/mandos/trunk : revision 579

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

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*

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* Everything else is

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*

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

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

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* along with this program. If not, see

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

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*

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

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

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*/

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

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#ifndef _LARGEFILE_SOURCE

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#define _LARGEFILE_SOURCE

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#endif

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#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

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#endif

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

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

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stdout, ferror(), sscanf(),

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remove() */

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stdout, ferror(), remove() */

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

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

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

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srand() */

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

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strtof(), abort() */

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

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

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

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sockaddr_in6, PF_INET6,

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SOCK_STREAM, uid_t, gid_t, open(),

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opendir(), DIR */

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

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

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

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inet_pton(), connect() */

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

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

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*/

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

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

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strtoimax() */

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

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

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

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

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program_invocation_short_name */

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

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

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SIOCSIFFLAGS, if_indextoname(),

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if_nametoindex(), IF_NAMESIZE */

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INET_ADDRSTRLEN, INET6_ADDRSTRLEN

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*/

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

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

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setgid() */

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

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

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

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

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

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

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argp_state, struct argp,

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argp_parse(), ARGP_KEY_ARG,

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ARGP_KEY_END, ARGP_ERR_UNKNOWN */

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

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

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sigaction(), SIGTERM, sig_atomic_t,

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raise() */

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

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EX_NOHOST, EX_IOERR, EX_PROTOCOL */

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

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WEXITSTATUS(), WTERMSIG() */

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

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#ifdef __linux__

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

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#endif

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#endif /* __linux__ */

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/* Avahi */

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/* All Avahi types, constants and functions

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111

init_gnutls_session(),

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112

GNUTLS_* */

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113

#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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126

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

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127

#define SECKEY "seckey.txt"

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#define PUBKEY "pubkey.txt"

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

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bool debug = false;

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static const char mandos_protocol_version[] = "1";

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

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

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

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

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char *connect_to = NULL;

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const char *hookdir = HOOKDIR;

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

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typedef struct server{

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const char *ip;

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uint16_t port;

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AvahiIfIndex if_index;

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int af;

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struct timespec last_seen;

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struct server *next;

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struct server *prev;

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} server;

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

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typedef struct {

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156

gnutls_dh_params_t dh_params;

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const char *priority;

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gpgme_ctx_t ctx;

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server *current_server;

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160

} mandos_context;

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161

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

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mandos_context mc;

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

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.dh_bits = 1024, .priority = "SECURE256"

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

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.current_server = NULL };

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168

sig_atomic_t quit_now = 0;

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int signal_received = 0;

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/* Function to use when printing errors */

172

void perror_plus(const char *print_text){

173

int e = errno;

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

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program_invocation_short_name);

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errno = e;

177

perror(print_text);

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}

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

181

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

182

va_list ap;

183

va_start (ap, format);

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

186

program_invocation_short_name));

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

188

}

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189

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/*

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

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* additional bytes. "buffer_capacity" is how much is currently

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* allocated, "buffer_length" is how much is already used.

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

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

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* "buffer_length" is how much is already used.

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194

*/

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size_t incbuffer(char **buffer, size_t buffer_length,

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size_t buffer_capacity){

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size_t buffer_capacity){

143

197

if(buffer_length + BUFFER_SIZE > buffer_capacity){

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198

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

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199

if(buffer == NULL){

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return buffer_capacity;

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205

}

152

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

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

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int af){

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int ret;

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

212

if(new_server == NULL){

213

perror_plus("malloc");

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return false;

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}

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

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.port = port,

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.if_index = if_index,

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.af = af };

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if(new_server->ip == NULL){

221

perror_plus("strdup");

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return false;

223

}

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/* Special case of first server */

225

if (mc.current_server == NULL){

226

new_server->next = new_server;

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new_server->prev = new_server;

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mc.current_server = new_server;

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

230

} else {

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new_server->next = mc.current_server;

232

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

233

new_server->prev->next = new_server;

234

mc.current_server->prev = new_server;

235

}

236

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

237

if(ret == -1){

238

perror_plus("clock_gettime");

239

return false;

240

}

241

return true;

242

}

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/*

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* Initialize GPGME.

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246

*/

156

static bool init_gpgme(const char *seckey,

157

const char *pubkey, const char *tempdir){

158

int ret;

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

248

const char *tempdir){

159

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gpgme_error_t rc;

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250

gpgme_engine_info_t engine_info;

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251

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

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255

*/

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bool import_key(const char *filename){

257

int ret;

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int fd;

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gpgme_data_t pgp_data;

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

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if(fd == -1){

172

perror("open");

263

perror_plus("open");

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return false;

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265

}

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rc = gpgme_data_new_from_fd(&pgp_data, fd);

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if(rc != GPG_ERR_NO_ERROR){

178

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

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}

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rc = gpgme_op_import(mc.ctx, pgp_data);

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if(rc != GPG_ERR_NO_ERROR){

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

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}

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

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if(ret == -1){

192

perror("close");

283

perror_plus("close");

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}

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gpgme_data_release(pgp_data);

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return true;

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}

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if(debug){

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fprintf(stderr, "Initialize 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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if(rc != GPG_ERR_NO_ERROR){

206

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

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gpgme_strsource(rc), gpgme_strerror(rc));

297

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

298

gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

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300

}

210

301

211

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

302

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

212

303

rc = gpgme_get_engine_info(&engine_info);

213

304

if(rc != GPG_ERR_NO_ERROR){

214

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

215

gpgme_strsource(rc), gpgme_strerror(rc));

305

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

306

gpgme_strsource(rc), gpgme_strerror(rc));

216

307

return false;

217

308

}

218

309

while(engine_info != NULL){

224

315

engine_info = engine_info->next;

225

316

}

226

317

if(engine_info == NULL){

227

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

318

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

319

tempdir);

228

320

return false;

229

321

}

230

322

231

323

/* Create new GPGME "context" */

232

324

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

233

325

if(rc != GPG_ERR_NO_ERROR){

234

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

235

gpgme_strsource(rc), gpgme_strerror(rc));

326

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

327

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

328

gpgme_strerror(rc));

236

329

return false;

237

330

}

238

331

240

333

return false;

241

334

}

242

335

243

return true;

336

return true;

244

337

}

245

338

246

339

/*

257

350

ssize_t plaintext_length = 0;

258

351

259

352

if(debug){

260

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

353

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

261

354

}

262

355

263

356

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

264

357

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

265

358

0);

266

359

if(rc != GPG_ERR_NO_ERROR){

267

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

268

gpgme_strsource(rc), gpgme_strerror(rc));

360

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

361

gpgme_strsource(rc), gpgme_strerror(rc));

269

362

return -1;

270

363

}

271

364

272

365

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

273

366

rc = gpgme_data_new(&dh_plain);

274

367

if(rc != GPG_ERR_NO_ERROR){

275

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

276

gpgme_strsource(rc), gpgme_strerror(rc));

368

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

369

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

370

gpgme_strsource(rc), gpgme_strerror(rc));

277

371

gpgme_data_release(dh_crypto);

278

372

return -1;

279

373

}

282

376

data buffer */

283

377

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

284

378

if(rc != GPG_ERR_NO_ERROR){

285

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

286

gpgme_strsource(rc), gpgme_strerror(rc));

379

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

380

gpgme_strsource(rc), gpgme_strerror(rc));

287

381

plaintext_length = -1;

288

382

if(debug){

289

383

gpgme_decrypt_result_t result;

290

384

result = gpgme_op_decrypt_result(mc.ctx);

291

385

if(result == NULL){

292

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

386

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

293

387

} else {

294

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

295

result->unsupported_algorithm);

296

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

297

result->wrong_key_usage);

388

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

389

result->unsupported_algorithm);

390

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

391

result->wrong_key_usage);

298

392

if(result->file_name != NULL){

299

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

393

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

300

394

}

301

395

gpgme_recipient_t recipient;

302

396

recipient = result->recipients;

303

if(recipient){

304

while(recipient != NULL){

305

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

306

gpgme_pubkey_algo_name(recipient->pubkey_algo));

307

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

308

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

309

recipient->status == GPG_ERR_NO_SECKEY

310

? "No" : "Yes");

311

recipient = recipient->next;

312

}

397

while(recipient != NULL){

398

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

399

gpgme_pubkey_algo_name

400

(recipient->pubkey_algo));

401

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

402

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

403

recipient->status == GPG_ERR_NO_SECKEY

404

? "No" : "Yes");

405

recipient = recipient->next;

313

406

}

314

407

}

315

408

}

317

410

}

318

411

319

412

if(debug){

320

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

413

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

321

414

}

322

415

323

416

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

324

417

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

325

perror("gpgme_data_seek");

418

perror_plus("gpgme_data_seek");

326

419

plaintext_length = -1;

327

420

goto decrypt_end;

328

421

}

330

423

*plaintext = NULL;

331

424

while(true){

332

425

plaintext_capacity = incbuffer(plaintext,

333

(size_t)plaintext_length,

334

plaintext_capacity);

426

(size_t)plaintext_length,

427

plaintext_capacity);

335

428

if(plaintext_capacity == 0){

336

perror("incbuffer");

337

plaintext_length = -1;

338

goto decrypt_end;

429

perror_plus("incbuffer");

430

plaintext_length = -1;

431

goto decrypt_end;

339

432

}

340

433

341

434

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

346

439

break;

347

440

}

348

441

if(ret < 0){

349

perror("gpgme_data_read");

442

perror_plus("gpgme_data_read");

350

443

plaintext_length = -1;

351

444

goto decrypt_end;

352

445

}

354

447

}

355

448

356

449

if(debug){

357

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

450

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

358

451

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

359

452

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

360

453

}

382

475

/* GnuTLS log function callback */

383

476

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

384

477

const char* string){

385

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

478

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

386

479

}

387

480

388

481

static int init_gnutls_global(const char *pubkeyfilename,

390

483

int ret;

391

484

392

485

if(debug){

393

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

486

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

394

487

}

395

488

396

489

ret = gnutls_global_init();

397

490

if(ret != GNUTLS_E_SUCCESS){

398

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

399

safer_gnutls_strerror(ret));

491

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

492

safer_gnutls_strerror(ret));

400

493

return -1;

401

494

}

402

495

409

502

}

410

503

411

504

/* OpenPGP credentials */

412

gnutls_certificate_allocate_credentials(&mc.cred);

505

ret = gnutls_certificate_allocate_credentials(&mc.cred);

413

506

if(ret != GNUTLS_E_SUCCESS){

414

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

415

from

416

-Wunreachable-code

417

*/

418

safer_gnutls_strerror(ret));

507

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

508

safer_gnutls_strerror(ret));

419

509

gnutls_global_deinit();

420

510

return -1;

421

511

}

422

512

423

513

if(debug){

424

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

425

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

426

seckeyfilename);

514

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

515

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

516

pubkeyfilename,

517

seckeyfilename);

427

518

}

428

519

429

520

ret = gnutls_certificate_set_openpgp_key_file

430

521

(mc.cred, pubkeyfilename, seckeyfilename,

431

522

GNUTLS_OPENPGP_FMT_BASE64);

432

523

if(ret != GNUTLS_E_SUCCESS){

433

fprintf(stderr,

434

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

435

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

436

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

437

safer_gnutls_strerror(ret));

524

fprintf_plus(stderr,

525

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

526

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

527

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

528

safer_gnutls_strerror(ret));

438

529

goto globalfail;

439

530

}

440

531

441

532

/* GnuTLS server initialization */

442

533

ret = gnutls_dh_params_init(&mc.dh_params);

443

534

if(ret != GNUTLS_E_SUCCESS){

444

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

445

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

535

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

536

" initialization: %s\n",

537

safer_gnutls_strerror(ret));

446

538

goto globalfail;

447

539

}

448

540

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

449

541

if(ret != GNUTLS_E_SUCCESS){

450

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

451

safer_gnutls_strerror(ret));

542

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

543

safer_gnutls_strerror(ret));

452

544

goto globalfail;

453

545

}

454

546

467

559

static int init_gnutls_session(gnutls_session_t *session){

468

560

int ret;

469

561

/* GnuTLS session creation */

470

ret = gnutls_init(session, GNUTLS_SERVER);

562

do {

563

ret = gnutls_init(session, GNUTLS_SERVER);

564

if(quit_now){

565

return -1;

566

}

567

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

471

568

if(ret != GNUTLS_E_SUCCESS){

472

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

473

safer_gnutls_strerror(ret));

569

fprintf_plus(stderr,

570

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

571

safer_gnutls_strerror(ret));

474

572

}

475

573

476

574

{

477

575

const char *err;

478

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

576

do {

577

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

578

if(quit_now){

579

gnutls_deinit(*session);

580

return -1;

581

}

582

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

479

583

if(ret != GNUTLS_E_SUCCESS){

480

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

481

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

482

safer_gnutls_strerror(ret));

584

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

585

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

586

safer_gnutls_strerror(ret));

483

587

gnutls_deinit(*session);

484

588

return -1;

485

589

}

486

590

}

487

591

488

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

489

mc.cred);

592

do {

593

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

594

mc.cred);

595

if(quit_now){

596

gnutls_deinit(*session);

597

return -1;

598

}

599

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

490

600

if(ret != GNUTLS_E_SUCCESS){

491

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

492

safer_gnutls_strerror(ret));

601

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

602

safer_gnutls_strerror(ret));

493

603

gnutls_deinit(*session);

494

604

return -1;

495

605

}

496

606

497

607

/* ignore client certificate if any. */

498

gnutls_certificate_server_set_request(*session,

499

GNUTLS_CERT_IGNORE);

608

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

500

609

501

610

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

502

611

511

620

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

512

621

AvahiIfIndex if_index,

513

622

int af){

514

int ret, tcp_sd;

623

int ret, tcp_sd = -1;

515

624

ssize_t sret;

516

625

union {

517

626

struct sockaddr_in in;

518

627

struct sockaddr_in6 in6;

519

628

} to;

520

629

char *buffer = NULL;

521

char *decrypted_buffer;

630

char *decrypted_buffer = NULL;

522

631

size_t buffer_length = 0;

523

632

size_t buffer_capacity = 0;

524

ssize_t decrypted_buffer_size;

525

633

size_t written;

526

int retval = 0;

634

int retval = -1;

527

635

gnutls_session_t session;

528

636

int pf; /* Protocol family */

529

637

638

errno = 0;

639

640

if(quit_now){

641

errno = EINTR;

642

return -1;

643

}

644

530

645

switch(af){

531

646

case AF_INET6:

532

647

pf = PF_INET6;

535

650

pf = PF_INET;

536

651

break;

537

652

default:

538

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

653

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

654

errno = EINVAL;

539

655

return -1;

540

656

}

541

657

545

661

}

546

662

547

663

if(debug){

548

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

549

"\n", ip, port);

664

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

665

PRIu16 "\n", ip, port);

550

666

}

551

667

552

668

tcp_sd = socket(pf, SOCK_STREAM, 0);

553

669

if(tcp_sd < 0){

554

perror("socket");

555

return -1;

670

int e = errno;

671

perror_plus("socket");

672

errno = e;

673

goto mandos_end;

674

}

675

676

if(quit_now){

677

errno = EINTR;

678

goto mandos_end;

556

679

}

557

680

558

681

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

559

682

if(af == AF_INET6){

560

to.in6.sin6_family = (uint16_t)af;

683

to.in6.sin6_family = (sa_family_t)af;

561

684

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

562

685

} else { /* IPv4 */

563

686

to.in.sin_family = (sa_family_t)af;

564

687

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

565

688

}

566

689

if(ret < 0 ){

567

perror("inet_pton");

568

return -1;

690

int e = errno;

691

perror_plus("inet_pton");

692

errno = e;

693

goto mandos_end;

569

694

}

570

695

if(ret == 0){

571

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

572

return -1;

696

int e = errno;

697

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

698

errno = e;

699

goto mandos_end;

573

700

}

574

701

if(af == AF_INET6){

575

702

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

578

705

579

706

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

580

707

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

581

-Wunreachable-code*/

708

-Wunreachable-code*/

582

709

if(if_index == AVAHI_IF_UNSPEC){

583

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

584

" without a network interface\n");

585

return -1;

710

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

711

" incomplete without a network interface\n");

712

errno = EINVAL;

713

goto mandos_end;

586

714

}

587

715

/* Set the network interface number as scope */

588

716

to.in6.sin6_scope_id = (uint32_t)if_index;

593

721

-Wunreachable-code */

594

722

}

595

723

724

if(quit_now){

725

errno = EINTR;

726

goto mandos_end;

727

}

728

596

729

if(debug){

597

730

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

598

731

char interface[IF_NAMESIZE];

599

732

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

600

perror("if_indextoname");

733

perror_plus("if_indextoname");

601

734

} else {

602

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

603

ip, interface, port);

735

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

736

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

604

737

}

605

738

} else {

606

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

607

port);

739

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

740

ip, port);

608

741

}

609

742

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

610

743

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

617

750

sizeof(addrstr));

618

751

}

619

752

if(pcret == NULL){

620

perror("inet_ntop");

753

perror_plus("inet_ntop");

621

754

} else {

622

755

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

623

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

756

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

624

757

}

625

758

}

626

759

}

627

760

761

if(quit_now){

762

errno = EINTR;

763

goto mandos_end;

764

}

765

628

766

if(af == AF_INET6){

629

767

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

630

768

} else {

631

769

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

632

770

}

633

771

if(ret < 0){

634

perror("connect");

635

return -1;

772

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

773

int e = errno;

774

perror_plus("connect");

775

errno = e;

776

}

777

goto mandos_end;

778

}

779

780

if(quit_now){

781

errno = EINTR;

782

goto mandos_end;

636

783

}

637

784

638

785

const char *out = mandos_protocol_version;

640

787

while(true){

641

788

size_t out_size = strlen(out);

642

789

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

643

out_size - written));

790

out_size - written));

644

791

if(ret == -1){

645

perror("write");

646

retval = -1;

792

int e = errno;

793

perror_plus("write");

794

errno = e;

647

795

goto mandos_end;

648

796

}

649

797

written += (size_t)ret;

657

805

break;

658

806

}

659

807

}

808

809

if(quit_now){

810

errno = EINTR;

811

goto mandos_end;

812

}

660

813

}

661

814

662

815

if(debug){

663

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

664

}

665

816

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

817

}

818

819

if(quit_now){

820

errno = EINTR;

821

goto mandos_end;

822

}

823

824

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

666

825

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

667

826

668

do{

827

if(quit_now){

828

errno = EINTR;

829

goto mandos_end;

830

}

831

832

do {

669

833

ret = gnutls_handshake(session);

834

if(quit_now){

835

errno = EINTR;

836

goto mandos_end;

837

}

670

838

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

671

839

672

840

if(ret != GNUTLS_E_SUCCESS){

673

841

if(debug){

674

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

842

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

675

843

gnutls_perror(ret);

676

844

}

677

retval = -1;

845

errno = EPROTO;

678

846

goto mandos_end;

679

847

}

680

848

681

849

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

682

850

683

851

if(debug){

684

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

685

ip);

852

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

853

" %s\n", ip);

686

854

}

687

855

688

856

while(true){

857

858

if(quit_now){

859

errno = EINTR;

860

goto mandos_end;

861

}

862

689

863

buffer_capacity = incbuffer(&buffer, buffer_length,

690

buffer_capacity);

864

buffer_capacity);

691

865

if(buffer_capacity == 0){

692

perror("incbuffer");

693

retval = -1;

866

int e = errno;

867

perror_plus("incbuffer");

868

errno = e;

869

goto mandos_end;

870

}

871

872

if(quit_now){

873

errno = EINTR;

694

874

goto mandos_end;

695

875

}

696

876

705

885

case GNUTLS_E_AGAIN:

706

886

break;

707

887

case GNUTLS_E_REHANDSHAKE:

708

do{

888

do {

709

889

ret = gnutls_handshake(session);

890

891

if(quit_now){

892

errno = EINTR;

893

goto mandos_end;

894

}

710

895

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

711

896

if(ret < 0){

712

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

897

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

898

"***\n");

713

899

gnutls_perror(ret);

714

retval = -1;

900

errno = EPROTO;

715

901

goto mandos_end;

716

902

}

717

903

break;

718

904

default:

719

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

720

" encrypted session with Mandos server\n");

721

retval = -1;

905

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

906

" encrypted session with Mandos server\n");

722

907

gnutls_bye(session, GNUTLS_SHUT_RDWR);

908

errno = EIO;

723

909

goto mandos_end;

724

910

}

725

911

} else {

728

914

}

729

915

730

916

if(debug){

731

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

732

}

733

734

gnutls_bye(session, GNUTLS_SHUT_RDWR);

917

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

918

}

919

920

if(quit_now){

921

errno = EINTR;

922

goto mandos_end;

923

}

924

925

do {

926

ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);

927

if(quit_now){

928

errno = EINTR;

929

goto mandos_end;

930

}

931

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

735

932

736

933

if(buffer_length > 0){

737

decrypted_buffer_size = pgp_packet_decrypt(buffer,

738

buffer_length,

934

ssize_t decrypted_buffer_size;

935

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

739

936

&decrypted_buffer);

740

937

if(decrypted_buffer_size >= 0){

938

741

939

written = 0;

742

940

while(written < (size_t) decrypted_buffer_size){

941

if(quit_now){

942

errno = EINTR;

943

goto mandos_end;

944

}

945

743

946

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

744

947

(size_t)decrypted_buffer_size - written,

745

948

stdout);

746

949

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

950

int e = errno;

747

951

if(debug){

748

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

749

strerror(errno));

952

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

953

strerror(errno));

750

954

}

751

retval = -1;

752

break;

955

errno = e;

956

goto mandos_end;

753

957

}

754

958

written += (size_t)ret;

755

959

}

756

free(decrypted_buffer);

757

} else {

758

retval = -1;

960

retval = 0;

759

961

}

760

} else {

761

retval = -1;

762

962

}

763

963

764

964

/* Shutdown procedure */

765

965

766

966

mandos_end:

767

free(buffer);

768

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

769

if(ret == -1){

770

perror("close");

967

{

968

int e = errno;

969

free(decrypted_buffer);

970

free(buffer);

971

if(tcp_sd >= 0){

972

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

973

}

974

if(ret == -1){

975

if(e == 0){

976

e = errno;

977

}

978

perror_plus("close");

979

}

980

gnutls_deinit(session);

981

errno = e;

982

if(quit_now){

983

errno = EINTR;

984

retval = -1;

985

}

771

986

}

772

gnutls_deinit(session);

773

987

return retval;

774

988

}

775

989

786

1000

AVAHI_GCC_UNUSED AvahiStringList *txt,

787

1001

AVAHI_GCC_UNUSED AvahiLookupResultFlags

788

1002

flags,

789

__attribute__((unused)) void* userdata){

1003

AVAHI_GCC_UNUSED void* userdata){

790

1004

assert(r);

791

1005

792

1006

/* Called whenever a service has been resolved successfully or

793

1007

timed out */

794

1008

1009

if(quit_now){

1010

return;

1011

}

1012

795

1013

switch(event){

796

1014

default:

797

1015

case AVAHI_RESOLVER_FAILURE:

798

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

799

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

800

avahi_strerror(avahi_server_errno(mc.server)));

1016

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

1017

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

1018

domain,

1019

avahi_strerror(avahi_server_errno(mc.server)));

801

1020

break;

802

1021

803

1022

case AVAHI_RESOLVER_FOUND:

805

1024

char ip[AVAHI_ADDRESS_STR_MAX];

806

1025

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

807

1026

if(debug){

808

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

809

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

810

ip, (intmax_t)interface, port);

1027

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

1028

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

1029

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

811

1030

}

812

1031

int ret = start_mandos_communication(ip, port, interface,

813

1032

avahi_proto_to_af(proto));

814

1033

if(ret == 0){

815

1034

avahi_simple_poll_quit(mc.simple_poll);

1035

} else {

1036

if(not add_server(ip, port, interface,

1037

avahi_proto_to_af(proto))){

1038

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

1039

" list\n", name);

1040

}

816

1041

}

817

1042

}

818

1043

}

828

1053

const char *domain,

829

1054

AVAHI_GCC_UNUSED AvahiLookupResultFlags

830

1055

flags,

831

__attribute__((unused)) void* userdata){

1056

AVAHI_GCC_UNUSED void* userdata){

832

1057

assert(b);

833

1058

834

1059

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

835

1060

is removed from the LAN */

836

1061

1062

if(quit_now){

1063

return;

1064

}

1065

837

1066

switch(event){

838

1067

default:

839

1068

case AVAHI_BROWSER_FAILURE:

840

1069

841

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

842

avahi_strerror(avahi_server_errno(mc.server)));

1070

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

1071

avahi_strerror(avahi_server_errno(mc.server)));

843

1072

avahi_simple_poll_quit(mc.simple_poll);

844

1073

return;

845

1074

849

1078

the callback function is called the Avahi server will free the

850

1079

resolver for us. */

851

1080

852

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

853

protocol, name, type, domain,

854

AVAHI_PROTO_INET6, 0,

855

resolve_callback, NULL)))

856

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

857

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

1081

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

1082

name, type, domain, protocol, 0,

1083

resolve_callback, NULL) == NULL)

1084

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

1085

" %s\n", name,

1086

avahi_strerror(avahi_server_errno(mc.server)));

858

1087

break;

859

1088

860

1089

case AVAHI_BROWSER_REMOVE:

863

1092

case AVAHI_BROWSER_ALL_FOR_NOW:

864

1093

case AVAHI_BROWSER_CACHE_EXHAUSTED:

865

1094

if(debug){

866

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

1095

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

1096

" searching...\n");

867

1097

}

868

1098

break;

869

1099

}

870

1100

}

871

1101

872

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

1102

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

1103

static void handle_sigterm(int sig){

1104

if(quit_now){

1105

return;

1106

}

1107

quit_now = 1;

1108

signal_received = sig;

873

1109

int old_errno = errno;

874

avahi_simple_poll_quit(mc.simple_poll);

1110

/* set main loop to exit */

1111

if(mc.simple_poll != NULL){

1112

avahi_simple_poll_quit(mc.simple_poll);

1113

}

875

1114

errno = old_errno;

876

1115

}

877

1116

1117

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

1118

int ret;

1119

1120

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

1121

if(s < 0){

1122

perror_plus("socket");

1123

return false;

1124

}

1125

strcpy(ifr->ifr_name, ifname);

1126

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1127

if(ret == -1){

1128

if(debug){

1129

perror_plus("ioctl SIOCGIFFLAGS");

1130

}

1131

return false;

1132

}

1133

return true;

1134

}

1135

1136

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

1137

1138

/* Reject the loopback device */

1139

if(ifr->ifr_flags & IFF_LOOPBACK){

1140

if(debug){

1141

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

1142

ifname);

1143

}

1144

return false;

1145

}

1146

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

1147

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

1148

if(debug){

1149

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

1150

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

1151

}

1152

return true;

1153

}

1154

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

1155

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

1156

if(debug){

1157

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1158

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

1159

}

1160

return false;

1161

}

1162

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

1163

if(ifr->ifr_flags & IFF_NOARP){

1164

if(debug){

1165

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

1166

ifname);

1167

}

1168

return false;

1169

}

1170

1171

/* Accept this device */

1172

if(debug){

1173

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

1174

}

1175

return true;

1176

}

1177

1178

/*

1179

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

1180

* corresponds to an acceptable network device.

1181

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

1182

*/

1183

int good_interface(const struct dirent *if_entry){

1184

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

1185

return 0;

1186

}

1187

1188

struct ifreq ifr;

1189

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

1190

if(debug){

1191

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

1192

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

1193

}

1194

return 0;

1195

}

1196

1197

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

1198

return 0;

1199

}

1200

return 1;

1201

}

1202

1203

/*

1204

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

1205

* corresponds to an acceptable network device which is up.

1206

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

1207

*/

1208

int up_interface(const struct dirent *if_entry){

1209

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

1210

return 0;

1211

}

1212

1213

struct ifreq ifr;

1214

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

1215

if(debug){

1216

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

1217

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

1218

}

1219

return 0;

1220

}

1221

1222

/* Reject down interfaces */

1223

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

1224

if(debug){

1225

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

1226

if_entry->d_name);

1227

}

1228

return 0;

1229

}

1230

1231

/* Reject non-running interfaces */

1232

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

1233

if(debug){

1234

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

1235

if_entry->d_name);

1236

}

1237

return 0;

1238

}

1239

1240

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

1241

return 0;

1242

}

1243

return 1;

1244

}

1245

1246

int notdotentries(const struct dirent *direntry){

1247

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

1248

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

1249

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

1250

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

1251

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

1252

return 0;

1253

}

1254

return 1;

1255

}

1256

1257

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

1258

int runnable_hook(const struct dirent *direntry){

1259

int ret;

1260

size_t sret;

1261

struct stat st;

1262

1263

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

1264

/* Empty name? */

1265

return 0;

1266

}

1267

1268

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

1269

"abcdefghijklmnopqrstuvwxyz"

1270

"0123456789"

1271

"_-");

1272

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

1273

/* Contains non-allowed characters */

1274

if(debug){

1275

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

1276

direntry->d_name);

1277

}

1278

return 0;

1279

}

1280

1281

char *fullname = NULL;

1282

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

1283

if(ret < 0){

1284

perror_plus("asprintf");

1285

return 0;

1286

}

1287

1288

ret = stat(fullname, &st);

1289

if(ret == -1){

1290

if(debug){

1291

perror_plus("Could not stat hook");

1292

}

1293

return 0;

1294

}

1295

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

1296

/* Not a regular file */

1297

if(debug){

1298

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

1299

direntry->d_name);

1300

}

1301

return 0;

1302

}

1303

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

1304

/* Not executable */

1305

if(debug){

1306

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

1307

direntry->d_name);

1308

}

1309

return 0;

1310

}

1311

if(debug){

1312

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

1313

direntry->d_name);

1314

}

1315

return 1;

1316

}

1317

1318

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1319

int ret;

1320

struct timespec now;

1321

struct timespec waited_time;

1322

intmax_t block_time;

1323

1324

while(true){

1325

if(mc.current_server == NULL){

1326

if (debug){

1327

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

1328

" No timeout!\n");

1329

}

1330

ret = avahi_simple_poll_iterate(s, -1);

1331

} else {

1332

if (debug){

1333

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

1334

" it, or wait\n");

1335

}

1336

/* the current time */

1337

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1338

if(ret == -1){

1339

perror_plus("clock_gettime");

1340

return -1;

1341

}

1342

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

1343

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

1344

waited_time.tv_sec = (now.tv_sec

1345

- mc.current_server->last_seen.tv_sec);

1346

waited_time.tv_nsec = (now.tv_nsec

1347

- mc.current_server->last_seen.tv_nsec);

1348

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

1349

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

1350

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

1351

block_time = ((retry_interval

1352

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

1353

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

1354

1355

if (debug){

1356

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

1357

block_time);

1358

}

1359

1360

if(block_time <= 0){

1361

ret = start_mandos_communication(mc.current_server->ip,

1362

mc.current_server->port,

1363

mc.current_server->if_index,

1364

mc.current_server->af);

1365

if(ret == 0){

1366

avahi_simple_poll_quit(mc.simple_poll);

1367

return 0;

1368

}

1369

ret = clock_gettime(CLOCK_MONOTONIC,

1370

&mc.current_server->last_seen);

1371

if(ret == -1){

1372

perror_plus("clock_gettime");

1373

return -1;

1374

}

1375

mc.current_server = mc.current_server->next;

1376

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

1377

servers, but don't block */

1378

}

1379

1380

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

1381

}

1382

if(ret != 0){

1383

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

1384

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

1385

}

1386

}

1387

}

1388

}

1389

1390

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

1391

const float delay){

1392

struct dirent **direntries;

1393

struct dirent *direntry;

1394

int ret;

1395

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

1396

alphasort);

1397

if(numhooks == -1){

1398

perror_plus("scandir");

1399

} else {

1400

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

1401

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

1402

direntry = direntries[i];

1403

char *fullname = NULL;

1404

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

1405

if(ret < 0){

1406

perror_plus("asprintf");

1407

continue;

1408

}

1409

if(debug){

1410

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

1411

direntry->d_name);

1412

}

1413

pid_t hook_pid = fork();

1414

if(hook_pid == 0){

1415

/* Child */

1416

/* Raise privileges */

1417

errno = 0;

1418

ret = seteuid(0);

1419

if(ret == -1){

1420

perror_plus("seteuid");

1421

}

1422

/* Raise privileges even more */

1423

errno = 0;

1424

ret = setuid(0);

1425

if(ret == -1){

1426

perror_plus("setuid");

1427

}

1428

/* Set group */

1429

errno = 0;

1430

ret = setgid(0);

1431

if(ret == -1){

1432

perror_plus("setgid");

1433

}

1434

/* Reset supplementary groups */

1435

errno = 0;

1436

ret = setgroups(0, NULL);

1437

if(ret == -1){

1438

perror_plus("setgroups");

1439

}

1440

dup2(devnull, STDIN_FILENO);

1441

close(devnull);

1442

dup2(STDERR_FILENO, STDOUT_FILENO);

1443

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

1444

if(ret == -1){

1445

perror_plus("setenv");

1446

_exit(EX_OSERR);

1447

}

1448

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

1449

if(ret == -1){

1450

perror_plus("setenv");

1451

_exit(EX_OSERR);

1452

}

1453

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

1454

if(ret == -1){

1455

perror_plus("setenv");

1456

_exit(EX_OSERR);

1457

}

1458

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

1459

if(ret == -1){

1460

perror_plus("setenv");

1461

_exit(EX_OSERR);

1462

}

1463

char *delaystring;

1464

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

1465

if(ret == -1){

1466

perror_plus("asprintf");

1467

_exit(EX_OSERR);

1468

}

1469

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

1470

if(ret == -1){

1471

free(delaystring);

1472

perror_plus("setenv");

1473

_exit(EX_OSERR);

1474

}

1475

free(delaystring);

1476

if(connect_to != NULL){

1477

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

1478

if(ret == -1){

1479

perror_plus("setenv");

1480

_exit(EX_OSERR);

1481

}

1482

}

1483

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

1484

perror_plus("execl");

1485

_exit(EXIT_FAILURE);

1486

}

1487

} else {

1488

int status;

1489

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

1490

perror_plus("waitpid");

1491

free(fullname);

1492

continue;

1493

}

1494

if(WIFEXITED(status)){

1495

if(WEXITSTATUS(status) != 0){

1496

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

1497

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

1498

WEXITSTATUS(status));

1499

free(fullname);

1500

continue;

1501

}

1502

} else if(WIFSIGNALED(status)){

1503

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

1504

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

1505

WTERMSIG(status));

1506

free(fullname);

1507

continue;

1508

} else {

1509

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

1510

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

1511

free(fullname);

1512

continue;

1513

}

1514

}

1515

free(fullname);

1516

if(debug){

1517

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

1518

direntry->d_name);

1519

}

1520

}

1521

close(devnull);

1522

}

1523

return true;

1524

}

1525

878

1526

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

879

1527

AvahiSServiceBrowser *sb = NULL;

880

1528

int error;

881

1529

int ret;

882

1530

intmax_t tmpmax;

883

int numchars;

1531

char *tmp;

884

1532

int exitcode = EXIT_SUCCESS;

885

const char *interface = "eth0";

1533

const char *interface = "";

886

1534

struct ifreq network;

887

int sd;

1535

int sd = -1;

1536

bool take_down_interface = false;

888

1537

uid_t uid;

889

1538

gid_t gid;

890

char *connect_to = NULL;

891

1539

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

892

1540

bool tempdir_created = false;

893

1541

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

896

1544

897

1545

bool gnutls_initialized = false;

898

1546

bool gpgme_initialized = false;

899

double delay = 2.5;

900

901

struct sigaction old_sigterm_action;

1547

float delay = 2.5f;

1548

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

1549

retrying the same server again */

1550

1551

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

902

1552

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

903

904

/* Initialize mandos context */

905

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

906

.dh_bits = 1024, .priority = "SECURE256"

907

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

1553

1554

uid = getuid();

1555

gid = getgid();

1556

1557

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

1558

errno = 0;

1559

ret = setgid(gid);

1560

if(ret == -1){

1561

perror_plus("setgid");

1562

}

1563

1564

/* Lower user privileges (temporarily) */

1565

errno = 0;

1566

ret = seteuid(uid);

1567

if(ret == -1){

1568

perror_plus("seteuid");

1569

}

1570

1571

if(quit_now){

1572

goto end;

1573

}

908

1574

909

1575

{

910

1576

struct argp_option options[] = {

940

1606

.arg = "SECONDS",

941

1607

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

942

1608

.group = 2 },

1609

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

1610

.arg = "SECONDS",

1611

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

1612

.group = 2 },

1613

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

1614

.arg = "DIR",

1615

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

1616

.group = 2 },

1617

/*

1618

* These reproduce what we would get without ARGP_NO_HELP

1619

*/

1620

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

1621

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

1622

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

1623

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

1624

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

1625

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

943

1626

{ .name = NULL }

944

1627

};

945

1628

946

1629

error_t parse_opt(int key, char *arg,

947

1630

struct argp_state *state){

1631

errno = 0;

948

1632

switch(key){

949

1633

case 128: /* --debug */

950

1634

debug = true;

962

1646

pubkey = arg;

963

1647

break;

964

1648

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

965

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

966

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

967

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

968

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

969

exit(EXIT_FAILURE);

1649

errno = 0;

1650

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

1651

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

1652

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

1653

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

970

1654

}

971

1655

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

972

1656

break;

974

1658

mc.priority = arg;

975

1659

break;

976

1660

case 131: /* --delay */

977

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

978

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

979

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

980

exit(EXIT_FAILURE);

981

}

982

break;

983

case ARGP_KEY_ARG:

984

argp_usage(state);

985

case ARGP_KEY_END:

1661

errno = 0;

1662

delay = strtof(arg, &tmp);

1663

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

1664

argp_error(state, "Bad delay");

1665

}

1666

case 132: /* --retry */

1667

errno = 0;

1668

retry_interval = strtod(arg, &tmp);

1669

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

1670

or (retry_interval * 1000) > INT_MAX

1671

or retry_interval < 0){

1672

argp_error(state, "Bad retry interval");

1673

}

1674

break;

1675

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

1676

hookdir = arg;

1677

break;

1678

/*

1679

* These reproduce what we would get without ARGP_NO_HELP

1680

*/

1681

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

1682

argp_state_help(state, state->out_stream,

1683

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

1684

& ~(unsigned int)ARGP_HELP_EXIT_OK);

1685

case -3: /* --usage */

1686

argp_state_help(state, state->out_stream,

1687

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1688

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

1689

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

1690

exit(argp_err_exit_status);

986

1691

break;

987

1692

default:

988

1693

return ARGP_ERR_UNKNOWN;

989

1694

}

990

return 0;

1695

return errno;

991

1696

}

992

1697

993

1698

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

994

1699

.args_doc = "",

995

1700

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

996

1701

" passwords from a Mandos server" };

997

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

998

if(ret == ARGP_ERR_UNKNOWN){

999

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

1702

ret = argp_parse(&argp, argc, argv,

1703

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1704

switch(ret){

1705

case 0:

1706

break;

1707

case ENOMEM:

1708

default:

1709

errno = ret;

1710

perror_plus("argp_parse");

1711

exitcode = EX_OSERR;

1712

goto end;

1713

case EINVAL:

1714

exitcode = EX_USAGE;

1715

goto end;

1716

}

1717

}

1718

1719

{

1720

/* Work around Debian bug #633582:

1721

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

1722

1723

/* Re-raise priviliges */

1724

errno = 0;

1725

ret = seteuid(0);

1726

if(ret == -1){

1727

perror_plus("seteuid");

1728

} else {

1729

struct stat st;

1730

1731

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

1732

int seckey_fd = open(seckey, O_RDONLY);

1733

if(seckey_fd == -1){

1734

perror_plus("open");

1735

} else {

1736

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

1737

if(ret == -1){

1738

perror_plus("fstat");

1739

} else {

1740

if(S_ISREG(st.st_mode)

1741

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

1742

ret = fchown(seckey_fd, uid, gid);

1743

if(ret == -1){

1744

perror_plus("fchown");

1745

}

1746

}

1747

}

1748

TEMP_FAILURE_RETRY(close(seckey_fd));

1749

}

1750

}

1751

1752

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

1753

int pubkey_fd = open(pubkey, O_RDONLY);

1754

if(pubkey_fd == -1){

1755

perror_plus("open");

1756

} else {

1757

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

1758

if(ret == -1){

1759

perror_plus("fstat");

1760

} else {

1761

if(S_ISREG(st.st_mode)

1762

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

1763

ret = fchown(pubkey_fd, uid, gid);

1764

if(ret == -1){

1765

perror_plus("fchown");

1766

}

1767

}

1768

}

1769

TEMP_FAILURE_RETRY(close(pubkey_fd));

1770

}

1771

}

1772

1773

/* Lower privileges */

1774

errno = 0;

1775

ret = seteuid(uid);

1776

if(ret == -1){

1777

perror_plus("seteuid");

1778

}

1779

}

1780

}

1781

1782

/* Run network hooks */

1783

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

1784

goto end;

1785

}

1786

1787

if(not debug){

1788

avahi_set_log_function(empty_log);

1789

}

1790

1791

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

1792

struct dirent **direntries;

1793

/* First look for interfaces that are up */

1794

ret = scandir(sys_class_net, &direntries, up_interface,

1795

alphasort);

1796

if(ret == 0){

1797

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

1798

free(direntries);

1799

ret = scandir(sys_class_net, &direntries, good_interface,

1800

alphasort);

1801

}

1802

if(ret >= 1){

1803

/* Pick the first interface returned */

1804

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

1805

if(debug){

1806

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

1807

}

1808

if(interface == NULL){

1809

perror_plus("malloc");

1810

free(direntries);

1811

exitcode = EXIT_FAILURE;

1812

goto end;

1813

}

1814

free(direntries);

1815

} else {

1816

free(direntries);

1817

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

1000

1818

exitcode = EXIT_FAILURE;

1001

1819

goto end;

1002

1820

}

1003

1821

}

1004

1822

1823

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

1824

from the signal handler */

1825

/* Initialize the pseudo-RNG for Avahi */

1826

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

1827

mc.simple_poll = avahi_simple_poll_new();

1828

if(mc.simple_poll == NULL){

1829

fprintf_plus(stderr,

1830

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

1831

exitcode = EX_UNAVAILABLE;

1832

goto end;

1833

}

1834

1835

sigemptyset(&sigterm_action.sa_mask);

1836

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

1837

if(ret == -1){

1838

perror_plus("sigaddset");

1839

exitcode = EX_OSERR;

1840

goto end;

1841

}

1842

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

1843

if(ret == -1){

1844

perror_plus("sigaddset");

1845

exitcode = EX_OSERR;

1846

goto end;

1847

}

1848

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

1849

if(ret == -1){

1850

perror_plus("sigaddset");

1851

exitcode = EX_OSERR;

1852

goto end;

1853

}

1854

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

1855

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

1856

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

1857

*/

1858

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

1859

if(ret == -1){

1860

perror_plus("sigaction");

1861

return EX_OSERR;

1862

}

1863

if(old_sigterm_action.sa_handler != SIG_IGN){

1864

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

1865

if(ret == -1){

1866

perror_plus("sigaction");

1867

exitcode = EX_OSERR;

1868

goto end;

1869

}

1870

}

1871

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

1872

if(ret == -1){

1873

perror_plus("sigaction");

1874

return EX_OSERR;

1875

}

1876

if(old_sigterm_action.sa_handler != SIG_IGN){

1877

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

1878

if(ret == -1){

1879

perror_plus("sigaction");

1880

exitcode = EX_OSERR;

1881

goto end;

1882

}

1883

}

1884

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

1885

if(ret == -1){

1886

perror_plus("sigaction");

1887

return EX_OSERR;

1888

}

1889

if(old_sigterm_action.sa_handler != SIG_IGN){

1890

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

1891

if(ret == -1){

1892

perror_plus("sigaction");

1893

exitcode = EX_OSERR;

1894

goto end;

1895

}

1896

}

1897

1005

1898

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

1006

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

1899

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

1900

if_index = (AvahiIfIndex) if_nametoindex(interface);

1901

if(if_index == 0){

1902

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

1903

exitcode = EX_UNAVAILABLE;

1904

goto end;

1905

}

1906

1907

if(quit_now){

1908

goto end;

1909

}

1910

1911

/* Re-raise priviliges */

1912

errno = 0;

1913

ret = seteuid(0);

1914

if(ret == -1){

1915

perror_plus("seteuid");

1916

}

1917

1007

1918

#ifdef __linux__

1008

1919

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1009

messages to mess up the prompt */

1920

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

1010

1921

ret = klogctl(8, NULL, 5);

1011

1922

bool restore_loglevel = true;

1012

1923

if(ret == -1){

1013

1924

restore_loglevel = false;

1014

perror("klogctl");

1925

perror_plus("klogctl");

1015

1926

}

1016

#endif

1927

#endif /* __linux__ */

1017

1928

1018

1929

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1019

1930

if(sd < 0){

1020

perror("socket");

1021

exitcode = EXIT_FAILURE;

1931

perror_plus("socket");

1932

exitcode = EX_OSERR;

1022

1933

#ifdef __linux__

1023

1934

if(restore_loglevel){

1024

1935

ret = klogctl(7, NULL, 0);

1025

1936

if(ret == -1){

1026

perror("klogctl");

1937

perror_plus("klogctl");

1027

1938

}

1028

1939

}

1029

#endif

1940

#endif /* __linux__ */

1941

/* Lower privileges */

1942

errno = 0;

1943

ret = seteuid(uid);

1944

if(ret == -1){

1945

perror_plus("seteuid");

1946

}

1030

1947

goto end;

1031

1948

}

1032

1949

strcpy(network.ifr_name, interface);

1033

1950

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

1034

1951

if(ret == -1){

1035

perror("ioctl SIOCGIFFLAGS");

1952

perror_plus("ioctl SIOCGIFFLAGS");

1036

1953

#ifdef __linux__

1037

1954

if(restore_loglevel){

1038

1955

ret = klogctl(7, NULL, 0);

1039

1956

if(ret == -1){

1040

perror("klogctl");

1957

perror_plus("klogctl");

1041

1958

}

1042

1959

}

1043

#endif

1044

exitcode = EXIT_FAILURE;

1960

#endif /* __linux__ */

1961

exitcode = EX_OSERR;

1962

/* Lower privileges */

1963

errno = 0;

1964

ret = seteuid(uid);

1965

if(ret == -1){

1966

perror_plus("seteuid");

1967

}

1045

1968

goto end;

1046

1969

}

1047

1970

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

1048

1971

network.ifr_flags |= IFF_UP;

1972

take_down_interface = true;

1049

1973

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

1050

1974

if(ret == -1){

1051

perror("ioctl SIOCSIFFLAGS");

1052

exitcode = EXIT_FAILURE;

1975

take_down_interface = false;

1976

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1977

exitcode = EX_OSERR;

1053

1978

#ifdef __linux__

1054

1979

if(restore_loglevel){

1055

1980

ret = klogctl(7, NULL, 0);

1056

1981

if(ret == -1){

1057

perror("klogctl");

1982

perror_plus("klogctl");

1058

1983

}

1059

1984

}

1060

#endif

1985

#endif /* __linux__ */

1986

/* Lower privileges */

1987

errno = 0;

1988

ret = seteuid(uid);

1989

if(ret == -1){

1990

perror_plus("seteuid");

1991

}

1061

1992

goto end;

1062

1993

}

1063

1994

}

1064

/* sleep checking until interface is running */

1995

/* Sleep checking until interface is running.

1996

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

1065

1997

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

1066

1998

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

1067

1999

if(ret == -1){

1068

perror("ioctl SIOCGIFFLAGS");

2000

perror_plus("ioctl SIOCGIFFLAGS");

1069

2001

} else if(network.ifr_flags & IFF_RUNNING){

1070

2002

break;

1071

2003

}

1072

2004

struct timespec sleeptime = { .tv_nsec = 250000000 };

1073

2005

ret = nanosleep(&sleeptime, NULL);

1074

2006

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

1075

perror("nanosleep");

2007

perror_plus("nanosleep");

1076

2008

}

1077

2009

}

1078

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

1079

if(ret == -1){

1080

perror("close");

2010

if(not take_down_interface){

2011

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

2012

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

2013

if(ret == -1){

2014

perror_plus("close");

2015

}

1081

2016

}

1082

2017

#ifdef __linux__

1083

2018

if(restore_loglevel){

1084

2019

/* Restores kernel loglevel to default */

1085

2020

ret = klogctl(7, NULL, 0);

1086

2021

if(ret == -1){

1087

perror("klogctl");

2022

perror_plus("klogctl");

1088

2023

}

1089

2024

}

1090

#endif

1091

}

1092

1093

uid = getuid();

1094

gid = getgid();

1095

1096

errno = 0;

1097

setgid(gid);

1098

if(ret == -1){

1099

perror("setgid");

1100

}

1101

1102

ret = setuid(uid);

1103

if(ret == -1){

1104

perror("setuid");

2025

#endif /* __linux__ */

2026

/* Lower privileges */

2027

errno = 0;

2028

/* Lower privileges */

2029

ret = seteuid(uid);

2030

if(ret == -1){

2031

perror_plus("seteuid");

2032

}

2033

}

2034

2035

if(quit_now){

2036

goto end;

1105

2037

}

1106

2038

1107

2039

ret = init_gnutls_global(pubkey, seckey);

1108

2040

if(ret == -1){

1109

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

1110

exitcode = EXIT_FAILURE;

2041

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

2042

exitcode = EX_UNAVAILABLE;

1111

2043

goto end;

1112

2044

} else {

1113

2045

gnutls_initialized = true;

1114

2046

}

1115

2047

2048

if(quit_now){

2049

goto end;

2050

}

2051

1116

2052

if(mkdtemp(tempdir) == NULL){

1117

perror("mkdtemp");

2053

perror_plus("mkdtemp");

1118

2054

goto end;

1119

2055

}

1120

2056

tempdir_created = true;

1121

2057

2058

if(quit_now){

2059

goto end;

2060

}

2061

1122

2062

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

1123

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

1124

exitcode = EXIT_FAILURE;

2063

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

2064

exitcode = EX_UNAVAILABLE;

1125

2065

goto end;

1126

2066

} else {

1127

2067

gpgme_initialized = true;

1128

2068

}

1129

2069

1130

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

1131

if_index = (AvahiIfIndex) if_nametoindex(interface);

1132

if(if_index == 0){

1133

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

1134

exitcode = EXIT_FAILURE;

1135

goto end;

1136

}

2070

if(quit_now){

2071

goto end;

1137

2072

}

1138

2073

1139

2074

if(connect_to != NULL){

1141

2076

/* (Mainly meant for debugging) */

1142

2077

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

1143

2078

if(address == NULL){

1144

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

1145

exitcode = EXIT_FAILURE;

1146

goto end;

1147

}

2079

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

2080

exitcode = EX_USAGE;

2081

goto end;

2082

}

2083

2084

if(quit_now){

2085

goto end;

2086

}

2087

1148

2088

uint16_t port;

1149

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

1150

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

1151

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

1152

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

1153

exitcode = EXIT_FAILURE;

1154

goto end;

1155

}

2089

errno = 0;

2090

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

2091

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

2092

or tmpmax != (uint16_t)tmpmax){

2093

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

2094

exitcode = EX_USAGE;

2095

goto end;

2096

}

2097

2098

if(quit_now){

2099

goto end;

2100

}

2101

1156

2102

port = (uint16_t)tmpmax;

1157

2103

*address = '\0';

1158

address = connect_to;

1159

2104

/* Colon in address indicates IPv6 */

1160

2105

int af;

1161

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

2106

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

1162

2107

af = AF_INET6;

2108

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

2109

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

2110

{

2111

connect_to++;

2112

address[-1] = '\0';

2113

}

1163

2114

} else {

1164

2115

af = AF_INET;

1165

2116

}

1166

ret = start_mandos_communication(address, port, if_index,

1167

af);

1168

if(ret < 0){

1169

exitcode = EXIT_FAILURE;

1170

} else {

2117

address = connect_to;

2118

2119

if(quit_now){

2120

goto end;

2121

}

2122

2123

while(not quit_now){

2124

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

2125

if(quit_now or ret == 0){

2126

break;

2127

}

2128

if(debug){

2129

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

2130

(int)retry_interval);

2131

}

2132

sleep((int)retry_interval);

2133

}

2134

2135

if (not quit_now){

1171

2136

exitcode = EXIT_SUCCESS;

1172

2137

}

2138

1173

2139

goto end;

1174

2140

}

1175

2141

1176

if(not debug){

1177

avahi_set_log_function(empty_log);

1178

}

1179

1180

/* Initialize the pseudo-RNG for Avahi */

1181

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

1182

1183

/* Allocate main Avahi loop object */

1184

mc.simple_poll = avahi_simple_poll_new();

1185

if(mc.simple_poll == NULL){

1186

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

1187

exitcode = EXIT_FAILURE;

2142

if(quit_now){

1188

2143

goto end;

1189

2144

}

1190

2145

1208

2163

1209

2164

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

1210

2165

if(mc.server == NULL){

1211

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

1212

avahi_strerror(error));

1213

exitcode = EXIT_FAILURE;

2166

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

2167

avahi_strerror(error));

2168

exitcode = EX_UNAVAILABLE;

2169

goto end;

2170

}

2171

2172

if(quit_now){

1214

2173

goto end;

1215

2174

}

1216

2175

1217

2176

/* Create the Avahi service browser */

1218

2177

sb = avahi_s_service_browser_new(mc.server, if_index,

1219

AVAHI_PROTO_INET6, "_mandos._tcp",

2178

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1220

2179

NULL, 0, browse_callback, NULL);

1221

2180

if(sb == NULL){

1222

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

1223

avahi_strerror(avahi_server_errno(mc.server)));

1224

exitcode = EXIT_FAILURE;

1225

goto end;

1226

}

1227

1228

sigemptyset(&sigterm_action.sa_mask);

1229

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

1230

if(ret == -1){

1231

perror("sigaddset");

1232

exitcode = EXIT_FAILURE;

1233

goto end;

1234

}

1235

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

1236

if(ret == -1){

1237

perror("sigaction");

1238

exitcode = EXIT_FAILURE;

1239

goto end;

1240

}

2181

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

2182

avahi_strerror(avahi_server_errno(mc.server)));

2183

exitcode = EX_UNAVAILABLE;

2184

goto end;

2185

}

2186

2187

if(quit_now){

2188

goto end;

2189

}

1241

2190

1242

2191

/* Run the main loop */

1243

2192

1244

2193

if(debug){

1245

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

1246

}

1247

1248

avahi_simple_poll_loop(mc.simple_poll);

2194

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

2195

}

2196

2197

ret = avahi_loop_with_timeout(mc.simple_poll,

2198

(int)(retry_interval * 1000));

2199

if(debug){

2200

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

2201

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

2202

}

1249

2203

1250

2204

end:

1251

2205

1252

2206

if(debug){

1253

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

2207

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

1254

2208

}

1255

2209

1256

2210

/* Cleanup things */

1273

2227

gpgme_release(mc.ctx);

1274

2228

}

1275

2229

1276

/* Removes the temp directory used by GPGME */

2230

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

2231

has seen */

2232

if(mc.current_server != NULL){

2233

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

2234

while(mc.current_server != NULL){

2235

server *next = mc.current_server->next;

2236

free(mc.current_server);

2237

mc.current_server = next;

2238

}

2239

}

2240

2241

/* Run network hooks */

2242

run_network_hooks("stop", interface, delay);

2243

2244

/* Re-raise priviliges */

2245

{

2246

errno = 0;

2247

ret = seteuid(0);

2248

if(ret == -1){

2249

perror_plus("seteuid");

2250

}

2251

2252

/* Take down the network interface */

2253

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

2254

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

2255

if(ret == -1){

2256

perror_plus("ioctl SIOCGIFFLAGS");

2257

} else if(network.ifr_flags & IFF_UP){

2258

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

2259

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

2260

if(ret == -1){

2261

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2262

}

2263

}

2264

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

2265

if(ret == -1){

2266

perror_plus("close");

2267

}

2268

}

2269

}

2270

/* Lower privileges permanently */

2271

errno = 0;

2272

ret = setuid(uid);

2273

if(ret == -1){

2274

perror_plus("setuid");

2275

}

2276

2277

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

1277

2278

if(tempdir_created){

1278

DIR *d;

1279

struct dirent *direntry;

1280

d = opendir(tempdir);

1281

if(d == NULL){

1282

if(errno != ENOENT){

1283

perror("opendir");

1284

}

1285

} else {

1286

while(true){

1287

direntry = readdir(d);

1288

if(direntry == NULL){

1289

break;

1290

}

1291

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

1292

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

1293

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

1294

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

1295

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

1296

continue;

1297

}

2279

struct dirent **direntries = NULL;

2280

struct dirent *direntry = NULL;

2281

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

2282

alphasort);

2283

if (numentries > 0){

2284

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

2285

direntry = direntries[i];

1298

2286

char *fullname = NULL;

1299

2287

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

1300

2288

direntry->d_name);

1301

2289

if(ret < 0){

1302

perror("asprintf");

2290

perror_plus("asprintf");

1303

2291

continue;

1304

2292

}

1305

2293

ret = remove(fullname);

1306

2294

if(ret == -1){

1307

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

1308

strerror(errno));

2295

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

2296

strerror(errno));

1309

2297

}

1310

2298

free(fullname);

1311

2299

}

1312

closedir(d);

2300

}

2301

2302

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

2303

free(direntries);

2304

if (numentries == -1){

2305

perror_plus("scandir");

1313

2306

}

1314

2307

ret = rmdir(tempdir);

1315

2308

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

1316

perror("rmdir");

1317

}

2309

perror_plus("rmdir");

2310

}

2311

}

2312

2313

if(quit_now){

2314

sigemptyset(&old_sigterm_action.sa_mask);

2315

old_sigterm_action.sa_handler = SIG_DFL;

2316

ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,

2317

&old_sigterm_action,

2318

NULL));

2319

if(ret == -1){

2320

perror_plus("sigaction");

2321

}

2322

do {

2323

ret = raise(signal_received);

2324

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

2325

if(ret != 0){

2326

perror_plus("raise");

2327

abort();

2328

}

2329

TEMP_FAILURE_RETRY(pause());

1318

2330

}

1319

2331

1320

2332

return exitcode;