/mandos/trunk : revision 738.1.2

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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

32

/* 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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#endif /* not _LARGEFILE_SOURCE */

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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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#endif /* not _FILE_OFFSET_BITS */

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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(), remove() */

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

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stdout, ferror() */

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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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inet_pton(), connect(),

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getnameinfo() */

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

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

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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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program_invocation_short_name */

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

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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, inet_ntop() */

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setgid(), pause(), _exit(),

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unlinkat() */

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

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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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#include <netdb.h> /* getnameinfo(), NI_NUMERICHOST,

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EAI_SYSTEM, gai_strerror() */

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#ifdef __linux__

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

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init_gnutls_session(),

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GNUTLS_* */

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#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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133

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

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#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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137

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bool debug = false;

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139

static const char mandos_protocol_version[] = "1";

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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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int hookdir_fd = -1;

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uid_t uid = 65534;

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gid_t gid = 65534;

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

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150

typedef struct server{

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151

const char *ip;

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uint16_t port;

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

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typedef struct {

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AvahiSimplePoll *simple_poll;

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AvahiServer *server;

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gnutls_certificate_credentials_t cred;

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unsigned int dh_bits;

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const char *priority;

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gpgme_ctx_t ctx;

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168

server *current_server;

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char *interfaces;

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size_t interfaces_size;

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171

} mandos_context;

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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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.current_server = NULL };

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/* global so signal handler can reach it*/

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AvahiSimplePoll *simple_poll;

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sig_atomic_t quit_now = 0;

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int signal_received = 0;

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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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183

program_invocation_short_name);

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errno = e;

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perror(print_text);

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}

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

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

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program_invocation_short_name));

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

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}

197

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/*

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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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201

* "buffer_length" is how much is already used.

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202

*/

203

__attribute__((nonnull, warn_unused_result))

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204

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){

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206

if(buffer_length + BUFFER_SIZE > buffer_capacity){

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

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if(buffer == NULL){

207

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

208

if(new_buf == NULL){

209

int old_errno = errno;

210

free(*buffer);

211

errno = old_errno;

212

*buffer = NULL;

183

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return 0;

184

214

}

215

*buffer = new_buf;

185

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buffer_capacity += BUFFER_SIZE;

186

217

}

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218

return buffer_capacity;

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219

}

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

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int add_server(const char *ip, uint16_t port,

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AvahiIfIndex if_index,

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int af){

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__attribute__((nonnull, warn_unused_result))

223

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));

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if(new_server == NULL){

197

228

perror_plus("malloc");

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return -1;

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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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.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){

205

236

perror_plus("strdup");

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return -1;

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free(new_server);

238

return false;

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}

240

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

241

if(ret == -1){

242

perror_plus("clock_gettime");

243

#ifdef __GNUC__

244

#pragma GCC diagnostic push

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#pragma GCC diagnostic ignored "-Wcast-qual"

246

#endif

247

free((char *)(new_server->ip));

248

#ifdef __GNUC__

249

#pragma GCC diagnostic pop

250

#endif

251

free(new_server);

252

return false;

207

253

}

208

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/* Special case of first server */

209

if (mc.current_server == NULL){

255

if(*current_server == NULL){

210

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new_server->next = new_server;

211

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new_server->prev = new_server;

212

mc.current_server = new_server;

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

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*current_server = new_server;

214

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} else {

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new_server->next = mc.current_server;

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

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

261

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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mc.current_server->prev = new_server;

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}

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

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if(ret == -1){

222

perror_plus("clock_gettime");

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return -1;

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}

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return 0;

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(*current_server)->prev = new_server;

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}

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return true;

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}

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/*

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* Initialize GPGME.

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*/

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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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__attribute__((nonnull, warn_unused_result))

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static bool init_gpgme(const char * const seckey,

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const char * const pubkey,

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const char * const tempdir,

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mandos_context *mc){

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gpgme_error_t rc;

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gpgme_engine_info_t engine_info;

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279

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/*

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

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282

*/

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bool import_key(const char *filename){

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bool import_key(const char * const filename){

241

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int ret;

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int fd;

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286

gpgme_data_t pgp_data;

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293

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rc = gpgme_data_new_from_fd(&pgp_data, fd);

252

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if(rc != GPG_ERR_NO_ERROR){

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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){

260

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

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gpgme_strsource(rc), gpgme_strerror(rc));

303

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

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gpgme_strsource(rc), gpgme_strerror(rc));

262

305

return false;

263

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}

264

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314

}

272

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273

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if(debug){

274

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

317

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

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}

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319

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/* Init GPGME */

278

321

gpgme_check_version(NULL);

279

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rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

280

323

if(rc != GPG_ERR_NO_ERROR){

281

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

282

gpgme_strsource(rc), gpgme_strerror(rc));

324

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

325

gpgme_strsource(rc), gpgme_strerror(rc));

283

326

return false;

284

327

}

285

328

286

329

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

287

330

rc = gpgme_get_engine_info(&engine_info);

288

331

if(rc != GPG_ERR_NO_ERROR){

289

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

290

gpgme_strsource(rc), gpgme_strerror(rc));

332

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

333

gpgme_strsource(rc), gpgme_strerror(rc));

291

334

return false;

292

335

}

293

336

while(engine_info != NULL){

299

342

engine_info = engine_info->next;

300

343

}

301

344

if(engine_info == NULL){

302

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

345

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

346

tempdir);

303

347

return false;

304

348

}

305

349

306

350

/* Create new GPGME "context" */

307

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

351

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

308

352

if(rc != GPG_ERR_NO_ERROR){

309

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

310

gpgme_strsource(rc), gpgme_strerror(rc));

353

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

354

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

355

gpgme_strerror(rc));

311

356

return false;

312

357

}

313

358

322

367

* Decrypt OpenPGP data.

323

368

* Returns -1 on error

324

369

*/

370

__attribute__((nonnull, warn_unused_result))

325

371

static ssize_t pgp_packet_decrypt(const char *cryptotext,

326

372

size_t crypto_size,

327

char **plaintext){

373

char **plaintext,

374

mandos_context *mc){

328

375

gpgme_data_t dh_crypto, dh_plain;

329

376

gpgme_error_t rc;

330

377

ssize_t ret;

332

379

ssize_t plaintext_length = 0;

333

380

334

381

if(debug){

335

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

382

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

336

383

}

337

384

338

385

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

339

386

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

340

387

0);

341

388

if(rc != GPG_ERR_NO_ERROR){

342

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

343

gpgme_strsource(rc), gpgme_strerror(rc));

389

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

390

gpgme_strsource(rc), gpgme_strerror(rc));

344

391

return -1;

345

392

}

346

393

347

394

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

348

395

rc = gpgme_data_new(&dh_plain);

349

396

if(rc != GPG_ERR_NO_ERROR){

350

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

351

gpgme_strsource(rc), gpgme_strerror(rc));

397

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

398

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

399

gpgme_strsource(rc), gpgme_strerror(rc));

352

400

gpgme_data_release(dh_crypto);

353

401

return -1;

354

402

}

355

403

356

404

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

357

405

data buffer */

358

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

406

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

359

407

if(rc != GPG_ERR_NO_ERROR){

360

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

361

gpgme_strsource(rc), gpgme_strerror(rc));

408

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

409

gpgme_strsource(rc), gpgme_strerror(rc));

362

410

plaintext_length = -1;

363

411

if(debug){

364

412

gpgme_decrypt_result_t result;

365

result = gpgme_op_decrypt_result(mc.ctx);

413

result = gpgme_op_decrypt_result(mc->ctx);

366

414

if(result == NULL){

367

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

415

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

368

416

} else {

369

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

370

result->unsupported_algorithm);

371

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

372

result->wrong_key_usage);

417

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

418

result->unsupported_algorithm);

419

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

420

result->wrong_key_usage);

373

421

if(result->file_name != NULL){

374

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

422

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

375

423

}

376

424

gpgme_recipient_t recipient;

377

425

recipient = result->recipients;

378

426

while(recipient != NULL){

379

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

380

gpgme_pubkey_algo_name(recipient->pubkey_algo));

381

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

382

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

383

recipient->status == GPG_ERR_NO_SECKEY

384

? "No" : "Yes");

427

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

428

gpgme_pubkey_algo_name

429

(recipient->pubkey_algo));

430

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

431

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

432

recipient->status == GPG_ERR_NO_SECKEY

433

? "No" : "Yes");

385

434

recipient = recipient->next;

386

435

}

387

436

}

390

439

}

391

440

392

441

if(debug){

393

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

442

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

394

443

}

395

444

396

445

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

403

452

*plaintext = NULL;

404

453

while(true){

405

454

plaintext_capacity = incbuffer(plaintext,

406

(size_t)plaintext_length,

407

plaintext_capacity);

455

(size_t)plaintext_length,

456

plaintext_capacity);

408

457

if(plaintext_capacity == 0){

409

perror_plus("incbuffer");

410

plaintext_length = -1;

411

goto decrypt_end;

458

perror_plus("incbuffer");

459

plaintext_length = -1;

460

goto decrypt_end;

412

461

}

413

462

414

463

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

427

476

}

428

477

429

478

if(debug){

430

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

479

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

431

480

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

432

481

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

433

482

}

444

493

return plaintext_length;

445

494

}

446

495

447

static const char * safer_gnutls_strerror(int value){

448

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

449

-Wunreachable-code */

496

__attribute__((warn_unused_result))

497

static const char *safer_gnutls_strerror(int value){

498

const char *ret = gnutls_strerror(value);

450

499

if(ret == NULL)

451

500

ret = "(unknown)";

452

501

return ret;

453

502

}

454

503

455

504

/* GnuTLS log function callback */

505

__attribute__((nonnull))

456

506

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

457

507

const char* string){

458

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

508

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

459

509

}

460

510

511

__attribute__((nonnull, warn_unused_result))

461

512

static int init_gnutls_global(const char *pubkeyfilename,

462

const char *seckeyfilename){

513

const char *seckeyfilename,

514

mandos_context *mc){

463

515

int ret;

464

516

465

517

if(debug){

466

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

518

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

467

519

}

468

520

469

521

ret = gnutls_global_init();

470

522

if(ret != GNUTLS_E_SUCCESS){

471

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

472

safer_gnutls_strerror(ret));

523

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

524

safer_gnutls_strerror(ret));

473

525

return -1;

474

526

}

475

527

482

534

}

483

535

484

536

/* OpenPGP credentials */

485

ret = gnutls_certificate_allocate_credentials(&mc.cred);

537

ret = gnutls_certificate_allocate_credentials(&mc->cred);

486

538

if(ret != GNUTLS_E_SUCCESS){

487

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

488

safer_gnutls_strerror(ret));

539

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

540

safer_gnutls_strerror(ret));

489

541

gnutls_global_deinit();

490

542

return -1;

491

543

}

492

544

493

545

if(debug){

494

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

495

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

496

seckeyfilename);

546

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

547

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

548

pubkeyfilename,

549

seckeyfilename);

497

550

}

498

551

499

552

ret = gnutls_certificate_set_openpgp_key_file

500

(mc.cred, pubkeyfilename, seckeyfilename,

553

(mc->cred, pubkeyfilename, seckeyfilename,

501

554

GNUTLS_OPENPGP_FMT_BASE64);

502

555

if(ret != GNUTLS_E_SUCCESS){

503

fprintf(stderr,

504

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

505

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

506

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

507

safer_gnutls_strerror(ret));

556

fprintf_plus(stderr,

557

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

558

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

559

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

560

safer_gnutls_strerror(ret));

508

561

goto globalfail;

509

562

}

510

563

511

564

/* GnuTLS server initialization */

512

ret = gnutls_dh_params_init(&mc.dh_params);

565

ret = gnutls_dh_params_init(&mc->dh_params);

513

566

if(ret != GNUTLS_E_SUCCESS){

514

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

515

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

567

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

568

" initialization: %s\n",

569

safer_gnutls_strerror(ret));

516

570

goto globalfail;

517

571

}

518

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

572

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

519

573

if(ret != GNUTLS_E_SUCCESS){

520

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

521

safer_gnutls_strerror(ret));

574

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

575

safer_gnutls_strerror(ret));

522

576

goto globalfail;

523

577

}

524

578

525

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

579

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

526

580

527

581

return 0;

528

582

529

583

globalfail:

530

584

531

gnutls_certificate_free_credentials(mc.cred);

585

gnutls_certificate_free_credentials(mc->cred);

532

586

gnutls_global_deinit();

533

gnutls_dh_params_deinit(mc.dh_params);

587

gnutls_dh_params_deinit(mc->dh_params);

534

588

return -1;

535

589

}

536

590

537

static int init_gnutls_session(gnutls_session_t *session){

591

__attribute__((nonnull, warn_unused_result))

592

static int init_gnutls_session(gnutls_session_t *session,

593

mandos_context *mc){

538

594

int ret;

539

595

/* GnuTLS session creation */

540

596

do {

544

600

}

545

601

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

546

602

if(ret != GNUTLS_E_SUCCESS){

547

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

548

safer_gnutls_strerror(ret));

603

fprintf_plus(stderr,

604

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

605

safer_gnutls_strerror(ret));

549

606

}

550

607

551

608

{

552

609

const char *err;

553

610

do {

554

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

611

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

555

612

if(quit_now){

556

613

gnutls_deinit(*session);

557

614

return -1;

558

615

}

559

616

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

560

617

if(ret != GNUTLS_E_SUCCESS){

561

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

562

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

563

safer_gnutls_strerror(ret));

618

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

619

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

620

safer_gnutls_strerror(ret));

564

621

gnutls_deinit(*session);

565

622

return -1;

566

623

}

568

625

569

626

do {

570

627

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

571

mc.cred);

628

mc->cred);

572

629

if(quit_now){

573

630

gnutls_deinit(*session);

574

631

return -1;

575

632

}

576

633

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

577

634

if(ret != GNUTLS_E_SUCCESS){

578

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

579

safer_gnutls_strerror(ret));

635

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

636

safer_gnutls_strerror(ret));

580

637

gnutls_deinit(*session);

581

638

return -1;

582

639

}

584

641

/* ignore client certificate if any. */

585

642

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

586

643

587

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

644

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

588

645

589

646

return 0;

590

647

}

593

650

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

594

651

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

595

652

653

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

654

__attribute__((warn_unused_result))

655

error_t raise_privileges(void){

656

error_t old_errno = errno;

657

error_t ret_errno = 0;

658

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

659

ret_errno = errno;

660

}

661

errno = old_errno;

662

return ret_errno;

663

}

664

665

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

666

__attribute__((warn_unused_result))

667

error_t raise_privileges_permanently(void){

668

error_t old_errno = errno;

669

error_t ret_errno = raise_privileges();

670

if(ret_errno != 0){

671

errno = old_errno;

672

return ret_errno;

673

}

674

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

675

ret_errno = errno;

676

}

677

errno = old_errno;

678

return ret_errno;

679

}

680

681

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

682

__attribute__((warn_unused_result))

683

error_t lower_privileges(void){

684

error_t old_errno = errno;

685

error_t ret_errno = 0;

686

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

687

ret_errno = errno;

688

}

689

errno = old_errno;

690

return ret_errno;

691

}

692

693

/* Lower privileges permanently */

694

__attribute__((warn_unused_result))

695

error_t lower_privileges_permanently(void){

696

error_t old_errno = errno;

697

error_t ret_errno = 0;

698

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

699

ret_errno = errno;

700

}

701

errno = old_errno;

702

return ret_errno;

703

}

704

705

/* Helper function to add_local_route() and remove_local_route() */

706

__attribute__((nonnull, warn_unused_result))

707

static bool add_remove_local_route(const bool add,

708

const char *address,

709

AvahiIfIndex if_index){

710

int ret;

711

char helper[] = "mandos-client-iprouteadddel";

712

char add_arg[] = "add";

713

char remove_arg[] = "remove";

714

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

715

if(pluginhelperdir == NULL){

716

if(debug){

717

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

718

" variable not set; cannot run helper\n");

719

}

720

return false;

721

}

722

723

char interface[IF_NAMESIZE];

724

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

725

perror_plus("if_indextoname");

726

return false;

727

}

728

729

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

730

if(devnull == -1){

731

perror_plus("open(\"/dev/null\", O_RDONLY)");

732

return false;

733

}

734

pid_t pid = fork();

735

if(pid == 0){

736

/* Child */

737

/* Raise privileges */

738

errno = raise_privileges_permanently();

739

if(errno != 0){

740

perror_plus("Failed to raise privileges");

741

/* _exit(EX_NOPERM); */

742

} else {

743

/* Set group */

744

errno = 0;

745

ret = setgid(0);

746

if(ret == -1){

747

perror_plus("setgid");

748

_exit(EX_NOPERM);

749

}

750

/* Reset supplementary groups */

751

errno = 0;

752

ret = setgroups(0, NULL);

753

if(ret == -1){

754

perror_plus("setgroups");

755

_exit(EX_NOPERM);

756

}

757

}

758

ret = dup2(devnull, STDIN_FILENO);

759

if(ret == -1){

760

perror_plus("dup2(devnull, STDIN_FILENO)");

761

_exit(EX_OSERR);

762

}

763

ret = close(devnull);

764

if(ret == -1){

765

perror_plus("close");

766

_exit(EX_OSERR);

767

}

768

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

769

if(ret == -1){

770

perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");

771

_exit(EX_OSERR);

772

}

773

int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,

774

O_RDONLY

775

| O_DIRECTORY

776

| O_PATH

777

| O_CLOEXEC));

778

int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,

779

helper, O_RDONLY));

780

TEMP_FAILURE_RETRY(close(helperdir_fd));

781

#ifdef __GNUC__

782

#pragma GCC diagnostic push

783

#pragma GCC diagnostic ignored "-Wcast-qual"

784

#endif

785

if(fexecve(helper_fd, (char *const [])

786

{ helper, add ? add_arg : remove_arg, (char *)address,

787

interface, NULL }, environ) == -1){

788

#ifdef __GNUC__

789

#pragma GCC diagnostic pop

790

#endif

791

perror_plus("fexecve");

792

_exit(EXIT_FAILURE);

793

}

794

}

795

if(pid == -1){

796

perror_plus("fork");

797

return false;

798

}

799

int status;

800

pid_t pret = -1;

801

errno = 0;

802

do {

803

pret = waitpid(pid, &status, 0);

804

if(pret == -1 and errno == EINTR and quit_now){

805

int errno_raising = 0;

806

if((errno = raise_privileges()) != 0){

807

errno_raising = errno;

808

perror_plus("Failed to raise privileges in order to"

809

" kill helper program");

810

}

811

if(kill(pid, SIGTERM) == -1){

812

perror_plus("kill");

813

}

814

if((errno_raising == 0) and (errno = lower_privileges()) != 0){

815

perror_plus("Failed to lower privileges after killing"

816

" helper program");

817

}

818

return false;

819

}

820

} while(pret == -1 and errno == EINTR);

821

if(pret == -1){

822

perror_plus("waitpid");

823

return false;

824

}

825

if(WIFEXITED(status)){

826

if(WEXITSTATUS(status) != 0){

827

fprintf_plus(stderr, "Error: iprouteadddel exited"

828

" with status %d\n", WEXITSTATUS(status));

829

return false;

830

}

831

return true;

832

}

833

if(WIFSIGNALED(status)){

834

fprintf_plus(stderr, "Error: iprouteadddel died by"

835

" signal %d\n", WTERMSIG(status));

836

return false;

837

}

838

fprintf_plus(stderr, "Error: iprouteadddel crashed\n");

839

return false;

840

}

841

842

__attribute__((nonnull, warn_unused_result))

843

static bool add_local_route(const char *address,

844

AvahiIfIndex if_index){

845

return add_remove_local_route(true, address, if_index);

846

}

847

848

__attribute__((nonnull, warn_unused_result))

849

static bool remove_local_route(const char *address,

850

AvahiIfIndex if_index){

851

return add_remove_local_route(false, address, if_index);

852

}

853

596

854

/* Called when a Mandos server is found */

597

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

855

__attribute__((nonnull, warn_unused_result))

856

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

598

857

AvahiIfIndex if_index,

599

int af){

858

int af, mandos_context *mc){

600

859

int ret, tcp_sd = -1;

601

860

ssize_t sret;

602

union {

603

struct sockaddr_in in;

604

struct sockaddr_in6 in6;

605

} to;

861

struct sockaddr_storage to;

606

862

char *buffer = NULL;

607

863

char *decrypted_buffer = NULL;

608

864

size_t buffer_length = 0;

611

867

int retval = -1;

612

868

gnutls_session_t session;

613

869

int pf; /* Protocol family */

870

bool route_added = false;

614

871

615

872

errno = 0;

616

873

627

884

pf = PF_INET;

628

885

break;

629

886

default:

630

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

887

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

631

888

errno = EINVAL;

632

889

return -1;

633

890

}

634

891

635

ret = init_gnutls_session(&session);

892

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

893

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

894

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

895

bool match = false;

896

{

897

char *interface = NULL;

898

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

899

interface))){

900

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

901

match = true;

902

break;

903

}

904

}

905

}

906

if(not match){

907

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

908

connect to the server */

909

if(debug){

910

char interface[IF_NAMESIZE];

911

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

912

perror_plus("if_indextoname");

913

} else {

914

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

915

" \"%s\"\n",

916

if_indextoname((unsigned int)if_index,

917

interface));

918

}

919

}

920

return -1;

921

}

922

}

923

924

ret = init_gnutls_session(&session, mc);

636

925

if(ret != 0){

637

926

return -1;

638

927

}

639

928

640

929

if(debug){

641

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

642

"\n", ip, port);

930

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

931

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

643

932

}

644

933

645

tcp_sd = socket(pf, SOCK_STREAM, 0);

934

tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);

646

935

if(tcp_sd < 0){

647

936

int e = errno;

648

937

perror_plus("socket");

657

946

658

947

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

659

948

if(af == AF_INET6){

660

to.in6.sin6_family = (sa_family_t)af;

661

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

949

((struct sockaddr_in6 *)&to)->sin6_family = (sa_family_t)af;

950

ret = inet_pton(af, ip, &((struct sockaddr_in6 *)&to)->sin6_addr);

662

951

} else { /* IPv4 */

663

to.in.sin_family = (sa_family_t)af;

664

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

952

((struct sockaddr_in *)&to)->sin_family = (sa_family_t)af;

953

ret = inet_pton(af, ip, &((struct sockaddr_in *)&to)->sin_addr);

665

954

}

666

955

if(ret < 0 ){

667

956

int e = errno;

671

960

}

672

961

if(ret == 0){

673

962

int e = errno;

674

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

963

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

675

964

errno = e;

676

965

goto mandos_end;

677

966

}

678

967

if(af == AF_INET6){

679

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

680

-Wconversion and

681

-Wunreachable-code */

682

683

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

684

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

685

-Wunreachable-code*/

968

((struct sockaddr_in6 *)&to)->sin6_port = htons(port);

969

if(IN6_IS_ADDR_LINKLOCAL

970

(&((struct sockaddr_in6 *)&to)->sin6_addr)){

686

971

if(if_index == AVAHI_IF_UNSPEC){

687

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

688

" without a network interface\n");

972

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

973

" incomplete without a network interface\n");

689

974

errno = EINVAL;

690

975

goto mandos_end;

691

976

}

692

977

/* Set the network interface number as scope */

693

to.in6.sin6_scope_id = (uint32_t)if_index;

978

((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;

694

979

}

695

980

} else {

696

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

697

-Wconversion and

698

-Wunreachable-code */

981

((struct sockaddr_in *)&to)->sin_port = htons(port);

699

982

}

700

983

701

984

if(quit_now){

709

992

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

710

993

perror_plus("if_indextoname");

711

994

} else {

712

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

713

ip, interface, port);

995

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

996

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

714

997

}

715

998

} else {

716

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

717

port);

999

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

1000

ip, (uintmax_t)port);

718

1001

}

719

1002

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

720

1003

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

721

const char *pcret;

722

if(af == AF_INET6){

723

pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,

724

sizeof(addrstr));

725

} else {

726

pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,

727

sizeof(addrstr));

728

}

729

if(pcret == NULL){

730

perror_plus("inet_ntop");

731

} else {

732

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

733

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

734

}

735

}

736

}

737

738

if(quit_now){

739

errno = EINTR;

740

goto mandos_end;

741

}

742

743

if(af == AF_INET6){

744

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

745

} else {

746

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

747

}

748

if(ret < 0){

749

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

750

int e = errno;

751

perror_plus("connect");

752

errno = e;

753

}

754

goto mandos_end;

755

}

756

757

if(quit_now){

758

errno = EINTR;

759

goto mandos_end;

1004

if(af == AF_INET6){

1005

ret = getnameinfo((struct sockaddr *)&to,

1006

sizeof(struct sockaddr_in6),

1007

addrstr, sizeof(addrstr), NULL, 0,

1008

NI_NUMERICHOST);

1009

} else {

1010

ret = getnameinfo((struct sockaddr *)&to,

1011

sizeof(struct sockaddr_in),

1012

addrstr, sizeof(addrstr), NULL, 0,

1013

NI_NUMERICHOST);

1014

}

1015

if(ret == EAI_SYSTEM){

1016

perror_plus("getnameinfo");

1017

} else if(ret != 0) {

1018

fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));

1019

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

1020

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

1021

}

1022

}

1023

1024

if(quit_now){

1025

errno = EINTR;

1026

goto mandos_end;

1027

}

1028

1029

while(true){

1030

if(af == AF_INET6){

1031

ret = connect(tcp_sd, (struct sockaddr *)&to,

1032

sizeof(struct sockaddr_in6));

1033

} else {

1034

ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */

1035

sizeof(struct sockaddr_in));

1036

}

1037

if(ret < 0){

1038

if(errno == ENETUNREACH

1039

and if_index != AVAHI_IF_UNSPEC

1040

and connect_to == NULL

1041

and not route_added and

1042

((af == AF_INET6 and not

1043

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1044

&to)->sin6_addr)))

1045

or (af == AF_INET and

1046

/* Not a a IPv4LL address */

1047

(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)

1048

& 0xFFFF0000L) != 0xA9FE0000L))){

1049

/* Work around Avahi bug - Avahi does not announce link-local

1050

addresses if it has a global address, so local hosts with

1051

*only* a link-local address (e.g. Mandos clients) cannot

1052

connect to a Mandos server announced by Avahi on a server

1053

host with a global address. Work around this by retrying

1054

with an explicit route added with the server's address.

1055

1056

Avahi bug reference:

1057

http://lists.freedesktop.org/archives/avahi/2010-February/001833.html

1058

https://bugs.debian.org/587961

1059

*/

1060

int e = errno;

1061

route_added = add_local_route(ip, if_index);

1062

if(route_added){

1063

continue;

1064

}

1065

errno = e;

1066

}

1067

if(errno != ECONNREFUSED or debug){

1068

int e = errno;

1069

perror_plus("connect");

1070

errno = e;

1071

}

1072

goto mandos_end;

1073

}

1074

1075

if(quit_now){

1076

errno = EINTR;

1077

goto mandos_end;

1078

}

1079

break;

760

1080

}

761

1081

762

1082

const char *out = mandos_protocol_version;

764

1084

while(true){

765

1085

size_t out_size = strlen(out);

766

1086

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

767

out_size - written));

1087

out_size - written));

768

1088

if(ret == -1){

769

1089

int e = errno;

770

1090

perror_plus("write");

790

1110

}

791

1111

792

1112

if(debug){

793

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

1113

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

794

1114

}

795

1115

796

1116

if(quit_now){

798

1118

goto mandos_end;

799

1119

}

800

1120

801

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

802

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1121

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

1122

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

1123

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

1124

gnutls_transport_set_ptr(session,

1125

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

803

1126

804

1127

if(quit_now){

805

1128

errno = EINTR;

816

1139

817

1140

if(ret != GNUTLS_E_SUCCESS){

818

1141

if(debug){

819

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

1142

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

820

1143

gnutls_perror(ret);

821

1144

}

822

1145

errno = EPROTO;

826

1149

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

827

1150

828

1151

if(debug){

829

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

830

ip);

1152

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

1153

" %s\n", ip);

831

1154

}

832

1155

833

1156

while(true){

838

1161

}

839

1162

840

1163

buffer_capacity = incbuffer(&buffer, buffer_length,

841

buffer_capacity);

1164

buffer_capacity);

842

1165

if(buffer_capacity == 0){

843

1166

int e = errno;

844

1167

perror_plus("incbuffer");

871

1194

}

872

1195

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

873

1196

if(ret < 0){

874

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

1197

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

1198

"***\n");

875

1199

gnutls_perror(ret);

876

1200

errno = EPROTO;

877

1201

goto mandos_end;

878

1202

}

879

1203

break;

880

1204

default:

881

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

882

" encrypted session with Mandos server\n");

1205

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

1206

" encrypted session with Mandos server\n");

883

1207

gnutls_bye(session, GNUTLS_SHUT_RDWR);

884

1208

errno = EIO;

885

1209

goto mandos_end;

890

1214

}

891

1215

892

1216

if(debug){

893

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

1217

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

894

1218

}

895

1219

896

1220

if(quit_now){

908

1232

909

1233

if(buffer_length > 0){

910

1234

ssize_t decrypted_buffer_size;

911

decrypted_buffer_size = pgp_packet_decrypt(buffer,

912

buffer_length,

913

&decrypted_buffer);

1235

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1236

&decrypted_buffer, mc);

914

1237

if(decrypted_buffer_size >= 0){

915

1238

916

1239

written = 0;

926

1249

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

927

1250

int e = errno;

928

1251

if(debug){

929

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

930

strerror(errno));

1252

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

1253

strerror(errno));

931

1254

}

932

1255

errno = e;

933

1256

goto mandos_end;

942

1265

943

1266

mandos_end:

944

1267

{

1268

if(route_added){

1269

if(not remove_local_route(ip, if_index)){

1270

fprintf_plus(stderr, "Failed to remove local route to %s on"

1271

" interface %d", ip, if_index);

1272

}

1273

}

945

1274

int e = errno;

946

1275

free(decrypted_buffer);

947

1276

free(buffer);

964

1293

return retval;

965

1294

}

966

1295

1296

__attribute__((nonnull))

967

1297

static void resolve_callback(AvahiSServiceResolver *r,

968

1298

AvahiIfIndex interface,

969

1299

AvahiProtocol proto,

977

1307

AVAHI_GCC_UNUSED AvahiStringList *txt,

978

1308

AVAHI_GCC_UNUSED AvahiLookupResultFlags

979

1309

flags,

980

AVAHI_GCC_UNUSED void* userdata){

981

assert(r);

1310

void *mc){

1311

if(r == NULL){

1312

return;

1313

}

982

1314

983

1315

/* Called whenever a service has been resolved successfully or

984

1316

timed out */

985

1317

986

1318

if(quit_now){

1319

avahi_s_service_resolver_free(r);

987

1320

return;

988

1321

}

989

1322

990

1323

switch(event){

991

1324

default:

992

1325

case AVAHI_RESOLVER_FAILURE:

993

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

994

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

995

avahi_strerror(avahi_server_errno(mc.server)));

1326

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

1327

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

1328

domain,

1329

avahi_strerror(avahi_server_errno

1330

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

996

1331

break;

997

1332

998

1333

case AVAHI_RESOLVER_FOUND:

1000

1335

char ip[AVAHI_ADDRESS_STR_MAX];

1001

1336

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

1002

1337

if(debug){

1003

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

1004

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

1005

ip, (intmax_t)interface, port);

1338

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

1339

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

1340

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

1006

1341

}

1007

int ret = start_mandos_communication(ip, port, interface,

1008

avahi_proto_to_af(proto));

1342

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

1343

interface,

1344

avahi_proto_to_af(proto),

1345

mc);

1009

1346

if(ret == 0){

1010

avahi_simple_poll_quit(mc.simple_poll);

1347

avahi_simple_poll_quit(simple_poll);

1011

1348

} else {

1012

ret = add_server(ip, port, interface,

1013

avahi_proto_to_af(proto));

1349

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

1350

avahi_proto_to_af(proto),

1351

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

1352

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

1353

" list\n", name);

1354

}

1014

1355

}

1015

1356

}

1016

1357

}

1026

1367

const char *domain,

1027

1368

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1028

1369

flags,

1029

AVAHI_GCC_UNUSED void* userdata){

1030

assert(b);

1370

void *mc){

1371

if(b == NULL){

1372

return;

1373

}

1031

1374

1032

1375

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

1033

1376

is removed from the LAN */

1040

1383

default:

1041

1384

case AVAHI_BROWSER_FAILURE:

1042

1385

1043

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

1044

avahi_strerror(avahi_server_errno(mc.server)));

1045

avahi_simple_poll_quit(mc.simple_poll);

1386

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

1387

avahi_strerror(avahi_server_errno

1388

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

1389

avahi_simple_poll_quit(simple_poll);

1046

1390

return;

1047

1391

1048

1392

case AVAHI_BROWSER_NEW:

1051

1395

the callback function is called the Avahi server will free the

1052

1396

resolver for us. */

1053

1397

1054

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

1055

name, type, domain, protocol, 0,

1056

resolve_callback, NULL) == NULL)

1057

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

1058

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

1398

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

1399

interface, protocol, name, type,

1400

domain, protocol, 0,

1401

resolve_callback, mc) == NULL)

1402

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

1403

" %s\n", name,

1404

avahi_strerror(avahi_server_errno

1405

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

1059

1406

break;

1060

1407

1061

1408

case AVAHI_BROWSER_REMOVE:

1064

1411

case AVAHI_BROWSER_ALL_FOR_NOW:

1065

1412

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1066

1413

if(debug){

1067

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

1414

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

1415

" searching...\n");

1068

1416

}

1069

1417

break;

1070

1418

}

1079

1427

signal_received = sig;

1080

1428

int old_errno = errno;

1081

1429

/* set main loop to exit */

1082

if(mc.simple_poll != NULL){

1083

avahi_simple_poll_quit(mc.simple_poll);

1430

if(simple_poll != NULL){

1431

avahi_simple_poll_quit(simple_poll);

1084

1432

}

1085

1433

errno = old_errno;

1086

1434

}

1087

1435

1436

__attribute__((nonnull, warn_unused_result))

1437

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

1438

int ret;

1439

error_t ret_errno;

1440

1441

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

1442

if(s < 0){

1443

ret_errno = errno;

1444

perror_plus("socket");

1445

errno = ret_errno;

1446

return false;

1447

}

1448

strcpy(ifr->ifr_name, ifname);

1449

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1450

if(ret == -1){

1451

if(debug){

1452

ret_errno = errno;

1453

perror_plus("ioctl SIOCGIFFLAGS");

1454

errno = ret_errno;

1455

}

1456

return false;

1457

}

1458

return true;

1459

}

1460

1461

__attribute__((nonnull, warn_unused_result))

1462

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

1463

1464

/* Reject the loopback device */

1465

if(ifr->ifr_flags & IFF_LOOPBACK){

1466

if(debug){

1467

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

1468

ifname);

1469

}

1470

return false;

1471

}

1472

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

1473

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

1474

if(debug){

1475

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

1476

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

1477

}

1478

return true;

1479

}

1480

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

1481

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

1482

if(debug){

1483

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1484

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

1485

}

1486

return false;

1487

}

1488

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

1489

if(ifr->ifr_flags & IFF_NOARP){

1490

if(debug){

1491

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

1492

ifname);

1493

}

1494

return false;

1495

}

1496

1497

/* Accept this device */

1498

if(debug){

1499

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

1500

}

1501

return true;

1502

}

1503

1088

1504

/*

1089

1505

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

1090

1506

* corresponds to an acceptable network device.

1091

1507

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

1092

1508

*/

1509

__attribute__((nonnull, warn_unused_result))

1093

1510

int good_interface(const struct dirent *if_entry){

1094

ssize_t ssret;

1095

char *flagname = NULL;

1096

1511

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

1097

1512

return 0;

1098

1513

}

1099

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

1100

if_entry->d_name);

1101

if(ret < 0){

1102

perror_plus("asprintf");

1103

return 0;

1104

}

1105

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

1106

if(flags_fd == -1){

1107

perror_plus("open");

1108

free(flagname);

1109

return 0;

1110

}

1111

free(flagname);

1112

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

1113

/* read line from flags_fd */

1114

ssize_t to_read = 2+(sizeof(ifreq_flags)*2)+1; /* "0x1003\n" */

1115

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

1116

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

1117

if(flagstring == NULL){

1118

perror_plus("malloc");

1119

close(flags_fd);

1120

return 0;

1121

}

1122

while(to_read > 0){

1123

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

1124

(size_t)to_read));

1125

if(ssret == -1){

1126

perror_plus("read");

1127

free(flagstring);

1128

close(flags_fd);

1129

return 0;

1130

}

1131

to_read -= ssret;

1132

if(ssret == 0){

1133

break;

1134

}

1135

}

1136

close(flags_fd);

1137

intmax_t tmpmax;

1138

char *tmp;

1139

errno = 0;

1140

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

1141

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

1142

and not (isspace(*tmp)))

1143

or tmpmax != (ifreq_flags)tmpmax){

1144

if(debug){

1145

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

1146

flagstring, if_entry->d_name);

1147

}

1148

free(flagstring);

1149

return 0;

1150

}

1151

free(flagstring);

1152

ifreq_flags flags = (ifreq_flags)tmpmax;

1153

/* Reject the loopback device */

1154

if(flags & IFF_LOOPBACK){

1155

if(debug){

1156

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

1157

if_entry->d_name);

1158

}

1159

return 0;

1160

}

1161

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

1162

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

1163

if(debug){

1164

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

1165

if_entry->d_name);

1166

}

1167

return 1;

1168

}

1169

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

1170

if(not (flags & IFF_BROADCAST)){

1171

if(debug){

1172

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

1173

if_entry->d_name);

1174

}

1175

return 0;

1176

}

1177

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

1178

if(flags & IFF_NOARP){

1179

if(debug){

1180

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

1181

if_entry->d_name);

1182

}

1183

return 0;

1184

}

1185

/* Accept this device */

1186

if(debug){

1187

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

1188

if_entry->d_name);

1514

1515

struct ifreq ifr;

1516

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

1517

if(debug){

1518

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

1519

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

1520

}

1521

return 0;

1522

}

1523

1524

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

1525

return 0;

1189

1526

}

1190

1527

return 1;

1191

1528

}

1192

1529

1530

/*

1531

* This function determines if a network interface is up.

1532

*/

1533

__attribute__((nonnull, warn_unused_result))

1534

bool interface_is_up(const char *interface){

1535

struct ifreq ifr;

1536

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

1537

if(debug){

1538

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

1539

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

1540

}

1541

return false;

1542

}

1543

1544

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

1545

}

1546

1547

/*

1548

* This function determines if a network interface is running

1549

*/

1550

__attribute__((nonnull, warn_unused_result))

1551

bool interface_is_running(const char *interface){

1552

struct ifreq ifr;

1553

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

1554

if(debug){

1555

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

1556

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

1557

}

1558

return false;

1559

}

1560

1561

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

1562

}

1563

1564

__attribute__((nonnull, pure, warn_unused_result))

1193

1565

int notdotentries(const struct dirent *direntry){

1194

1566

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

1195

1567

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

1201

1573

return 1;

1202

1574

}

1203

1575

1204

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1576

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

1577

__attribute__((nonnull, warn_unused_result))

1578

int runnable_hook(const struct dirent *direntry){

1579

int ret;

1580

size_t sret;

1581

struct stat st;

1582

1583

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

1584

/* Empty name? */

1585

return 0;

1586

}

1587

1588

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

1589

"abcdefghijklmnopqrstuvwxyz"

1590

"0123456789"

1591

"_.-");

1592

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

1593

/* Contains non-allowed characters */

1594

if(debug){

1595

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

1596

direntry->d_name);

1597

}

1598

return 0;

1599

}

1600

1601

ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);

1602

if(ret == -1){

1603

if(debug){

1604

perror_plus("Could not stat hook");

1605

}

1606

return 0;

1607

}

1608

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

1609

/* Not a regular file */

1610

if(debug){

1611

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

1612

direntry->d_name);

1613

}

1614

return 0;

1615

}

1616

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

1617

/* Not executable */

1618

if(debug){

1619

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

1620

direntry->d_name);

1621

}

1622

return 0;

1623

}

1624

if(debug){

1625

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

1626

direntry->d_name);

1627

}

1628

return 1;

1629

}

1630

1631

__attribute__((nonnull, warn_unused_result))

1632

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1633

mandos_context *mc){

1205

1634

int ret;

1206

1635

struct timespec now;

1207

1636

struct timespec waited_time;

1208

1637

intmax_t block_time;

1209

1638

1210

1639

while(true){

1211

if(mc.current_server == NULL){

1212

if (debug){

1213

fprintf(stderr,

1214

"Wait until first server is found. No timeout!\n");

1640

if(mc->current_server == NULL){

1641

if(debug){

1642

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

1643

" No timeout!\n");

1215

1644

}

1216

1645

ret = avahi_simple_poll_iterate(s, -1);

1217

1646

} else {

1218

if (debug){

1219

fprintf(stderr, "Check current_server if we should run it,"

1220

" or wait\n");

1647

if(debug){

1648

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

1649

" it, or wait\n");

1221

1650

}

1222

1651

/* the current time */

1223

1652

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1228

1657

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

1229

1658

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

1230

1659

waited_time.tv_sec = (now.tv_sec

1231

- mc.current_server->last_seen.tv_sec);

1660

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

1232

1661

waited_time.tv_nsec = (now.tv_nsec

1233

- mc.current_server->last_seen.tv_nsec);

1662

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

1234

1663

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

1235

1664

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

1236

1665

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

1238

1667

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

1239

1668

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

1240

1669

1241

if (debug){

1242

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

1670

if(debug){

1671

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

1672

block_time);

1243

1673

}

1244

1674

1245

1675

if(block_time <= 0){

1246

ret = start_mandos_communication(mc.current_server->ip,

1247

mc.current_server->port,

1248

mc.current_server->if_index,

1249

mc.current_server->af);

1676

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

1677

mc->current_server->port,

1678

mc->current_server->if_index,

1679

mc->current_server->af, mc);

1250

1680

if(ret == 0){

1251

avahi_simple_poll_quit(mc.simple_poll);

1681

avahi_simple_poll_quit(s);

1252

1682

return 0;

1253

1683

}

1254

1684

ret = clock_gettime(CLOCK_MONOTONIC,

1255

&mc.current_server->last_seen);

1685

&mc->current_server->last_seen);

1256

1686

if(ret == -1){

1257

1687

perror_plus("clock_gettime");

1258

1688

return -1;

1259

1689

}

1260

mc.current_server = mc.current_server->next;

1690

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

1261

1691

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

1262

1692

servers, but don't block */

1263

1693

}

1265

1695

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

1266

1696

}

1267

1697

if(ret != 0){

1268

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

1698

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

1269

1699

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

1270

1700

}

1271

1701

}

1272

1702

}

1273

1703

}

1274

1704

1705

__attribute__((nonnull))

1706

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

1707

const float delay){

1708

struct dirent **direntries = NULL;

1709

if(hookdir_fd == -1){

1710

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1711

| O_CLOEXEC);

1712

if(hookdir_fd == -1){

1713

if(errno == ENOENT){

1714

if(debug){

1715

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

1716

" found\n", hookdir);

1717

}

1718

} else {

1719

perror_plus("open");

1720

}

1721

return;

1722

}

1723

}

1724

#ifdef __GLIBC__

1725

#if __GLIBC_PREREQ(2, 15)

1726

int numhooks = scandirat(hookdir_fd, ".", &direntries,

1727

runnable_hook, alphasort);

1728

#else /* not __GLIBC_PREREQ(2, 15) */

1729

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

1730

alphasort);

1731

#endif /* not __GLIBC_PREREQ(2, 15) */

1732

#else /* not __GLIBC__ */

1733

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

1734

alphasort);

1735

#endif /* not __GLIBC__ */

1736

if(numhooks == -1){

1737

perror_plus("scandir");

1738

return;

1739

}

1740

struct dirent *direntry;

1741

int ret;

1742

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

1743

if(devnull == -1){

1744

perror_plus("open(\"/dev/null\", O_RDONLY)");

1745

return;

1746

}

1747

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

1748

direntry = direntries[i];

1749

if(debug){

1750

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

1751

direntry->d_name);

1752

}

1753

pid_t hook_pid = fork();

1754

if(hook_pid == 0){

1755

/* Child */

1756

/* Raise privileges */

1757

errno = raise_privileges_permanently();

1758

if(errno != 0){

1759

perror_plus("Failed to raise privileges");

1760

_exit(EX_NOPERM);

1761

}

1762

/* Set group */

1763

errno = 0;

1764

ret = setgid(0);

1765

if(ret == -1){

1766

perror_plus("setgid");

1767

_exit(EX_NOPERM);

1768

}

1769

/* Reset supplementary groups */

1770

errno = 0;

1771

ret = setgroups(0, NULL);

1772

if(ret == -1){

1773

perror_plus("setgroups");

1774

_exit(EX_NOPERM);

1775

}

1776

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

1777

if(ret == -1){

1778

perror_plus("setenv");

1779

_exit(EX_OSERR);

1780

}

1781

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

1782

if(ret == -1){

1783

perror_plus("setenv");

1784

_exit(EX_OSERR);

1785

}

1786

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

1787

if(ret == -1){

1788

perror_plus("setenv");

1789

_exit(EX_OSERR);

1790

}

1791

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

1792

if(ret == -1){

1793

perror_plus("setenv");

1794

_exit(EX_OSERR);

1795

}

1796

char *delaystring;

1797

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

1798

if(ret == -1){

1799

perror_plus("asprintf");

1800

_exit(EX_OSERR);

1801

}

1802

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

1803

if(ret == -1){

1804

free(delaystring);

1805

perror_plus("setenv");

1806

_exit(EX_OSERR);

1807

}

1808

free(delaystring);

1809

if(connect_to != NULL){

1810

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

1811

if(ret == -1){

1812

perror_plus("setenv");

1813

_exit(EX_OSERR);

1814

}

1815

}

1816

int hook_fd = TEMP_FAILURE_RETRY(openat(hookdir_fd,

1817

direntry->d_name,

1818

O_RDONLY));

1819

if(hook_fd == -1){

1820

perror_plus("openat");

1821

_exit(EXIT_FAILURE);

1822

}

1823

if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){

1824

perror_plus("close");

1825

_exit(EXIT_FAILURE);

1826

}

1827

ret = dup2(devnull, STDIN_FILENO);

1828

if(ret == -1){

1829

perror_plus("dup2(devnull, STDIN_FILENO)");

1830

_exit(EX_OSERR);

1831

}

1832

ret = close(devnull);

1833

if(ret == -1){

1834

perror_plus("close");

1835

_exit(EX_OSERR);

1836

}

1837

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1838

if(ret == -1){

1839

perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");

1840

_exit(EX_OSERR);

1841

}

1842

if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },

1843

environ) == -1){

1844

perror_plus("fexecve");

1845

_exit(EXIT_FAILURE);

1846

}

1847

} else {

1848

if(hook_pid == -1){

1849

perror_plus("fork");

1850

free(direntry);

1851

continue;

1852

}

1853

int status;

1854

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

1855

perror_plus("waitpid");

1856

free(direntry);

1857

continue;

1858

}

1859

if(WIFEXITED(status)){

1860

if(WEXITSTATUS(status) != 0){

1861

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

1862

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

1863

WEXITSTATUS(status));

1864

free(direntry);

1865

continue;

1866

}

1867

} else if(WIFSIGNALED(status)){

1868

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

1869

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

1870

WTERMSIG(status));

1871

free(direntry);

1872

continue;

1873

} else {

1874

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

1875

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

1876

free(direntry);

1877

continue;

1878

}

1879

}

1880

if(debug){

1881

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

1882

direntry->d_name);

1883

}

1884

free(direntry);

1885

}

1886

free(direntries);

1887

if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){

1888

perror_plus("close");

1889

} else {

1890

hookdir_fd = -1;

1891

}

1892

close(devnull);

1893

}

1894

1895

__attribute__((nonnull, warn_unused_result))

1896

error_t bring_up_interface(const char *const interface,

1897

const float delay){

1898

error_t old_errno = errno;

1899

int ret;

1900

struct ifreq network;

1901

unsigned int if_index = if_nametoindex(interface);

1902

if(if_index == 0){

1903

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

1904

errno = old_errno;

1905

return ENXIO;

1906

}

1907

1908

if(quit_now){

1909

errno = old_errno;

1910

return EINTR;

1911

}

1912

1913

if(not interface_is_up(interface)){

1914

error_t ret_errno = 0, ioctl_errno = 0;

1915

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

1916

ret_errno = errno;

1917

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

1918

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

1919

errno = old_errno;

1920

return ret_errno;

1921

}

1922

network.ifr_flags |= IFF_UP; /* set flag */

1923

1924

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

1925

if(sd == -1){

1926

ret_errno = errno;

1927

perror_plus("socket");

1928

errno = old_errno;

1929

return ret_errno;

1930

}

1931

1932

if(quit_now){

1933

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

1934

if(ret == -1){

1935

perror_plus("close");

1936

}

1937

errno = old_errno;

1938

return EINTR;

1939

}

1940

1941

if(debug){

1942

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

1943

interface);

1944

}

1945

1946

/* Raise privileges */

1947

ret_errno = raise_privileges();

1948

if(ret_errno != 0){

1949

errno = ret_errno;

1950

perror_plus("Failed to raise privileges");

1951

}

1952

1953

#ifdef __linux__

1954

int ret_linux;

1955

bool restore_loglevel = false;

1956

if(ret_errno == 0){

1957

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1958

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

1959

ret_linux = klogctl(8, NULL, 5);

1960

if(ret_linux == -1){

1961

perror_plus("klogctl");

1962

} else {

1963

restore_loglevel = true;

1964

}

1965

}

1966

#endif /* __linux__ */

1967

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

1968

ioctl_errno = errno;

1969

#ifdef __linux__

1970

if(restore_loglevel){

1971

ret_linux = klogctl(7, NULL, 0);

1972

if(ret_linux == -1){

1973

perror_plus("klogctl");

1974

}

1975

}

1976

#endif /* __linux__ */

1977

1978

/* If raise_privileges() succeeded above */

1979

if(ret_errno == 0){

1980

/* Lower privileges */

1981

ret_errno = lower_privileges();

1982

if(ret_errno != 0){

1983

errno = ret_errno;

1984

perror_plus("Failed to lower privileges");

1985

}

1986

}

1987

1988

/* Close the socket */

1989

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

1990

if(ret == -1){

1991

perror_plus("close");

1992

}

1993

1994

if(ret_setflags == -1){

1995

errno = ioctl_errno;

1996

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1997

errno = old_errno;

1998

return ioctl_errno;

1999

}

2000

} else if(debug){

2001

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

2002

interface);

2003

}

2004

2005

/* Sleep checking until interface is running.

2006

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

2007

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

2008

if(interface_is_running(interface)){

2009

break;

2010

}

2011

struct timespec sleeptime = { .tv_nsec = 250000000 };

2012

ret = nanosleep(&sleeptime, NULL);

2013

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

2014

perror_plus("nanosleep");

2015

}

2016

}

2017

2018

errno = old_errno;

2019

return 0;

2020

}

2021

2022

__attribute__((nonnull, warn_unused_result))

2023

error_t take_down_interface(const char *const interface){

2024

error_t old_errno = errno;

2025

struct ifreq network;

2026

unsigned int if_index = if_nametoindex(interface);

2027

if(if_index == 0){

2028

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

2029

errno = old_errno;

2030

return ENXIO;

2031

}

2032

if(interface_is_up(interface)){

2033

error_t ret_errno = 0, ioctl_errno = 0;

2034

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

2035

ret_errno = errno;

2036

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

2037

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

2038

errno = old_errno;

2039

return ret_errno;

2040

}

2041

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

2042

2043

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

2044

if(sd == -1){

2045

ret_errno = errno;

2046

perror_plus("socket");

2047

errno = old_errno;

2048

return ret_errno;

2049

}

2050

2051

if(debug){

2052

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

2053

interface);

2054

}

2055

2056

/* Raise privileges */

2057

ret_errno = raise_privileges();

2058

if(ret_errno != 0){

2059

errno = ret_errno;

2060

perror_plus("Failed to raise privileges");

2061

}

2062

2063

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

2064

ioctl_errno = errno;

2065

2066

/* If raise_privileges() succeeded above */

2067

if(ret_errno == 0){

2068

/* Lower privileges */

2069

ret_errno = lower_privileges();

2070

if(ret_errno != 0){

2071

errno = ret_errno;

2072

perror_plus("Failed to lower privileges");

2073

}

2074

}

2075

2076

/* Close the socket */

2077

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

2078

if(ret == -1){

2079

perror_plus("close");

2080

}

2081

2082

if(ret_setflags == -1){

2083

errno = ioctl_errno;

2084

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2085

errno = old_errno;

2086

return ioctl_errno;

2087

}

2088

} else if(debug){

2089

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

2090

interface);

2091

}

2092

2093

errno = old_errno;

2094

return 0;

2095

}

2096

1275

2097

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

2098

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

2099

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

2100

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

2101

.interfaces = NULL, .interfaces_size = 0 };

1276

2102

AvahiSServiceBrowser *sb = NULL;

1277

int error;

2103

error_t ret_errno;

1278

2104

int ret;

1279

2105

intmax_t tmpmax;

1280

2106

char *tmp;

1281

2107

int exitcode = EXIT_SUCCESS;

1282

const char *interface = "";

1283

struct ifreq network;

1284

int sd = -1;

1285

bool take_down_interface = false;

1286

uid_t uid;

1287

gid_t gid;

1288

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

1289

bool tempdir_created = false;

2108

char *interfaces_to_take_down = NULL;

2109

size_t interfaces_to_take_down_size = 0;

2110

char run_tempdir[] = "/run/tmp/mandosXXXXXX";

2111

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

2112

char *tempdir = NULL;

1290

2113

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1291

2114

const char *seckey = PATHDIR "/" SECKEY;

1292

2115

const char *pubkey = PATHDIR "/" PUBKEY;

2116

char *interfaces_hooks = NULL;

1293

2117

1294

2118

bool gnutls_initialized = false;

1295

2119

bool gpgme_initialized = false;

1357

2181

.group = 2 },

1358

2182

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

1359

2183

.arg = "SECONDS",

1360

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

2184

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

2185

.group = 2 },

2186

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

2187

.arg = "DIR",

2188

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

1361

2189

.group = 2 },

1362

2190

/*

1363

2191

* These reproduce what we would get without ARGP_NO_HELP

1382

2210

connect_to = arg;

1383

2211

break;

1384

2212

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

1385

interface = arg;

2213

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

2214

arg, (int)',');

2215

if(ret_errno != 0){

2216

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

2217

}

1386

2218

break;

1387

2219

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

1388

2220

seckey = arg;

1417

2249

argp_error(state, "Bad retry interval");

1418

2250

}

1419

2251

break;

2252

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

2253

hookdir = arg;

2254

break;

1420

2255

/*

1421

2256

* These reproduce what we would get without ARGP_NO_HELP

1422

2257

*/

1428

2263

argp_state_help(state, state->out_stream,

1429

2264

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1430

2265

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

1431

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

2266

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

1432

2267

exit(argp_err_exit_status);

1433

2268

break;

1434

2269

default:

1457

2292

goto end;

1458

2293

}

1459

2294

}

1460

2295

1461

2296

{

1462

2297

/* Work around Debian bug #633582:

1463

2298

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

1464

struct stat st;

1465

1466

/* Re-raise priviliges */

1467

errno = 0;

1468

ret = seteuid(0);

1469

if(ret == -1){

1470

perror_plus("seteuid");

1471

}

1472

1473

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

1474

int seckey_fd = open(seckey, O_RDONLY);

1475

if(seckey_fd == -1){

1476

perror_plus("open");

1477

} else {

1478

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

1479

if(ret == -1){

1480

perror_plus("fstat");

1481

} else {

1482

if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){

1483

ret = fchown(seckey_fd, uid, gid);

1484

if(ret == -1){

1485

perror_plus("fchown");

1486

}

1487

}

1488

}

1489

TEMP_FAILURE_RETRY(close(seckey_fd));

1490

}

1491

}

1492

1493

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

1494

int pubkey_fd = open(pubkey, O_RDONLY);

1495

if(pubkey_fd == -1){

1496

perror_plus("open");

1497

} else {

1498

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

1499

if(ret == -1){

1500

perror_plus("fstat");

1501

} else {

1502

if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){

1503

ret = fchown(pubkey_fd, uid, gid);

1504

if(ret == -1){

1505

perror_plus("fchown");

1506

}

1507

}

1508

}

1509

TEMP_FAILURE_RETRY(close(pubkey_fd));

1510

}

1511

}

1512

1513

/* Lower privileges */

1514

errno = 0;

1515

ret = seteuid(uid);

1516

if(ret == -1){

1517

perror_plus("seteuid");

1518

}

2299

2300

/* Re-raise privileges */

2301

ret_errno = raise_privileges();

2302

if(ret_errno != 0){

2303

errno = ret_errno;

2304

perror_plus("Failed to raise privileges");

2305

} else {

2306

struct stat st;

2307

2308

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

2309

int seckey_fd = open(seckey, O_RDONLY);

2310

if(seckey_fd == -1){

2311

perror_plus("open");

2312

} else {

2313

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

2314

if(ret == -1){

2315

perror_plus("fstat");

2316

} else {

2317

if(S_ISREG(st.st_mode)

2318

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

2319

ret = fchown(seckey_fd, uid, gid);

2320

if(ret == -1){

2321

perror_plus("fchown");

2322

}

2323

}

2324

}

2325

TEMP_FAILURE_RETRY(close(seckey_fd));

2326

}

2327

}

2328

2329

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

2330

int pubkey_fd = open(pubkey, O_RDONLY);

2331

if(pubkey_fd == -1){

2332

perror_plus("open");

2333

} else {

2334

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

2335

if(ret == -1){

2336

perror_plus("fstat");

2337

} else {

2338

if(S_ISREG(st.st_mode)

2339

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

2340

ret = fchown(pubkey_fd, uid, gid);

2341

if(ret == -1){

2342

perror_plus("fchown");

2343

}

2344

}

2345

}

2346

TEMP_FAILURE_RETRY(close(pubkey_fd));

2347

}

2348

}

2349

2350

/* Lower privileges */

2351

ret_errno = lower_privileges();

2352

if(ret_errno != 0){

2353

errno = ret_errno;

2354

perror_plus("Failed to lower privileges");

2355

}

2356

}

2357

}

2358

2359

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

2360

{

2361

char *interface = NULL;

2362

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

2363

interface))){

2364

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

2365

and if_nametoindex(interface) == 0){

2366

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

2367

fprintf_plus(stderr, "Not using nonexisting interface"

2368

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

2369

}

2370

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

2371

interface = NULL;

2372

}

2373

}

2374

}

2375

2376

/* Run network hooks */

2377

{

2378

if(mc.interfaces != NULL){

2379

interfaces_hooks = malloc(mc.interfaces_size);

2380

if(interfaces_hooks == NULL){

2381

perror_plus("malloc");

2382

goto end;

2383

}

2384

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

2385

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

2386

}

2387

run_network_hooks("start", interfaces_hooks != NULL ?

2388

interfaces_hooks : "", delay);

1519

2389

}

1520

2390

1521

2391

if(not debug){

1522

2392

avahi_set_log_function(empty_log);

1523

2393

}

1524

1525

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

1526

struct dirent **direntries;

1527

ret = scandir(sys_class_net, &direntries, good_interface,

1528

alphasort);

1529

if(ret >= 1){

1530

/* Pick the first good interface */

1531

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

1532

if(debug){

1533

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

1534

}

1535

if(interface == NULL){

1536

perror_plus("malloc");

1537

free(direntries);

1538

exitcode = EXIT_FAILURE;

1539

goto end;

1540

}

1541

free(direntries);

1542

} else {

1543

free(direntries);

1544

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

1545

exitcode = EXIT_FAILURE;

1546

goto end;

1547

}

1548

}

1549

2394

1550

2395

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

1551

2396

from the signal handler */

1552

2397

/* Initialize the pseudo-RNG for Avahi */

1553

2398

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

1554

mc.simple_poll = avahi_simple_poll_new();

1555

if(mc.simple_poll == NULL){

1556

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

2399

simple_poll = avahi_simple_poll_new();

2400

if(simple_poll == NULL){

2401

fprintf_plus(stderr,

2402

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

1557

2403

exitcode = EX_UNAVAILABLE;

1558

2404

goto end;

1559

2405

}

1621

2467

}

1622

2468

}

1623

2469

1624

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

1625

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

1626

if_index = (AvahiIfIndex) if_nametoindex(interface);

1627

if(if_index == 0){

1628

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

1629

exitcode = EX_UNAVAILABLE;

1630

goto end;

1631

}

1632

1633

if(quit_now){

1634

goto end;

1635

}

1636

1637

/* Re-raise priviliges */

1638

errno = 0;

1639

ret = seteuid(0);

1640

if(ret == -1){

1641

perror_plus("seteuid");

1642

}

1643

1644

#ifdef __linux__

1645

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1646

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

1647

ret = klogctl(8, NULL, 5);

1648

bool restore_loglevel = true;

1649

if(ret == -1){

1650

restore_loglevel = false;

1651

perror_plus("klogctl");

1652

}

1653

#endif /* __linux__ */

1654

1655

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1656

if(sd < 0){

1657

perror_plus("socket");

1658

exitcode = EX_OSERR;

1659

#ifdef __linux__

1660

if(restore_loglevel){

1661

ret = klogctl(7, NULL, 0);

1662

if(ret == -1){

1663

perror_plus("klogctl");

1664

}

1665

}

1666

#endif /* __linux__ */

1667

/* Lower privileges */

1668

errno = 0;

1669

ret = seteuid(uid);

1670

if(ret == -1){

1671

perror_plus("seteuid");

1672

}

1673

goto end;

1674

}

1675

strcpy(network.ifr_name, interface);

1676

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

1677

if(ret == -1){

1678

perror_plus("ioctl SIOCGIFFLAGS");

1679

#ifdef __linux__

1680

if(restore_loglevel){

1681

ret = klogctl(7, NULL, 0);

1682

if(ret == -1){

1683

perror_plus("klogctl");

1684

}

1685

}

1686

#endif /* __linux__ */

1687

exitcode = EX_OSERR;

1688

/* Lower privileges */

1689

errno = 0;

1690

ret = seteuid(uid);

1691

if(ret == -1){

1692

perror_plus("seteuid");

1693

}

1694

goto end;

1695

}

1696

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

1697

network.ifr_flags |= IFF_UP;

1698

take_down_interface = true;

1699

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

1700

if(ret == -1){

1701

take_down_interface = false;

1702

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1703

exitcode = EX_OSERR;

1704

#ifdef __linux__

1705

if(restore_loglevel){

1706

ret = klogctl(7, NULL, 0);

1707

if(ret == -1){

1708

perror_plus("klogctl");

2470

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

2471

if(mc.interfaces == NULL){

2472

struct dirent **direntries = NULL;

2473

/* Look for any good interfaces */

2474

ret = scandir(sys_class_net, &direntries, good_interface,

2475

alphasort);

2476

if(ret >= 1){

2477

/* Add all found interfaces to interfaces list */

2478

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

2479

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

2480

direntries[i]->d_name);

2481

if(ret_errno != 0){

2482

errno = ret_errno;

2483

perror_plus("argz_add");

2484

free(direntries[i]);

2485

continue;

2486

}

2487

if(debug){

2488

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

2489

direntries[i]->d_name);

2490

}

2491

free(direntries[i]);

2492

}

2493

free(direntries);

2494

} else {

2495

if(ret == 0){

2496

free(direntries);

2497

}

2498

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

2499

exitcode = EXIT_FAILURE;

2500

goto end;

2501

}

2502

}

2503

2504

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

2505

{

2506

char *interface = NULL;

2507

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

2508

interface))){

2509

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

2510

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

2511

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

2512

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

2513

interface);

2514

interface = NULL;

2515

while((interface = argz_next(mc.interfaces,

2516

mc.interfaces_size, interface))){

2517

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

2518

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

2519

interface);

2520

interface = NULL;

1709

2521

}

1710

2522

}

1711

#endif /* __linux__ */

1712

/* Lower privileges */

1713

errno = 0;

1714

ret = seteuid(uid);

1715

if(ret == -1){

1716

perror_plus("seteuid");

1717

}

1718

goto end;

1719

}

1720

}

1721

/* Sleep checking until interface is running.

1722

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

1723

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

1724

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

1725

if(ret == -1){

1726

perror_plus("ioctl SIOCGIFFLAGS");

1727

} else if(network.ifr_flags & IFF_RUNNING){

1728

2523

break;

1729

2524

}

1730

struct timespec sleeptime = { .tv_nsec = 250000000 };

1731

ret = nanosleep(&sleeptime, NULL);

1732

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

1733

perror_plus("nanosleep");

1734

}

1735

}

1736

if(not take_down_interface){

1737

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

1738

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

1739

if(ret == -1){

1740

perror_plus("close");

1741

}

1742

}

1743

#ifdef __linux__

1744

if(restore_loglevel){

1745

/* Restores kernel loglevel to default */

1746

ret = klogctl(7, NULL, 0);

1747

if(ret == -1){

1748

perror_plus("klogctl");

1749

}

1750

}

1751

#endif /* __linux__ */

1752

/* Lower privileges */

1753

errno = 0;

1754

if(take_down_interface){

1755

/* Lower privileges */

1756

ret = seteuid(uid);

1757

if(ret == -1){

1758

perror_plus("seteuid");

1759

}

1760

} else {

1761

/* Lower privileges permanently */

1762

ret = setuid(uid);

1763

if(ret == -1){

1764

perror_plus("setuid");

1765

}

1766

}

2525

bool interface_was_up = interface_is_up(interface);

2526

errno = bring_up_interface(interface, delay);

2527

if(not interface_was_up){

2528

if(errno != 0){

2529

perror_plus("Failed to bring up interface");

2530

} else {

2531

errno = argz_add(&interfaces_to_take_down,

2532

&interfaces_to_take_down_size,

2533

interface);

2534

if(errno != 0){

2535

perror_plus("argz_add");

2536

}

2537

}

2538

}

2539

}

2540

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

2541

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

2542

}

2543

}

2544

2545

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

2546

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

2547

if(debug){

2548

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

2549

mc.interfaces);

2550

}

2551

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

1767

2552

}

1768

2553

1769

2554

if(quit_now){

1770

2555

goto end;

1771

2556

}

1772

2557

1773

ret = init_gnutls_global(pubkey, seckey);

2558

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

1774

2559

if(ret == -1){

1775

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

2560

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

1776

2561

exitcode = EX_UNAVAILABLE;

1777

2562

goto end;

1778

2563

} else {

1783

2568

goto end;

1784

2569

}

1785

2570

1786

if(mkdtemp(tempdir) == NULL){

2571

/* Try /run/tmp before /tmp */

2572

tempdir = mkdtemp(run_tempdir);

2573

if(tempdir == NULL and errno == ENOENT){

2574

if(debug){

2575

fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",

2576

run_tempdir, old_tempdir);

2577

}

2578

tempdir = mkdtemp(old_tempdir);

2579

}

2580

if(tempdir == NULL){

1787

2581

perror_plus("mkdtemp");

1788

2582

goto end;

1789

2583

}

1790

tempdir_created = true;

1791

2584

1792

2585

if(quit_now){

1793

2586

goto end;

1794

2587

}

1795

2588

1796

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

1797

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

2589

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

2590

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

1798

2591

exitcode = EX_UNAVAILABLE;

1799

2592

goto end;

1800

2593

} else {

1809

2602

/* Connect directly, do not use Zeroconf */

1810

2603

/* (Mainly meant for debugging) */

1811

2604

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

2605

1812

2606

if(address == NULL){

1813

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

2607

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

1814

2608

exitcode = EX_USAGE;

1815

2609

goto end;

1816

2610

}

1819

2613

goto end;

1820

2614

}

1821

2615

1822

uint16_t port;

2616

in_port_t port;

1823

2617

errno = 0;

1824

2618

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

1825

2619

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

1826

or tmpmax != (uint16_t)tmpmax){

1827

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

2620

or tmpmax != (in_port_t)tmpmax){

2621

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

1828

2622

exitcode = EX_USAGE;

1829

2623

goto end;

1830

2624

}

1831

2625

1832

2626

if(quit_now){

1833

2627

goto end;

1834

2628

}

1835

2629

1836

port = (uint16_t)tmpmax;

2630

port = (in_port_t)tmpmax;

1837

2631

*address = '\0';

1838

2632

/* Colon in address indicates IPv6 */

1839

2633

int af;

1855

2649

}

1856

2650

1857

2651

while(not quit_now){

1858

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

2652

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

2653

&mc);

1859

2654

if(quit_now or ret == 0){

1860

2655

break;

1861

2656

}

1862

2657

if(debug){

1863

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

1864

(int)retry_interval);

2658

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

2659

(int)retry_interval);

1865

2660

}

1866

sleep((int)retry_interval);

2661

sleep((unsigned int)retry_interval);

1867

2662

}

1868

2663

1869

if (not quit_now){

2664

if(not quit_now){

1870

2665

exitcode = EXIT_SUCCESS;

1871

2666

}

1872

2667

1873

2668

goto end;

1874

2669

}

1875

2670

1887

2682

config.publish_domain = 0;

1888

2683

1889

2684

/* Allocate a new server */

1890

mc.server = avahi_server_new(avahi_simple_poll_get

1891

(mc.simple_poll), &config, NULL,

1892

NULL, &error);

2685

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2686

&config, NULL, NULL, &ret_errno);

1893

2687

1894

2688

/* Free the Avahi configuration data */

1895

2689

avahi_server_config_free(&config);

1897

2691

1898

2692

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

1899

2693

if(mc.server == NULL){

1900

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

1901

avahi_strerror(error));

2694

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

2695

avahi_strerror(ret_errno));

1902

2696

exitcode = EX_UNAVAILABLE;

1903

2697

goto end;

1904

2698

}

1910

2704

/* Create the Avahi service browser */

1911

2705

sb = avahi_s_service_browser_new(mc.server, if_index,

1912

2706

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1913

NULL, 0, browse_callback, NULL);

2707

NULL, 0, browse_callback,

2708

(void *)&mc);

1914

2709

if(sb == NULL){

1915

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

1916

avahi_strerror(avahi_server_errno(mc.server)));

2710

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

2711

avahi_strerror(avahi_server_errno(mc.server)));

1917

2712

exitcode = EX_UNAVAILABLE;

1918

2713

goto end;

1919

2714

}

1925

2720

/* Run the main loop */

1926

2721

1927

2722

if(debug){

1928

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

2723

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

1929

2724

}

1930

1931

ret = avahi_loop_with_timeout(mc.simple_poll,

1932

(int)(retry_interval * 1000));

2725

2726

ret = avahi_loop_with_timeout(simple_poll,

2727

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

1933

2728

if(debug){

1934

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

1935

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

2729

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

2730

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

1936

2731

}

1937

2732

1938

2733

end:

1939

2734

1940

2735

if(debug){

1941

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

2736

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

1942

2737

}

1943

2738

1944

2739

/* Cleanup things */

2740

free(mc.interfaces);

2741

1945

2742

if(sb != NULL)

1946

2743

avahi_s_service_browser_free(sb);

1947

2744

1948

2745

if(mc.server != NULL)

1949

2746

avahi_server_free(mc.server);

1950

2747

1951

if(mc.simple_poll != NULL)

1952

avahi_simple_poll_free(mc.simple_poll);

2748

if(simple_poll != NULL)

2749

avahi_simple_poll_free(simple_poll);

1953

2750

1954

2751

if(gnutls_initialized){

1955

2752

gnutls_certificate_free_credentials(mc.cred);

1960

2757

if(gpgme_initialized){

1961

2758

gpgme_release(mc.ctx);

1962

2759

}

1963

2760

1964

2761

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

1965

2762

has seen */

1966

2763

if(mc.current_server != NULL){

1967

2764

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

1968

2765

while(mc.current_server != NULL){

1969

2766

server *next = mc.current_server->next;

2767

#ifdef __GNUC__

2768

#pragma GCC diagnostic push

2769

#pragma GCC diagnostic ignored "-Wcast-qual"

2770

#endif

2771

free((char *)(mc.current_server->ip));

2772

#ifdef __GNUC__

2773

#pragma GCC diagnostic pop

2774

#endif

1970

2775

free(mc.current_server);

1971

2776

mc.current_server = next;

1972

2777

}

1973

2778

}

1974

2779

1975

/* Take down the network interface */

1976

if(take_down_interface){

1977

/* Re-raise priviliges */

1978

errno = 0;

1979

ret = seteuid(0);

1980

if(ret == -1){

1981

perror_plus("seteuid");

2780

/* Re-raise privileges */

2781

{

2782

ret_errno = raise_privileges();

2783

if(ret_errno != 0){

2784

errno = ret_errno;

2785

perror_plus("Failed to raise privileges");

2786

} else {

2787

2788

/* Run network hooks */

2789

run_network_hooks("stop", interfaces_hooks != NULL ?

2790

interfaces_hooks : "", delay);

2791

2792

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

2793

{

2794

char *interface = NULL;

2795

while((interface=argz_next(interfaces_to_take_down,

2796

interfaces_to_take_down_size,

2797

interface))){

2798

ret_errno = take_down_interface(interface);

2799

if(ret_errno != 0){

2800

errno = ret_errno;

2801

perror_plus("Failed to take down interface");

2802

}

2803

}

2804

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

2805

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

2806

" down\n");

2807

}

2808

}

1982

2809

}

1983

if(geteuid() == 0){

1984

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

1985

if(ret == -1){

1986

perror_plus("ioctl SIOCGIFFLAGS");

1987

} else if(network.ifr_flags & IFF_UP) {

1988

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

1989

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

1990

if(ret == -1){

1991

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1992

}

1993

}

1994

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

1995

if(ret == -1){

1996

perror_plus("close");

1997

}

1998

/* Lower privileges permanently */

1999

errno = 0;

2000

ret = setuid(uid);

2001

if(ret == -1){

2002

perror_plus("setuid");

2003

}

2810

2811

ret_errno = lower_privileges_permanently();

2812

if(ret_errno != 0){

2813

errno = ret_errno;

2814

perror_plus("Failed to lower privileges permanently");

2004

2815

}

2005

2816

}

2006

2817

2818

free(interfaces_to_take_down);

2819

free(interfaces_hooks);

2820

2007

2821

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

2008

if(tempdir_created){

2822

if(tempdir != NULL){

2009

2823

struct dirent **direntries = NULL;

2010

struct dirent *direntry = NULL;

2011

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

2012

alphasort);

2013

if (numentries > 0){

2014

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

2015

direntry = direntries[i];

2016

char *fullname = NULL;

2017

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

2018

direntry->d_name);

2019

if(ret < 0){

2020

perror_plus("asprintf");

2021

continue;

2022

}

2023

ret = remove(fullname);

2024

if(ret == -1){

2025

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

2026

strerror(errno));

2027

}

2028

free(fullname);

2824

int tempdir_fd = (int)TEMP_FAILURE_RETRY(open(tempdir, O_RDONLY

2825

| O_NOFOLLOW

2826

| O_DIRECTORY

2827

| O_PATH));

2828

if(tempdir_fd == -1){

2829

perror_plus("open");

2830

} else {

2831

#ifdef __GLIBC__

2832

#if __GLIBC_PREREQ(2, 15)

2833

int numentries = scandirat(tempdir_fd, ".", &direntries,

2834

notdotentries, alphasort);

2835

#else /* not __GLIBC_PREREQ(2, 15) */

2836

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

2837

alphasort);

2838

#endif /* not __GLIBC_PREREQ(2, 15) */

2839

#else /* not __GLIBC__ */

2840

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

2841

alphasort);

2842

#endif /* not __GLIBC__ */

2843

if(numentries >= 0){

2844

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

2845

ret = unlinkat(tempdir_fd, direntries[i]->d_name, 0);

2846

if(ret == -1){

2847

fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"

2848

" \"%s\", 0): %s\n", tempdir,

2849

direntries[i]->d_name, strerror(errno));

2850

}

2851

free(direntries[i]);

2852

}

2853

2854

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

2855

free(direntries);

2856

if(numentries == -1){

2857

perror_plus("scandir");

2858

}

2859

ret = rmdir(tempdir);

2860

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

2861

perror_plus("rmdir");

2862

}

2029

2863

}

2030

}

2031

2032

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

2033

free(direntries);

2034

if (numentries == -1){

2035

perror_plus("scandir");

2036

}

2037

ret = rmdir(tempdir);

2038

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

2039

perror_plus("rmdir");

2864

TEMP_FAILURE_RETRY(close(tempdir_fd));

2040

2865

}

2041

2866

}

2042

2867