/mandos/release : revision 237.7.214

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

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*

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* Everything else is

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*

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

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

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* along with this program. If not, see

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

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*

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

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

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*/

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

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

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stdout, ferror(), remove() */

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

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

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

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

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strtof(), abort() */

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sockaddr_in6, PF_INET6,

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SOCK_STREAM, uid_t, gid_t, open(),

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opendir(), DIR */

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

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

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

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inet_pton(), connect() */

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

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*/

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

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strtoimax() */

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

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

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

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program_invocation_short_name */

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

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

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SIOCSIFFLAGS, if_indextoname(),

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*/

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

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

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setgid(), pause() */

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

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

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

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

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

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argp_state, struct argp,

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raise() */

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

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EX_NOHOST, EX_IOERR, EX_PROTOCOL */

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

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WEXITSTATUS(), WTERMSIG() */

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

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

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argz_delete(), argz_append(),

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argz_stringify(), argz_add(),

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argz_count() */

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#ifdef __linux__

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#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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#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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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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139

char *connect_to = NULL;

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const char *hookdir = HOOKDIR;

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uid_t uid = 65534;

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gid_t gid = 65534;

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144

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

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typedef struct server{

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const char *ip;

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in_port_t port;

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AvahiIfIndex if_index;

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int af;

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struct timespec last_seen;

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struct server *next;

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struct server *prev;

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} server;

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

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156

typedef struct {

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AvahiSimplePoll *simple_poll;

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157

AvahiServer *server;

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gnutls_certificate_credentials_t cred;

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159

unsigned int dh_bits;

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gnutls_dh_params_t dh_params;

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161

const char *priority;

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162

gpgme_ctx_t ctx;

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server *current_server;

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char *interfaces;

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size_t interfaces_size;

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} 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" };

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/* global so signal handler can reach it*/

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AvahiSimplePoll *simple_poll;

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170

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sig_atomic_t quit_now = 0;

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int signal_received = 0;

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173

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/* Function to use when printing errors */

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void perror_plus(const char *print_text){

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int e = errno;

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

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program_invocation_short_name);

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errno = e;

180

perror(print_text);

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}

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

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

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va_list ap;

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va_start (ap, format);

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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

152

193

/*

153

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,

155

196

* "buffer_length" is how much is already used.

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197

*/

157

198

size_t incbuffer(char **buffer, size_t buffer_length,

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size_t buffer_capacity){

199

size_t buffer_capacity){

159

200

if(buffer_length + BUFFER_SIZE > buffer_capacity){

160

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

161

if(buffer == NULL){

201

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

202

if(new_buf == NULL){

203

int old_errno = errno;

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free(*buffer);

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errno = old_errno;

206

*buffer = NULL;

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return 0;

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208

}

209

*buffer = new_buf;

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buffer_capacity += BUFFER_SIZE;

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211

}

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212

return buffer_capacity;

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213

}

168

214

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

216

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

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int af, server **current_server){

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int ret;

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

220

if(new_server == NULL){

221

perror_plus("malloc");

222

return false;

223

}

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

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.port = port,

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.if_index = if_index,

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.af = af };

228

if(new_server->ip == NULL){

229

perror_plus("strdup");

230

return false;

231

}

232

/* Special case of first server */

233

if(*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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*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 = *current_server;

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

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new_server->prev->next = new_server;

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(*current_server)->prev = new_server;

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}

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

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if(ret == -1){

246

perror_plus("clock_gettime");

247

return false;

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}

249

return true;

250

}

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/*

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253

* Initialize GPGME.

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254

*/

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static bool init_gpgme(const char *seckey,

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const char *pubkey, const char *tempdir){

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

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const char *tempdir, mandos_context *mc){

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257

gpgme_error_t rc;

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258

gpgme_engine_info_t engine_info;

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259

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178

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/*

179

261

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

180

262

*/

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

187

269

if(fd == -1){

188

perror("open");

270

perror_plus("open");

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271

return false;

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272

}

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rc = gpgme_data_new_from_fd(&pgp_data, fd);

193

275

if(rc != GPG_ERR_NO_ERROR){

194

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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

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289

if(ret == -1){

208

perror("close");

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perror_plus("close");

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}

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gpgme_data_release(pgp_data);

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return true;

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}

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if(debug){

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

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

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}

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/* Init GPGME */

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gpgme_check_version(NULL);

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rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

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303

if(rc != GPG_ERR_NO_ERROR){

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

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gpgme_strsource(rc), gpgme_strerror(rc));

304

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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306

return false;

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307

}

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308

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

309

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

228

310

rc = gpgme_get_engine_info(&engine_info);

229

311

if(rc != GPG_ERR_NO_ERROR){

230

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

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gpgme_strsource(rc), gpgme_strerror(rc));

312

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

313

gpgme_strsource(rc), gpgme_strerror(rc));

232

314

return false;

233

315

}

234

316

while(engine_info != NULL){

240

322

engine_info = engine_info->next;

241

323

}

242

324

if(engine_info == NULL){

243

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

325

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

326

tempdir);

244

327

return false;

245

328

}

246

329

247

330

/* Create new GPGME "context" */

248

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

331

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

249

332

if(rc != GPG_ERR_NO_ERROR){

250

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

251

gpgme_strsource(rc), gpgme_strerror(rc));

333

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

334

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

335

gpgme_strerror(rc));

252

336

return false;

253

337

}

254

338

265

349

*/

266

350

static ssize_t pgp_packet_decrypt(const char *cryptotext,

267

351

size_t crypto_size,

268

char **plaintext){

352

char **plaintext,

353

mandos_context *mc){

269

354

gpgme_data_t dh_crypto, dh_plain;

270

355

gpgme_error_t rc;

271

356

ssize_t ret;

273

358

ssize_t plaintext_length = 0;

274

359

275

360

if(debug){

276

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

361

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

277

362

}

278

363

279

364

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

280

365

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

281

366

0);

282

367

if(rc != GPG_ERR_NO_ERROR){

283

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

284

gpgme_strsource(rc), gpgme_strerror(rc));

368

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

369

gpgme_strsource(rc), gpgme_strerror(rc));

285

370

return -1;

286

371

}

287

372

288

373

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

289

374

rc = gpgme_data_new(&dh_plain);

290

375

if(rc != GPG_ERR_NO_ERROR){

291

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

292

gpgme_strsource(rc), gpgme_strerror(rc));

376

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

377

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

378

gpgme_strsource(rc), gpgme_strerror(rc));

293

379

gpgme_data_release(dh_crypto);

294

380

return -1;

295

381

}

296

382

297

383

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

298

384

data buffer */

299

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

385

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

300

386

if(rc != GPG_ERR_NO_ERROR){

301

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

302

gpgme_strsource(rc), gpgme_strerror(rc));

387

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

388

gpgme_strsource(rc), gpgme_strerror(rc));

303

389

plaintext_length = -1;

304

390

if(debug){

305

391

gpgme_decrypt_result_t result;

306

result = gpgme_op_decrypt_result(mc.ctx);

392

result = gpgme_op_decrypt_result(mc->ctx);

307

393

if(result == NULL){

308

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

394

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

309

395

} else {

310

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

311

result->unsupported_algorithm);

312

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

313

result->wrong_key_usage);

396

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

397

result->unsupported_algorithm);

398

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

399

result->wrong_key_usage);

314

400

if(result->file_name != NULL){

315

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

401

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

316

402

}

317

403

gpgme_recipient_t recipient;

318

404

recipient = result->recipients;

319

405

while(recipient != NULL){

320

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

321

gpgme_pubkey_algo_name(recipient->pubkey_algo));

322

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

323

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

324

recipient->status == GPG_ERR_NO_SECKEY

325

? "No" : "Yes");

406

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

407

gpgme_pubkey_algo_name

408

(recipient->pubkey_algo));

409

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

410

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

411

recipient->status == GPG_ERR_NO_SECKEY

412

? "No" : "Yes");

326

413

recipient = recipient->next;

327

414

}

328

415

}

331

418

}

332

419

333

420

if(debug){

334

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

421

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

335

422

}

336

423

337

424

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

338

425

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

339

perror("gpgme_data_seek");

426

perror_plus("gpgme_data_seek");

340

427

plaintext_length = -1;

341

428

goto decrypt_end;

342

429

}

344

431

*plaintext = NULL;

345

432

while(true){

346

433

plaintext_capacity = incbuffer(plaintext,

347

(size_t)plaintext_length,

348

plaintext_capacity);

434

(size_t)plaintext_length,

435

plaintext_capacity);

349

436

if(plaintext_capacity == 0){

350

perror("incbuffer");

351

plaintext_length = -1;

352

goto decrypt_end;

437

perror_plus("incbuffer");

438

plaintext_length = -1;

439

goto decrypt_end;

353

440

}

354

441

355

442

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

360

447

break;

361

448

}

362

449

if(ret < 0){

363

perror("gpgme_data_read");

450

perror_plus("gpgme_data_read");

364

451

plaintext_length = -1;

365

452

goto decrypt_end;

366

453

}

368

455

}

369

456

370

457

if(debug){

371

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

458

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

372

459

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

373

460

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

374

461

}

386

473

}

387

474

388

475

static const char * safer_gnutls_strerror(int value){

389

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

390

-Wunreachable-code */

476

const char *ret = gnutls_strerror(value);

391

477

if(ret == NULL)

392

478

ret = "(unknown)";

393

479

return ret;

396

482

/* GnuTLS log function callback */

397

483

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

398

484

const char* string){

399

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

485

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

400

486

}

401

487

402

488

static int init_gnutls_global(const char *pubkeyfilename,

403

const char *seckeyfilename){

489

const char *seckeyfilename,

490

mandos_context *mc){

404

491

int ret;

405

492

406

493

if(debug){

407

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

494

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

408

495

}

409

496

410

497

ret = gnutls_global_init();

411

498

if(ret != GNUTLS_E_SUCCESS){

412

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

413

safer_gnutls_strerror(ret));

499

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

500

safer_gnutls_strerror(ret));

414

501

return -1;

415

502

}

416

503

423

510

}

424

511

425

512

/* OpenPGP credentials */

426

gnutls_certificate_allocate_credentials(&mc.cred);

513

ret = gnutls_certificate_allocate_credentials(&mc->cred);

427

514

if(ret != GNUTLS_E_SUCCESS){

428

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

429

from

430

-Wunreachable-code

431

*/

432

safer_gnutls_strerror(ret));

515

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

516

safer_gnutls_strerror(ret));

433

517

gnutls_global_deinit();

434

518

return -1;

435

519

}

436

520

437

521

if(debug){

438

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

439

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

440

seckeyfilename);

522

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

523

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

524

pubkeyfilename,

525

seckeyfilename);

441

526

}

442

527

443

528

ret = gnutls_certificate_set_openpgp_key_file

444

(mc.cred, pubkeyfilename, seckeyfilename,

529

(mc->cred, pubkeyfilename, seckeyfilename,

445

530

GNUTLS_OPENPGP_FMT_BASE64);

446

531

if(ret != GNUTLS_E_SUCCESS){

447

fprintf(stderr,

448

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

449

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

450

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

451

safer_gnutls_strerror(ret));

532

fprintf_plus(stderr,

533

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

534

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

535

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

536

safer_gnutls_strerror(ret));

452

537

goto globalfail;

453

538

}

454

539

455

540

/* GnuTLS server initialization */

456

ret = gnutls_dh_params_init(&mc.dh_params);

541

ret = gnutls_dh_params_init(&mc->dh_params);

457

542

if(ret != GNUTLS_E_SUCCESS){

458

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

459

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

543

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

544

" initialization: %s\n",

545

safer_gnutls_strerror(ret));

460

546

goto globalfail;

461

547

}

462

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

548

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

463

549

if(ret != GNUTLS_E_SUCCESS){

464

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

465

safer_gnutls_strerror(ret));

550

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

551

safer_gnutls_strerror(ret));

466

552

goto globalfail;

467

553

}

468

554

469

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

555

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

470

556

471

557

return 0;

472

558

473

559

globalfail:

474

560

475

gnutls_certificate_free_credentials(mc.cred);

561

gnutls_certificate_free_credentials(mc->cred);

476

562

gnutls_global_deinit();

477

gnutls_dh_params_deinit(mc.dh_params);

563

gnutls_dh_params_deinit(mc->dh_params);

478

564

return -1;

479

565

}

480

566

481

static int init_gnutls_session(gnutls_session_t *session){

567

static int init_gnutls_session(gnutls_session_t *session,

568

mandos_context *mc){

482

569

int ret;

483

570

/* GnuTLS session creation */

484

571

do {

488

575

}

489

576

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

490

577

if(ret != GNUTLS_E_SUCCESS){

491

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

492

safer_gnutls_strerror(ret));

578

fprintf_plus(stderr,

579

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

580

safer_gnutls_strerror(ret));

493

581

}

494

582

495

583

{

496

584

const char *err;

497

585

do {

498

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

586

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

499

587

if(quit_now){

500

588

gnutls_deinit(*session);

501

589

return -1;

502

590

}

503

591

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

504

592

if(ret != GNUTLS_E_SUCCESS){

505

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

506

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

507

safer_gnutls_strerror(ret));

593

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

594

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

595

safer_gnutls_strerror(ret));

508

596

gnutls_deinit(*session);

509

597

return -1;

510

598

}

512

600

513

601

do {

514

602

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

515

mc.cred);

603

mc->cred);

516

604

if(quit_now){

517

605

gnutls_deinit(*session);

518

606

return -1;

519

607

}

520

608

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

521

609

if(ret != GNUTLS_E_SUCCESS){

522

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

523

safer_gnutls_strerror(ret));

610

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

611

safer_gnutls_strerror(ret));

524

612

gnutls_deinit(*session);

525

613

return -1;

526

614

}

528

616

/* ignore client certificate if any. */

529

617

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

530

618

531

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

619

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

532

620

533

621

return 0;

534

622

}

538

626

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

539

627

540

628

/* Called when a Mandos server is found */

541

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

629

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

542

630

AvahiIfIndex if_index,

543

int af){

631

int af, mandos_context *mc){

544

632

int ret, tcp_sd = -1;

545

633

ssize_t sret;

546

634

union {

571

659

pf = PF_INET;

572

660

break;

573

661

default:

574

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

662

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

575

663

errno = EINVAL;

576

664

return -1;

577

665

}

578

666

579

ret = init_gnutls_session(&session);

667

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

668

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

669

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

670

bool match = false;

671

{

672

char *interface = NULL;

673

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

674

interface))){

675

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

676

match = true;

677

break;

678

}

679

}

680

}

681

if(not match){

682

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

683

connect to the server */

684

if(debug){

685

char interface[IF_NAMESIZE];

686

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

687

perror_plus("if_indextoname");

688

} else {

689

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

690

" \"%s\"\n",

691

if_indextoname((unsigned int)if_index,

692

interface));

693

}

694

}

695

return -1;

696

}

697

}

698

699

ret = init_gnutls_session(&session, mc);

580

700

if(ret != 0){

581

701

return -1;

582

702

}

583

703

584

704

if(debug){

585

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

586

"\n", ip, port);

705

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

706

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

587

707

}

588

708

589

709

tcp_sd = socket(pf, SOCK_STREAM, 0);

590

710

if(tcp_sd < 0){

591

711

int e = errno;

592

perror("socket");

712

perror_plus("socket");

593

713

errno = e;

594

714

goto mandos_end;

595

715

}

609

729

}

610

730

if(ret < 0 ){

611

731

int e = errno;

612

perror("inet_pton");

732

perror_plus("inet_pton");

613

733

errno = e;

614

734

goto mandos_end;

615

735

}

616

736

if(ret == 0){

617

737

int e = errno;

618

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

738

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

619

739

errno = e;

620

740

goto mandos_end;

621

741

}

622

742

if(af == AF_INET6){

623

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

624

-Wconversion and

625

-Wunreachable-code */

626

743

to.in6.sin6_port = htons(port);

744

#ifdef __GNUC__

745

#pragma GCC diagnostic push

746

#pragma GCC diagnostic ignored "-Wstrict-aliasing"

747

#endif

627

748

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

628

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

629

-Wunreachable-code*/

749

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

750

#ifdef __GNUC__

751

#pragma GCC diagnostic pop

752

#endif

630

753

if(if_index == AVAHI_IF_UNSPEC){

631

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

632

" without a network interface\n");

754

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

755

" incomplete without a network interface\n");

633

756

errno = EINVAL;

634

757

goto mandos_end;

635

758

}

637

760

to.in6.sin6_scope_id = (uint32_t)if_index;

638

761

}

639

762

} else {

640

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

641

-Wconversion and

642

-Wunreachable-code */

763

to.in.sin_port = htons(port);

643

764

}

644

765

645

766

if(quit_now){

651

772

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

652

773

char interface[IF_NAMESIZE];

653

774

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

654

perror("if_indextoname");

775

perror_plus("if_indextoname");

655

776

} else {

656

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

657

ip, interface, port);

777

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

778

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

658

779

}

659

780

} else {

660

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

661

port);

781

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

782

ip, (uintmax_t)port);

662

783

}

663

784

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

664

785

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

671

792

sizeof(addrstr));

672

793

}

673

794

if(pcret == NULL){

674

perror("inet_ntop");

795

perror_plus("inet_ntop");

675

796

} else {

676

797

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

677

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

798

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

678

799

}

679

800

}

680

801

}

692

813

if(ret < 0){

693

814

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

694

815

int e = errno;

695

perror("connect");

816

perror_plus("connect");

696

817

errno = e;

697

818

}

698

819

goto mandos_end;

708

829

while(true){

709

830

size_t out_size = strlen(out);

710

831

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

711

out_size - written));

832

out_size - written));

712

833

if(ret == -1){

713

834

int e = errno;

714

perror("write");

835

perror_plus("write");

715

836

errno = e;

716

837

goto mandos_end;

717

838

}

734

855

}

735

856

736

857

if(debug){

737

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

858

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

738

859

}

739

860

740

861

if(quit_now){

742

863

goto mandos_end;

743

864

}

744

865

745

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

866

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

867

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

868

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

869

gnutls_transport_set_ptr(session,

870

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

746

871

747

872

if(quit_now){

748

873

errno = EINTR;

759

884

760

885

if(ret != GNUTLS_E_SUCCESS){

761

886

if(debug){

762

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

887

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

763

888

gnutls_perror(ret);

764

889

}

765

890

errno = EPROTO;

769

894

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

770

895

771

896

if(debug){

772

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

773

ip);

897

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

898

" %s\n", ip);

774

899

}

775

900

776

901

while(true){

781

906

}

782

907

783

908

buffer_capacity = incbuffer(&buffer, buffer_length,

784

buffer_capacity);

909

buffer_capacity);

785

910

if(buffer_capacity == 0){

786

911

int e = errno;

787

perror("incbuffer");

912

perror_plus("incbuffer");

788

913

errno = e;

789

914

goto mandos_end;

790

915

}

814

939

}

815

940

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

816

941

if(ret < 0){

817

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

942

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

943

"***\n");

818

944

gnutls_perror(ret);

819

945

errno = EPROTO;

820

946

goto mandos_end;

821

947

}

822

948

break;

823

949

default:

824

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

825

" encrypted session with Mandos server\n");

950

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

951

" encrypted session with Mandos server\n");

826

952

gnutls_bye(session, GNUTLS_SHUT_RDWR);

827

953

errno = EIO;

828

954

goto mandos_end;

833

959

}

834

960

835

961

if(debug){

836

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

962

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

837

963

}

838

964

839

965

if(quit_now){

851

977

852

978

if(buffer_length > 0){

853

979

ssize_t decrypted_buffer_size;

854

decrypted_buffer_size = pgp_packet_decrypt(buffer,

855

buffer_length,

856

&decrypted_buffer);

980

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

981

&decrypted_buffer, mc);

857

982

if(decrypted_buffer_size >= 0){

858

983

859

984

written = 0;

869

994

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

870

995

int e = errno;

871

996

if(debug){

872

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

873

strerror(errno));

997

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

998

strerror(errno));

874

999

}

875

1000

errno = e;

876

1001

goto mandos_end;

895

1020

if(e == 0){

896

1021

e = errno;

897

1022

}

898

perror("close");

1023

perror_plus("close");

899

1024

}

900

1025

gnutls_deinit(session);

1026

errno = e;

901

1027

if(quit_now){

902

e = EINTR;

1028

errno = EINTR;

903

1029

retval = -1;

904

1030

}

905

errno = e;

906

1031

}

907

1032

return retval;

908

1033

}

920

1045

AVAHI_GCC_UNUSED AvahiStringList *txt,

921

1046

AVAHI_GCC_UNUSED AvahiLookupResultFlags

922

1047

flags,

923

AVAHI_GCC_UNUSED void* userdata){

924

assert(r);

1048

void* mc){

1049

if(r == NULL){

1050

return;

1051

}

925

1052

926

1053

/* Called whenever a service has been resolved successfully or

927

1054

timed out */

933

1060

switch(event){

934

1061

default:

935

1062

case AVAHI_RESOLVER_FAILURE:

936

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

937

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

938

avahi_strerror(avahi_server_errno(mc.server)));

1063

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

1064

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

1065

domain,

1066

avahi_strerror(avahi_server_errno

1067

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

939

1068

break;

940

1069

941

1070

case AVAHI_RESOLVER_FOUND:

943

1072

char ip[AVAHI_ADDRESS_STR_MAX];

944

1073

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

945

1074

if(debug){

946

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

947

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

948

ip, (intmax_t)interface, port);

1075

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

1076

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

1077

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

949

1078

}

950

int ret = start_mandos_communication(ip, port, interface,

951

avahi_proto_to_af(proto));

1079

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

1080

interface,

1081

avahi_proto_to_af(proto),

1082

mc);

952

1083

if(ret == 0){

953

avahi_simple_poll_quit(mc.simple_poll);

1084

avahi_simple_poll_quit(simple_poll);

1085

} else {

1086

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

1087

avahi_proto_to_af(proto),

1088

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

1089

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

1090

" list\n", name);

1091

}

954

1092

}

955

1093

}

956

1094

}

966

1104

const char *domain,

967

1105

AVAHI_GCC_UNUSED AvahiLookupResultFlags

968

1106

flags,

969

AVAHI_GCC_UNUSED void* userdata){

970

assert(b);

1107

void* mc){

1108

if(b == NULL){

1109

return;

1110

}

971

1111

972

1112

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

973

1113

is removed from the LAN */

980

1120

default:

981

1121

case AVAHI_BROWSER_FAILURE:

982

1122

983

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

984

avahi_strerror(avahi_server_errno(mc.server)));

985

avahi_simple_poll_quit(mc.simple_poll);

1123

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

1124

avahi_strerror(avahi_server_errno

1125

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

1126

avahi_simple_poll_quit(simple_poll);

986

1127

return;

987

1128

988

1129

case AVAHI_BROWSER_NEW:

991

1132

the callback function is called the Avahi server will free the

992

1133

resolver for us. */

993

1134

994

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

995

name, type, domain, protocol, 0,

996

resolve_callback, NULL) == NULL)

997

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

998

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

1135

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

1136

interface, protocol, name, type,

1137

domain, protocol, 0,

1138

resolve_callback, mc) == NULL)

1139

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

1140

" %s\n", name,

1141

avahi_strerror(avahi_server_errno

1142

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

999

1143

break;

1000

1144

1001

1145

case AVAHI_BROWSER_REMOVE:

1004

1148

case AVAHI_BROWSER_ALL_FOR_NOW:

1005

1149

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1006

1150

if(debug){

1007

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

1151

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

1152

" searching...\n");

1008

1153

}

1009

1154

break;

1010

1155

}

1011

1156

}

1012

1157

1013

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

1158

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

1014

1159

static void handle_sigterm(int sig){

1015

1160

if(quit_now){

1016

1161

return;

1018

1163

quit_now = 1;

1019

1164

signal_received = sig;

1020

1165

int old_errno = errno;

1021

if(mc.simple_poll != NULL){

1022

avahi_simple_poll_quit(mc.simple_poll);

1166

/* set main loop to exit */

1167

if(simple_poll != NULL){

1168

avahi_simple_poll_quit(simple_poll);

1023

1169

}

1024

1170

errno = old_errno;

1025

1171

}

1026

1172

1173

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

1174

int ret;

1175

error_t ret_errno;

1176

1177

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

1178

if(s < 0){

1179

ret_errno = errno;

1180

perror_plus("socket");

1181

errno = ret_errno;

1182

return false;

1183

}

1184

strcpy(ifr->ifr_name, ifname);

1185

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1186

if(ret == -1){

1187

if(debug){

1188

ret_errno = errno;

1189

perror_plus("ioctl SIOCGIFFLAGS");

1190

errno = ret_errno;

1191

}

1192

return false;

1193

}

1194

return true;

1195

}

1196

1197

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

1198

1199

/* Reject the loopback device */

1200

if(ifr->ifr_flags & IFF_LOOPBACK){

1201

if(debug){

1202

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

1203

ifname);

1204

}

1205

return false;

1206

}

1207

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

1208

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

1209

if(debug){

1210

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

1211

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

1212

}

1213

return true;

1214

}

1215

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

1216

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

1217

if(debug){

1218

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1219

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

1220

}

1221

return false;

1222

}

1223

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

1224

if(ifr->ifr_flags & IFF_NOARP){

1225

if(debug){

1226

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

1227

ifname);

1228

}

1229

return false;

1230

}

1231

1232

/* Accept this device */

1233

if(debug){

1234

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

1235

}

1236

return true;

1237

}

1238

1027

1239

/*

1028

1240

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

1029

1241

* corresponds to an acceptable network device.

1030

1242

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

1031

1243

*/

1032

1244

int good_interface(const struct dirent *if_entry){

1033

ssize_t ssret;

1034

char *flagname = NULL;

1035

1245

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

1036

1246

return 0;

1037

1247

}

1038

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

1039

if_entry->d_name);

1248

1249

struct ifreq ifr;

1250

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

1251

if(debug){

1252

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

1253

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

1254

}

1255

return 0;

1256

}

1257

1258

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

1259

return 0;

1260

}

1261

return 1;

1262

}

1263

1264

/*

1265

* This function determines if a network interface is up.

1266

*/

1267

bool interface_is_up(const char *interface){

1268

struct ifreq ifr;

1269

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

1270

if(debug){

1271

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

1272

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

1273

}

1274

return false;

1275

}

1276

1277

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

1278

}

1279

1280

/*

1281

* This function determines if a network interface is running

1282

*/

1283

bool interface_is_running(const char *interface){

1284

struct ifreq ifr;

1285

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

1286

if(debug){

1287

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

1288

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

1289

}

1290

return false;

1291

}

1292

1293

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

1294

}

1295

1296

int notdotentries(const struct dirent *direntry){

1297

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

1298

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

1299

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

1300

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

1301

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

1302

return 0;

1303

}

1304

return 1;

1305

}

1306

1307

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

1308

int runnable_hook(const struct dirent *direntry){

1309

int ret;

1310

size_t sret;

1311

struct stat st;

1312

1313

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

1314

/* Empty name? */

1315

return 0;

1316

}

1317

1318

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

1319

"abcdefghijklmnopqrstuvwxyz"

1320

"0123456789"

1321

"_-");

1322

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

1323

/* Contains non-allowed characters */

1324

if(debug){

1325

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

1326

direntry->d_name);

1327

}

1328

return 0;

1329

}

1330

1331

char *fullname = NULL;

1332

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

1040

1333

if(ret < 0){

1041

perror("asprintf");

1042

return 0;

1043

}

1044

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

1045

if(flags_fd == -1){

1046

perror("open");

1047

free(flagname);

1048

return 0;

1049

}

1050

free(flagname);

1051

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

1052

/* read line from flags_fd */

1053

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

1054

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

1055

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

1056

if(flagstring == NULL){

1057

perror("malloc");

1058

close(flags_fd);

1059

return 0;

1060

}

1061

while(to_read > 0){

1062

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

1063

(size_t)to_read));

1064

if(ssret == -1){

1065

perror("read");

1066

free(flagstring);

1067

close(flags_fd);

1068

return 0;

1069

}

1070

to_read -= ssret;

1071

if(ssret == 0){

1334

perror_plus("asprintf");

1335

return 0;

1336

}

1337

1338

ret = stat(fullname, &st);

1339

if(ret == -1){

1340

if(debug){

1341

perror_plus("Could not stat hook");

1342

}

1343

return 0;

1344

}

1345

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

1346

/* Not a regular file */

1347

if(debug){

1348

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

1349

direntry->d_name);

1350

}

1351

return 0;

1352

}

1353

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

1354

/* Not executable */

1355

if(debug){

1356

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

1357

direntry->d_name);

1358

}

1359

return 0;

1360

}

1361

if(debug){

1362

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

1363

direntry->d_name);

1364

}

1365

return 1;

1366

}

1367

1368

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1369

mandos_context *mc){

1370

int ret;

1371

struct timespec now;

1372

struct timespec waited_time;

1373

intmax_t block_time;

1374

1375

while(true){

1376

if(mc->current_server == NULL){

1377

if (debug){

1378

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

1379

" No timeout!\n");

1380

}

1381

ret = avahi_simple_poll_iterate(s, -1);

1382

} else {

1383

if (debug){

1384

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

1385

" it, or wait\n");

1386

}

1387

/* the current time */

1388

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1389

if(ret == -1){

1390

perror_plus("clock_gettime");

1391

return -1;

1392

}

1393

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

1394

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

1395

waited_time.tv_sec = (now.tv_sec

1396

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

1397

waited_time.tv_nsec = (now.tv_nsec

1398

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

1399

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

1400

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

1401

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

1402

block_time = ((retry_interval

1403

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

1404

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

1405

1406

if (debug){

1407

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

1408

block_time);

1409

}

1410

1411

if(block_time <= 0){

1412

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

1413

mc->current_server->port,

1414

mc->current_server->if_index,

1415

mc->current_server->af, mc);

1416

if(ret == 0){

1417

avahi_simple_poll_quit(s);

1418

return 0;

1419

}

1420

ret = clock_gettime(CLOCK_MONOTONIC,

1421

&mc->current_server->last_seen);

1422

if(ret == -1){

1423

perror_plus("clock_gettime");

1424

return -1;

1425

}

1426

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

1427

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

1428

servers, but don't block */

1429

}

1430

1431

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

1432

}

1433

if(ret != 0){

1434

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

1435

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

1436

}

1437

}

1438

}

1439

}

1440

1441

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

1442

error_t raise_privileges(void){

1443

error_t old_errno = errno;

1444

error_t ret_errno = 0;

1445

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

1446

ret_errno = errno;

1447

perror_plus("seteuid");

1448

}

1449

errno = old_errno;

1450

return ret_errno;

1451

}

1452

1453

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

1454

error_t raise_privileges_permanently(void){

1455

error_t old_errno = errno;

1456

error_t ret_errno = raise_privileges();

1457

if(ret_errno != 0){

1458

errno = old_errno;

1459

return ret_errno;

1460

}

1461

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

1462

ret_errno = errno;

1463

perror_plus("seteuid");

1464

}

1465

errno = old_errno;

1466

return ret_errno;

1467

}

1468

1469

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

1470

error_t lower_privileges(void){

1471

error_t old_errno = errno;

1472

error_t ret_errno = 0;

1473

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

1474

ret_errno = errno;

1475

perror_plus("seteuid");

1476

}

1477

errno = old_errno;

1478

return ret_errno;

1479

}

1480

1481

/* Lower privileges permanently */

1482

error_t lower_privileges_permanently(void){

1483

error_t old_errno = errno;

1484

error_t ret_errno = 0;

1485

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

1486

ret_errno = errno;

1487

perror_plus("setuid");

1488

}

1489

errno = old_errno;

1490

return ret_errno;

1491

}

1492

1493

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

1494

const float delay){

1495

struct dirent **direntries;

1496

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

1497

alphasort);

1498

if(numhooks == -1){

1499

if(errno == ENOENT){

1500

if(debug){

1501

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

1502

" found\n", hookdir);

1503

}

1504

} else {

1505

perror_plus("scandir");

1506

}

1507

} else {

1508

struct dirent *direntry;

1509

int ret;

1510

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

1511

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

1512

direntry = direntries[i];

1513

char *fullname = NULL;

1514

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

1515

if(ret < 0){

1516

perror_plus("asprintf");

1517

continue;

1518

}

1519

if(debug){

1520

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

1521

direntry->d_name);

1522

}

1523

pid_t hook_pid = fork();

1524

if(hook_pid == 0){

1525

/* Child */

1526

/* Raise privileges */

1527

raise_privileges_permanently();

1528

/* Set group */

1529

errno = 0;

1530

ret = setgid(0);

1531

if(ret == -1){

1532

perror_plus("setgid");

1533

}

1534

/* Reset supplementary groups */

1535

errno = 0;

1536

ret = setgroups(0, NULL);

1537

if(ret == -1){

1538

perror_plus("setgroups");

1539

}

1540

dup2(devnull, STDIN_FILENO);

1541

close(devnull);

1542

dup2(STDERR_FILENO, STDOUT_FILENO);

1543

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

1544

if(ret == -1){

1545

perror_plus("setenv");

1546

_exit(EX_OSERR);

1547

}

1548

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

1549

if(ret == -1){

1550

perror_plus("setenv");

1551

_exit(EX_OSERR);

1552

}

1553

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

1554

if(ret == -1){

1555

perror_plus("setenv");

1556

_exit(EX_OSERR);

1557

}

1558

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

1559

if(ret == -1){

1560

perror_plus("setenv");

1561

_exit(EX_OSERR);

1562

}

1563

char *delaystring;

1564

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

1565

if(ret == -1){

1566

perror_plus("asprintf");

1567

_exit(EX_OSERR);

1568

}

1569

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

1570

if(ret == -1){

1571

free(delaystring);

1572

perror_plus("setenv");

1573

_exit(EX_OSERR);

1574

}

1575

free(delaystring);

1576

if(connect_to != NULL){

1577

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

1578

if(ret == -1){

1579

perror_plus("setenv");

1580

_exit(EX_OSERR);

1581

}

1582

}

1583

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

1584

perror_plus("execl");

1585

_exit(EXIT_FAILURE);

1586

}

1587

} else {

1588

int status;

1589

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

1590

perror_plus("waitpid");

1591

free(fullname);

1592

continue;

1593

}

1594

if(WIFEXITED(status)){

1595

if(WEXITSTATUS(status) != 0){

1596

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

1597

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

1598

WEXITSTATUS(status));

1599

free(fullname);

1600

continue;

1601

}

1602

} else if(WIFSIGNALED(status)){

1603

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

1604

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

1605

WTERMSIG(status));

1606

free(fullname);

1607

continue;

1608

} else {

1609

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

1610

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

1611

free(fullname);

1612

continue;

1613

}

1614

}

1615

free(fullname);

1616

if(debug){

1617

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

1618

direntry->d_name);

1619

}

1620

}

1621

close(devnull);

1622

}

1623

return true;

1624

}

1625

1626

error_t bring_up_interface(const char *const interface,

1627

const float delay){

1628

int sd = -1;

1629

error_t old_errno = errno;

1630

error_t ret_errno = 0;

1631

int ret, ret_setflags;

1632

struct ifreq network;

1633

unsigned int if_index = if_nametoindex(interface);

1634

if(if_index == 0){

1635

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

1636

errno = old_errno;

1637

return ENXIO;

1638

}

1639

1640

if(quit_now){

1641

errno = old_errno;

1642

return EINTR;

1643

}

1644

1645

if(not interface_is_up(interface)){

1646

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

1647

ret_errno = errno;

1648

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

1649

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

1650

return ret_errno;

1651

}

1652

network.ifr_flags |= IFF_UP;

1653

1654

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1655

if(sd < 0){

1656

ret_errno = errno;

1657

perror_plus("socket");

1658

errno = old_errno;

1659

return ret_errno;

1660

}

1661

1662

if(quit_now){

1663

close(sd);

1664

errno = old_errno;

1665

return EINTR;

1666

}

1667

1668

if(debug){

1669

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

1670

interface);

1671

}

1672

1673

/* Raise priviliges */

1674

raise_privileges();

1675

1676

#ifdef __linux__

1677

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1678

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

1679

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

1680

bool restore_loglevel = true;

1681

if(ret_linux == -1){

1682

restore_loglevel = false;

1683

perror_plus("klogctl");

1684

}

1685

#endif /* __linux__ */

1686

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

1687

ret_errno = errno;

1688

#ifdef __linux__

1689

if(restore_loglevel){

1690

ret_linux = klogctl(7, NULL, 0);

1691

if(ret_linux == -1){

1692

perror_plus("klogctl");

1693

}

1694

}

1695

#endif /* __linux__ */

1696

1697

/* Lower privileges */

1698

lower_privileges();

1699

1700

/* Close the socket */

1701

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

1702

if(ret == -1){

1703

perror_plus("close");

1704

}

1705

1706

if(ret_setflags == -1){

1707

errno = ret_errno;

1708

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1709

errno = old_errno;

1710

return ret_errno;

1711

}

1712

} else if(debug){

1713

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

1714

interface);

1715

}

1716

1717

/* Sleep checking until interface is running.

1718

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

1719

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

1720

if(interface_is_running(interface)){

1072

1721

break;

1073

1722

}

1074

}

1075

close(flags_fd);

1076

intmax_t tmpmax;

1077

char *tmp;

1078

errno = 0;

1079

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

1080

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

1081

and not (isspace(*tmp)))

1082

or tmpmax != (ifreq_flags)tmpmax){

1083

if(debug){

1084

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

1085

flagstring, if_entry->d_name);

1086

}

1087

free(flagstring);

1088

return 0;

1089

}

1090

free(flagstring);

1091

ifreq_flags flags = (ifreq_flags)tmpmax;

1092

/* Reject the loopback device */

1093

if(flags & IFF_LOOPBACK){

1094

if(debug){

1095

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

1096

if_entry->d_name);

1097

}

1098

return 0;

1099

}

1100

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

1101

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

1102

if(debug){

1103

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

1104

if_entry->d_name);

1105

}

1106

return 1;

1107

}

1108

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

1109

if(not (flags & IFF_BROADCAST)){

1110

if(debug){

1111

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

1112

if_entry->d_name);

1113

}

1114

return 0;

1115

}

1116

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

1117

if(flags & IFF_NOARP){

1118

if(debug){

1119

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

1120

if_entry->d_name);

1121

}

1122

return 0;

1123

}

1124

/* Accept this device */

1125

if(debug){

1126

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

1127

if_entry->d_name);

1128

}

1129

return 1;

1723

struct timespec sleeptime = { .tv_nsec = 250000000 };

1724

ret = nanosleep(&sleeptime, NULL);

1725

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

1726

perror_plus("nanosleep");

1727

}

1728

}

1729

1730

errno = old_errno;

1731

return 0;

1732

}

1733

1734

error_t take_down_interface(const char *const interface){

1735

error_t old_errno = errno;

1736

struct ifreq network;

1737

unsigned int if_index = if_nametoindex(interface);

1738

if(if_index == 0){

1739

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

1740

errno = old_errno;

1741

return ENXIO;

1742

}

1743

if(interface_is_up(interface)){

1744

error_t ret_errno = 0;

1745

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

1746

ret_errno = errno;

1747

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

1748

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

1749

return ret_errno;

1750

}

1751

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

1752

1753

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

1754

if(sd < 0){

1755

ret_errno = errno;

1756

perror_plus("socket");

1757

errno = old_errno;

1758

return ret_errno;

1759

}

1760

1761

if(debug){

1762

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

1763

interface);

1764

}

1765

1766

/* Raise priviliges */

1767

raise_privileges();

1768

1769

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

1770

ret_errno = errno;

1771

1772

/* Lower privileges */

1773

lower_privileges();

1774

1775

/* Close the socket */

1776

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

1777

if(ret == -1){

1778

perror_plus("close");

1779

}

1780

1781

if(ret_setflags == -1){

1782

errno = ret_errno;

1783

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1784

errno = old_errno;

1785

return ret_errno;

1786

}

1787

} else if(debug){

1788

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

1789

interface);

1790

}

1791

1792

errno = old_errno;

1793

return 0;

1130

1794

}

1131

1795

1132

1796

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

1797

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

1798

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

1799

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

1800

.interfaces = NULL, .interfaces_size = 0 };

1133

1801

AvahiSServiceBrowser *sb = NULL;

1134

int error;

1802

error_t ret_errno;

1135

1803

int ret;

1136

1804

intmax_t tmpmax;

1137

1805

char *tmp;

1138

1806

int exitcode = EXIT_SUCCESS;

1139

const char *interface = "";

1140

struct ifreq network;

1141

int sd = -1;

1142

bool take_down_interface = false;

1143

uid_t uid;

1144

gid_t gid;

1807

char *interfaces_to_take_down = NULL;

1808

size_t interfaces_to_take_down_size = 0;

1145

1809

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

1146

1810

bool tempdir_created = false;

1147

1811

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1148

1812

const char *seckey = PATHDIR "/" SECKEY;

1149

1813

const char *pubkey = PATHDIR "/" PUBKEY;

1814

char *interfaces_hooks = NULL;

1150

1815

1151

1816

bool gnutls_initialized = false;

1152

1817

bool gpgme_initialized = false;

1153

1818

float delay = 2.5f;

1819

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

1820

retrying the same server again */

1154

1821

1155

1822

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1156

1823

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1162

1829

errno = 0;

1163

1830

ret = setgid(gid);

1164

1831

if(ret == -1){

1165

perror("setgid");

1832

perror_plus("setgid");

1166

1833

}

1167

1834

1168

1835

/* Lower user privileges (temporarily) */

1169

1836

errno = 0;

1170

1837

ret = seteuid(uid);

1171

1838

if(ret == -1){

1172

perror("seteuid");

1839

perror_plus("seteuid");

1173

1840

}

1174

1841

1175

1842

if(quit_now){

1210

1877

.arg = "SECONDS",

1211

1878

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

1212

1879

.group = 2 },

1880

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

1881

.arg = "SECONDS",

1882

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

1883

.group = 2 },

1884

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

1885

.arg = "DIR",

1886

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

1887

.group = 2 },

1213

1888

/*

1214

1889

* These reproduce what we would get without ARGP_NO_HELP

1215

1890

*/

1233

1908

connect_to = arg;

1234

1909

break;

1235

1910

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

1236

interface = arg;

1911

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

1912

arg, (int)',');

1913

if(ret_errno != 0){

1914

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

1915

}

1237

1916

break;

1238

1917

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

1239

1918

seckey = arg;

1259

1938

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

1260

1939

argp_error(state, "Bad delay");

1261

1940

}

1941

case 132: /* --retry */

1942

errno = 0;

1943

retry_interval = strtod(arg, &tmp);

1944

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

1945

or (retry_interval * 1000) > INT_MAX

1946

or retry_interval < 0){

1947

argp_error(state, "Bad retry interval");

1948

}

1949

break;

1950

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

1951

hookdir = arg;

1262

1952

break;

1263

1953

/*

1264

1954

* These reproduce what we would get without ARGP_NO_HELP

1271

1961

argp_state_help(state, state->out_stream,

1272

1962

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1273

1963

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

1274

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

1964

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

1275

1965

exit(argp_err_exit_status);

1276

1966

break;

1277

1967

default:

1292

1982

case ENOMEM:

1293

1983

default:

1294

1984

errno = ret;

1295

perror("argp_parse");

1985

perror_plus("argp_parse");

1296

1986

exitcode = EX_OSERR;

1297

1987

goto end;

1298

1988

case EINVAL:

1300

1990

goto end;

1301

1991

}

1302

1992

}

1993

1994

{

1995

/* Work around Debian bug #633582:

1996

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

1997

1998

/* Re-raise priviliges */

1999

if(raise_privileges() == 0){

2000

struct stat st;

2001

2002

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

2003

int seckey_fd = open(seckey, O_RDONLY);

2004

if(seckey_fd == -1){

2005

perror_plus("open");

2006

} else {

2007

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

2008

if(ret == -1){

2009

perror_plus("fstat");

2010

} else {

2011

if(S_ISREG(st.st_mode)

2012

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

2013

ret = fchown(seckey_fd, uid, gid);

2014

if(ret == -1){

2015

perror_plus("fchown");

2016

}

2017

}

2018

}

2019

TEMP_FAILURE_RETRY(close(seckey_fd));

2020

}

2021

}

2022

2023

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

2024

int pubkey_fd = open(pubkey, O_RDONLY);

2025

if(pubkey_fd == -1){

2026

perror_plus("open");

2027

} else {

2028

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

2029

if(ret == -1){

2030

perror_plus("fstat");

2031

} else {

2032

if(S_ISREG(st.st_mode)

2033

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

2034

ret = fchown(pubkey_fd, uid, gid);

2035

if(ret == -1){

2036

perror_plus("fchown");

2037

}

2038

}

2039

}

2040

TEMP_FAILURE_RETRY(close(pubkey_fd));

2041

}

2042

}

2043

2044

/* Lower privileges */

2045

lower_privileges();

2046

}

2047

}

2048

2049

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

2050

{

2051

char *interface = NULL;

2052

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

2053

interface))){

2054

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

2055

and if_nametoindex(interface) == 0){

2056

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

2057

fprintf_plus(stderr, "Not using nonexisting interface"

2058

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

2059

}

2060

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

2061

interface = NULL;

2062

}

2063

}

2064

}

2065

2066

/* Run network hooks */

2067

{

2068

if(mc.interfaces != NULL){

2069

interfaces_hooks = malloc(mc.interfaces_size);

2070

if(interfaces_hooks == NULL){

2071

perror_plus("malloc");

2072

goto end;

2073

}

2074

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

2075

argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');

2076

}

2077

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

2078

interfaces_hooks : "", delay)){

2079

goto end;

2080

}

2081

}

1303

2082

1304

2083

if(not debug){

1305

2084

avahi_set_log_function(empty_log);

1306

2085

}

1307

1308

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

1309

struct dirent **direntries;

1310

ret = scandir(sys_class_net, &direntries, good_interface,

1311

alphasort);

1312

if(ret >= 1){

1313

/* Pick the first good interface */

1314

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

1315

if(debug){

1316

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

1317

}

1318

if(interface == NULL){

1319

perror("malloc");

1320

free(direntries);

1321

exitcode = EXIT_FAILURE;

1322

goto end;

1323

}

1324

free(direntries);

1325

} else {

1326

free(direntries);

1327

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

1328

exitcode = EXIT_FAILURE;

1329

goto end;

1330

}

1331

}

1332

2086

1333

2087

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

1334

2088

from the signal handler */

1335

2089

/* Initialize the pseudo-RNG for Avahi */

1336

2090

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

1337

mc.simple_poll = avahi_simple_poll_new();

1338

if(mc.simple_poll == NULL){

1339

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");

1340

2095

exitcode = EX_UNAVAILABLE;

1341

2096

goto end;

1342

2097

}

1344

2099

sigemptyset(&sigterm_action.sa_mask);

1345

2100

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

1346

2101

if(ret == -1){

1347

perror("sigaddset");

2102

perror_plus("sigaddset");

1348

2103

exitcode = EX_OSERR;

1349

2104

goto end;

1350

2105

}

1351

2106

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

1352

2107

if(ret == -1){

1353

perror("sigaddset");

2108

perror_plus("sigaddset");

1354

2109

exitcode = EX_OSERR;

1355

2110

goto end;

1356

2111

}

1357

2112

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

1358

2113

if(ret == -1){

1359

perror("sigaddset");

2114

perror_plus("sigaddset");

1360

2115

exitcode = EX_OSERR;

1361

2116

goto end;

1362

2117

}

1366

2121

*/

1367

2122

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

1368

2123

if(ret == -1){

1369

perror("sigaction");

2124

perror_plus("sigaction");

1370

2125

return EX_OSERR;

1371

2126

}

1372

2127

if(old_sigterm_action.sa_handler != SIG_IGN){

1373

2128

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

1374

2129

if(ret == -1){

1375

perror("sigaction");

2130

perror_plus("sigaction");

1376

2131

exitcode = EX_OSERR;

1377

2132

goto end;

1378

2133

}

1379

2134

}

1380

2135

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

1381

2136

if(ret == -1){

1382

perror("sigaction");

2137

perror_plus("sigaction");

1383

2138

return EX_OSERR;

1384

2139

}

1385

2140

if(old_sigterm_action.sa_handler != SIG_IGN){

1386

2141

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

1387

2142

if(ret == -1){

1388

perror("sigaction");

2143

perror_plus("sigaction");

1389

2144

exitcode = EX_OSERR;

1390

2145

goto end;

1391

2146

}

1392

2147

}

1393

2148

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

1394

2149

if(ret == -1){

1395

perror("sigaction");

2150

perror_plus("sigaction");

1396

2151

return EX_OSERR;

1397

2152

}

1398

2153

if(old_sigterm_action.sa_handler != SIG_IGN){

1399

2154

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

1400

2155

if(ret == -1){

1401

perror("sigaction");

1402

exitcode = EX_OSERR;

1403

goto end;

1404

}

1405

}

1406

1407

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

1408

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

1409

if_index = (AvahiIfIndex) if_nametoindex(interface);

1410

if(if_index == 0){

1411

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

1412

exitcode = EX_UNAVAILABLE;

1413

goto end;

1414

}

1415

1416

if(quit_now){

1417

goto end;

1418

}

1419

1420

/* Re-raise priviliges */

1421

errno = 0;

1422

ret = seteuid(0);

1423

if(ret == -1){

1424

perror("seteuid");

1425

}

1426

1427

#ifdef __linux__

1428

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1429

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

1430

ret = klogctl(8, NULL, 5);

1431

bool restore_loglevel = true;

1432

if(ret == -1){

1433

restore_loglevel = false;

1434

perror("klogctl");

1435

}

1436

#endif /* __linux__ */

1437

1438

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1439

if(sd < 0){

1440

perror("socket");

1441

exitcode = EX_OSERR;

1442

#ifdef __linux__

1443

if(restore_loglevel){

1444

ret = klogctl(7, NULL, 0);

1445

if(ret == -1){

1446

perror("klogctl");

1447

}

1448

}

1449

#endif /* __linux__ */

1450

/* Lower privileges */

1451

errno = 0;

1452

ret = seteuid(uid);

1453

if(ret == -1){

1454

perror("seteuid");

1455

}

1456

goto end;

1457

}

1458

strcpy(network.ifr_name, interface);

1459

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

1460

if(ret == -1){

1461

perror("ioctl SIOCGIFFLAGS");

1462

#ifdef __linux__

1463

if(restore_loglevel){

1464

ret = klogctl(7, NULL, 0);

1465

if(ret == -1){

1466

perror("klogctl");

1467

}

1468

}

1469

#endif /* __linux__ */

1470

exitcode = EX_OSERR;

1471

/* Lower privileges */

1472

errno = 0;

1473

ret = seteuid(uid);

1474

if(ret == -1){

1475

perror("seteuid");

1476

}

1477

goto end;

1478

}

1479

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

1480

network.ifr_flags |= IFF_UP;

1481

take_down_interface = true;

1482

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

1483

if(ret == -1){

1484

take_down_interface = false;

1485

perror("ioctl SIOCSIFFLAGS +IFF_UP");

1486

exitcode = EX_OSERR;

1487

#ifdef __linux__

1488

if(restore_loglevel){

1489

ret = klogctl(7, NULL, 0);

1490

if(ret == -1){

1491

perror("klogctl");

2156

perror_plus("sigaction");

2157

exitcode = EX_OSERR;

2158

goto end;

2159

}

2160

}

2161

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

errno = ret_errno;

2175

perror_plus("argz_add");

2176

continue;

2177

}

2178

if(debug){

2179

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

2180

direntries[i]->d_name);

2181

}

2182

}

2183

free(direntries);

2184

} else {

2185

free(direntries);

2186

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

2187

exitcode = EXIT_FAILURE;

2188

goto end;

2189

}

2190

}

2191

2192

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

2193

{

2194

char *interface = NULL;

2195

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

2196

interface))){

2197

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

2198

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

2199

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

2200

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

2201

interface);

2202

interface = NULL;

2203

while((interface = argz_next(mc.interfaces,

2204

mc.interfaces_size, interface))){

2205

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

2206

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

2207

interface);

2208

interface = NULL;

1492

2209

}

1493

2210

}

1494

#endif /* __linux__ */

1495

/* Lower privileges */

1496

errno = 0;

1497

ret = seteuid(uid);

1498

if(ret == -1){

1499

perror("seteuid");

1500

}

1501

goto end;

1502

}

1503

}

1504

/* sleep checking until interface is running */

1505

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

1506

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

1507

if(ret == -1){

1508

perror("ioctl SIOCGIFFLAGS");

1509

} else if(network.ifr_flags & IFF_RUNNING){

1510

2211

break;

1511

2212

}

1512

struct timespec sleeptime = { .tv_nsec = 250000000 };

1513

ret = nanosleep(&sleeptime, NULL);

1514

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

1515

perror("nanosleep");

1516

}

1517

}

1518

if(not take_down_interface){

1519

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

1520

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

1521

if(ret == -1){

1522

perror("close");

1523

}

1524

}

1525

#ifdef __linux__

1526

if(restore_loglevel){

1527

/* Restores kernel loglevel to default */

1528

ret = klogctl(7, NULL, 0);

1529

if(ret == -1){

1530

perror("klogctl");

1531

}

1532

}

1533

#endif /* __linux__ */

1534

/* Lower privileges */

1535

errno = 0;

1536

if(take_down_interface){

1537

/* Lower privileges */

1538

ret = seteuid(uid);

1539

if(ret == -1){

1540

perror("seteuid");

1541

}

1542

} else {

1543

/* Lower privileges permanently */

1544

ret = setuid(uid);

1545

if(ret == -1){

1546

perror("setuid");

1547

}

1548

}

2213

bool interface_was_up = interface_is_up(interface);

2214

ret = bring_up_interface(interface, delay);

2215

if(not interface_was_up){

2216

if(ret != 0){

2217

errno = ret;

2218

perror_plus("Failed to bring up interface");

2219

} else {

2220

ret_errno = argz_add(&interfaces_to_take_down,

2221

&interfaces_to_take_down_size,

2222

interface);

2223

if(ret_errno != 0){

2224

errno = ret_errno;

2225

perror_plus("argz_add");

2226

}

2227

}

2228

}

2229

}

2230

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

2231

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

2232

}

2233

}

2234

2235

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

2236

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

2237

if(debug){

2238

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

2239

mc.interfaces);

2240

}

2241

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

1549

2242

}

1550

2243

1551

2244

if(quit_now){

1552

2245

goto end;

1553

2246

}

1554

2247

1555

ret = init_gnutls_global(pubkey, seckey);

2248

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

1556

2249

if(ret == -1){

1557

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

2250

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

1558

2251

exitcode = EX_UNAVAILABLE;

1559

2252

goto end;

1560

2253

} else {

1565

2258

goto end;

1566

2259

}

1567

2260

2261

if(mkdtemp(tempdir) == NULL){

2262

perror_plus("mkdtemp");

2263

goto end;

2264

}

1568

2265

tempdir_created = true;

1569

if(mkdtemp(tempdir) == NULL){

1570

tempdir_created = false;

1571

perror("mkdtemp");

1572

goto end;

1573

}

1574

2266

1575

2267

if(quit_now){

1576

2268

goto end;

1577

2269

}

1578

2270

1579

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

1580

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

2271

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

2272

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

1581

2273

exitcode = EX_UNAVAILABLE;

1582

2274

goto end;

1583

2275

} else {

1592

2284

/* Connect directly, do not use Zeroconf */

1593

2285

/* (Mainly meant for debugging) */

1594

2286

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

2287

1595

2288

if(address == NULL){

1596

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

2289

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

1597

2290

exitcode = EX_USAGE;

1598

2291

goto end;

1599

2292

}

1602

2295

goto end;

1603

2296

}

1604

2297

1605

uint16_t port;

2298

in_port_t port;

1606

2299

errno = 0;

1607

2300

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

1608

2301

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

1609

or tmpmax != (uint16_t)tmpmax){

1610

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

2302

or tmpmax != (in_port_t)tmpmax){

2303

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

1611

2304

exitcode = EX_USAGE;

1612

2305

goto end;

1613

2306

}

1614

2307

1615

2308

if(quit_now){

1616

2309

goto end;

1617

2310

}

1618

2311

1619

port = (uint16_t)tmpmax;

2312

port = (in_port_t)tmpmax;

1620

2313

*address = '\0';

1621

address = connect_to;

1622

2314

/* Colon in address indicates IPv6 */

1623

2315

int af;

1624

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

2316

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

1625

2317

af = AF_INET6;

2318

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

2319

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

2320

{

2321

connect_to++;

2322

address[-1] = '\0';

2323

}

1626

2324

} else {

1627

2325

af = AF_INET;

1628

2326

}

2327

address = connect_to;

1629

2328

1630

2329

if(quit_now){

1631

2330

goto end;

1632

2331

}

1633

2332

1634

2333

while(not quit_now){

1635

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

2334

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

2335

&mc);

1636

2336

if(quit_now or ret == 0){

1637

2337

break;

1638

2338

}

1639

sleep(15);

1640

};

1641

2339

if(debug){

2340

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

2341

(int)retry_interval);

2342

}

2343

sleep((unsigned int)retry_interval);

2344

}

2345

1642

2346

if (not quit_now){

1643

2347

exitcode = EXIT_SUCCESS;

1644

2348

}

1645

2349

1646

2350

goto end;

1647

2351

}

1648

2352

1660

2364

config.publish_domain = 0;

1661

2365

1662

2366

/* Allocate a new server */

1663

mc.server = avahi_server_new(avahi_simple_poll_get

1664

(mc.simple_poll), &config, NULL,

1665

NULL, &error);

2367

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2368

&config, NULL, NULL, &ret_errno);

1666

2369

1667

2370

/* Free the Avahi configuration data */

1668

2371

avahi_server_config_free(&config);

1670

2373

1671

2374

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

1672

2375

if(mc.server == NULL){

1673

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

1674

avahi_strerror(error));

2376

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

2377

avahi_strerror(ret_errno));

1675

2378

exitcode = EX_UNAVAILABLE;

1676

2379

goto end;

1677

2380

}

1683

2386

/* Create the Avahi service browser */

1684

2387

sb = avahi_s_service_browser_new(mc.server, if_index,

1685

2388

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1686

NULL, 0, browse_callback, NULL);

2389

NULL, 0, browse_callback,

2390

(void *)&mc);

1687

2391

if(sb == NULL){

1688

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

1689

avahi_strerror(avahi_server_errno(mc.server)));

2392

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

2393

avahi_strerror(avahi_server_errno(mc.server)));

1690

2394

exitcode = EX_UNAVAILABLE;

1691

2395

goto end;

1692

2396

}

1698

2402

/* Run the main loop */

1699

2403

1700

2404

if(debug){

1701

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

1702

}

1703

1704

avahi_simple_poll_loop(mc.simple_poll);

2405

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

2406

}

2407

2408

ret = avahi_loop_with_timeout(simple_poll,

2409

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

2410

if(debug){

2411

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

2412

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

2413

}

1705

2414

1706

2415

end:

1707

2416

1708

2417

if(debug){

1709

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

2418

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

1710

2419

}

1711

2420

1712

2421

/* Cleanup things */

2422

free(mc.interfaces);

2423

1713

2424

if(sb != NULL)

1714

2425

avahi_s_service_browser_free(sb);

1715

2426

1716

2427

if(mc.server != NULL)

1717

2428

avahi_server_free(mc.server);

1718

2429

1719

if(mc.simple_poll != NULL)

1720

avahi_simple_poll_free(mc.simple_poll);

2430

if(simple_poll != NULL)

2431

avahi_simple_poll_free(simple_poll);

1721

2432

1722

2433

if(gnutls_initialized){

1723

2434

gnutls_certificate_free_credentials(mc.cred);

1729

2440

gpgme_release(mc.ctx);

1730

2441

}

1731

2442

1732

/* Take down the network interface */

1733

if(take_down_interface){

1734

/* Re-raise priviliges */

1735

errno = 0;

1736

ret = seteuid(0);

1737

if(ret == -1){

1738

perror("seteuid");

2443

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

2444

has seen */

2445

if(mc.current_server != NULL){

2446

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

2447

while(mc.current_server != NULL){

2448

server *next = mc.current_server->next;

2449

free(mc.current_server);

2450

mc.current_server = next;

1739

2451

}

1740

if(geteuid() == 0){

1741

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

1742

if(ret == -1){

1743

perror("ioctl SIOCGIFFLAGS");

1744

} else if(network.ifr_flags & IFF_UP) {

1745

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

1746

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

1747

if(ret == -1){

1748

perror("ioctl SIOCSIFFLAGS -IFF_UP");

2452

}

2453

2454

/* Re-raise priviliges */

2455

{

2456

raise_privileges();

2457

2458

/* Run network hooks */

2459

run_network_hooks("stop", interfaces_hooks != NULL ?

2460

interfaces_hooks : "", delay);

2461

2462

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

2463

{

2464

char *interface = NULL;

2465

while((interface=argz_next(interfaces_to_take_down,

2466

interfaces_to_take_down_size,

2467

interface))){

2468

ret_errno = take_down_interface(interface);

2469

if(ret_errno != 0){

2470

errno = ret_errno;

2471

perror_plus("Failed to take down interface");

1749

2472

}

1750

2473

}

1751

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

1752

if(ret == -1){

1753

perror("close");

1754

}

1755

/* Lower privileges permanently */

1756

errno = 0;

1757

ret = setuid(uid);

1758

if(ret == -1){

1759

perror("setuid");

2474

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

2475

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

2476

" down\n");

1760

2477

}

1761

2478

}

2479

2480

lower_privileges_permanently();

1762

2481

}

1763

2482

1764

/* Removes the temp directory used by GPGME */

2483

free(interfaces_to_take_down);

2484

free(interfaces_hooks);

2485

2486

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

1765

2487

if(tempdir_created){

1766

DIR *d;

1767

struct dirent *direntry;

1768

d = opendir(tempdir);

1769

if(d == NULL){

1770

if(errno != ENOENT){

1771

perror("opendir");

1772

}

1773

} else {

1774

while(true){

1775

direntry = readdir(d);

1776

if(direntry == NULL){

1777

break;

1778

}

1779

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

1780

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

1781

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

1782

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

1783

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

1784

continue;

1785

}

2488

struct dirent **direntries = NULL;

2489

struct dirent *direntry = NULL;

2490

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

2491

alphasort);

2492

if (numentries > 0){

2493

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

2494

direntry = direntries[i];

1786

2495

char *fullname = NULL;

1787

2496

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

1788

2497

direntry->d_name);

1789

2498

if(ret < 0){

1790

perror("asprintf");

2499

perror_plus("asprintf");

1791

2500

continue;

1792

2501

}

1793

2502

ret = remove(fullname);

1794

2503

if(ret == -1){

1795

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

1796

strerror(errno));

2504

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

2505

strerror(errno));

1797

2506

}

1798

2507

free(fullname);

1799

2508

}

1800

closedir(d);

2509

}

2510

2511

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

2512

free(direntries);

2513

if (numentries == -1){

2514

perror_plus("scandir");

1801

2515

}

1802

2516

ret = rmdir(tempdir);

1803

2517

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

1804

perror("rmdir");

2518

perror_plus("rmdir");

1805

2519

}

1806

2520

}

1807

2521

1812

2526

&old_sigterm_action,

1813

2527

NULL));

1814

2528

if(ret == -1){

1815

perror("sigaction");

2529

perror_plus("sigaction");

1816

2530

}

1817

2531

do {

1818

2532

ret = raise(signal_received);

1819

2533

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

1820

2534

if(ret != 0){

1821

perror("raise");

2535

perror_plus("raise");

1822

2536

abort();

1823

2537

}

1824

2538

TEMP_FAILURE_RETRY(pause());