safer_gnutls_strerror(ret));

545

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

546

safer_gnutls_strerror(ret));

521

547

goto globalfail;

522

548

}

523

549

524

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

550

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

525

551

526

552

return 0;

527

553

528

554

globalfail:

529

555

530

gnutls_certificate_free_credentials(mc.cred);

556

gnutls_certificate_free_credentials(mc->cred);

531

557

gnutls_global_deinit();

532

gnutls_dh_params_deinit(mc.dh_params);

558

gnutls_dh_params_deinit(mc->dh_params);

533

559

return -1;

534

560

}

535

561

536

static int init_gnutls_session(gnutls_session_t *session){

562

static int init_gnutls_session(gnutls_session_t *session,

563

mandos_context *mc){

537

564

int ret;

538

565

/* GnuTLS session creation */

539

566

do {

543

570

}

544

571

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

545

572

if(ret != GNUTLS_E_SUCCESS){

546

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

547

safer_gnutls_strerror(ret));

573

fprintf_plus(stderr,

574

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

575

safer_gnutls_strerror(ret));

548

576

}

549

577

550

578

{

551

579

const char *err;

552

580

do {

553

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

581

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

554

582

if(quit_now){

555

583

gnutls_deinit(*session);

556

584

return -1;

557

585

}

558

586

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

559

587

if(ret != GNUTLS_E_SUCCESS){

560

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

561

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

562

safer_gnutls_strerror(ret));

588

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

589

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

590

safer_gnutls_strerror(ret));

563

591

gnutls_deinit(*session);

564

592

return -1;

565

593

}

567

595

568

596

do {

569

597

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

570

mc.cred);

598

mc->cred);

571

599

if(quit_now){

572

600

gnutls_deinit(*session);

573

601

return -1;

574

602

}

575

603

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

576

604

if(ret != GNUTLS_E_SUCCESS){

577

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

578

safer_gnutls_strerror(ret));

605

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

606

safer_gnutls_strerror(ret));

579

607

gnutls_deinit(*session);

580

608

return -1;

581

609

}

583

611

/* ignore client certificate if any. */

584

612

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

585

613

586

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

614

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

587

615

588

616

return 0;

589

617

}

593

621

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

594

622

595

623

/* Called when a Mandos server is found */

596

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

624

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

597

625

AvahiIfIndex if_index,

598

int af){

626

int af, mandos_context *mc){

599

627

int ret, tcp_sd = -1;

600

628

ssize_t sret;

601

629

union {

626

654

pf = PF_INET;

627

655

break;

628

656

default:

629

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

657

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

630

658

errno = EINVAL;

631

659

return -1;

632

660

}

633

661

634

ret = init_gnutls_session(&session);

662

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

663

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

664

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

665

bool match = false;

666

{

667

char *interface = NULL;

668

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

669

interface))){

670

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

671

match = true;

672

break;

673

}

674

}

675

}

676

if(not match){

677

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

678

connect to the server */

679

if(debug){

680

char interface[IF_NAMESIZE];

681

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

682

perror_plus("if_indextoname");

683

} else {

684

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

685

" \"%s\"\n",

686

if_indextoname((unsigned int)if_index,

687

interface));

688

}

689

}

690

return -1;

691

}

692

}

693

694

ret = init_gnutls_session(&session, mc);

635

695

if(ret != 0){

636

696

return -1;

637

697

}

638

698

639

699

if(debug){

640

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

641

"\n", ip, port);

700

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

701

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

642

702

}

643

703

644

704

tcp_sd = socket(pf, SOCK_STREAM, 0);

670

730

}

671

731

if(ret == 0){

672

732

int e = errno;

673

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

733

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

674

734

errno = e;

675

735

goto mandos_end;

676

736

}

677

737

if(af == AF_INET6){

678

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

679

-Wconversion and

680

-Wunreachable-code */

681

738

to.in6.sin6_port = htons(port);

739

#ifdef __GNUC__

740

#pragma GCC diagnostic push

741

#pragma GCC diagnostic ignored "-Wstrict-aliasing"

742

#endif

682

743

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

683

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

684

-Wunreachable-code*/

744

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

745

#ifdef __GNUC__

746

#pragma GCC diagnostic pop

747

#endif

685

748

if(if_index == AVAHI_IF_UNSPEC){

686

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

687

" without a network interface\n");

749

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

750

" incomplete without a network interface\n");

688

751

errno = EINVAL;

689

752

goto mandos_end;

690

753

}

692

755

to.in6.sin6_scope_id = (uint32_t)if_index;

693

756

}

694

757

} else {

695

to.in.sin_port = htons(port); /* Spurious warnings from

696

-Wconversion and

697

-Wunreachable-code */

758

to.in.sin_port = htons(port);

698

759

}

699

760

700

761

if(quit_now){

708

769

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

709

770

perror_plus("if_indextoname");

710

771

} else {

711

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

712

ip, interface, port);

772

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

773

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

713

774

}

714

775

} else {

715

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

716

port);

776

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

777

ip, (uintmax_t)port);

717

778

}

718

779

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

719

780

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

729

790

perror_plus("inet_ntop");

730

791

} else {

731

792

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

732

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

793

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

733

794

}

734

795

}

735

796

}

763

824

while(true){

764

825

size_t out_size = strlen(out);

765

826

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

766

out_size - written));

827

out_size - written));

767

828

if(ret == -1){

768

829

int e = errno;

769

830

perror_plus("write");

789

850

}

790

851

791

852

if(debug){

792

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

853

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

793

854

}

794

855

795

856

if(quit_now){

796

857

errno = EINTR;

797

858

goto mandos_end;

798

859

}

799

800

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

801

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

860

861

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

862

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

863

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

864

gnutls_transport_set_ptr(session,

865

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

802

866

803

867

if(quit_now){

804

868

errno = EINTR;

815

879

816

880

if(ret != GNUTLS_E_SUCCESS){

817

881

if(debug){

818

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

882

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

819

883

gnutls_perror(ret);

820

884

}

821

885

errno = EPROTO;

825

889

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

826

890

827

891

if(debug){

828

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

829

ip);

892

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

893

" %s\n", ip);

830

894

}

831

895

832

896

while(true){

837

901

}

838

902

839

903

buffer_capacity = incbuffer(&buffer, buffer_length,

840

buffer_capacity);

904

buffer_capacity);

841

905

if(buffer_capacity == 0){

842

906

int e = errno;

843

907

perror_plus("incbuffer");

870

934

}

871

935

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

872

936

if(ret < 0){

873

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

937

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

938

"***\n");

874

939

gnutls_perror(ret);

875

940

errno = EPROTO;

876

941

goto mandos_end;

877

942

}

878

943

break;

879

944

default:

880

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

881

" encrypted session with Mandos server\n");

945

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

946

" encrypted session with Mandos server\n");

882

947

gnutls_bye(session, GNUTLS_SHUT_RDWR);

883

948

errno = EIO;

884

949

goto mandos_end;

889

954

}

890

955

891

956

if(debug){

892

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

957

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

893

958

}

894

959

895

960

if(quit_now){

907

972

908

973

if(buffer_length > 0){

909

974

ssize_t decrypted_buffer_size;

910

decrypted_buffer_size = pgp_packet_decrypt(buffer,

911

buffer_length,

912

&decrypted_buffer);

975

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

976

&decrypted_buffer, mc);

913

977

if(decrypted_buffer_size >= 0){

914

978

915

979

written = 0;

925

989

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

926

990

int e = errno;

927

991

if(debug){

928

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

929

strerror(errno));

992

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

993

strerror(errno));

930

994

}

931

995

errno = e;

932

996

goto mandos_end;

976

1040

AVAHI_GCC_UNUSED AvahiStringList *txt,

977

1041

AVAHI_GCC_UNUSED AvahiLookupResultFlags

978

1042

flags,

979

AVAHI_GCC_UNUSED void* userdata){

980

assert(r);

1043

void* mc){

1044

if(r == NULL){

1045

return;

1046

}

981

1047

982

1048

/* Called whenever a service has been resolved successfully or

983

1049

timed out */

989

1055

switch(event){

990

1056

default:

991

1057

case AVAHI_RESOLVER_FAILURE:

992

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

993

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

994

avahi_strerror(avahi_server_errno(mc.server)));

1058

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

1059

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

1060

domain,

1061

avahi_strerror(avahi_server_errno

1062

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

995

1063

break;

996

1064

997

1065

case AVAHI_RESOLVER_FOUND:

999

1067

char ip[AVAHI_ADDRESS_STR_MAX];

1000

1068

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

1001

1069

if(debug){

1002

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

1003

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

1004

ip, (intmax_t)interface, port);

1070

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

1071

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

1072

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

1005

1073

}

1006

int ret = start_mandos_communication(ip, port, interface,

1007

avahi_proto_to_af(proto));

1074

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

1075

interface,

1076

avahi_proto_to_af(proto),

1077

mc);

1008

1078

if(ret == 0){

1009

avahi_simple_poll_quit(mc.simple_poll);

1079

avahi_simple_poll_quit(simple_poll);

1010

1080

} else {

1011

ret = add_server(ip, port, interface,

1012

avahi_proto_to_af(proto));

1081

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

1082

avahi_proto_to_af(proto),

1083

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

1084

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

1085

" list\n", name);

1086

}

1013

1087

}

1014

1088

}

1015

1089

}

1025

1099

const char *domain,

1026

1100

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1027

1101

flags,

1028

AVAHI_GCC_UNUSED void* userdata){

1029

assert(b);

1102

void* mc){

1103

if(b == NULL){

1104

return;

1105

}

1030

1106

1031

1107

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

1032

1108

is removed from the LAN */

1039

1115

default:

1040

1116

case AVAHI_BROWSER_FAILURE:

1041

1117

1042

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

1043

avahi_strerror(avahi_server_errno(mc.server)));

1044

avahi_simple_poll_quit(mc.simple_poll);

1118

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

1119

avahi_strerror(avahi_server_errno

1120

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

1121

avahi_simple_poll_quit(simple_poll);

1045

1122

return;

1046

1123

1047

1124

case AVAHI_BROWSER_NEW:

1050

1127

the callback function is called the Avahi server will free the

1051

1128

resolver for us. */

1052

1129

1053

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

1054

name, type, domain, protocol, 0,

1055

resolve_callback, NULL) == NULL)

1056

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

1057

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

1130

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

1131

interface, protocol, name, type,

1132

domain, protocol, 0,

1133

resolve_callback, mc) == NULL)

1134

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

1135

" %s\n", name,

1136

avahi_strerror(avahi_server_errno

1137

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

1058

1138

break;

1059

1139

1060

1140

case AVAHI_BROWSER_REMOVE:

1063

1143

case AVAHI_BROWSER_ALL_FOR_NOW:

1064

1144

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1065

1145

if(debug){

1066

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

1146

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

1147

" searching...\n");

1067

1148

}

1068

1149

break;

1069

1150

}

1070

1151

}

1071

1152

1072

/* Signal handler that stops main loop after sigterm has been called */

1153

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

1073

1154

static void handle_sigterm(int sig){

1074

1155

if(quit_now){

1075

1156

return;

1078

1159

signal_received = sig;

1079

1160

int old_errno = errno;

1080

1161

/* set main loop to exit */

1081

if(mc.simple_poll != NULL){

1082

avahi_simple_poll_quit(mc.simple_poll);

1162

if(simple_poll != NULL){

1163

avahi_simple_poll_quit(simple_poll);

1083

1164

}

1084

1165

errno = old_errno;

1085

1166

}

1086

1167

1168

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

1169

int ret;

1170

error_t ret_errno;

1171

1172

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

1173

if(s < 0){

1174

ret_errno = errno;

1175

perror_plus("socket");

1176

errno = ret_errno;

1177

return false;

1178

}

1179

strcpy(ifr->ifr_name, ifname);

1180

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1181

if(ret == -1){

1182

if(debug){

1183

ret_errno = errno;

1184

perror_plus("ioctl SIOCGIFFLAGS");

1185

errno = ret_errno;

1186

}

1187

return false;

1188

}

1189

return true;

1190

}

1191

1192

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

1193

1194

/* Reject the loopback device */

1195

if(ifr->ifr_flags & IFF_LOOPBACK){

1196

if(debug){

1197

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

1198

ifname);

1199

}

1200

return false;

1201

}

1202

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

1203

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

1204

if(debug){

1205

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

1206

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

1207

}

1208

return true;

1209

}

1210

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

1211

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

1212

if(debug){

1213

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1214

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

1215

}

1216

return false;

1217

}

1218

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

1219

if(ifr->ifr_flags & IFF_NOARP){

1220

if(debug){

1221

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

1222

ifname);

1223

}

1224

return false;

1225

}

1226

1227

/* Accept this device */

1228

if(debug){

1229

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

1230

}

1231

return true;

1232

}

1233

1087

1234

/*

1088

1235

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

1089

1236

* corresponds to an acceptable network device.

1090

1237

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

1091

1238

*/

1092

1239

int good_interface(const struct dirent *if_entry){

1093

ssize_t ssret;

1094

char *flagname = NULL;

1095

1240

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

1096

1241

return 0;

1097

1242

}

1098

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

1099

if_entry->d_name);

1100

if(ret < 0){

1101

perror_plus("asprintf");

1102

return 0;

1103

}

1104

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

1105

if(flags_fd == -1){

1106

perror_plus("open");

1107

free(flagname);

1108

return 0;

1109

}

1110

free(flagname);

1111

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

1112

/* read line from flags_fd */

1113

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

1114

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

1115

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

1116

if(flagstring == NULL){

1117

perror_plus("malloc");

1118

close(flags_fd);

1119

return 0;

1120

}

1121

while(to_read > 0){

1122

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

1123

(size_t)to_read));

1124

if(ssret == -1){

1125

perror_plus("read");

1126

free(flagstring);

1127

close(flags_fd);

1128

return 0;

1129

}

1130

to_read -= ssret;

1131

if(ssret == 0){

1132

break;

1133

}

1134

}

1135

close(flags_fd);

1136

intmax_t tmpmax;

1137

char *tmp;

1138

errno = 0;

1139

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

1140

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

1141

and not (isspace(*tmp)))

1142

or tmpmax != (ifreq_flags)tmpmax){

1143

if(debug){

1144

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

1145

flagstring, if_entry->d_name);

1146

}

1147

free(flagstring);

1148

return 0;

1149

}

1150

free(flagstring);

1151

ifreq_flags flags = (ifreq_flags)tmpmax;

1152

/* Reject the loopback device */

1153

if(flags & IFF_LOOPBACK){

1154

if(debug){

1155

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

1156

if_entry->d_name);

1157

}

1158

return 0;

1159

}

1160

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

1161

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

1162

if(debug){

1163

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

1164

if_entry->d_name);

1165

}

1166

return 1;

1167

}

1168

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

1169

if(not (flags & IFF_BROADCAST)){

1170

if(debug){

1171

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

1172

if_entry->d_name);

1173

}

1174

return 0;

1175

}

1176

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

1177

if(flags & IFF_NOARP){

1178

if(debug){

1179

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

1180

if_entry->d_name);

1181

}

1182

return 0;

1183

}

1184

/* Accept this device */

1185

if(debug){

1186

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

1187

if_entry->d_name);

1243

1244

struct ifreq ifr;

1245

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

1246

if(debug){

1247

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

1248

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

1249

}

1250

return 0;

1251

}

1252

1253

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

1254

return 0;

1188

1255

}

1189

1256

return 1;

1190

1257

}

1191

1258

1259

/*

1260

* This function determines if a network interface is up.

1261

*/

1262

bool interface_is_up(const char *interface){

1263

struct ifreq ifr;

1264

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

1265

if(debug){

1266

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

1267

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

1268

}

1269

return false;

1270

}

1271

1272

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

1273

}

1274

1275

/*

1276

* This function determines if a network interface is running

1277

*/

1278

bool interface_is_running(const char *interface){

1279

struct ifreq ifr;

1280

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

1281

if(debug){

1282

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

1283

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

1284

}

1285

return false;

1286

}

1287

1288

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

1289

}

1290

1192

1291

int notdotentries(const struct dirent *direntry){

1193

1292

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

1194

1293

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

1200

1299

return 1;

1201

1300

}

1202

1301

1203

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1302

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

1303

int runnable_hook(const struct dirent *direntry){

1304

int ret;

1305

size_t sret;

1306

struct stat st;

1307

1308

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

1309

/* Empty name? */

1310

return 0;

1311

}

1312

1313

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

1314

"abcdefghijklmnopqrstuvwxyz"

1315

"0123456789"

1316

"_-");

1317

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

1318

/* Contains non-allowed characters */

1319

if(debug){

1320

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

1321

direntry->d_name);

1322

}

1323

return 0;

1324

}

1325

1326

char *fullname = NULL;

1327

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

1328

if(ret < 0){

1329

perror_plus("asprintf");

1330

return 0;

1331

}

1332

1333

ret = stat(fullname, &st);

1334

if(ret == -1){

1335

if(debug){

1336

perror_plus("Could not stat hook");

1337

}

1338

return 0;

1339

}

1340

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

1341

/* Not a regular file */

1342

if(debug){

1343

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

1344

direntry->d_name);

1345

}

1346

return 0;

1347

}

1348

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

1349

/* Not executable */

1350

if(debug){

1351

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

1352

direntry->d_name);

1353

}

1354

return 0;

1355

}

1356

if(debug){

1357

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

1358

direntry->d_name);

1359

}

1360

return 1;

1361

}

1362

1363

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1364

mandos_context *mc){

1204

1365

int ret;

1205

1366

struct timespec now;

1206

1367

struct timespec waited_time;

1207

1368

intmax_t block_time;

1208

1369

1209

1370

while(true){

1210

if(mc.current_server == NULL){

1371

if(mc->current_server == NULL){

1211

1372

if (debug){

1212

fprintf(stderr, "Wait until first server is found. No timeout!\n");

1373

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

1374

" No timeout!\n");

1213

1375

}

1214

1376

ret = avahi_simple_poll_iterate(s, -1);

1215

1377

} else {

1216

1378

if (debug){

1217

fprintf(stderr, "Check current_server if we should run it, or wait\n");

1379

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

1380

" it, or wait\n");

1218

1381

}

1219

1382

/* the current time */

1220

1383

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1224

1387

}

1225

1388

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

1226

1389

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

1227

waited_time.tv_sec = now.tv_sec - mc.current_server->last_seen.tv_sec;

1228

waited_time.tv_nsec = now.tv_nsec - mc.current_server->last_seen.tv_nsec;

1229

/* total time is 10s/10000ms. Converting to s to ms by 1000/s, and ns to ms by divind by 1000000. */

1230

block_time = (retry_interval - ((intmax_t)waited_time.tv_sec * 1000)) - ((intmax_t)waited_time.tv_nsec / 1000000);

1231

1390

waited_time.tv_sec = (now.tv_sec

1391

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

1392

waited_time.tv_nsec = (now.tv_nsec

1393

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

1394

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

1395

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

1396

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

1397

block_time = ((retry_interval

1398

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

1399

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

1400

1232

1401

if (debug){

1233

fprintf(stderr, "Blocking for %ld ms\n", block_time);

1402

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

1403

block_time);

1234

1404

}

1235

1405

1236

1406

if(block_time <= 0){

1237

ret = start_mandos_communication(mc.current_server->ip,

1238

mc.current_server->port,

1239

mc.current_server->if_index,

1240

mc.current_server->af);

1407

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

1408

mc->current_server->port,

1409

mc->current_server->if_index,

1410

mc->current_server->af, mc);

1241

1411

if(ret == 0){

1242

avahi_simple_poll_quit(mc.simple_poll);

1412

avahi_simple_poll_quit(s);

1243

1413

return 0;

1244

1414

}

1245

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

1415

ret = clock_gettime(CLOCK_MONOTONIC,

1416

&mc->current_server->last_seen);

1246

1417

if(ret == -1){

1247

1418

perror_plus("clock_gettime");

1248

1419

return -1;

1249

1420

}

1250

mc.current_server = mc.current_server->next;

1251

block_time = 0; /* call avahi to find new mandos servers, but dont block */

1421

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

1422

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

1423

servers, but don't block */

1252

1424

}

1253

1425

1254

1426

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

1255

1427

}

1256

1428

if(ret != 0){

1257

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

1429

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

1258

1430

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

1259

1431

}

1260

1432

}

1261

1433

}

1262

1434

}

1263

1435

1436

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

1437

error_t raise_privileges(void){

1438

error_t old_errno = errno;

1439

error_t ret_errno = 0;

1440

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

1441

ret_errno = errno;

1442

perror_plus("seteuid");

1443

}

1444

errno = old_errno;

1445

return ret_errno;

1446

}

1447

1448

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

1449

error_t raise_privileges_permanently(void){

1450

error_t old_errno = errno;

1451

error_t ret_errno = raise_privileges();

1452

if(ret_errno != 0){

1453

errno = old_errno;

1454

return ret_errno;

1455

}

1456

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

1457

ret_errno = errno;

1458

perror_plus("seteuid");

1459

}

1460

errno = old_errno;

1461

return ret_errno;

1462

}

1463

1464

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

1465

error_t lower_privileges(void){

1466

error_t old_errno = errno;

1467

error_t ret_errno = 0;

1468

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

1469

ret_errno = errno;

1470

perror_plus("seteuid");

1471

}

1472

errno = old_errno;

1473

return ret_errno;

1474

}

1475

1476

/* Lower privileges permanently */

1477

error_t lower_privileges_permanently(void){

1478

error_t old_errno = errno;

1479

error_t ret_errno = 0;

1480

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

1481

ret_errno = errno;

1482

perror_plus("setuid");

1483

}

1484

errno = old_errno;

1485

return ret_errno;

1486

}

1487

1488

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

1489

const float delay){

1490

struct dirent **direntries;

1491

struct dirent *direntry;

1492

int ret;

1493

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

1494

alphasort);

1495

if(numhooks == -1){

1496

if(errno == ENOENT){

1497

if(debug){

1498

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

1499

" found\n", hookdir);

1500

}

1501

} else {

1502

perror_plus("scandir");

1503

}

1504

} else {

1505

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

1506

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

1507

direntry = direntries[i];

1508

char *fullname = NULL;

1509

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

1510

if(ret < 0){

1511

perror_plus("asprintf");

1512

continue;

1513

}

1514

if(debug){

1515

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

1516

direntry->d_name);

1517

}

1518

pid_t hook_pid = fork();

1519

if(hook_pid == 0){

1520

/* Child */

1521

/* Raise privileges */

1522

raise_privileges_permanently();

1523

/* Set group */

1524

errno = 0;

1525

ret = setgid(0);

1526

if(ret == -1){

1527

perror_plus("setgid");

1528

}

1529

/* Reset supplementary groups */

1530

errno = 0;

1531

ret = setgroups(0, NULL);

1532

if(ret == -1){

1533

perror_plus("setgroups");

1534

}

1535

dup2(devnull, STDIN_FILENO);

1536

close(devnull);

1537

dup2(STDERR_FILENO, STDOUT_FILENO);

1538

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

1539

if(ret == -1){

1540

perror_plus("setenv");

1541

_exit(EX_OSERR);

1542

}

1543

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

1544

if(ret == -1){

1545

perror_plus("setenv");

1546

_exit(EX_OSERR);

1547

}

1548

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

1549

if(ret == -1){

1550

perror_plus("setenv");

1551

_exit(EX_OSERR);

1552

}

1553

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

1554

if(ret == -1){

1555

perror_plus("setenv");

1556

_exit(EX_OSERR);

1557

}

1558

char *delaystring;

1559

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

1560

if(ret == -1){

1561

perror_plus("asprintf");

1562

_exit(EX_OSERR);

1563

}

1564

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

1565

if(ret == -1){

1566

free(delaystring);

1567

perror_plus("setenv");

1568

_exit(EX_OSERR);

1569

}

1570

free(delaystring);

1571

if(connect_to != NULL){

1572

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

1573

if(ret == -1){

1574

perror_plus("setenv");

1575

_exit(EX_OSERR);

1576

}

1577

}

1578

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

1579

perror_plus("execl");

1580

_exit(EXIT_FAILURE);

1581

}

1582

} else {

1583

int status;

1584

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

1585

perror_plus("waitpid");

1586

free(fullname);

1587

continue;

1588

}

1589

if(WIFEXITED(status)){

1590

if(WEXITSTATUS(status) != 0){

1591

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

1592

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

1593

WEXITSTATUS(status));

1594

free(fullname);

1595

continue;

1596

}

1597

} else if(WIFSIGNALED(status)){

1598

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

1599

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

1600

WTERMSIG(status));

1601

free(fullname);

1602

continue;

1603

} else {

1604

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

1605

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

1606

free(fullname);

1607

continue;

1608

}

1609

}

1610

free(fullname);

1611

if(debug){

1612

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

1613

direntry->d_name);

1614

}

1615

}

1616

close(devnull);

1617

}

1618

return true;

1619

}

1620

1621

error_t bring_up_interface(const char *const interface,

1622

const float delay){

1623

int sd = -1;

1624

error_t old_errno = errno;

1625

error_t ret_errno = 0;

1626

int ret, ret_setflags;

1627

struct ifreq network;

1628

unsigned int if_index = if_nametoindex(interface);

1629

if(if_index == 0){

1630

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

1631

errno = old_errno;

1632

return ENXIO;

1633

}

1634

1635

if(quit_now){

1636

errno = old_errno;

1637

return EINTR;

1638

}

1639

1640

if(not interface_is_up(interface)){

1641

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

1642

ret_errno = errno;

1643

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

1644

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

1645

return ret_errno;

1646

}

1647

network.ifr_flags |= IFF_UP;

1648

1649

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1650

if(sd < 0){

1651

ret_errno = errno;

1652

perror_plus("socket");

1653

errno = old_errno;

1654

return ret_errno;

1655

}

1656

1657

if(quit_now){

1658

close(sd);

1659

errno = old_errno;

1660

return EINTR;

1661

}

1662

1663

if(debug){

1664

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

1665

interface);

1666

}

1667

1668

/* Raise priviliges */

1669

raise_privileges();

1670

1671

#ifdef __linux__

1672

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1673

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

1674

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

1675

bool restore_loglevel = true;

1676

if(ret_linux == -1){

1677

restore_loglevel = false;

1678

perror_plus("klogctl");

1679

}

1680

#endif /* __linux__ */

1681

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

1682

ret_errno = errno;

1683

#ifdef __linux__

1684

if(restore_loglevel){

1685

ret_linux = klogctl(7, NULL, 0);

1686

if(ret_linux == -1){

1687

perror_plus("klogctl");

1688

}

1689

}

1690

#endif /* __linux__ */

1691

1692

/* Lower privileges */

1693

lower_privileges();

1694

1695

/* Close the socket */

1696

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

1697

if(ret == -1){

1698

perror_plus("close");

1699

}

1700

1701

if(ret_setflags == -1){

1702

errno = ret_errno;

1703

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1704

errno = old_errno;

1705

return ret_errno;

1706

}

1707

} else if(debug){

1708

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

1709

interface);

1710

}

1711

1712

/* Sleep checking until interface is running.

1713

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

1714

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

1715

if(interface_is_running(interface)){

1716

break;

1717

}

1718

struct timespec sleeptime = { .tv_nsec = 250000000 };

1719

ret = nanosleep(&sleeptime, NULL);

1720

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

1721

perror_plus("nanosleep");

1722

}

1723

}

1724

1725

errno = old_errno;

1726

return 0;

1727

}

1728

1729

error_t take_down_interface(const char *const interface){

1730

int sd = -1;

1731

error_t old_errno = errno;

1732

error_t ret_errno = 0;

1733

int ret, ret_setflags;

1734

struct ifreq network;

1735

unsigned int if_index = if_nametoindex(interface);

1736

if(if_index == 0){

1737

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

1738

errno = old_errno;

1739

return ENXIO;

1740

}

1741

if(interface_is_up(interface)){

1742

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

1743

ret_errno = errno;

1744

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

1745

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

1746

return ret_errno;

1747

}

1748

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

1749

1750

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1751

if(sd < 0){

1752

ret_errno = errno;

1753

perror_plus("socket");

1754

errno = old_errno;

1755

return ret_errno;

1756

}

1757

1758

if(debug){

1759

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

1760

interface);

1761

}

1762

1763

/* Raise priviliges */

1764

raise_privileges();

1765

1766

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

1767

ret_errno = errno;

1768

1769

/* Lower privileges */

1770

lower_privileges();

1771

1772

/* Close the socket */

1773

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

1774

if(ret == -1){

1775

perror_plus("close");

1776

}

1777

1778

if(ret_setflags == -1){

1779

errno = ret_errno;

1780

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1781

errno = old_errno;

1782

return ret_errno;

1783

}

1784

} else if(debug){

1785

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

1786

interface);

1787

}

1788

1789

errno = old_errno;

1790

return 0;

1791

}

1792

1264

1793

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

1794

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

1795

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

1796

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

1797

.interfaces = NULL, .interfaces_size = 0 };

1265

1798

AvahiSServiceBrowser *sb = NULL;

1266

int error;

1799

error_t ret_errno;

1267

1800

int ret;

1268

1801

intmax_t tmpmax;

1269

1802

char *tmp;

1270

1803

int exitcode = EXIT_SUCCESS;

1271

const char *interface = "";

1272

struct ifreq network;

1273

int sd = -1;

1274

bool take_down_interface = false;

1275

uid_t uid;

1276

gid_t gid;

1804

char *interfaces_to_take_down = NULL;

1805

size_t interfaces_to_take_down_size = 0;

1277

1806

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

1278

1807

bool tempdir_created = false;

1279

1808

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1280

1809

const char *seckey = PATHDIR "/" SECKEY;

1281

1810

const char *pubkey = PATHDIR "/" PUBKEY;

1811

char *interfaces_hooks = NULL;

1812

size_t interfaces_hooks_size = 0;

1282

1813

1283

1814

bool gnutls_initialized = false;

1284

1815

bool gpgme_initialized = false;

1285

1816

float delay = 2.5f;

1286

double retry_interval = 10; /* 10s between retrying a server and checking again*/

1817

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

1818

retrying the same server again */

1287

1819

1288

1820

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1289

1821

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1345

1877

.group = 2 },

1346

1878

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

1347

1879

.arg = "SECONDS",

1348

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

1880

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

1881

.group = 2 },

1882

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

1883

.arg = "DIR",

1884

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

1349

1885

.group = 2 },

1350

1886

/*

1351

1887

* These reproduce what we would get without ARGP_NO_HELP

1370

1906

connect_to = arg;

1371

1907

break;

1372

1908

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

1373

interface = arg;

1909

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

1910

arg, (int)',');

1911

if(ret_errno != 0){

1912

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

1913

}

1374

1914

break;

1375

1915

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

1376

1916

seckey = arg;

1400

1940

errno = 0;

1401

1941

retry_interval = strtod(arg, &tmp);

1402

1942

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

1403

or (retry_interval * 1000) > INT_MAX){

1943

or (retry_interval * 1000) > INT_MAX

1944

or retry_interval < 0){

1404

1945

argp_error(state, "Bad retry interval");

1405

1946

}

1406

1947

break;

1948

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

1949

hookdir = arg;

1950

break;

1407

1951

/*

1408

1952

* These reproduce what we would get without ARGP_NO_HELP

1409

1953

*/

1415

1959

argp_state_help(state, state->out_stream,

1416

1960

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1417

1961

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

1418

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

1962

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

1419

1963

exit(argp_err_exit_status);

1420

1964

break;

1421

1965

default:

1444

1988

goto end;

1445

1989

}

1446

1990

}

1991

1992

{

1993

/* Work around Debian bug #633582:

1994

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

1995

1996

/* Re-raise priviliges */

1997

if(raise_privileges() == 0){

1998

struct stat st;

1999

2000

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

2001

int seckey_fd = open(seckey, O_RDONLY);

2002

if(seckey_fd == -1){

2003

perror_plus("open");

2004

} else {

2005

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

2006

if(ret == -1){

2007

perror_plus("fstat");

2008

} else {

2009

if(S_ISREG(st.st_mode)

2010

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

2011

ret = fchown(seckey_fd, uid, gid);

2012

if(ret == -1){

2013

perror_plus("fchown");

2014

}

2015

}

2016

}

2017

TEMP_FAILURE_RETRY(close(seckey_fd));

2018

}

2019

}

2020

2021

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

2022

int pubkey_fd = open(pubkey, O_RDONLY);

2023

if(pubkey_fd == -1){

2024

perror_plus("open");

2025

} else {

2026

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

2027

if(ret == -1){

2028

perror_plus("fstat");

2029

} else {

2030

if(S_ISREG(st.st_mode)

2031

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

2032

ret = fchown(pubkey_fd, uid, gid);

2033

if(ret == -1){

2034

perror_plus("fchown");

2035

}

2036

}

2037

}

2038

TEMP_FAILURE_RETRY(close(pubkey_fd));

2039

}

2040

}

2041

2042

/* Lower privileges */

2043

lower_privileges();

2044

}

2045

}

2046

2047

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

2048

{

2049

char *interface = NULL;

2050

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

2051

interface))){

2052

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

2053

and if_nametoindex(interface) == 0){

2054

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

2055

fprintf_plus(stderr, "Not using nonexisting interface"

2056

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

2057

}

2058

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

2059

interface = NULL;

2060

}

2061

}

2062

}

2063

2064

/* Run network hooks */

2065

{

2066

if(mc.interfaces != NULL){

2067

interfaces_hooks = malloc(mc.interfaces_size);

2068

if(interfaces_hooks == NULL){

2069

perror_plus("malloc");

2070

goto end;

2071

}

2072

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

2073

interfaces_hooks_size = mc.interfaces_size;

2074

argz_stringify(interfaces_hooks, interfaces_hooks_size,

2075

(int)',');

2076

}

2077

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

2078

interfaces_hooks : "", delay)){

2079

goto end;

2080

}

2081

}

1447

2082

1448

2083

if(not debug){

1449

2084

avahi_set_log_function(empty_log);

1450

2085

}

1451

1452

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

1453

struct dirent **direntries;

1454

ret = scandir(sys_class_net, &direntries, good_interface,

1455

alphasort);

1456

if(ret >= 1){

1457

/* Pick the first good interface */

1458

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

1459

if(debug){

1460

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

1461

}

1462

if(interface == NULL){

1463

perror_plus("malloc");

1464

free(direntries);

1465

exitcode = EXIT_FAILURE;

1466

goto end;

1467

}

1468

free(direntries);

1469

} else {

1470

free(direntries);

1471

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

1472

exitcode = EXIT_FAILURE;

1473

goto end;

1474

}

1475

}

1476

2086

1477

2087

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

1478

2088

from the signal handler */

1479

2089

/* Initialize the pseudo-RNG for Avahi */

1480

2090

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

1481

mc.simple_poll = avahi_simple_poll_new();

1482

if(mc.simple_poll == NULL){

1483

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

2091

simple_poll = avahi_simple_poll_new();

2092

if(simple_poll == NULL){

2093

fprintf_plus(stderr,

2094

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

1484

2095

exitcode = EX_UNAVAILABLE;

1485

2096

goto end;

1486

2097

}

1548

2159

}

1549

2160

}

1550

2161

1551

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

1552

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

1553

if_index = (AvahiIfIndex) if_nametoindex(interface);

1554

if(if_index == 0){

1555

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

1556

exitcode = EX_UNAVAILABLE;

1557

goto end;

1558

}

1559

1560

if(quit_now){

1561

goto end;

1562

}

1563

1564

/* Re-raise priviliges */

1565

errno = 0;

1566

ret = seteuid(0);

1567

if(ret == -1){

1568

perror_plus("seteuid");

1569

}

1570

1571

#ifdef __linux__

1572

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1573

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

1574

ret = klogctl(8, NULL, 5);

1575

bool restore_loglevel = true;

1576

if(ret == -1){

1577

restore_loglevel = false;

1578

perror_plus("klogctl");

1579

}

1580

#endif /* __linux__ */

1581

1582

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1583

if(sd < 0){

1584

perror_plus("socket");

1585

exitcode = EX_OSERR;

1586

#ifdef __linux__

1587

if(restore_loglevel){

1588

ret = klogctl(7, NULL, 0);

1589

if(ret == -1){

1590

perror_plus("klogctl");

1591

}

1592

}

1593

#endif /* __linux__ */

1594

/* Lower privileges */

1595

errno = 0;

1596

ret = seteuid(uid);

1597

if(ret == -1){

1598

perror_plus("seteuid");

1599

}

1600

goto end;

1601

}

1602

strcpy(network.ifr_name, interface);

1603

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

1604

if(ret == -1){

1605

perror_plus("ioctl SIOCGIFFLAGS");

1606

#ifdef __linux__

1607

if(restore_loglevel){

1608

ret = klogctl(7, NULL, 0);

1609

if(ret == -1){

1610

perror_plus("klogctl");

1611

}

1612

}

1613

#endif /* __linux__ */

1614

exitcode = EX_OSERR;

1615

/* Lower privileges */

1616

errno = 0;

1617

ret = seteuid(uid);

1618

if(ret == -1){

1619

perror_plus("seteuid");

1620

}

1621

goto end;

1622

}

1623

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

1624

network.ifr_flags |= IFF_UP;

1625

take_down_interface = true;

1626

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

1627

if(ret == -1){

1628

take_down_interface = false;

1629

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1630

exitcode = EX_OSERR;

1631

#ifdef __linux__

1632

if(restore_loglevel){

1633

ret = klogctl(7, NULL, 0);

1634

if(ret == -1){

1635

perror_plus("klogctl");

2162

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

2163

if(mc.interfaces == NULL){

2164

struct dirent **direntries;

2165

/* Look for any good interfaces */

2166

ret = scandir(sys_class_net, &direntries, good_interface,

2167

alphasort);

2168

if(ret >= 1){

2169

/* Add all found interfaces to interfaces list */

2170

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

2171

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

2172

direntries[i]->d_name);

2173

if(ret_errno != 0){

2174

perror_plus("argz_add");

2175

continue;

2176

}

2177

if(debug){

2178

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

2179

direntries[i]->d_name);

2180

}

2181

}

2182

free(direntries);

2183

} else {

2184

free(direntries);

2185

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

2186

exitcode = EXIT_FAILURE;

2187

goto end;

2188

}

2189

}

2190

2191

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

2192

{

2193

char *interface = NULL;

2194

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

2195

interface))){

2196

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

2197

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

2198

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

2199

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

2200

interface);

2201

interface = NULL;

2202

while((interface = argz_next(mc.interfaces,

2203

mc.interfaces_size, interface))){

2204

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

2205

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

2206

interface);

2207

interface = NULL;

1636

2208

}

1637

2209

}

1638

#endif /* __linux__ */

1639

/* Lower privileges */

1640

errno = 0;

1641

ret = seteuid(uid);

1642

if(ret == -1){

1643

perror_plus("seteuid");

1644

}

1645

goto end;

1646

}

1647

}

1648

/* sleep checking until interface is running. Check every 0.25s, up to total time of delay */

1649

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

1650

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

1651

if(ret == -1){

1652

perror_plus("ioctl SIOCGIFFLAGS");

1653

} else if(network.ifr_flags & IFF_RUNNING){

1654

2210

break;

1655

2211

}

1656

struct timespec sleeptime = { .tv_nsec = 250000000 };

1657

ret = nanosleep(&sleeptime, NULL);

1658

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

1659

perror_plus("nanosleep");

1660

}

1661

}

1662

if(not take_down_interface){

1663

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

1664

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

1665

if(ret == -1){

1666

perror_plus("close");

1667

}

1668

}

1669

#ifdef __linux__

1670

if(restore_loglevel){

1671

/* Restores kernel loglevel to default */

1672

ret = klogctl(7, NULL, 0);

1673

if(ret == -1){

1674

perror_plus("klogctl");

1675

}

1676

}

1677

#endif /* __linux__ */

1678

/* Lower privileges */

1679

errno = 0;

1680

if(take_down_interface){

1681

/* Lower privileges */

1682

ret = seteuid(uid);

1683

if(ret == -1){

1684

perror_plus("seteuid");

1685

}

1686

} else {

1687

/* Lower privileges permanently */

1688

ret = setuid(uid);

1689

if(ret == -1){

1690

perror_plus("setuid");

1691

}

1692

}

2212

bool interface_was_up = interface_is_up(interface);

2213

ret = bring_up_interface(interface, delay);

2214

if(not interface_was_up){

2215

if(ret != 0){

2216

errno = ret;

2217

perror_plus("Failed to bring up interface");

2218

} else {

2219

ret_errno = argz_add(&interfaces_to_take_down,

2220

&interfaces_to_take_down_size,

2221

interface);

2222

}

2223

}

2224

}

2225

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

2226

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

2227

}

2228

}

2229

2230

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

2231

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

2232

if(debug){

2233

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

2234

mc.interfaces);

2235

}

2236

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

1693

2237

}

1694

2238

1695

2239

if(quit_now){

1696

2240

goto end;

1697

2241

}

1698

2242

1699

ret = init_gnutls_global(pubkey, seckey);

2243

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

1700

2244

if(ret == -1){

1701

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

2245

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

1702

2246

exitcode = EX_UNAVAILABLE;

1703

2247

goto end;

1704

2248

} else {

1719

2263

goto end;

1720

2264

}

1721

2265

1722

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

1723

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

2266

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

2267

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

1724

2268

exitcode = EX_UNAVAILABLE;

1725

2269

goto end;

1726

2270

} else {

1735

2279

/* Connect directly, do not use Zeroconf */

1736

2280

/* (Mainly meant for debugging) */

1737

2281

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

2282

1738

2283

if(address == NULL){

1739

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

2284

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

1740

2285

exitcode = EX_USAGE;

1741

2286

goto end;

1742

2287

}

1745

2290

goto end;

1746

2291

}

1747

2292

1748

uint16_t port;

2293

in_port_t port;

1749

2294

errno = 0;

1750

2295

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

1751

2296

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

1752

or tmpmax != (uint16_t)tmpmax){

1753

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

2297

or tmpmax != (in_port_t)tmpmax){

2298

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

1754

2299

exitcode = EX_USAGE;

1755

2300

goto end;

1756

2301

}

1757

2302

1758

2303

if(quit_now){

1759

2304

goto end;

1760

2305

}

1761

2306

1762

port = (uint16_t)tmpmax;

2307

port = (in_port_t)tmpmax;

1763

2308

*address = '\0';

1764

address = connect_to;

1765

2309

/* Colon in address indicates IPv6 */

1766

2310

int af;

1767

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

2311

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

1768

2312

af = AF_INET6;

2313

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

2314

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

2315

{

2316

connect_to++;

2317

address[-1] = '\0';

2318

}

1769

2319

} else {

1770

2320

af = AF_INET;

1771

2321

}

2322

address = connect_to;

1772

2323

1773

2324

if(quit_now){

1774

2325

goto end;

1775

2326

}

1776

2327

1777

2328

while(not quit_now){

1778

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

2329

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

2330

&mc);

1779

2331

if(quit_now or ret == 0){

1780

2332

break;

1781

2333

}

1782

sleep((int)retry_interval or 1);

1783

};

1784

2334

if(debug){

2335

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

2336

(int)retry_interval);

2337

}

2338

sleep((unsigned int)retry_interval);

2339

}

2340

1785

2341

if (not quit_now){

1786

2342

exitcode = EXIT_SUCCESS;

1787

2343

}

1788

2344

1789

2345

goto end;

1790

2346

}

1791

2347

1803

2359

config.publish_domain = 0;

1804

2360

1805

2361

/* Allocate a new server */

1806

mc.server = avahi_server_new(avahi_simple_poll_get

1807

(mc.simple_poll), &config, NULL,

1808

NULL, &error);

2362

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2363

&config, NULL, NULL, &ret_errno);

1809

2364

1810

2365

/* Free the Avahi configuration data */

1811

2366

avahi_server_config_free(&config);

1813

2368

1814

2369

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

1815

2370

if(mc.server == NULL){

1816

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

1817

avahi_strerror(error));

2371

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

2372

avahi_strerror(ret_errno));

1818

2373

exitcode = EX_UNAVAILABLE;

1819

2374

goto end;

1820

2375

}

1826

2381

/* Create the Avahi service browser */

1827

2382

sb = avahi_s_service_browser_new(mc.server, if_index,

1828

2383

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1829

NULL, 0, browse_callback, NULL);

2384

NULL, 0, browse_callback,

2385

(void *)&mc);

1830

2386

if(sb == NULL){

1831

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

1832

avahi_strerror(avahi_server_errno(mc.server)));

2387

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

2388

avahi_strerror(avahi_server_errno(mc.server)));

1833

2389

exitcode = EX_UNAVAILABLE;

1834

2390

goto end;

1835

2391

}

1841

2397

/* Run the main loop */

1842

2398

1843

2399

if(debug){

1844

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

2400

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

1845

2401

}

1846

2402

1847

ret = avahi_loop_with_timeout(mc.simple_poll, (int)(retry_interval * 1000));

2403

ret = avahi_loop_with_timeout(simple_poll,

2404

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

1848

2405

if(debug){

1849

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

1850

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

2406

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

2407

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

1851

2408

}

1852

2409

1853

2410

end:

1854

2411

1855

2412

if(debug){

1856

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

2413

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

1857

2414

}

1858

2415

1859

2416

/* Cleanup things */

2417

free(mc.interfaces);

2418

1860

2419

if(sb != NULL)

1861

2420

avahi_s_service_browser_free(sb);

1862

2421

1863

2422

if(mc.server != NULL)

1864

2423

avahi_server_free(mc.server);

1865

2424

1866

if(mc.simple_poll != NULL)

1867

avahi_simple_poll_free(mc.simple_poll);

2425

if(simple_poll != NULL)

2426

avahi_simple_poll_free(simple_poll);

1868

2427

1869

2428

if(gnutls_initialized){

1870

2429

gnutls_certificate_free_credentials(mc.cred);

1875

2434

if(gpgme_initialized){

1876

2435

gpgme_release(mc.ctx);

1877

2436

}

1878

1879

/* cleans up the circular linked list of mandos servers the client has seen */

2437

2438

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

2439

has seen */

1880

2440

if(mc.current_server != NULL){

1881

2441

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

1882

2442

while(mc.current_server != NULL){

1886

2446

}

1887

2447

}

1888

2448

1889

/* Take down the network interface */

1890

if(take_down_interface){

1891

/* Re-raise priviliges */

1892

errno = 0;

1893

ret = seteuid(0);

1894

if(ret == -1){

1895

perror_plus("seteuid");

1896

}

1897

if(geteuid() == 0){

1898

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

1899

if(ret == -1){

1900

perror_plus("ioctl SIOCGIFFLAGS");

1901

} else if(network.ifr_flags & IFF_UP) {

1902

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

1903

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

1904

if(ret == -1){

1905

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2449

/* Re-raise priviliges */

2450

{

2451

raise_privileges();

2452

2453

/* Run network hooks */

2454

run_network_hooks("stop", interfaces_hooks != NULL ?

2455

interfaces_hooks : "", delay);

2456

2457

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

2458

{

2459

char *interface = NULL;

2460

while((interface=argz_next(interfaces_to_take_down,

2461

interfaces_to_take_down_size,

2462

interface))){

2463

ret_errno = take_down_interface(interface);

2464

if(ret_errno != 0){

2465

errno = ret_errno;

2466

perror_plus("Failed to take down interface");

1906

2467

}

1907

2468

}

1908

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

1909

if(ret == -1){

1910

perror_plus("close");

1911

}

1912

/* Lower privileges permanently */

1913

errno = 0;

1914

ret = setuid(uid);

1915

if(ret == -1){

1916

perror_plus("setuid");

2469

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

2470

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

2471

" down\n");

1917

2472

}

1918

2473

}

2474

2475

lower_privileges_permanently();

1919

2476

}

1920

2477

2478

free(interfaces_to_take_down);

2479

free(interfaces_hooks);

2480

1921

2481

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

1922

2482

if(tempdir_created){

1923

2483

struct dirent **direntries = NULL;

1924

2484

struct dirent *direntry = NULL;

1925

ret = scandir(tempdir, &direntries, notdotentries, alphasort);

1926

if (ret > 0){

1927

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

2485

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

2486

alphasort);

2487

if (numentries > 0){

2488

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

1928

2489

direntry = direntries[i];

1929

2490

char *fullname = NULL;

1930

2491

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

1935

2496

}

1936

2497

ret = remove(fullname);

1937

2498

if(ret == -1){

1938

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

1939

strerror(errno));

2499

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

2500

strerror(errno));

1940

2501

}

1941

2502

free(fullname);

1942

2503

}

1943

2504

}

1944

2505

1945

/* need to be cleaned even if ret == 0 because man page dont specify */

2506

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

1946

2507

free(direntries);

1947

if (ret == -1){

2508

if (numentries == -1){

1948

2509

perror_plus("scandir");

1949

2510

}

1950

2511

ret = rmdir(tempdir);