/mandos/trunk : revision 237.4.20

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

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*

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* Everything else is

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*

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

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

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

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stdout, ferror(), remove() */

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

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

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

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

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

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

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inet_pton(), connect(),

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getnameinfo() */

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inet_pton(), connect() */

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

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

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*/

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#include <inttypes.h> /* PRIu16, 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(), _exit() */

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

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setgid(), pause() */

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

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

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

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argp_state, struct argp,

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raise() */

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

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EX_NOHOST, EX_IOERR, EX_PROTOCOL */

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

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WEXITSTATUS(), WTERMSIG() */

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

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

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argz_delete(), argz_append(),

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argz_stringify(), argz_add(),

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argz_count() */

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#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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#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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bool debug = false;

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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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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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typedef struct server{

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const char *ip;

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in_port_t port;

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uint16_t port;

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AvahiIfIndex if_index;

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int af;

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struct timespec last_seen;

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/* 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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server *current_server;

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char *interfaces;

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size_t interfaces_size;

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} mandos_context;

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/* global so signal handler can reach it*/

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AvahiSimplePoll *simple_poll;

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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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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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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)))

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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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}

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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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* "buffer_length" is how much is already used.

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*/

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size_t incbuffer(char **buffer, size_t buffer_length,

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size_t buffer_capacity){

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size_t buffer_capacity){

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if(buffer_length + BUFFER_SIZE > buffer_capacity){

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

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if(new_buf == NULL){

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int old_errno = errno;

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free(*buffer);

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errno = old_errno;

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*buffer = NULL;

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

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if(buffer == NULL){

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return 0;

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}

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*buffer = new_buf;

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buffer_capacity += BUFFER_SIZE;

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}

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return buffer_capacity;

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}

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

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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 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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int ret;

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

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if(new_server == NULL){

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perror_plus("malloc");

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return false;

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return -1;

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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){

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perror_plus("strdup");

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return false;

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}

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

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if(ret == -1){

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perror_plus("clock_gettime");

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return false;

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return -1;

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}

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/* Special case of first server */

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if(*current_server == NULL){

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if (mc.current_server == NULL){

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new_server->next = new_server;

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new_server->prev = new_server;

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*current_server = new_server;

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mc.current_server = new_server;

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

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} else {

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new_server->next = *current_server;

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

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new_server->next = mc.current_server;

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

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new_server->prev->next = new_server;

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(*current_server)->prev = new_server;

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}

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return true;

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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){

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perror_plus("clock_gettime");

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return -1;

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}

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return 0;

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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, const char *pubkey,

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const char *tempdir, mandos_context *mc){

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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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gpgme_error_t rc;

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gpgme_engine_info_t engine_info;

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/*

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

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*/

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rc = gpgme_data_new_from_fd(&pgp_data, fd);

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if(rc != GPG_ERR_NO_ERROR){

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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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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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return false;

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}

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rc = gpgme_op_import(mc->ctx, pgp_data);

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rc = gpgme_op_import(mc.ctx, pgp_data);

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if(rc != GPG_ERR_NO_ERROR){

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

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}

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}

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if(debug){

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

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

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}

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/* Init GPGME */

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gpgme_check_version(NULL);

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rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

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if(rc != GPG_ERR_NO_ERROR){

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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fprintf(stderr, "bad gpgme_engine_check_version: %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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/* Set GPGME home directory for the OpenPGP engine only */

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rc = gpgme_get_engine_info(&engine_info);

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if(rc != GPG_ERR_NO_ERROR){

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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fprintf(stderr, "bad gpgme_get_engine_info: %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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while(engine_info != NULL){

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engine_info = engine_info->next;

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}

327

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if(engine_info == NULL){

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

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tempdir);

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

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return false;

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}

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/* Create new GPGME "context" */

334

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

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

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if(rc != GPG_ERR_NO_ERROR){

336

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

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

338

gpgme_strerror(rc));

309

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

310

gpgme_strsource(rc), gpgme_strerror(rc));

339

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return false;

340

312

}

341

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*/

353

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static ssize_t pgp_packet_decrypt(const char *cryptotext,

354

326

size_t crypto_size,

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char **plaintext,

356

mandos_context *mc){

327

char **plaintext){

357

328

gpgme_data_t dh_crypto, dh_plain;

358

329

gpgme_error_t rc;

359

330

ssize_t ret;

361

332

ssize_t plaintext_length = 0;

362

333

363

334

if(debug){

364

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

335

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

365

336

}

366

337

367

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

368

339

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

369

340

0);

370

341

if(rc != GPG_ERR_NO_ERROR){

371

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

372

gpgme_strsource(rc), gpgme_strerror(rc));

342

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

343

gpgme_strsource(rc), gpgme_strerror(rc));

373

344

return -1;

374

345

}

375

346

376

347

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

377

348

rc = gpgme_data_new(&dh_plain);

378

349

if(rc != GPG_ERR_NO_ERROR){

379

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

380

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

381

gpgme_strsource(rc), gpgme_strerror(rc));

350

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

351

gpgme_strsource(rc), gpgme_strerror(rc));

382

352

gpgme_data_release(dh_crypto);

383

353

return -1;

384

354

}

385

355

386

356

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

387

357

data buffer */

388

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

358

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

389

359

if(rc != GPG_ERR_NO_ERROR){

390

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

391

gpgme_strsource(rc), gpgme_strerror(rc));

360

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

361

gpgme_strsource(rc), gpgme_strerror(rc));

392

362

plaintext_length = -1;

393

363

if(debug){

394

364

gpgme_decrypt_result_t result;

395

result = gpgme_op_decrypt_result(mc->ctx);

365

result = gpgme_op_decrypt_result(mc.ctx);

396

366

if(result == NULL){

397

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

367

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

398

368

} else {

399

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

400

result->unsupported_algorithm);

401

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

402

result->wrong_key_usage);

369

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

370

result->unsupported_algorithm);

371

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

372

result->wrong_key_usage);

403

373

if(result->file_name != NULL){

404

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

374

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

405

375

}

406

376

gpgme_recipient_t recipient;

407

377

recipient = result->recipients;

408

378

while(recipient != NULL){

409

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

410

gpgme_pubkey_algo_name

411

(recipient->pubkey_algo));

412

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

413

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

414

recipient->status == GPG_ERR_NO_SECKEY

415

? "No" : "Yes");

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");

416

385

recipient = recipient->next;

417

386

}

418

387

}

421

390

}

422

391

423

392

if(debug){

424

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

393

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

425

394

}

426

395

427

396

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

434

403

*plaintext = NULL;

435

404

while(true){

436

405

plaintext_capacity = incbuffer(plaintext,

437

(size_t)plaintext_length,

438

plaintext_capacity);

406

(size_t)plaintext_length,

407

plaintext_capacity);

439

408

if(plaintext_capacity == 0){

440

perror_plus("incbuffer");

441

plaintext_length = -1;

442

goto decrypt_end;

409

perror_plus("incbuffer");

410

plaintext_length = -1;

411

goto decrypt_end;

443

412

}

444

413

445

414

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

458

427

}

459

428

460

429

if(debug){

461

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

430

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

462

431

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

463

432

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

464

433

}

476

445

}

477

446

478

447

static const char * safer_gnutls_strerror(int value){

479

const char *ret = gnutls_strerror(value);

448

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

449

-Wunreachable-code */

480

450

if(ret == NULL)

481

451

ret = "(unknown)";

482

452

return ret;

485

455

/* GnuTLS log function callback */

486

456

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

487

457

const char* string){

488

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

458

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

489

459

}

490

460

491

461

static int init_gnutls_global(const char *pubkeyfilename,

492

const char *seckeyfilename,

493

mandos_context *mc){

462

const char *seckeyfilename){

494

463

int ret;

495

464

496

465

if(debug){

497

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

466

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

498

467

}

499

468

500

469

ret = gnutls_global_init();

501

470

if(ret != GNUTLS_E_SUCCESS){

502

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

503

safer_gnutls_strerror(ret));

471

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

472

safer_gnutls_strerror(ret));

504

473

return -1;

505

474

}

506

475

513

482

}

514

483

515

484

/* OpenPGP credentials */

516

ret = gnutls_certificate_allocate_credentials(&mc->cred);

485

ret = gnutls_certificate_allocate_credentials(&mc.cred);

517

486

if(ret != GNUTLS_E_SUCCESS){

518

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

519

safer_gnutls_strerror(ret));

487

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

488

safer_gnutls_strerror(ret));

520

489

gnutls_global_deinit();

521

490

return -1;

522

491

}

523

492

524

493

if(debug){

525

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

526

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

527

pubkeyfilename,

528

seckeyfilename);

494

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

495

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

496

seckeyfilename);

529

497

}

530

498

531

499

ret = gnutls_certificate_set_openpgp_key_file

532

(mc->cred, pubkeyfilename, seckeyfilename,

500

(mc.cred, pubkeyfilename, seckeyfilename,

533

501

GNUTLS_OPENPGP_FMT_BASE64);

534

502

if(ret != GNUTLS_E_SUCCESS){

535

fprintf_plus(stderr,

536

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

537

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

538

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

539

safer_gnutls_strerror(ret));

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));

540

508

goto globalfail;

541

509

}

542

510

543

511

/* GnuTLS server initialization */

544

ret = gnutls_dh_params_init(&mc->dh_params);

512

ret = gnutls_dh_params_init(&mc.dh_params);

545

513

if(ret != GNUTLS_E_SUCCESS){

546

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

547

" initialization: %s\n",

548

safer_gnutls_strerror(ret));

514

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

515

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

549

516

goto globalfail;

550

517

}

551

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

518

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

552

519

if(ret != GNUTLS_E_SUCCESS){

553

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

554

safer_gnutls_strerror(ret));

520

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

521

safer_gnutls_strerror(ret));

555

522

goto globalfail;

556

523

}

557

524

558

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

525

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

559

526

560

527

return 0;

561

528

562

529

globalfail:

563

530

564

gnutls_certificate_free_credentials(mc->cred);

531

gnutls_certificate_free_credentials(mc.cred);

565

532

gnutls_global_deinit();

566

gnutls_dh_params_deinit(mc->dh_params);

533

gnutls_dh_params_deinit(mc.dh_params);

567

534

return -1;

568

535

}

569

536

570

static int init_gnutls_session(gnutls_session_t *session,

571

mandos_context *mc){

537

static int init_gnutls_session(gnutls_session_t *session){

572

538

int ret;

573

539

/* GnuTLS session creation */

574

540

do {

578

544

}

579

545

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

580

546

if(ret != GNUTLS_E_SUCCESS){

581

fprintf_plus(stderr,

582

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

583

safer_gnutls_strerror(ret));

547

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

548

safer_gnutls_strerror(ret));

584

549

}

585

550

586

551

{

587

552

const char *err;

588

553

do {

589

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

554

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

590

555

if(quit_now){

591

556

gnutls_deinit(*session);

592

557

return -1;

593

558

}

594

559

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

595

560

if(ret != GNUTLS_E_SUCCESS){

596

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

597

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

598

safer_gnutls_strerror(ret));

561

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

562

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

563

safer_gnutls_strerror(ret));

599

564

gnutls_deinit(*session);

600

565

return -1;

601

566

}

603

568

604

569

do {

605

570

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

606

mc->cred);

571

mc.cred);

607

572

if(quit_now){

608

573

gnutls_deinit(*session);

609

574

return -1;

610

575

}

611

576

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

612

577

if(ret != GNUTLS_E_SUCCESS){

613

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

614

safer_gnutls_strerror(ret));

578

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

579

safer_gnutls_strerror(ret));

615

580

gnutls_deinit(*session);

616

581

return -1;

617

582

}

619

584

/* ignore client certificate if any. */

620

585

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

621

586

622

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

587

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

623

588

624

589

return 0;

625

590

}

629

594

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

630

595

631

596

/* Called when a Mandos server is found */

632

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

597

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

633

598

AvahiIfIndex if_index,

634

int af, mandos_context *mc){

599

int af){

635

600

int ret, tcp_sd = -1;

636

601

ssize_t sret;

637

struct sockaddr_storage to;

602

union {

603

struct sockaddr_in in;

604

struct sockaddr_in6 in6;

605

} to;

638

606

char *buffer = NULL;

639

607

char *decrypted_buffer = NULL;

640

608

size_t buffer_length = 0;

659

627

pf = PF_INET;

660

628

break;

661

629

default:

662

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

630

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

663

631

errno = EINVAL;

664

632

return -1;

665

633

}

666

634

667

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

668

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

669

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

670

bool match = false;

671

{

672

char *interface = NULL;

673

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

674

interface))){

675

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

676

match = true;

677

break;

678

}

679

}

680

}

681

if(not match){

682

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

683

connect to the server */

684

if(debug){

685

char interface[IF_NAMESIZE];

686

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

687

perror_plus("if_indextoname");

688

} else {

689

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

690

" \"%s\"\n",

691

if_indextoname((unsigned int)if_index,

692

interface));

693

}

694

}

695

return -1;

696

}

697

}

698

699

ret = init_gnutls_session(&session, mc);

635

ret = init_gnutls_session(&session);

700

636

if(ret != 0){

701

637

return -1;

702

638

}

703

639

704

640

if(debug){

705

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

706

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

641

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

642

"\n", ip, port);

707

643

}

708

644

709

645

tcp_sd = socket(pf, SOCK_STREAM, 0);

721

657

722

658

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

723

659

if(af == AF_INET6){

724

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

725

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

660

to.in6.sin6_family = (sa_family_t)af;

661

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

726

662

} else { /* IPv4 */

727

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

728

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

663

to.in.sin_family = (sa_family_t)af;

664

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

729

665

}

730

666

if(ret < 0 ){

731

667

int e = errno;

735

671

}

736

672

if(ret == 0){

737

673

int e = errno;

738

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

674

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

739

675

errno = e;

740

676

goto mandos_end;

741

677

}

742

678

if(af == AF_INET6){

743

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

744

if(IN6_IS_ADDR_LINKLOCAL

745

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

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*/

746

686

if(if_index == AVAHI_IF_UNSPEC){

747

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

748

" incomplete without a network interface\n");

687

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

688

" without a network interface\n");

749

689

errno = EINVAL;

750

690

goto mandos_end;

751

691

}

752

692

/* Set the network interface number as scope */

753

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

693

to.in6.sin6_scope_id = (uint32_t)if_index;

754

694

}

755

695

} else {

756

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

696

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

697

-Wconversion and

698

-Wunreachable-code */

757

699

}

758

700

759

701

if(quit_now){

767

709

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

768

710

perror_plus("if_indextoname");

769

711

} else {

770

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

771

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

712

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

713

ip, interface, port);

772

714

}

773

715

} else {

774

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

775

ip, (uintmax_t)port);

716

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

717

port);

776

718

}

777

719

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

778

720

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

721

const char *pcret;

779

722

if(af == AF_INET6){

780

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

781

sizeof(struct sockaddr_in6),

782

addrstr, sizeof(addrstr), NULL, 0,

783

NI_NUMERICHOST);

723

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

724

sizeof(addrstr));

784

725

} else {

785

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

786

sizeof(struct sockaddr_in),

787

addrstr, sizeof(addrstr), NULL, 0,

788

NI_NUMERICHOST);

726

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

727

sizeof(addrstr));

789

728

}

790

if(ret == EAI_SYSTEM){

791

perror_plus("getnameinfo");

792

} else if(ret != 0) {

793

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

794

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

795

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

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

}

796

735

}

797

736

}

798

737

802

741

}

803

742

804

743

if(af == AF_INET6){

805

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

806

sizeof(struct sockaddr_in6));

744

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

807

745

} else {

808

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

809

sizeof(struct sockaddr_in));

746

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

810

747

}

811

748

if(ret < 0){

812

749

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

827

764

while(true){

828

765

size_t out_size = strlen(out);

829

766

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

830

out_size - written));

767

out_size - written));

831

768

if(ret == -1){

832

769

int e = errno;

833

770

perror_plus("write");

853

790

}

854

791

855

792

if(debug){

856

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

793

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

857

794

}

858

795

859

796

if(quit_now){

861

798

goto mandos_end;

862

799

}

863

800

864

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

865

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

866

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

867

gnutls_transport_set_ptr(session,

868

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

801

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

802

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

869

803

870

804

if(quit_now){

871

805

errno = EINTR;

882

816

883

817

if(ret != GNUTLS_E_SUCCESS){

884

818

if(debug){

885

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

819

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

886

820

gnutls_perror(ret);

887

821

}

888

822

errno = EPROTO;

892

826

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

893

827

894

828

if(debug){

895

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

896

" %s\n", ip);

829

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

830

ip);

897

831

}

898

832

899

833

while(true){

904

838

}

905

839

906

840

buffer_capacity = incbuffer(&buffer, buffer_length,

907

buffer_capacity);

841

buffer_capacity);

908

842

if(buffer_capacity == 0){

909

843

int e = errno;

910

844

perror_plus("incbuffer");

937

871

}

938

872

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

939

873

if(ret < 0){

940

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

941

"***\n");

874

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

942

875

gnutls_perror(ret);

943

876

errno = EPROTO;

944

877

goto mandos_end;

945

878

}

946

879

break;

947

880

default:

948

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

949

" encrypted session with Mandos server\n");

881

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

882

" encrypted session with Mandos server\n");

950

883

gnutls_bye(session, GNUTLS_SHUT_RDWR);

951

884

errno = EIO;

952

885

goto mandos_end;

957

890

}

958

891

959

892

if(debug){

960

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

893

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

961

894

}

962

895

963

896

if(quit_now){

975

908

976

909

if(buffer_length > 0){

977

910

ssize_t decrypted_buffer_size;

978

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

979

&decrypted_buffer, mc);

911

decrypted_buffer_size = pgp_packet_decrypt(buffer,

912

buffer_length,

913

&decrypted_buffer);

980

914

if(decrypted_buffer_size >= 0){

981

915

982

916

written = 0;

992

926

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

993

927

int e = errno;

994

928

if(debug){

995

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

996

strerror(errno));

929

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

930

strerror(errno));

997

931

}

998

932

errno = e;

999

933

goto mandos_end;

1043

977

AVAHI_GCC_UNUSED AvahiStringList *txt,

1044

978

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1045

979

flags,

1046

void* mc){

1047

if(r == NULL){

1048

return;

1049

}

980

AVAHI_GCC_UNUSED void* userdata){

981

assert(r);

1050

982

1051

983

/* Called whenever a service has been resolved successfully or

1052

984

timed out */

1058

990

switch(event){

1059

991

default:

1060

992

case AVAHI_RESOLVER_FAILURE:

1061

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

1062

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

1063

domain,

1064

avahi_strerror(avahi_server_errno

1065

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

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)));

1066

996

break;

1067

997

1068

998

case AVAHI_RESOLVER_FOUND:

1070

1000

char ip[AVAHI_ADDRESS_STR_MAX];

1071

1001

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

1072

1002

if(debug){

1073

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

1074

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

1075

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

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);

1076

1006

}

1077

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

1078

interface,

1079

avahi_proto_to_af(proto),

1080

mc);

1007

int ret = start_mandos_communication(ip, port, interface,

1008

avahi_proto_to_af(proto));

1081

1009

if(ret == 0){

1082

avahi_simple_poll_quit(simple_poll);

1010

avahi_simple_poll_quit(mc.simple_poll);

1083

1011

} else {

1084

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

1085

avahi_proto_to_af(proto),

1086

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

1087

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

1088

" list\n", name);

1089

}

1012

ret = add_server(ip, port, interface,

1013

avahi_proto_to_af(proto));

1090

1014

}

1091

1015

}

1092

1016

}

1102

1026

const char *domain,

1103

1027

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1104

1028

flags,

1105

void* mc){

1106

if(b == NULL){

1107

return;

1108

}

1029

AVAHI_GCC_UNUSED void* userdata){

1030

assert(b);

1109

1031

1110

1032

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

1111

1033

is removed from the LAN */

1118

1040

default:

1119

1041

case AVAHI_BROWSER_FAILURE:

1120

1042

1121

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

1122

avahi_strerror(avahi_server_errno

1123

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

1124

avahi_simple_poll_quit(simple_poll);

1043

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

1044

avahi_strerror(avahi_server_errno(mc.server)));

1045

avahi_simple_poll_quit(mc.simple_poll);

1125

1046

return;

1126

1047

1127

1048

case AVAHI_BROWSER_NEW:

1130

1051

the callback function is called the Avahi server will free the

1131

1052

resolver for us. */

1132

1053

1133

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

1134

interface, protocol, name, type,

1135

domain, protocol, 0,

1136

resolve_callback, mc) == NULL)

1137

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

1138

" %s\n", name,

1139

avahi_strerror(avahi_server_errno

1140

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

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)));

1141

1059

break;

1142

1060

1143

1061

case AVAHI_BROWSER_REMOVE:

1146

1064

case AVAHI_BROWSER_ALL_FOR_NOW:

1147

1065

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1148

1066

if(debug){

1149

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

1150

" searching...\n");

1067

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

1151

1068

}

1152

1069

break;

1153

1070

}

1162

1079

signal_received = sig;

1163

1080

int old_errno = errno;

1164

1081

/* set main loop to exit */

1165

if(simple_poll != NULL){

1166

avahi_simple_poll_quit(simple_poll);

1082

if(mc.simple_poll != NULL){

1083

avahi_simple_poll_quit(mc.simple_poll);

1167

1084

}

1168

1085

errno = old_errno;

1169

1086

}

1170

1087

1171

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

1172

int ret;

1173

error_t ret_errno;

1174

1175

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

1176

if(s < 0){

1177

ret_errno = errno;

1178

perror_plus("socket");

1179

errno = ret_errno;

1180

return false;

1181

}

1182

strcpy(ifr->ifr_name, ifname);

1183

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1184

if(ret == -1){

1088

/*

1089

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

1090

* corresponds to an acceptable network device.

1091

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

1092

*/

1093

int good_interface(const struct dirent *if_entry){

1094

ssize_t ssret;

1095

char *flagname = NULL;

1096

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

1097

return 0;

1098

}

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){

1185

1144

if(debug){

1186

ret_errno = errno;

1187

perror_plus("ioctl SIOCGIFFLAGS");

1188

errno = ret_errno;

1145

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

1146

flagstring, if_entry->d_name);

1189

1147

}

1190

return false;

1148

free(flagstring);

1149

return 0;

1191

1150

}

1192

return true;

1193

}

1194

1195

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

1196

1151

free(flagstring);

1152

ifreq_flags flags = (ifreq_flags)tmpmax;

1197

1153

/* Reject the loopback device */

1198

if(ifr->ifr_flags & IFF_LOOPBACK){

1154

if(flags & IFF_LOOPBACK){

1199

1155

if(debug){

1200

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

1201

ifname);

1156

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

1157

if_entry->d_name);

1202

1158

}

1203

return false;

1159

return 0;

1204

1160

}

1205

1161

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

1206

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

1162

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

1207

1163

if(debug){

1208

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

1209

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

1164

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

1165

if_entry->d_name);

1210

1166

}

1211

return true;

1167

return 1;

1212

1168

}

1213

1169

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

1214

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

1170

if(not (flags & IFF_BROADCAST)){

1215

1171

if(debug){

1216

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1217

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

1172

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

1173

if_entry->d_name);

1218

1174

}

1219

return false;

1175

return 0;

1220

1176

}

1221

1177

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

1222

if(ifr->ifr_flags & IFF_NOARP){

1178

if(flags & IFF_NOARP){

1223

1179

if(debug){

1224

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

1225

ifname);

1180

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

1181

if_entry->d_name);

1226

1182

}

1227

return false;

1183

return 0;

1228

1184

}

1229

1230

1185

/* Accept this device */

1231

1186

if(debug){

1232

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

1233

}

1234

return true;

1235

}

1236

1237

/*

1238

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

1239

* corresponds to an acceptable network device.

1240

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

1241

*/

1242

int good_interface(const struct dirent *if_entry){

1243

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

1244

return 0;

1245

}

1246

1247

struct ifreq ifr;

1248

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

1249

if(debug){

1250

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

1251

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

1252

}

1253

return 0;

1254

}

1255

1256

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

1257

return 0;

1187

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

1188

if_entry->d_name);

1258

1189

}

1259

1190

return 1;

1260

1191

}

1261

1192

1262

/*

1263

* This function determines if a network interface is up.

1264

*/

1265

bool interface_is_up(const char *interface){

1266

struct ifreq ifr;

1267

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

1268

if(debug){

1269

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

1270

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

1271

}

1272

return false;

1273

}

1274

1275

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

1276

}

1277

1278

/*

1279

* This function determines if a network interface is running

1280

*/

1281

bool interface_is_running(const char *interface){

1282

struct ifreq ifr;

1283

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

1284

if(debug){

1285

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

1286

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

1287

}

1288

return false;

1289

}

1290

1291

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

1292

}

1293

1294

1193

int notdotentries(const struct dirent *direntry){

1295

1194

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

1296

1195

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

1302

1201

return 1;

1303

1202

}

1304

1203

1305

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

1306

int runnable_hook(const struct dirent *direntry){

1307

int ret;

1308

size_t sret;

1309

struct stat st;

1310

1311

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

1312

/* Empty name? */

1313

return 0;

1314

}

1315

1316

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

1317

"abcdefghijklmnopqrstuvwxyz"

1318

"0123456789"

1319

"_-");

1320

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

1321

/* Contains non-allowed characters */

1322

if(debug){

1323

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

1324

direntry->d_name);

1325

}

1326

return 0;

1327

}

1328

1329

char *fullname = NULL;

1330

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

1331

if(ret < 0){

1332

perror_plus("asprintf");

1333

return 0;

1334

}

1335

1336

ret = stat(fullname, &st);

1337

if(ret == -1){

1338

if(debug){

1339

perror_plus("Could not stat hook");

1340

}

1341

return 0;

1342

}

1343

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

1344

/* Not a regular file */

1345

if(debug){

1346

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

1347

direntry->d_name);

1348

}

1349

return 0;

1350

}

1351

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

1352

/* Not executable */

1353

if(debug){

1354

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

1355

direntry->d_name);

1356

}

1357

return 0;

1358

}

1359

if(debug){

1360

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

1361

direntry->d_name);

1362

}

1363

return 1;

1364

}

1365

1366

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1367

mandos_context *mc){

1204

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1368

1205

int ret;

1369

1206

struct timespec now;

1370

1207

struct timespec waited_time;

1371

1208

intmax_t block_time;

1372

1209

1373

1210

while(true){

1374

if(mc->current_server == NULL){

1211

if(mc.current_server == NULL){

1375

1212

if (debug){

1376

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

1377

" No timeout!\n");

1213

fprintf(stderr,

1214

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

1378

1215

}

1379

1216

ret = avahi_simple_poll_iterate(s, -1);

1380

1217

} else {

1381

1218

if (debug){

1382

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

1383

" it, or wait\n");

1219

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

1220

" or wait\n");

1384

1221

}

1385

1222

/* the current time */

1386

1223

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1391

1228

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

1392

1229

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

1393

1230

waited_time.tv_sec = (now.tv_sec

1394

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

1231

- mc.current_server->last_seen.tv_sec);

1395

1232

waited_time.tv_nsec = (now.tv_nsec

1396

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

1233

- mc.current_server->last_seen.tv_nsec);

1397

1234

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

1398

1235

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

1399

1236

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

1402

1239

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

1403

1240

1404

1241

if (debug){

1405

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

1406

block_time);

1242

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

1407

1243

}

1408

1244

1409

1245

if(block_time <= 0){

1410

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

1411

mc->current_server->port,

1412

mc->current_server->if_index,

1413

mc->current_server->af, mc);

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);

1414

1250

if(ret == 0){

1415

avahi_simple_poll_quit(s);

1251

avahi_simple_poll_quit(mc.simple_poll);

1416

1252

return 0;

1417

1253

}

1418

1254

ret = clock_gettime(CLOCK_MONOTONIC,

1419

&mc->current_server->last_seen);

1255

&mc.current_server->last_seen);

1420

1256

if(ret == -1){

1421

1257

perror_plus("clock_gettime");

1422

1258

return -1;

1423

1259

}

1424

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

1260

mc.current_server = mc.current_server->next;

1425

1261

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

1426

1262

servers, but don't block */

1427

1263

}

1429

1265

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

1430

1266

}

1431

1267

if(ret != 0){

1432

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

1268

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

1433

1269

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

1434

1270

}

1435

1271

}

1436

1272

}

1437

1273

}

1438

1274

1439

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

1440

error_t raise_privileges(void){

1441

error_t old_errno = errno;

1442

error_t ret_errno = 0;

1443

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

1444

ret_errno = errno;

1445

perror_plus("seteuid");

1446

}

1447

errno = old_errno;

1448

return ret_errno;

1449

}

1450

1451

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

1452

error_t raise_privileges_permanently(void){

1453

error_t old_errno = errno;

1454

error_t ret_errno = raise_privileges();

1455

if(ret_errno != 0){

1456

errno = old_errno;

1457

return ret_errno;

1458

}

1459

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

1460

ret_errno = errno;

1461

perror_plus("seteuid");

1462

}

1463

errno = old_errno;

1464

return ret_errno;

1465

}

1466

1467

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

1468

error_t lower_privileges(void){

1469

error_t old_errno = errno;

1470

error_t ret_errno = 0;

1471

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

1472

ret_errno = errno;

1473

perror_plus("seteuid");

1474

}

1475

errno = old_errno;

1476

return ret_errno;

1477

}

1478

1479

/* Lower privileges permanently */

1480

error_t lower_privileges_permanently(void){

1481

error_t old_errno = errno;

1482

error_t ret_errno = 0;

1483

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

1484

ret_errno = errno;

1485

perror_plus("setuid");

1486

}

1487

errno = old_errno;

1488

return ret_errno;

1489

}

1490

1491

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

1492

const float delay){

1493

struct dirent **direntries;

1494

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

1495

alphasort);

1496

if(numhooks == -1){

1497

if(errno == ENOENT){

1498

if(debug){

1499

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

1500

" found\n", hookdir);

1501

}

1502

} else {

1503

perror_plus("scandir");

1504

}

1505

} else {

1506

struct dirent *direntry;

1507

int ret;

1508

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

1509

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

1510

direntry = direntries[i];

1511

char *fullname = NULL;

1512

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

1513

if(ret < 0){

1514

perror_plus("asprintf");

1515

continue;

1516

}

1517

if(debug){

1518

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

1519

direntry->d_name);

1520

}

1521

pid_t hook_pid = fork();

1522

if(hook_pid == 0){

1523

/* Child */

1524

/* Raise privileges */

1525

raise_privileges_permanently();

1526

/* Set group */

1527

errno = 0;

1528

ret = setgid(0);

1529

if(ret == -1){

1530

perror_plus("setgid");

1531

}

1532

/* Reset supplementary groups */

1533

errno = 0;

1534

ret = setgroups(0, NULL);

1535

if(ret == -1){

1536

perror_plus("setgroups");

1537

}

1538

dup2(devnull, STDIN_FILENO);

1539

close(devnull);

1540

dup2(STDERR_FILENO, STDOUT_FILENO);

1541

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

1542

if(ret == -1){

1543

perror_plus("setenv");

1544

_exit(EX_OSERR);

1545

}

1546

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

1547

if(ret == -1){

1548

perror_plus("setenv");

1549

_exit(EX_OSERR);

1550

}

1551

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

1552

if(ret == -1){

1553

perror_plus("setenv");

1554

_exit(EX_OSERR);

1555

}

1556

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

1557

if(ret == -1){

1558

perror_plus("setenv");

1559

_exit(EX_OSERR);

1560

}

1561

char *delaystring;

1562

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

1563

if(ret == -1){

1564

perror_plus("asprintf");

1565

_exit(EX_OSERR);

1566

}

1567

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

1568

if(ret == -1){

1569

free(delaystring);

1570

perror_plus("setenv");

1571

_exit(EX_OSERR);

1572

}

1573

free(delaystring);

1574

if(connect_to != NULL){

1575

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

1576

if(ret == -1){

1577

perror_plus("setenv");

1578

_exit(EX_OSERR);

1579

}

1580

}

1581

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

1582

perror_plus("execl");

1583

_exit(EXIT_FAILURE);

1584

}

1585

} else {

1586

int status;

1587

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

1588

perror_plus("waitpid");

1589

free(fullname);

1590

continue;

1591

}

1592

if(WIFEXITED(status)){

1593

if(WEXITSTATUS(status) != 0){

1594

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

1595

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

1596

WEXITSTATUS(status));

1597

free(fullname);

1598

continue;

1599

}

1600

} else if(WIFSIGNALED(status)){

1601

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

1602

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

1603

WTERMSIG(status));

1604

free(fullname);

1605

continue;

1606

} else {

1607

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

1608

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

1609

free(fullname);

1610

continue;

1611

}

1612

}

1613

free(fullname);

1614

if(debug){

1615

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

1616

direntry->d_name);

1617

}

1618

}

1619

close(devnull);

1620

}

1621

return true;

1622

}

1623

1624

error_t bring_up_interface(const char *const interface,

1625

const float delay){

1626

int sd = -1;

1627

error_t old_errno = errno;

1628

error_t ret_errno = 0;

1629

int ret, ret_setflags;

1630

struct ifreq network;

1631

unsigned int if_index = if_nametoindex(interface);

1632

if(if_index == 0){

1633

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

1634

errno = old_errno;

1635

return ENXIO;

1636

}

1637

1638

if(quit_now){

1639

errno = old_errno;

1640

return EINTR;

1641

}

1642

1643

if(not interface_is_up(interface)){

1644

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

1645

ret_errno = errno;

1646

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

1647

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

1648

return ret_errno;

1649

}

1650

network.ifr_flags |= IFF_UP;

1651

1652

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1653

if(sd < 0){

1654

ret_errno = errno;

1655

perror_plus("socket");

1656

errno = old_errno;

1657

return ret_errno;

1658

}

1659

1660

if(quit_now){

1661

close(sd);

1662

errno = old_errno;

1663

return EINTR;

1664

}

1665

1666

if(debug){

1667

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

1668

interface);

1669

}

1670

1671

/* Raise priviliges */

1672

raise_privileges();

1673

1674

#ifdef __linux__

1675

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1676

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

1677

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

1678

bool restore_loglevel = true;

1679

if(ret_linux == -1){

1680

restore_loglevel = false;

1681

perror_plus("klogctl");

1682

}

1683

#endif /* __linux__ */

1684

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

1685

ret_errno = errno;

1686

#ifdef __linux__

1687

if(restore_loglevel){

1688

ret_linux = klogctl(7, NULL, 0);

1689

if(ret_linux == -1){

1690

perror_plus("klogctl");

1691

}

1692

}

1693

#endif /* __linux__ */

1694

1695

/* Lower privileges */

1696

lower_privileges();

1697

1698

/* Close the socket */

1699

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

1700

if(ret == -1){

1701

perror_plus("close");

1702

}

1703

1704

if(ret_setflags == -1){

1705

errno = ret_errno;

1706

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1707

errno = old_errno;

1708

return ret_errno;

1709

}

1710

} else if(debug){

1711

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

1712

interface);

1713

}

1714

1715

/* Sleep checking until interface is running.

1716

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

1717

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

1718

if(interface_is_running(interface)){

1719

break;

1720

}

1721

struct timespec sleeptime = { .tv_nsec = 250000000 };

1722

ret = nanosleep(&sleeptime, NULL);

1723

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

1724

perror_plus("nanosleep");

1725

}

1726

}

1727

1728

errno = old_errno;

1729

return 0;

1730

}

1731

1732

error_t take_down_interface(const char *const interface){

1733

error_t old_errno = errno;

1734

struct ifreq network;

1735

unsigned int if_index = if_nametoindex(interface);

1736

if(if_index == 0){

1737

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

1738

errno = old_errno;

1739

return ENXIO;

1740

}

1741

if(interface_is_up(interface)){

1742

error_t ret_errno = 0;

1743

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

1744

ret_errno = errno;

1745

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

1746

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

1747

return ret_errno;

1748

}

1749

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

1750

1751

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

1752

if(sd < 0){

1753

ret_errno = errno;

1754

perror_plus("socket");

1755

errno = old_errno;

1756

return ret_errno;

1757

}

1758

1759

if(debug){

1760

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

1761

interface);

1762

}

1763

1764

/* Raise priviliges */

1765

raise_privileges();

1766

1767

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

1768

ret_errno = errno;

1769

1770

/* Lower privileges */

1771

lower_privileges();

1772

1773

/* Close the socket */

1774

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

1775

if(ret == -1){

1776

perror_plus("close");

1777

}

1778

1779

if(ret_setflags == -1){

1780

errno = ret_errno;

1781

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1782

errno = old_errno;

1783

return ret_errno;

1784

}

1785

} else if(debug){

1786

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

1787

interface);

1788

}

1789

1790

errno = old_errno;

1791

return 0;

1792

}

1793

1794

1275

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

1795

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

1796

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

1797

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

1798

.interfaces = NULL, .interfaces_size = 0 };

1799

1276

AvahiSServiceBrowser *sb = NULL;

1800

error_t ret_errno;

1277

int error;

1801

1278

int ret;

1802

1279

intmax_t tmpmax;

1803

1280

char *tmp;

1804

1281

int exitcode = EXIT_SUCCESS;

1805

char *interfaces_to_take_down = NULL;

1806

size_t interfaces_to_take_down_size = 0;

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;

1807

1288

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

1808

1289

bool tempdir_created = false;

1809

1290

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1810

1291

const char *seckey = PATHDIR "/" SECKEY;

1811

1292

const char *pubkey = PATHDIR "/" PUBKEY;

1812

char *interfaces_hooks = NULL;

1813

1293

1814

1294

bool gnutls_initialized = false;

1815

1295

bool gpgme_initialized = false;

1877

1357

.group = 2 },

1878

1358

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

1879

1359

.arg = "SECONDS",

1880

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

1881

.group = 2 },

1882

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

1883

.arg = "DIR",

1884

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

1360

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

1885

1361

.group = 2 },

1886

1362

/*

1887

1363

* These reproduce what we would get without ARGP_NO_HELP

1906

1382

connect_to = arg;

1907

1383

break;

1908

1384

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

1909

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

1910

arg, (int)',');

1911

if(ret_errno != 0){

1912

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

1913

}

1385

interface = arg;

1914

1386

break;

1915

1387

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

1916

1388

seckey = arg;

1945

1417

argp_error(state, "Bad retry interval");

1946

1418

}

1947

1419

break;

1948

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

1949

hookdir = arg;

1950

break;

1951

1420

/*

1952

1421

* These reproduce what we would get without ARGP_NO_HELP

1953

1422

*/

1959

1428

argp_state_help(state, state->out_stream,

1960

1429

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1961

1430

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

1962

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

1431

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

1963

1432

exit(argp_err_exit_status);

1964

1433

break;

1965

1434

default:

1992

1461

{

1993

1462

/* Work around Debian bug #633582:

1994

1463

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

1464

struct stat st;

1995

1465

1996

1466

/* Re-raise priviliges */

1997

if(raise_privileges() == 0){

1998

struct stat st;

1999

2000

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

2001

int seckey_fd = open(seckey, O_RDONLY);

2002

if(seckey_fd == -1){

2003

perror_plus("open");

2004

} else {

2005

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

2006

if(ret == -1){

2007

perror_plus("fstat");

2008

} else {

2009

if(S_ISREG(st.st_mode)

2010

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

2011

ret = fchown(seckey_fd, uid, gid);

2012

if(ret == -1){

2013

perror_plus("fchown");

2014

}

2015

}

2016

}

2017

TEMP_FAILURE_RETRY(close(seckey_fd));

2018

}

2019

}

2020

2021

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

2022

int pubkey_fd = open(pubkey, O_RDONLY);

2023

if(pubkey_fd == -1){

2024

perror_plus("open");

2025

} else {

2026

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

2027

if(ret == -1){

2028

perror_plus("fstat");

2029

} else {

2030

if(S_ISREG(st.st_mode)

2031

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

2032

ret = fchown(pubkey_fd, uid, gid);

2033

if(ret == -1){

2034

perror_plus("fchown");

2035

}

2036

}

2037

}

2038

TEMP_FAILURE_RETRY(close(pubkey_fd));

2039

}

2040

}

2041

2042

/* Lower privileges */

2043

lower_privileges();

2044

}

2045

}

2046

2047

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

2048

{

2049

char *interface = NULL;

2050

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

2051

interface))){

2052

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

2053

and if_nametoindex(interface) == 0){

2054

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

2055

fprintf_plus(stderr, "Not using nonexisting interface"

2056

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

2057

}

2058

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

2059

interface = NULL;

2060

}

2061

}

2062

}

2063

2064

/* Run network hooks */

2065

{

2066

if(mc.interfaces != NULL){

2067

interfaces_hooks = malloc(mc.interfaces_size);

2068

if(interfaces_hooks == NULL){

2069

perror_plus("malloc");

2070

goto end;

2071

}

2072

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

2073

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

2074

}

2075

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

2076

interfaces_hooks : "", delay)){

2077

goto end;

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");

2078

1518

}

2079

1519

}

2080

1520

2081

1521

if(not debug){

2082

1522

avahi_set_log_function(empty_log);

2083

1523

}

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

}

2084

1549

2085

1550

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

2086

1551

from the signal handler */

2087

1552

/* Initialize the pseudo-RNG for Avahi */

2088

1553

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

2089

simple_poll = avahi_simple_poll_new();

2090

if(simple_poll == NULL){

2091

fprintf_plus(stderr,

2092

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

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");

2093

1557

exitcode = EX_UNAVAILABLE;

2094

1558

goto end;

2095

1559

}

2157

1621

}

2158

1622

}

2159

1623

2160

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

2161

if(mc.interfaces == NULL){

2162

struct dirent **direntries;

2163

/* Look for any good interfaces */

2164

ret = scandir(sys_class_net, &direntries, good_interface,

2165

alphasort);

2166

if(ret >= 1){

2167

/* Add all found interfaces to interfaces list */

2168

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

2169

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

2170

direntries[i]->d_name);

2171

if(ret_errno != 0){

2172

errno = ret_errno;

2173

perror_plus("argz_add");

2174

continue;

2175

}

2176

if(debug){

2177

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

2178

direntries[i]->d_name);

2179

}

2180

}

2181

free(direntries);

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");

1709

}

1710

}

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

break;

1729

}

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

}

2182

1760

} else {

2183

free(direntries);

2184

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

2185

exitcode = EXIT_FAILURE;

2186

goto end;

2187

}

2188

}

2189

2190

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

2191

{

2192

char *interface = NULL;

2193

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

2194

interface))){

2195

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

2196

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

2197

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

2198

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

2199

interface);

2200

interface = NULL;

2201

while((interface = argz_next(mc.interfaces,

2202

mc.interfaces_size, interface))){

2203

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

2204

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

2205

interface);

2206

interface = NULL;

2207

}

2208

}

2209

break;

2210

}

2211

bool interface_was_up = interface_is_up(interface);

2212

ret = bring_up_interface(interface, delay);

2213

if(not interface_was_up){

2214

if(ret != 0){

2215

errno = ret;

2216

perror_plus("Failed to bring up interface");

2217

} else {

2218

ret_errno = argz_add(&interfaces_to_take_down,

2219

&interfaces_to_take_down_size,

2220

interface);

2221

if(ret_errno != 0){

2222

errno = ret_errno;

2223

perror_plus("argz_add");

2224

}

2225

}

2226

}

2227

}

2228

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

2229

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

2230

}

2231

}

2232

2233

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

2234

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

2235

if(debug){

2236

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

2237

mc.interfaces);

2238

}

2239

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

1761

/* Lower privileges permanently */

1762

ret = setuid(uid);

1763

if(ret == -1){

1764

perror_plus("setuid");

1765

}

1766

}

2240

1767

}

2241

1768

2242

1769

if(quit_now){

2243

1770

goto end;

2244

1771

}

2245

1772

2246

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

1773

ret = init_gnutls_global(pubkey, seckey);

2247

1774

if(ret == -1){

2248

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

1775

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

2249

1776

exitcode = EX_UNAVAILABLE;

2250

1777

goto end;

2251

1778

} else {

2266

1793

goto end;

2267

1794

}

2268

1795

2269

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

2270

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

1796

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

1797

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

2271

1798

exitcode = EX_UNAVAILABLE;

2272

1799

goto end;

2273

1800

} else {

2282

1809

/* Connect directly, do not use Zeroconf */

2283

1810

/* (Mainly meant for debugging) */

2284

1811

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

2285

2286

1812

if(address == NULL){

2287

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

1813

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

2288

1814

exitcode = EX_USAGE;

2289

1815

goto end;

2290

1816

}

2293

1819

goto end;

2294

1820

}

2295

1821

2296

in_port_t port;

1822

uint16_t port;

2297

1823

errno = 0;

2298

1824

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

2299

1825

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

2300

or tmpmax != (in_port_t)tmpmax){

2301

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

1826

or tmpmax != (uint16_t)tmpmax){

1827

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

2302

1828

exitcode = EX_USAGE;

2303

1829

goto end;

2304

1830

}

2305

1831

2306

1832

if(quit_now){

2307

1833

goto end;

2308

1834

}

2309

1835

2310

port = (in_port_t)tmpmax;

1836

port = (uint16_t)tmpmax;

2311

1837

*address = '\0';

2312

1838

/* Colon in address indicates IPv6 */

2313

1839

int af;

2329

1855

}

2330

1856

2331

1857

while(not quit_now){

2332

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

2333

&mc);

1858

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

2334

1859

if(quit_now or ret == 0){

2335

1860

break;

2336

1861

}

2337

1862

if(debug){

2338

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

2339

(int)retry_interval);

1863

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

1864

(int)retry_interval);

2340

1865

}

2341

sleep((unsigned int)retry_interval);

1866

sleep((int)retry_interval);

2342

1867

}

2343

1868

2344

1869

if (not quit_now){

2345

1870

exitcode = EXIT_SUCCESS;

2346

1871

}

2347

1872

2348

1873

goto end;

2349

1874

}

2350

1875

2362

1887

config.publish_domain = 0;

2363

1888

2364

1889

/* Allocate a new server */

2365

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2366

&config, NULL, NULL, &ret_errno);

1890

mc.server = avahi_server_new(avahi_simple_poll_get

1891

(mc.simple_poll), &config, NULL,

1892

NULL, &error);

2367

1893

2368

1894

/* Free the Avahi configuration data */

2369

1895

avahi_server_config_free(&config);

2371

1897

2372

1898

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

2373

1899

if(mc.server == NULL){

2374

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

2375

avahi_strerror(ret_errno));

1900

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

1901

avahi_strerror(error));

2376

1902

exitcode = EX_UNAVAILABLE;

2377

1903

goto end;

2378

1904

}

2384

1910

/* Create the Avahi service browser */

2385

1911

sb = avahi_s_service_browser_new(mc.server, if_index,

2386

1912

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2387

NULL, 0, browse_callback,

2388

(void *)&mc);

1913

NULL, 0, browse_callback, NULL);

2389

1914

if(sb == NULL){

2390

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

2391

avahi_strerror(avahi_server_errno(mc.server)));

1915

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

1916

avahi_strerror(avahi_server_errno(mc.server)));

2392

1917

exitcode = EX_UNAVAILABLE;

2393

1918

goto end;

2394

1919

}

2400

1925

/* Run the main loop */

2401

1926

2402

1927

if(debug){

2403

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

1928

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

2404

1929

}

2405

1930

2406

ret = avahi_loop_with_timeout(simple_poll,

2407

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

1931

ret = avahi_loop_with_timeout(mc.simple_poll,

1932

(int)(retry_interval * 1000));

2408

1933

if(debug){

2409

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

2410

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

1934

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

1935

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

2411

1936

}

2412

1937

2413

1938

end:

2414

1939

2415

1940

if(debug){

2416

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

1941

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

2417

1942

}

2418

1943

2419

1944

/* Cleanup things */

2420

free(mc.interfaces);

2421

2422

1945

if(sb != NULL)

2423

1946

avahi_s_service_browser_free(sb);

2424

1947

2425

1948

if(mc.server != NULL)

2426

1949

avahi_server_free(mc.server);

2427

1950

2428

if(simple_poll != NULL)

2429

avahi_simple_poll_free(simple_poll);

1951

if(mc.simple_poll != NULL)

1952

avahi_simple_poll_free(mc.simple_poll);

2430

1953

2431

1954

if(gnutls_initialized){

2432

1955

gnutls_certificate_free_credentials(mc.cred);

2437

1960

if(gpgme_initialized){

2438

1961

gpgme_release(mc.ctx);

2439

1962

}

2440

1963

2441

1964

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

2442

1965

has seen */

2443

1966

if(mc.current_server != NULL){

2449

1972

}

2450

1973

}

2451

1974

2452

/* Re-raise priviliges */

2453

{

2454

raise_privileges();

2455

2456

/* Run network hooks */

2457

run_network_hooks("stop", interfaces_hooks != NULL ?

2458

interfaces_hooks : "", delay);

2459

2460

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

2461

{

2462

char *interface = NULL;

2463

while((interface=argz_next(interfaces_to_take_down,

2464

interfaces_to_take_down_size,

2465

interface))){

2466

ret_errno = take_down_interface(interface);

2467

if(ret_errno != 0){

2468

errno = ret_errno;

2469

perror_plus("Failed to take down interface");

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");

1982

}

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");

2470

1992

}

2471

1993

}

2472

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

2473

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

2474

" down\n");

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");

2475

2003

}

2476

2004

}

2477

2478

lower_privileges_permanently();

2479

2005

}

2480

2006

2481

free(interfaces_to_take_down);

2482

free(interfaces_hooks);

2483

2484

2007

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

2485

2008

if(tempdir_created){

2486

2009

struct dirent **direntries = NULL;

2499

2022

}

2500

2023

ret = remove(fullname);

2501

2024

if(ret == -1){

2502

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

2503

strerror(errno));

2025

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

2026

strerror(errno));

2504

2027

}

2505

2028

free(fullname);

2506

2029

}