/mandos/release : revision 237.16.6

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

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#ifndef _LARGEFILE_SOURCE

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#define _LARGEFILE_SOURCE

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#endif /* not _LARGEFILE_SOURCE */

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#endif

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#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

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#endif /* not _FILE_OFFSET_BITS */

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#endif

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

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

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stdout, ferror() */

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

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stdout, ferror(), remove() */

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

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

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

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strtof(), abort() */

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opendir(), DIR */

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

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

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inet_pton(), connect(),

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getnameinfo() */

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

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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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unlinkat() */

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

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char *connect_to = NULL;

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const char *hookdir = HOOKDIR;

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int hookdir_fd = -1;

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uid_t uid = 65534;

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gid_t gid = 65534;

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

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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), nonnull))

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

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va_list ap;

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va_start (ap, format);

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

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program_invocation_short_name));

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

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}

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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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__attribute__((nonnull, warn_unused_result))

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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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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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__attribute__((nonnull, warn_unused_result))

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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, 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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.af = af };

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if(new_server->ip == NULL){

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perror_plus("strdup");

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free(new_server);

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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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#ifdef __GNUC__

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#pragma GCC diagnostic push

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#pragma GCC diagnostic ignored "-Wcast-qual"

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#endif

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

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#ifdef __GNUC__

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#pragma GCC diagnostic pop

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#endif

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free(new_server);

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

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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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__attribute__((nonnull, warn_unused_result))

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static bool init_gpgme(const char * const seckey,

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const char * const pubkey,

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const char * const tempdir,

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mandos_context *mc){

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

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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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bool import_key(const char * const filename){

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bool import_key(const char *filename){

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int ret;

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int fd;

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gpgme_data_t pgp_data;

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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, "Mandos plugin mandos-client: "

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"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, "Mandos plugin mandos-client: "

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"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, "Mandos plugin mandos-client: "

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"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, "Mandos plugin mandos-client: "

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"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, "Mandos plugin mandos-client: "

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"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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}

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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, "Mandos plugin mandos-client: "

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"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" */

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

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

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if(rc != GPG_ERR_NO_ERROR){

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

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

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gpgme_strerror(rc));

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

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

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gpgme_strerror(rc));

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return false;

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}

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* Decrypt OpenPGP data.

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* Returns -1 on error

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*/

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__attribute__((nonnull, warn_unused_result))

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static ssize_t pgp_packet_decrypt(const char *cryptotext,

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size_t crypto_size,

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char **plaintext,

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mandos_context *mc){

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char **plaintext){

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gpgme_data_t dh_crypto, dh_plain;

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gpgme_error_t rc;

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ssize_t ret;

379

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ssize_t plaintext_length = 0;

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if(debug){

382

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

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

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"Trying to decrypt OpenPGP data\n");

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}

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

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rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

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0);

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if(rc != GPG_ERR_NO_ERROR){

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return -1;

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}

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

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rc = gpgme_data_new(&dh_plain);

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if(rc != GPG_ERR_NO_ERROR){

397

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

398

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

399

gpgme_strsource(rc), gpgme_strerror(rc));

362

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

363

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

364

gpgme_strsource(rc), gpgme_strerror(rc));

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gpgme_data_release(dh_crypto);

401

366

return -1;

402

367

}

403

368

404

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

405

370

data buffer */

406

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

371

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

407

372

if(rc != GPG_ERR_NO_ERROR){

408

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

409

gpgme_strsource(rc), gpgme_strerror(rc));

373

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

374

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

375

gpgme_strsource(rc), gpgme_strerror(rc));

410

376

plaintext_length = -1;

411

377

if(debug){

412

378

gpgme_decrypt_result_t result;

413

result = gpgme_op_decrypt_result(mc->ctx);

379

result = gpgme_op_decrypt_result(mc.ctx);

414

380

if(result == NULL){

415

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

381

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

382

"gpgme_op_decrypt_result failed\n");

416

383

} else {

417

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

418

result->unsupported_algorithm);

419

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

420

result->wrong_key_usage);

384

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

385

"Unsupported algorithm: %s\n",

386

result->unsupported_algorithm);

387

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

388

"Wrong key usage: %u\n",

389

result->wrong_key_usage);

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390

if(result->file_name != NULL){

422

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

391

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

392

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

423

393

}

424

394

gpgme_recipient_t recipient;

425

395

recipient = result->recipients;

426

396

while(recipient != NULL){

427

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

428

gpgme_pubkey_algo_name

429

(recipient->pubkey_algo));

430

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

431

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

432

recipient->status == GPG_ERR_NO_SECKEY

433

? "No" : "Yes");

397

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

398

"Public key algorithm: %s\n",

399

gpgme_pubkey_algo_name(recipient->pubkey_algo));

400

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

401

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

402

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

403

"Secret key available: %s\n",

404

recipient->status == GPG_ERR_NO_SECKEY

405

? "No" : "Yes");

434

406

recipient = recipient->next;

435

407

}

436

408

}

439

411

}

440

412

441

413

if(debug){

442

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

414

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

415

"Decryption of OpenPGP data succeeded\n");

443

416

}

444

417

445

418

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

476

449

}

477

450

478

451

if(debug){

479

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

452

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

453

"Decrypted password is: ");

480

454

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

481

455

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

482

456

}

493

467

return plaintext_length;

494

468

}

495

469

496

__attribute__((warn_unused_result))

497

static const char *safer_gnutls_strerror(int value){

498

const char *ret = gnutls_strerror(value);

470

static const char * safer_gnutls_strerror(int value){

471

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

472

-Wunreachable-code */

499

473

if(ret == NULL)

500

474

ret = "(unknown)";

501

475

return ret;

502

476

}

503

477

504

478

/* GnuTLS log function callback */

505

__attribute__((nonnull))

506

479

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

507

480

const char* string){

508

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

481

fprintf(stderr, "Mandos plugin mandos-client: GnuTLS: %s", string);

509

482

}

510

483

511

__attribute__((nonnull, warn_unused_result))

512

484

static int init_gnutls_global(const char *pubkeyfilename,

513

const char *seckeyfilename,

514

mandos_context *mc){

485

const char *seckeyfilename){

515

486

int ret;

516

487

517

488

if(debug){

518

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

489

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

490

"Initializing GnuTLS\n");

519

491

}

520

492

521

493

ret = gnutls_global_init();

522

494

if(ret != GNUTLS_E_SUCCESS){

523

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

524

safer_gnutls_strerror(ret));

495

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

496

"GnuTLS global_init: %s\n", safer_gnutls_strerror(ret));

525

497

return -1;

526

498

}

527

499

534

506

}

535

507

536

508

/* OpenPGP credentials */

537

ret = gnutls_certificate_allocate_credentials(&mc->cred);

509

ret = gnutls_certificate_allocate_credentials(&mc.cred);

538

510

if(ret != GNUTLS_E_SUCCESS){

539

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

540

safer_gnutls_strerror(ret));

511

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

512

"GnuTLS memory error: %s\n", safer_gnutls_strerror(ret));

541

513

gnutls_global_deinit();

542

514

return -1;

543

515

}

544

516

545

517

if(debug){

546

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

547

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

548

pubkeyfilename,

549

seckeyfilename);

518

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

519

"Attempting to use OpenPGP public key %s and"

520

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

521

seckeyfilename);

550

522

}

551

523

552

524

ret = gnutls_certificate_set_openpgp_key_file

553

(mc->cred, pubkeyfilename, seckeyfilename,

525

(mc.cred, pubkeyfilename, seckeyfilename,

554

526

GNUTLS_OPENPGP_FMT_BASE64);

555

527

if(ret != GNUTLS_E_SUCCESS){

556

fprintf_plus(stderr,

557

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

558

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

559

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

560

safer_gnutls_strerror(ret));

528

fprintf(stderr,

529

"Mandos plugin mandos-client: "

530

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

531

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

532

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

533

"The GnuTLS error is: %s\n", safer_gnutls_strerror(ret));

561

534

goto globalfail;

562

535

}

563

536

564

537

/* GnuTLS server initialization */

565

ret = gnutls_dh_params_init(&mc->dh_params);

538

ret = gnutls_dh_params_init(&mc.dh_params);

566

539

if(ret != GNUTLS_E_SUCCESS){

567

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

568

" initialization: %s\n",

569

safer_gnutls_strerror(ret));

540

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

541

"Error in GnuTLS DH parameter initialization:"

542

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

570

543

goto globalfail;

571

544

}

572

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

545

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

573

546

if(ret != GNUTLS_E_SUCCESS){

574

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

575

safer_gnutls_strerror(ret));

547

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

548

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

549

safer_gnutls_strerror(ret));

576

550

goto globalfail;

577

551

}

578

552

579

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

553

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

580

554

581

555

return 0;

582

556

583

557

globalfail:

584

558

585

gnutls_certificate_free_credentials(mc->cred);

559

gnutls_certificate_free_credentials(mc.cred);

586

560

gnutls_global_deinit();

587

gnutls_dh_params_deinit(mc->dh_params);

561

gnutls_dh_params_deinit(mc.dh_params);

588

562

return -1;

589

563

}

590

564

591

__attribute__((nonnull, warn_unused_result))

592

static int init_gnutls_session(gnutls_session_t *session,

593

mandos_context *mc){

565

static int init_gnutls_session(gnutls_session_t *session){

594

566

int ret;

595

567

/* GnuTLS session creation */

596

568

do {

600

572

}

601

573

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

602

574

if(ret != GNUTLS_E_SUCCESS){

603

fprintf_plus(stderr,

604

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

605

safer_gnutls_strerror(ret));

575

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

576

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

577

safer_gnutls_strerror(ret));

606

578

}

607

579

608

580

{

609

581

const char *err;

610

582

do {

611

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

583

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

612

584

if(quit_now){

613

585

gnutls_deinit(*session);

614

586

return -1;

615

587

}

616

588

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

617

589

if(ret != GNUTLS_E_SUCCESS){

618

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

619

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

620

safer_gnutls_strerror(ret));

590

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

591

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

592

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

593

"GnuTLS error: %s\n", safer_gnutls_strerror(ret));

621

594

gnutls_deinit(*session);

622

595

return -1;

623

596

}

625

598

626

599

do {

627

600

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

628

mc->cred);

601

mc.cred);

629

602

if(quit_now){

630

603

gnutls_deinit(*session);

631

604

return -1;

632

605

}

633

606

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

634

607

if(ret != GNUTLS_E_SUCCESS){

635

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

636

safer_gnutls_strerror(ret));

608

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

609

"Error setting GnuTLS credentials: %s\n",

610

safer_gnutls_strerror(ret));

637

611

gnutls_deinit(*session);

638

612

return -1;

639

613

}

641

615

/* ignore client certificate if any. */

642

616

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

643

617

644

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

618

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

645

619

646

620

return 0;

647

621

}

650

624

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

651

625

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

652

626

653

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

654

__attribute__((warn_unused_result))

655

error_t raise_privileges(void){

656

error_t old_errno = errno;

657

error_t ret_errno = 0;

658

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

659

ret_errno = errno;

660

}

661

errno = old_errno;

662

return ret_errno;

663

}

664

665

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

666

__attribute__((warn_unused_result))

667

error_t raise_privileges_permanently(void){

668

error_t old_errno = errno;

669

error_t ret_errno = raise_privileges();

670

if(ret_errno != 0){

671

errno = old_errno;

672

return ret_errno;

673

}

674

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

675

ret_errno = errno;

676

}

677

errno = old_errno;

678

return ret_errno;

679

}

680

681

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

682

__attribute__((warn_unused_result))

683

error_t lower_privileges(void){

684

error_t old_errno = errno;

685

error_t ret_errno = 0;

686

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

687

ret_errno = errno;

688

}

689

errno = old_errno;

690

return ret_errno;

691

}

692

693

/* Lower privileges permanently */

694

__attribute__((warn_unused_result))

695

error_t lower_privileges_permanently(void){

696

error_t old_errno = errno;

697

error_t ret_errno = 0;

698

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

699

ret_errno = errno;

700

}

701

errno = old_errno;

702

return ret_errno;

703

}

704

705

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

706

__attribute__((nonnull, warn_unused_result))

707

static bool add_remove_local_route(const bool add,

708

const char *address,

709

AvahiIfIndex if_index){

710

int ret;

711

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

712

char add_arg[] = "add";

713

char delete_arg[] = "delete";

714

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

715

if(pluginhelperdir == NULL){

716

if(debug){

717

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

718

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

719

}

720

return false;

721

}

722

723

char interface[IF_NAMESIZE];

724

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

725

perror_plus("if_indextoname");

726

return false;

727

}

728

729

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

730

if(devnull == -1){

731

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

732

return false;

733

}

734

pid_t pid = fork();

735

if(pid == 0){

736

/* Child */

737

/* Raise privileges */

738

errno = raise_privileges_permanently();

739

if(errno != 0){

740

perror_plus("Failed to raise privileges");

741

/* _exit(EX_NOPERM); */

742

} else {

743

/* Set group */

744

errno = 0;

745

ret = setgid(0);

746

if(ret == -1){

747

perror_plus("setgid");

748

_exit(EX_NOPERM);

749

}

750

/* Reset supplementary groups */

751

errno = 0;

752

ret = setgroups(0, NULL);

753

if(ret == -1){

754

perror_plus("setgroups");

755

_exit(EX_NOPERM);

756

}

757

}

758

ret = dup2(devnull, STDIN_FILENO);

759

if(ret == -1){

760

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

761

_exit(EX_OSERR);

762

}

763

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

764

if(ret == -1){

765

perror_plus("close");

766

_exit(EX_OSERR);

767

}

768

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

769

if(ret == -1){

770

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

771

_exit(EX_OSERR);

772

}

773

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

774

O_RDONLY

775

| O_DIRECTORY

776

| O_PATH

777

| O_CLOEXEC));

778

if(helperdir_fd == -1){

779

perror_plus("open");

780

_exit(EX_UNAVAILABLE);

781

}

782

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

783

helper, O_RDONLY));

784

if(helper_fd == -1){

785

perror_plus("openat");

786

_exit(EX_UNAVAILABLE);

787

}

788

TEMP_FAILURE_RETRY(close(helperdir_fd));

789

#ifdef __GNUC__

790

#pragma GCC diagnostic push

791

#pragma GCC diagnostic ignored "-Wcast-qual"

792

#endif

793

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

794

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

795

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

796

#ifdef __GNUC__

797

#pragma GCC diagnostic pop

798

#endif

799

perror_plus("fexecve");

800

_exit(EXIT_FAILURE);

801

}

802

}

803

if(pid == -1){

804

perror_plus("fork");

805

return false;

806

}

807

int status;

808

pid_t pret = -1;

809

errno = 0;

810

do {

811

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

812

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

813

int errno_raising = 0;

814

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

815

errno_raising = errno;

816

perror_plus("Failed to raise privileges in order to"

817

" kill helper program");

818

}

819

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

820

perror_plus("kill");

821

}

822

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

823

perror_plus("Failed to lower privileges after killing"

824

" helper program");

825

}

826

return false;

827

}

828

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

829

if(pret == -1){

830

perror_plus("waitpid");

831

return false;

832

}

833

if(WIFEXITED(status)){

834

if(WEXITSTATUS(status) != 0){

835

fprintf_plus(stderr, "Error: iprouteadddel exited"

836

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

837

return false;

838

}

839

return true;

840

}

841

if(WIFSIGNALED(status)){

842

fprintf_plus(stderr, "Error: iprouteadddel died by"

843

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

844

return false;

845

}

846

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

847

return false;

848

}

849

850

__attribute__((nonnull, warn_unused_result))

851

static bool add_local_route(const char *address,

852

AvahiIfIndex if_index){

853

return add_remove_local_route(true, address, if_index);

854

}

855

856

__attribute__((nonnull, warn_unused_result))

857

static bool remove_local_route(const char *address,

858

AvahiIfIndex if_index){

859

return add_remove_local_route(false, address, if_index);

860

}

861

862

627

/* Called when a Mandos server is found */

863

__attribute__((nonnull, warn_unused_result))

864

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

628

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

865

629

AvahiIfIndex if_index,

866

int af, mandos_context *mc){

630

int af){

867

631

int ret, tcp_sd = -1;

868

632

ssize_t sret;

869

struct sockaddr_storage to;

633

union {

634

struct sockaddr_in in;

635

struct sockaddr_in6 in6;

636

} to;

870

637

char *buffer = NULL;

871

638

char *decrypted_buffer = NULL;

872

639

size_t buffer_length = 0;

875

642

int retval = -1;

876

643

gnutls_session_t session;

877

644

int pf; /* Protocol family */

878

bool route_added = false;

879

645

880

646

errno = 0;

881

647

892

658

pf = PF_INET;

893

659

break;

894

660

default:

895

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

661

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

662

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

896

663

errno = EINVAL;

897

664

return -1;

898

665

}

899

666

900

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

901

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

902

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

903

bool match = false;

904

{

905

char *interface = NULL;

906

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

907

interface))){

908

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

909

match = true;

910

break;

911

}

912

}

913

}

914

if(not match){

915

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

916

connect to the server */

917

if(debug){

918

char interface[IF_NAMESIZE];

919

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

920

perror_plus("if_indextoname");

921

} else {

922

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

923

" \"%s\"\n",

924

if_indextoname((unsigned int)if_index,

925

interface));

926

}

927

}

928

return -1;

929

}

930

}

931

932

ret = init_gnutls_session(&session, mc);

667

ret = init_gnutls_session(&session);

933

668

if(ret != 0){

934

669

return -1;

935

670

}

936

671

937

672

if(debug){

938

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

939

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

673

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

674

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

675

"\n", ip, port);

940

676

}

941

677

942

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

678

tcp_sd = socket(pf, SOCK_STREAM, 0);

943

679

if(tcp_sd < 0){

944

680

int e = errno;

945

681

perror_plus("socket");

954

690

955

691

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

956

692

if(af == AF_INET6){

957

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

958

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

693

to.in6.sin6_family = (sa_family_t)af;

694

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

959

695

} else { /* IPv4 */

960

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

961

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

696

to.in.sin_family = (sa_family_t)af;

697

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

962

698

}

963

699

if(ret < 0 ){

964

700

int e = errno;

968

704

}

969

705

if(ret == 0){

970

706

int e = errno;

971

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

707

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

708

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

972

709

errno = e;

973

710

goto mandos_end;

974

711

}

975

712

if(af == AF_INET6){

976

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

977

if(IN6_IS_ADDR_LINKLOCAL

978

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

713

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

714

-Wconversion and

715

-Wunreachable-code */

716

717

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

718

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

719

-Wunreachable-code*/

979

720

if(if_index == AVAHI_IF_UNSPEC){

980

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

981

" incomplete without a network interface\n");

721

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

722

"An IPv6 link-local address is incomplete"

723

" without a network interface\n");

982

724

errno = EINVAL;

983

725

goto mandos_end;

984

726

}

985

727

/* Set the network interface number as scope */

986

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

728

to.in6.sin6_scope_id = (uint32_t)if_index;

987

729

}

988

730

} else {

989

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

731

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

732

-Wconversion and

733

-Wunreachable-code */

990

734

}

991

735

992

736

if(quit_now){

1000

744

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

1001

745

perror_plus("if_indextoname");

1002

746

} else {

1003

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

1004

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

747

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

748

"Connection to: %s%%%s, port %" PRIu16 "\n",

749

ip, interface, port);

1005

750

}

1006

751

} else {

1007

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

1008

ip, (uintmax_t)port);

752

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

753

"Connection to: %s, port %" PRIu16 "\n", ip, port);

1009

754

}

1010

755

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

1011

756

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

1012

if(af == AF_INET6){

1013

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

1014

sizeof(struct sockaddr_in6),

1015

addrstr, sizeof(addrstr), NULL, 0,

1016

NI_NUMERICHOST);

1017

} else {

1018

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

1019

sizeof(struct sockaddr_in),

1020

addrstr, sizeof(addrstr), NULL, 0,

1021

NI_NUMERICHOST);

1022

}

1023

if(ret == EAI_SYSTEM){

1024

perror_plus("getnameinfo");

1025

} else if(ret != 0) {

1026

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

1027

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

1028

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

1029

}

1030

}

1031

1032

if(quit_now){

1033

errno = EINTR;

1034

goto mandos_end;

1035

}

1036

1037

while(true){

1038

if(af == AF_INET6){

1039

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

1040

sizeof(struct sockaddr_in6));

1041

} else {

1042

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

1043

sizeof(struct sockaddr_in));

1044

}

1045

if(ret < 0){

1046

if(errno == ENETUNREACH

1047

and if_index != AVAHI_IF_UNSPEC

1048

and connect_to == NULL

1049

and not route_added and

1050

((af == AF_INET6 and not

1051

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1052

&to)->sin6_addr)))

1053

or (af == AF_INET and

1054

/* Not a a IPv4LL address */

1055

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

1056

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

1057

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

1058

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

1059

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

1060

connect to a Mandos server announced by Avahi on a server

1061

host with a global address. Work around this by retrying

1062

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

1063

1064

Avahi bug reference:

1065

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

1066

https://bugs.debian.org/587961

1067

*/

1068

int e = errno;

1069

route_added = add_local_route(ip, if_index);

1070

if(route_added){

1071

continue;

1072

}

1073

errno = e;

1074

}

1075

if(errno != ECONNREFUSED or debug){

1076

int e = errno;

1077

perror_plus("connect");

1078

errno = e;

1079

}

1080

goto mandos_end;

1081

}

1082

1083

if(quit_now){

1084

errno = EINTR;

1085

goto mandos_end;

1086

}

1087

break;

757

const char *pcret;

758

if(af == AF_INET6){

759

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

760

sizeof(addrstr));

761

} else {

762

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

763

sizeof(addrstr));

764

}

765

if(pcret == NULL){

766

perror_plus("inet_ntop");

767

} else {

768

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

769

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

770

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

771

}

772

}

773

}

774

775

if(quit_now){

776

errno = EINTR;

777

goto mandos_end;

778

}

779

780

if(af == AF_INET6){

781

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

782

} else {

783

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

784

}

785

if(ret < 0){

786

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

787

int e = errno;

788

perror_plus("connect");

789

errno = e;

790

}

791

goto mandos_end;

792

}

793

794

if(quit_now){

795

errno = EINTR;

796

goto mandos_end;

1088

797

}

1089

798

1090

799

const char *out = mandos_protocol_version;

1118

827

}

1119

828

1120

829

if(debug){

1121

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

830

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

831

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

1122

832

}

1123

833

1124

834

if(quit_now){

1126

836

goto mandos_end;

1127

837

}

1128

838

1129

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

1130

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

1131

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

1132

gnutls_transport_set_ptr(session,

1133

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

839

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

840

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1134

841

1135

842

if(quit_now){

1136

843

errno = EINTR;

1147

854

1148

855

if(ret != GNUTLS_E_SUCCESS){

1149

856

if(debug){

1150

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

857

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

858

"*** GnuTLS Handshake failed ***\n");

1151

859

gnutls_perror(ret);

1152

860

}

1153

861

errno = EPROTO;

1157

865

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

1158

866

1159

867

if(debug){

1160

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

1161

" %s\n", ip);

868

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

869

"Retrieving OpenPGP encrypted password from %s\n", ip);

1162

870

}

1163

871

1164

872

while(true){

1202

910

}

1203

911

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

1204

912

if(ret < 0){

1205

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

1206

"***\n");

913

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

914

"*** GnuTLS Re-handshake failed ***\n");

1207

915

gnutls_perror(ret);

1208

916

errno = EPROTO;

1209

917

goto mandos_end;

1210

918

}

1211

919

break;

1212

920

default:

1213

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

1214

" encrypted session with Mandos server\n");

921

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

922

"Unknown error while reading data from"

923

" encrypted session with Mandos server\n");

1215

924

gnutls_bye(session, GNUTLS_SHUT_RDWR);

1216

925

errno = EIO;

1217

926

goto mandos_end;

1222

931

}

1223

932

1224

933

if(debug){

1225

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

934

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

935

"Closing TLS session\n");

1226

936

}

1227

937

1228

938

if(quit_now){

1241

951

if(buffer_length > 0){

1242

952

ssize_t decrypted_buffer_size;

1243

953

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1244

&decrypted_buffer, mc);

954

&decrypted_buffer);

1245

955

if(decrypted_buffer_size >= 0){

1246

956

1247

957

written = 0;

1257

967

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

1258

968

int e = errno;

1259

969

if(debug){

1260

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

1261

strerror(errno));

970

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

971

"Error writing encrypted data: %s\n",

972

strerror(errno));

1262

973

}

1263

974

errno = e;

1264

975

goto mandos_end;

1273

984

1274

985

mandos_end:

1275

986

{

1276

if(route_added){

1277

if(not remove_local_route(ip, if_index)){

1278

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

1279

" interface %d", ip, if_index);

1280

}

1281

}

1282

987

int e = errno;

1283

988

free(decrypted_buffer);

1284

989

free(buffer);

1301

1006

return retval;

1302

1007

}

1303

1008

1304

__attribute__((nonnull))

1305

1009

static void resolve_callback(AvahiSServiceResolver *r,

1306

1010

AvahiIfIndex interface,

1307

1011

AvahiProtocol proto,

1315

1019

AVAHI_GCC_UNUSED AvahiStringList *txt,

1316

1020

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1317

1021

flags,

1318

void *mc){

1319

if(r == NULL){

1320

return;

1321

}

1022

AVAHI_GCC_UNUSED void* userdata){

1023

assert(r);

1322

1024

1323

1025

/* Called whenever a service has been resolved successfully or

1324

1026

timed out */

1325

1027

1326

1028

if(quit_now){

1327

avahi_s_service_resolver_free(r);

1328

1029

return;

1329

1030

}

1330

1031

1331

1032

switch(event){

1332

1033

default:

1333

1034

case AVAHI_RESOLVER_FAILURE:

1334

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

1335

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

1336

domain,

1337

avahi_strerror(avahi_server_errno

1338

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

1035

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

1036

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

1037

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

1038

avahi_strerror(avahi_server_errno(mc.server)));

1339

1039

break;

1340

1040

1341

1041

case AVAHI_RESOLVER_FOUND:

1343

1043

char ip[AVAHI_ADDRESS_STR_MAX];

1344

1044

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

1345

1045

if(debug){

1346

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

1347

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

1348

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

1046

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

1047

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

1048

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

1049

ip, (intmax_t)interface, port);

1349

1050

}

1350

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

1351

interface,

1352

avahi_proto_to_af(proto),

1353

mc);

1051

int ret = start_mandos_communication(ip, port, interface,

1052

avahi_proto_to_af(proto));

1354

1053

if(ret == 0){

1355

avahi_simple_poll_quit(simple_poll);

1054

avahi_simple_poll_quit(mc.simple_poll);

1356

1055

} else {

1357

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

1358

avahi_proto_to_af(proto),

1359

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

1360

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

1361

" list\n", name);

1362

}

1056

ret = add_server(ip, port, interface,

1057

avahi_proto_to_af(proto));

1363

1058

}

1364

1059

}

1365

1060

}

1375

1070

const char *domain,

1376

1071

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1377

1072

flags,

1378

void *mc){

1379

if(b == NULL){

1380

return;

1381

}

1073

AVAHI_GCC_UNUSED void* userdata){

1074

assert(b);

1382

1075

1383

1076

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

1384

1077

is removed from the LAN */

1391

1084

default:

1392

1085

case AVAHI_BROWSER_FAILURE:

1393

1086

1394

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

1395

avahi_strerror(avahi_server_errno

1396

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

1397

avahi_simple_poll_quit(simple_poll);

1087

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

1088

"(Avahi browser) %s\n",

1089

avahi_strerror(avahi_server_errno(mc.server)));

1090

avahi_simple_poll_quit(mc.simple_poll);

1398

1091

return;

1399

1092

1400

1093

case AVAHI_BROWSER_NEW:

1403

1096

the callback function is called the Avahi server will free the

1404

1097

resolver for us. */

1405

1098

1406

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

1407

interface, protocol, name, type,

1408

domain, protocol, 0,

1409

resolve_callback, mc) == NULL)

1410

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

1411

" %s\n", name,

1412

avahi_strerror(avahi_server_errno

1413

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

1099

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

1100

name, type, domain, protocol, 0,

1101

resolve_callback, NULL) == NULL)

1102

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

1103

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

1104

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

1414

1105

break;

1415

1106

1416

1107

case AVAHI_BROWSER_REMOVE:

1419

1110

case AVAHI_BROWSER_ALL_FOR_NOW:

1420

1111

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1421

1112

if(debug){

1422

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

1423

" searching...\n");

1113

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

1114

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

1424

1115

}

1425

1116

break;

1426

1117

}

1435

1126

signal_received = sig;

1436

1127

int old_errno = errno;

1437

1128

/* set main loop to exit */

1438

if(simple_poll != NULL){

1439

avahi_simple_poll_quit(simple_poll);

1129

if(mc.simple_poll != NULL){

1130

avahi_simple_poll_quit(mc.simple_poll);

1440

1131

}

1441

1132

errno = old_errno;

1442

1133

}

1443

1134

1444

__attribute__((nonnull, warn_unused_result))

1445

1135

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

1446

1136

int ret;

1447

error_t ret_errno;

1448

1137

1449

1138

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

1450

1139

if(s < 0){

1451

ret_errno = errno;

1452

1140

perror_plus("socket");

1453

errno = ret_errno;

1454

1141

return false;

1455

1142

}

1456

1143

strcpy(ifr->ifr_name, ifname);

1457

1144

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1458

1145

if(ret == -1){

1459

1146

if(debug){

1460

ret_errno = errno;

1461

1147

perror_plus("ioctl SIOCGIFFLAGS");

1462

errno = ret_errno;

1463

1148

}

1464

1149

return false;

1465

1150

}

1466

1151

return true;

1467

1152

}

1468

1153

1469

__attribute__((nonnull, warn_unused_result))

1470

1154

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

1471

1155

1472

1156

/* Reject the loopback device */

1473

1157

if(ifr->ifr_flags & IFF_LOOPBACK){

1474

1158

if(debug){

1475

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

1476

ifname);

1159

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

1160

"Rejecting loopback interface \"%s\"\n", ifname);

1477

1161

}

1478

1162

return false;

1479

1163

}

1480

1164

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

1481

1165

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

1482

1166

if(debug){

1483

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

1484

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

1167

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

1168

"Accepting point-to-point interface \"%s\"\n", ifname);

1485

1169

}

1486

1170

return true;

1487

1171

}

1488

1172

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

1489

1173

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

1490

1174

if(debug){

1491

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1492

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

1175

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

1176

"Rejecting non-broadcast interface \"%s\"\n", ifname);

1493

1177

}

1494

1178

return false;

1495

1179

}

1496

1180

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

1497

1181

if(ifr->ifr_flags & IFF_NOARP){

1498

1182

if(debug){

1499

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

1500

ifname);

1183

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

1184

"Rejecting non-ARP interface \"%s\"\n", ifname);

1501

1185

}

1502

1186

return false;

1503

1187

}

1504

1188

1505

1189

/* Accept this device */

1506

1190

if(debug){

1507

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

1191

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

1192

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

1508

1193

}

1509

1194

return true;

1510

1195

}

1514

1199

* corresponds to an acceptable network device.

1515

1200

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

1516

1201

*/

1517

__attribute__((nonnull, warn_unused_result))

1518

1202

int good_interface(const struct dirent *if_entry){

1519

1203

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

1520

1204

return 0;

1523

1207

struct ifreq ifr;

1524

1208

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

1525

1209

if(debug){

1526

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

1527

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

1528

}

1529

return 0;

1530

}

1531

1532

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

1533

return 0;

1534

}

1535

return 1;

1536

}

1537

1538

/*

1539

* This function determines if a network interface is up.

1540

*/

1541

__attribute__((nonnull, warn_unused_result))

1542

bool interface_is_up(const char *interface){

1543

struct ifreq ifr;

1544

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

1545

if(debug){

1546

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

1547

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

1548

}

1549

return false;

1550

}

1551

1552

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

1553

}

1554

1555

/*

1556

* This function determines if a network interface is running

1557

*/

1558

__attribute__((nonnull, warn_unused_result))

1559

bool interface_is_running(const char *interface){

1560

struct ifreq ifr;

1561

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

1562

if(debug){

1563

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

1564

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

1565

}

1566

return false;

1567

}

1568

1569

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

1570

}

1571

1572

__attribute__((nonnull, pure, warn_unused_result))

1210

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

1211

"Failed to get flags for interface \"%s\"\n",

1212

if_entry->d_name);

1213

}

1214

return 0;

1215

}

1216

1217

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

1218

return 0;

1219

}

1220

return 1;

1221

}

1222

1223

/*

1224

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

1225

* corresponds to an acceptable network device which is up.

1226

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

1227

*/

1228

int up_interface(const struct dirent *if_entry){

1229

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

1230

return 0;

1231

}

1232

1233

struct ifreq ifr;

1234

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

1235

if(debug){

1236

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

1237

"Failed to get flags for interface \"%s\"\n",

1238

if_entry->d_name);

1239

}

1240

return 0;

1241

}

1242

1243

/* Reject down interfaces */

1244

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

1245

if(debug){

1246

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

1247

"Rejecting down interface \"%s\"\n",

1248

if_entry->d_name);

1249

}

1250

return 0;

1251

}

1252

1253

/* Reject non-running interfaces */

1254

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

1255

if(debug){

1256

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

1257

"Rejecting non-running interface \"%s\"\n",

1258

if_entry->d_name);

1259

}

1260

return 0;

1261

}

1262

1263

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

1264

return 0;

1265

}

1266

return 1;

1267

}

1268

1573

1269

int notdotentries(const struct dirent *direntry){

1574

1270

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

1575

1271

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

1582

1278

}

1583

1279

1584

1280

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

1585

__attribute__((nonnull, warn_unused_result))

1586

1281

int runnable_hook(const struct dirent *direntry){

1587

1282

int ret;

1588

1283

size_t sret;

1596

1291

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

1597

1292

"abcdefghijklmnopqrstuvwxyz"

1598

1293

"0123456789"

1599

"_.-");

1294

"_-");

1600

1295

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

1601

1296

/* Contains non-allowed characters */

1602

1297

if(debug){

1603

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

1604

direntry->d_name);

1298

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

1299

"Ignoring hook \"%s\" with bad name\n",

1300

direntry->d_name);

1605

1301

}

1606

1302

return 0;

1607

1303

}

1608

1304

1609

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

1305

char *fullname = NULL;

1306

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

1307

if(ret < 0){

1308

perror_plus("asprintf");

1309

return 0;

1310

}

1311

1312

ret = stat(fullname, &st);

1610

1313

if(ret == -1){

1611

1314

if(debug){

1612

1315

perror_plus("Could not stat hook");

1616

1319

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

1617

1320

/* Not a regular file */

1618

1321

if(debug){

1619

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

1620

direntry->d_name);

1322

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

1323

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

1324

direntry->d_name);

1621

1325

}

1622

1326

return 0;

1623

1327

}

1624

1328

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

1625

1329

/* Not executable */

1626

1330

if(debug){

1627

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

1628

direntry->d_name);

1331

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

1332

"Ignoring hook \"%s\" - not executable\n",

1333

direntry->d_name);

1629

1334

}

1630

1335

return 0;

1631

1336

}

1632

if(debug){

1633

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

1634

direntry->d_name);

1635

}

1636

1337

return 1;

1637

1338

}

1638

1339

1639

__attribute__((nonnull, warn_unused_result))

1640

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1641

mandos_context *mc){

1340

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1642

1341

int ret;

1643

1342

struct timespec now;

1644

1343

struct timespec waited_time;

1645

1344

intmax_t block_time;

1646

1345

1647

1346

while(true){

1648

if(mc->current_server == NULL){

1649

if(debug){

1650

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

1651

" No timeout!\n");

1347

if(mc.current_server == NULL){

1348

if (debug){

1349

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

1350

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

1652

1351

}

1653

1352

ret = avahi_simple_poll_iterate(s, -1);

1654

1353

} else {

1655

if(debug){

1656

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

1657

" it, or wait\n");

1354

if (debug){

1355

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

1356

"Check current_server if we should run it,"

1357

" or wait\n");

1658

1358

}

1659

1359

/* the current time */

1660

1360

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1665

1365

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

1666

1366

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

1667

1367

waited_time.tv_sec = (now.tv_sec

1668

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

1368

- mc.current_server->last_seen.tv_sec);

1669

1369

waited_time.tv_nsec = (now.tv_nsec

1670

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

1370

- mc.current_server->last_seen.tv_nsec);

1671

1371

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

1672

1372

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

1673

1373

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

1675

1375

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

1676

1376

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

1677

1377

1678

if(debug){

1679

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

1680

block_time);

1378

if (debug){

1379

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

1380

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

1681

1381

}

1682

1382

1683

1383

if(block_time <= 0){

1684

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

1685

mc->current_server->port,

1686

mc->current_server->if_index,

1687

mc->current_server->af, mc);

1384

ret = start_mandos_communication(mc.current_server->ip,

1385

mc.current_server->port,

1386

mc.current_server->if_index,

1387

mc.current_server->af);

1688

1388

if(ret == 0){

1689

avahi_simple_poll_quit(s);

1389

avahi_simple_poll_quit(mc.simple_poll);

1690

1390

return 0;

1691

1391

}

1692

1392

ret = clock_gettime(CLOCK_MONOTONIC,

1693

&mc->current_server->last_seen);

1393

&mc.current_server->last_seen);

1694

1394

if(ret == -1){

1695

1395

perror_plus("clock_gettime");

1696

1396

return -1;

1697

1397

}

1698

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

1398

mc.current_server = mc.current_server->next;

1699

1399

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

1700

1400

servers, but don't block */

1701

1401

}

1703

1403

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

1704

1404

}

1705

1405

if(ret != 0){

1706

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

1406

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

1707

1407

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

1708

1408

}

1709

1409

}

1710

1410

}

1711

1411

}

1712

1412

1713

__attribute__((nonnull))

1714

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

1715

const float delay){

1716

struct dirent **direntries = NULL;

1717

if(hookdir_fd == -1){

1718

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1719

| O_CLOEXEC);

1720

if(hookdir_fd == -1){

1721

if(errno == ENOENT){

1722

if(debug){

1723

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

1724

" found\n", hookdir);

1725

}

1726

} else {

1727

perror_plus("open");

1728

}

1729

return;

1730

}

1731

}

1732

#ifdef __GLIBC__

1733

#if __GLIBC_PREREQ(2, 15)

1734

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

1735

runnable_hook, alphasort);

1736

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

1737

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

1738

alphasort);

1739

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

1740

#else /* not __GLIBC__ */

1741

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

1742

alphasort);

1743

#endif /* not __GLIBC__ */

1744

if(numhooks == -1){

1745

perror_plus("scandir");

1746

return;

1747

}

1748

struct dirent *direntry;

1749

int ret;

1750

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

1751

if(devnull == -1){

1752

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

1753

return;

1754

}

1755

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

1756

direntry = direntries[i];

1757

if(debug){

1758

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

1759

direntry->d_name);

1760

}

1761

pid_t hook_pid = fork();

1762

if(hook_pid == 0){

1763

/* Child */

1764

/* Raise privileges */

1765

errno = raise_privileges_permanently();

1766

if(errno != 0){

1767

perror_plus("Failed to raise privileges");

1768

_exit(EX_NOPERM);

1769

}

1770

/* Set group */

1771

errno = 0;

1772

ret = setgid(0);

1773

if(ret == -1){

1774

perror_plus("setgid");

1775

_exit(EX_NOPERM);

1776

}

1777

/* Reset supplementary groups */

1778

errno = 0;

1779

ret = setgroups(0, NULL);

1780

if(ret == -1){

1781

perror_plus("setgroups");

1782

_exit(EX_NOPERM);

1783

}

1784

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

1785

if(ret == -1){

1786

perror_plus("setenv");

1787

_exit(EX_OSERR);

1788

}

1789

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

1790

if(ret == -1){

1791

perror_plus("setenv");

1792

_exit(EX_OSERR);

1793

}

1794

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

1795

if(ret == -1){

1796

perror_plus("setenv");

1797

_exit(EX_OSERR);

1798

}

1799

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

1800

if(ret == -1){

1801

perror_plus("setenv");

1802

_exit(EX_OSERR);

1803

}

1804

char *delaystring;

1805

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

1806

if(ret == -1){

1807

perror_plus("asprintf");

1808

_exit(EX_OSERR);

1809

}

1810

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

1811

if(ret == -1){

1812

free(delaystring);

1813

perror_plus("setenv");

1814

_exit(EX_OSERR);

1815

}

1816

free(delaystring);

1817

if(connect_to != NULL){

1818

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

1819

if(ret == -1){

1820

perror_plus("setenv");

1821

_exit(EX_OSERR);

1822

}

1823

}

1824

int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,

1825

direntry->d_name,

1826

O_RDONLY));

1827

if(hook_fd == -1){

1828

perror_plus("openat");

1829

_exit(EXIT_FAILURE);

1830

}

1831

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

1832

perror_plus("close");

1833

_exit(EXIT_FAILURE);

1834

}

1835

ret = dup2(devnull, STDIN_FILENO);

1836

if(ret == -1){

1837

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

1838

_exit(EX_OSERR);

1839

}

1840

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

1841

if(ret == -1){

1842

perror_plus("close");

1843

_exit(EX_OSERR);

1844

}

1845

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1846

if(ret == -1){

1847

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

1848

_exit(EX_OSERR);

1849

}

1850

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

1851

environ) == -1){

1852

perror_plus("fexecve");

1853

_exit(EXIT_FAILURE);

1854

}

1855

} else {

1856

if(hook_pid == -1){

1857

perror_plus("fork");

1858

free(direntry);

1859

continue;

1860

}

1861

int status;

1862

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

1863

perror_plus("waitpid");

1864

free(direntry);

1865

continue;

1866

}

1867

if(WIFEXITED(status)){

1868

if(WEXITSTATUS(status) != 0){

1869

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

1870

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

1871

WEXITSTATUS(status));

1872

free(direntry);

1873

continue;

1874

}

1875

} else if(WIFSIGNALED(status)){

1876

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

1877

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

1878

WTERMSIG(status));

1879

free(direntry);

1880

continue;

1881

} else {

1882

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

1883

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

1884

free(direntry);

1885

continue;

1886

}

1887

}

1888

if(debug){

1889

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

1890

direntry->d_name);

1891

}

1892

free(direntry);

1893

}

1894

free(direntries);

1895

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

1896

perror_plus("close");

1897

} else {

1898

hookdir_fd = -1;

1899

}

1900

close(devnull);

1901

}

1902

1903

__attribute__((nonnull, warn_unused_result))

1904

error_t bring_up_interface(const char *const interface,

1905

const float delay){

1906

error_t old_errno = errno;

1907

int ret;

1908

struct ifreq network;

1909

unsigned int if_index = if_nametoindex(interface);

1910

if(if_index == 0){

1911

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

1912

errno = old_errno;

1913

return ENXIO;

1914

}

1915

1916

if(quit_now){

1917

errno = old_errno;

1918

return EINTR;

1919

}

1920

1921

if(not interface_is_up(interface)){

1922

error_t ret_errno = 0, ioctl_errno = 0;

1923

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

1924

ret_errno = errno;

1925

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

1926

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

1927

errno = old_errno;

1928

return ret_errno;

1929

}

1930

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

1931

1932

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

1933

if(sd == -1){

1934

ret_errno = errno;

1935

perror_plus("socket");

1936

errno = old_errno;

1937

return ret_errno;

1938

}

1939

1940

if(quit_now){

1941

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

1942

if(ret == -1){

1943

perror_plus("close");

1944

}

1945

errno = old_errno;

1946

return EINTR;

1947

}

1948

1949

if(debug){

1950

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

1951

interface);

1952

}

1953

1954

/* Raise privileges */

1955

ret_errno = raise_privileges();

1956

if(ret_errno != 0){

1957

errno = ret_errno;

1958

perror_plus("Failed to raise privileges");

1959

}

1960

1961

#ifdef __linux__

1962

int ret_linux;

1963

bool restore_loglevel = false;

1964

if(ret_errno == 0){

1965

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1966

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

1967

ret_linux = klogctl(8, NULL, 5);

1968

if(ret_linux == -1){

1969

perror_plus("klogctl");

1970

} else {

1971

restore_loglevel = true;

1972

}

1973

}

1974

#endif /* __linux__ */

1975

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

1976

ioctl_errno = errno;

1977

#ifdef __linux__

1978

if(restore_loglevel){

1979

ret_linux = klogctl(7, NULL, 0);

1980

if(ret_linux == -1){

1981

perror_plus("klogctl");

1982

}

1983

}

1984

#endif /* __linux__ */

1985

1986

/* If raise_privileges() succeeded above */

1987

if(ret_errno == 0){

1988

/* Lower privileges */

1989

ret_errno = lower_privileges();

1990

if(ret_errno != 0){

1991

errno = ret_errno;

1992

perror_plus("Failed to lower privileges");

1993

}

1994

}

1995

1996

/* Close the socket */

1997

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

1998

if(ret == -1){

1999

perror_plus("close");

2000

}

2001

2002

if(ret_setflags == -1){

2003

errno = ioctl_errno;

2004

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2005

errno = old_errno;

2006

return ioctl_errno;

2007

}

2008

} else if(debug){

2009

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

2010

interface);

2011

}

2012

2013

/* Sleep checking until interface is running.

2014

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

2015

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

2016

if(interface_is_running(interface)){

2017

break;

2018

}

2019

struct timespec sleeptime = { .tv_nsec = 250000000 };

2020

ret = nanosleep(&sleeptime, NULL);

2021

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

2022

perror_plus("nanosleep");

2023

}

2024

}

2025

2026

errno = old_errno;

2027

return 0;

2028

}

2029

2030

__attribute__((nonnull, warn_unused_result))

2031

error_t take_down_interface(const char *const interface){

2032

error_t old_errno = errno;

2033

struct ifreq network;

2034

unsigned int if_index = if_nametoindex(interface);

2035

if(if_index == 0){

2036

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

2037

errno = old_errno;

2038

return ENXIO;

2039

}

2040

if(interface_is_up(interface)){

2041

error_t ret_errno = 0, ioctl_errno = 0;

2042

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

2043

ret_errno = errno;

2044

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

2045

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

2046

errno = old_errno;

2047

return ret_errno;

2048

}

2049

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

2050

2051

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

2052

if(sd == -1){

2053

ret_errno = errno;

2054

perror_plus("socket");

2055

errno = old_errno;

2056

return ret_errno;

2057

}

2058

2059

if(debug){

2060

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

2061

interface);

2062

}

2063

2064

/* Raise privileges */

2065

ret_errno = raise_privileges();

2066

if(ret_errno != 0){

2067

errno = ret_errno;

2068

perror_plus("Failed to raise privileges");

2069

}

2070

2071

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

2072

ioctl_errno = errno;

2073

2074

/* If raise_privileges() succeeded above */

2075

if(ret_errno == 0){

2076

/* Lower privileges */

2077

ret_errno = lower_privileges();

2078

if(ret_errno != 0){

2079

errno = ret_errno;

2080

perror_plus("Failed to lower privileges");

2081

}

2082

}

2083

2084

/* Close the socket */

2085

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

2086

if(ret == -1){

2087

perror_plus("close");

2088

}

2089

2090

if(ret_setflags == -1){

2091

errno = ioctl_errno;

2092

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2093

errno = old_errno;

2094

return ioctl_errno;

2095

}

2096

} else if(debug){

2097

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

2098

interface);

2099

}

2100

2101

errno = old_errno;

2102

return 0;

2103

}

2104

2105

1413

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

2106

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

2107

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

2108

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

2109

.interfaces = NULL, .interfaces_size = 0 };

2110

1414

AvahiSServiceBrowser *sb = NULL;

2111

error_t ret_errno;

1415

int error;

2112

1416

int ret;

2113

1417

intmax_t tmpmax;

2114

1418

char *tmp;

2115

1419

int exitcode = EXIT_SUCCESS;

2116

char *interfaces_to_take_down = NULL;

2117

size_t interfaces_to_take_down_size = 0;

2118

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

2119

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

2120

char *tempdir = NULL;

1420

const char *interface = "";

1421

struct ifreq network;

1422

int sd = -1;

1423

bool take_down_interface = false;

1424

uid_t uid;

1425

gid_t gid;

1426

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

1427

bool tempdir_created = false;

2121

1428

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2122

1429

const char *seckey = PATHDIR "/" SECKEY;

2123

1430

const char *pubkey = PATHDIR "/" PUBKEY;

2124

char *interfaces_hooks = NULL;

2125

1431

2126

1432

bool gnutls_initialized = false;

2127

1433

bool gpgme_initialized = false;

2189

1495

.group = 2 },

2190

1496

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

2191

1497

.arg = "SECONDS",

2192

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

1498

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

2193

1499

.group = 2 },

2194

1500

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

2195

1501

.arg = "DIR",

2218

1524

connect_to = arg;

2219

1525

break;

2220

1526

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

2221

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

2222

arg, (int)',');

2223

if(ret_errno != 0){

2224

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

2225

}

1527

interface = arg;

2226

1528

break;

2227

1529

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

2228

1530

seckey = arg;

2271

1573

argp_state_help(state, state->out_stream,

2272

1574

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2273

1575

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

2274

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

1576

fprintf(state->out_stream, "Mandos plugin mandos-client: ");

1577

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

2275

1578

exit(argp_err_exit_status);

2276

1579

break;

2277

1580

default:

2300

1603

goto end;

2301

1604

}

2302

1605

}

2303

1606

2304

1607

{

2305

1608

/* Work around Debian bug #633582:

2306

1609

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

2307

2308

/* Re-raise privileges */

2309

ret_errno = raise_privileges();

2310

if(ret_errno != 0){

2311

errno = ret_errno;

2312

perror_plus("Failed to raise privileges");

1610

struct stat st;

1611

1612

/* Re-raise priviliges */

1613

errno = 0;

1614

ret = seteuid(0);

1615

if(ret == -1){

1616

perror_plus("seteuid");

1617

}

1618

1619

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

1620

int seckey_fd = open(seckey, O_RDONLY);

1621

if(seckey_fd == -1){

1622

perror_plus("open");

1623

} else {

1624

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

1625

if(ret == -1){

1626

perror_plus("fstat");

1627

} else {

1628

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

1629

ret = fchown(seckey_fd, uid, gid);

1630

if(ret == -1){

1631

perror_plus("fchown");

1632

}

1633

}

1634

}

1635

TEMP_FAILURE_RETRY(close(seckey_fd));

1636

}

1637

}

1638

1639

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

1640

int pubkey_fd = open(pubkey, O_RDONLY);

1641

if(pubkey_fd == -1){

1642

perror_plus("open");

1643

} else {

1644

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

1645

if(ret == -1){

1646

perror_plus("fstat");

1647

} else {

1648

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

1649

ret = fchown(pubkey_fd, uid, gid);

1650

if(ret == -1){

1651

perror_plus("fchown");

1652

}

1653

}

1654

}

1655

TEMP_FAILURE_RETRY(close(pubkey_fd));

1656

}

1657

}

1658

1659

/* Lower privileges */

1660

errno = 0;

1661

ret = seteuid(uid);

1662

if(ret == -1){

1663

perror_plus("seteuid");

1664

}

1665

}

1666

1667

/* Find network hooks and run them */

1668

{

1669

struct dirent **direntries;

1670

struct dirent *direntry;

1671

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

1672

alphasort);

1673

if(numhooks == -1){

1674

perror_plus("scandir");

2313

1675

} else {

2314

struct stat st;

2315

2316

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

2317

int seckey_fd = open(seckey, O_RDONLY);

2318

if(seckey_fd == -1){

2319

perror_plus("open");

2320

} else {

2321

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

2322

if(ret == -1){

2323

perror_plus("fstat");

2324

} else {

2325

if(S_ISREG(st.st_mode)

2326

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

2327

ret = fchown(seckey_fd, uid, gid);

2328

if(ret == -1){

2329

perror_plus("fchown");

2330

}

2331

}

2332

}

2333

TEMP_FAILURE_RETRY(close(seckey_fd));

2334

}

2335

}

2336

2337

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

2338

int pubkey_fd = open(pubkey, O_RDONLY);

2339

if(pubkey_fd == -1){

2340

perror_plus("open");

2341

} else {

2342

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

2343

if(ret == -1){

2344

perror_plus("fstat");

2345

} else {

2346

if(S_ISREG(st.st_mode)

2347

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

2348

ret = fchown(pubkey_fd, uid, gid);

2349

if(ret == -1){

2350

perror_plus("fchown");

2351

}

2352

}

2353

}

2354

TEMP_FAILURE_RETRY(close(pubkey_fd));

2355

}

2356

}

2357

2358

/* Lower privileges */

2359

ret_errno = lower_privileges();

2360

if(ret_errno != 0){

2361

errno = ret_errno;

2362

perror_plus("Failed to lower privileges");

2363

}

2364

}

2365

}

2366

2367

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

2368

{

2369

char *interface = NULL;

2370

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

2371

interface))){

2372

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

2373

and if_nametoindex(interface) == 0){

2374

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

2375

fprintf_plus(stderr, "Not using nonexisting interface"

2376

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

2377

}

2378

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

2379

interface = NULL;

2380

}

2381

}

2382

}

2383

2384

/* Run network hooks */

2385

{

2386

if(mc.interfaces != NULL){

2387

interfaces_hooks = malloc(mc.interfaces_size);

2388

if(interfaces_hooks == NULL){

2389

perror_plus("malloc");

2390

goto end;

2391

}

2392

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

2393

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

2394

}

2395

run_network_hooks("start", interfaces_hooks != NULL ?

2396

interfaces_hooks : "", delay);

1676

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

1677

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

1678

direntry = direntries[0];

1679

char *fullname = NULL;

1680

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

1681

if(ret < 0){

1682

perror_plus("asprintf");

1683

continue;

1684

}

1685

pid_t hook_pid = fork();

1686

if(hook_pid == 0){

1687

/* Child */

1688

dup2(devnull, STDIN_FILENO);

1689

close(devnull);

1690

dup2(STDERR_FILENO, STDOUT_FILENO);

1691

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

1692

if(ret == -1){

1693

perror_plus("setenv");

1694

exit(1);

1695

}

1696

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

1697

if(ret == -1){

1698

perror_plus("setenv");

1699

exit(1);

1700

}

1701

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

1702

if(ret == -1){

1703

perror_plus("setenv");

1704

exit(1);

1705

}

1706

char *delaystring;

1707

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

1708

if(ret == -1){

1709

perror_plus("asprintf");

1710

exit(1);

1711

}

1712

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

1713

if(ret == -1){

1714

free(delaystring);

1715

perror_plus("setenv");

1716

exit(1);

1717

}

1718

free(delaystring);

1719

ret = execl(fullname, direntry->d_name, "start", NULL);

1720

perror_plus("execl");

1721

} else {

1722

int status;

1723

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

1724

perror_plus("waitpid");

1725

free(fullname);

1726

continue;

1727

}

1728

if(WIFEXITED(status)){

1729

if(WEXITSTATUS(status) != 0){

1730

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

1731

"Warning: network hook \"%s\" exited"

1732

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

1733

WEXITSTATUS(status));

1734

free(fullname);

1735

continue;

1736

}

1737

} else if(WIFSIGNALED(status)){

1738

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

1739

"Warning: network hook \"%s\" died by"

1740

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

1741

WTERMSIG(status));

1742

free(fullname);

1743

continue;

1744

} else {

1745

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

1746

"Warning: network hook \"%s\" crashed\n",

1747

direntry->d_name);

1748

free(fullname);

1749

continue;

1750

}

1751

}

1752

free(fullname);

1753

if(quit_now){

1754

goto end;

1755

}

1756

}

1757

close(devnull);

1758

}

2397

1759

}

2398

1760

2399

1761

if(not debug){

2400

1762

avahi_set_log_function(empty_log);

2401

1763

}

2402

1764

1765

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

1766

struct dirent **direntries;

1767

/* First look for interfaces that are up */

1768

ret = scandir(sys_class_net, &direntries, up_interface,

1769

alphasort);

1770

if(ret == 0){

1771

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

1772

free(direntries);

1773

ret = scandir(sys_class_net, &direntries, good_interface,

1774

alphasort);

1775

}

1776

if(ret >= 1){

1777

/* Pick the first interface returned */

1778

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

1779

if(debug){

1780

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

1781

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

1782

}

1783

if(interface == NULL){

1784

perror_plus("malloc");

1785

free(direntries);

1786

exitcode = EXIT_FAILURE;

1787

goto end;

1788

}

1789

free(direntries);

1790

} else {

1791

free(direntries);

1792

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

1793

"Could not find a network interface\n");

1794

exitcode = EXIT_FAILURE;

1795

goto end;

1796

}

1797

}

1798

2403

1799

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

2404

1800

from the signal handler */

2405

1801

/* Initialize the pseudo-RNG for Avahi */

2406

1802

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

2407

simple_poll = avahi_simple_poll_new();

2408

if(simple_poll == NULL){

2409

fprintf_plus(stderr,

2410

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

1803

mc.simple_poll = avahi_simple_poll_new();

1804

if(mc.simple_poll == NULL){

1805

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

1806

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

2411

1807

exitcode = EX_UNAVAILABLE;

2412

1808

goto end;

2413

1809

}

2475

1871

}

2476

1872

}

2477

1873

2478

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

2479

if(mc.interfaces == NULL){

2480

struct dirent **direntries = NULL;

2481

/* Look for any good interfaces */

2482

ret = scandir(sys_class_net, &direntries, good_interface,

2483

alphasort);

2484

if(ret >= 1){

2485

/* Add all found interfaces to interfaces list */

2486

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

2487

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

2488

direntries[i]->d_name);

2489

if(ret_errno != 0){

2490

errno = ret_errno;

2491

perror_plus("argz_add");

2492

free(direntries[i]);

2493

continue;

2494

}

2495

if(debug){

2496

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

2497

direntries[i]->d_name);

2498

}

2499

free(direntries[i]);

2500

}

2501

free(direntries);

1874

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

1875

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

1876

if_index = (AvahiIfIndex) if_nametoindex(interface);

1877

if(if_index == 0){

1878

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

1879

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

1880

exitcode = EX_UNAVAILABLE;

1881

goto end;

1882

}

1883

1884

if(quit_now){

1885

goto end;

1886

}

1887

1888

/* Re-raise priviliges */

1889

errno = 0;

1890

ret = seteuid(0);

1891

if(ret == -1){

1892

perror_plus("seteuid");

1893

}

1894

1895

#ifdef __linux__

1896

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1897

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

1898

ret = klogctl(8, NULL, 5);

1899

bool restore_loglevel = true;

1900

if(ret == -1){

1901

restore_loglevel = false;

1902

perror_plus("klogctl");

1903

}

1904

#endif /* __linux__ */

1905

1906

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1907

if(sd < 0){

1908

perror_plus("socket");

1909

exitcode = EX_OSERR;

1910

#ifdef __linux__

1911

if(restore_loglevel){

1912

ret = klogctl(7, NULL, 0);

1913

if(ret == -1){

1914

perror_plus("klogctl");

1915

}

1916

}

1917

#endif /* __linux__ */

1918

/* Lower privileges */

1919

errno = 0;

1920

ret = seteuid(uid);

1921

if(ret == -1){

1922

perror_plus("seteuid");

1923

}

1924

goto end;

1925

}

1926

strcpy(network.ifr_name, interface);

1927

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

1928

if(ret == -1){

1929

perror_plus("ioctl SIOCGIFFLAGS");

1930

#ifdef __linux__

1931

if(restore_loglevel){

1932

ret = klogctl(7, NULL, 0);

1933

if(ret == -1){

1934

perror_plus("klogctl");

1935

}

1936

}

1937

#endif /* __linux__ */

1938

exitcode = EX_OSERR;

1939

/* Lower privileges */

1940

errno = 0;

1941

ret = seteuid(uid);

1942

if(ret == -1){

1943

perror_plus("seteuid");

1944

}

1945

goto end;

1946

}

1947

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

1948

network.ifr_flags |= IFF_UP;

1949

take_down_interface = true;

1950

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

1951

if(ret == -1){

1952

take_down_interface = false;

1953

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1954

exitcode = EX_OSERR;

1955

#ifdef __linux__

1956

if(restore_loglevel){

1957

ret = klogctl(7, NULL, 0);

1958

if(ret == -1){

1959

perror_plus("klogctl");

1960

}

1961

}

1962

#endif /* __linux__ */

1963

/* Lower privileges */

1964

errno = 0;

1965

ret = seteuid(uid);

1966

if(ret == -1){

1967

perror_plus("seteuid");

1968

}

1969

goto end;

1970

}

1971

}

1972

/* Sleep checking until interface is running.

1973

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

1974

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

1975

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

1976

if(ret == -1){

1977

perror_plus("ioctl SIOCGIFFLAGS");

1978

} else if(network.ifr_flags & IFF_RUNNING){

1979

break;

1980

}

1981

struct timespec sleeptime = { .tv_nsec = 250000000 };

1982

ret = nanosleep(&sleeptime, NULL);

1983

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

1984

perror_plus("nanosleep");

1985

}

1986

}

1987

if(not take_down_interface){

1988

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

1989

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

1990

if(ret == -1){

1991

perror_plus("close");

1992

}

1993

}

1994

#ifdef __linux__

1995

if(restore_loglevel){

1996

/* Restores kernel loglevel to default */

1997

ret = klogctl(7, NULL, 0);

1998

if(ret == -1){

1999

perror_plus("klogctl");

2000

}

2001

}

2002

#endif /* __linux__ */

2003

/* Lower privileges */

2004

errno = 0;

2005

if(take_down_interface){

2006

/* Lower privileges */

2007

ret = seteuid(uid);

2008

if(ret == -1){

2009

perror_plus("seteuid");

2010

}

2502

2011

} else {

2503

if(ret == 0){

2504

free(direntries);

2505

}

2506

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

2507

exitcode = EXIT_FAILURE;

2508

goto end;

2509

}

2510

}

2511

2512

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

2513

{

2514

char *interface = NULL;

2515

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

2516

interface))){

2517

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

2518

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

2519

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

2520

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

2521

interface);

2522

interface = NULL;

2523

while((interface = argz_next(mc.interfaces,

2524

mc.interfaces_size, interface))){

2525

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

2526

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

2527

interface);

2528

interface = NULL;

2529

}

2530

}

2531

break;

2532

}

2533

bool interface_was_up = interface_is_up(interface);

2534

errno = bring_up_interface(interface, delay);

2535

if(not interface_was_up){

2536

if(errno != 0){

2537

perror_plus("Failed to bring up interface");

2538

} else {

2539

errno = argz_add(&interfaces_to_take_down,

2540

&interfaces_to_take_down_size,

2541

interface);

2542

if(errno != 0){

2543

perror_plus("argz_add");

2544

}

2545

}

2546

}

2547

}

2548

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

2549

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

2550

}

2551

}

2552

2553

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

2554

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

2555

if(debug){

2556

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

2557

mc.interfaces);

2558

}

2559

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

2012

/* Lower privileges permanently */

2013

ret = setuid(uid);

2014

if(ret == -1){

2015

perror_plus("setuid");

2016

}

2017

}

2560

2018

}

2561

2019

2562

2020

if(quit_now){

2563

2021

goto end;

2564

2022

}

2565

2023

2566

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

2024

ret = init_gnutls_global(pubkey, seckey);

2567

2025

if(ret == -1){

2568

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

2026

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

2027

"init_gnutls_global failed\n");

2569

2028

exitcode = EX_UNAVAILABLE;

2570

2029

goto end;

2571

2030

} else {

2576

2035

goto end;

2577

2036

}

2578

2037

2579

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

2580

tempdir = mkdtemp(run_tempdir);

2581

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

2582

if(debug){

2583

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

2584

run_tempdir, old_tempdir);

2585

}

2586

tempdir = mkdtemp(old_tempdir);

2587

}

2588

if(tempdir == NULL){

2038

if(mkdtemp(tempdir) == NULL){

2589

2039

perror_plus("mkdtemp");

2590

2040

goto end;

2591

2041

}

2042

tempdir_created = true;

2592

2043

2593

2044

if(quit_now){

2594

2045

goto end;

2595

2046

}

2596

2047

2597

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

2598

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

2048

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

2049

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

2050

"init_gpgme failed\n");

2599

2051

exitcode = EX_UNAVAILABLE;

2600

2052

goto end;

2601

2053

} else {

2610

2062

/* Connect directly, do not use Zeroconf */

2611

2063

/* (Mainly meant for debugging) */

2612

2064

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

2613

2614

2065

if(address == NULL){

2615

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

2066

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

2067

"No colon in address\n");

2616

2068

exitcode = EX_USAGE;

2617

2069

goto end;

2618

2070

}

2621

2073

goto end;

2622

2074

}

2623

2075

2624

in_port_t port;

2076

uint16_t port;

2625

2077

errno = 0;

2626

2078

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

2627

2079

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

2628

or tmpmax != (in_port_t)tmpmax){

2629

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

2080

or tmpmax != (uint16_t)tmpmax){

2081

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

2082

"Bad port number\n");

2630

2083

exitcode = EX_USAGE;

2631

2084

goto end;

2632

2085

}

2633

2086

2634

2087

if(quit_now){

2635

2088

goto end;

2636

2089

}

2637

2090

2638

port = (in_port_t)tmpmax;

2091

port = (uint16_t)tmpmax;

2639

2092

*address = '\0';

2640

2093

/* Colon in address indicates IPv6 */

2641

2094

int af;

2657

2110

}

2658

2111

2659

2112

while(not quit_now){

2660

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

2661

&mc);

2113

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

2662

2114

if(quit_now or ret == 0){

2663

2115

break;

2664

2116

}

2665

2117

if(debug){

2666

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

2667

(int)retry_interval);

2118

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

2119

"Retrying in %d seconds\n", (int)retry_interval);

2668

2120

}

2669

sleep((unsigned int)retry_interval);

2121

sleep((int)retry_interval);

2670

2122

}

2671

2123

2672

if(not quit_now){

2124

if (not quit_now){

2673

2125

exitcode = EXIT_SUCCESS;

2674

2126

}

2675

2127

2690

2142

config.publish_domain = 0;

2691

2143

2692

2144

/* Allocate a new server */

2693

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2694

&config, NULL, NULL, &ret_errno);

2145

mc.server = avahi_server_new(avahi_simple_poll_get

2146

(mc.simple_poll), &config, NULL,

2147

NULL, &error);

2695

2148

2696

2149

/* Free the Avahi configuration data */

2697

2150

avahi_server_config_free(&config);

2699

2152

2700

2153

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

2701

2154

if(mc.server == NULL){

2702

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

2703

avahi_strerror(ret_errno));

2155

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

2156

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

2157

avahi_strerror(error));

2704

2158

exitcode = EX_UNAVAILABLE;

2705

2159

goto end;

2706

2160

}

2712

2166

/* Create the Avahi service browser */

2713

2167

sb = avahi_s_service_browser_new(mc.server, if_index,

2714

2168

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2715

NULL, 0, browse_callback,

2716

(void *)&mc);

2169

NULL, 0, browse_callback, NULL);

2717

2170

if(sb == NULL){

2718

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

2719

avahi_strerror(avahi_server_errno(mc.server)));

2171

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

2172

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

2173

avahi_strerror(avahi_server_errno(mc.server)));

2720

2174

exitcode = EX_UNAVAILABLE;

2721

2175

goto end;

2722

2176

}

2728

2182

/* Run the main loop */

2729

2183

2730

2184

if(debug){

2731

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

2185

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

2186

"Starting Avahi loop search\n");

2732

2187

}

2733

2734

ret = avahi_loop_with_timeout(simple_poll,

2735

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

2188

2189

ret = avahi_loop_with_timeout(mc.simple_poll,

2190

(int)(retry_interval * 1000));

2736

2191

if(debug){

2737

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

2738

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

2192

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

2193

"avahi_loop_with_timeout exited %s\n",

2194

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

2739

2195

}

2740

2196

2741

2197

end:

2742

2198

2743

2199

if(debug){

2744

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

2200

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

2201

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

2745

2202

}

2746

2203

2747

2204

/* Cleanup things */

2748

free(mc.interfaces);

2749

2750

2205

if(sb != NULL)

2751

2206

avahi_s_service_browser_free(sb);

2752

2207

2753

2208

if(mc.server != NULL)

2754

2209

avahi_server_free(mc.server);

2755

2210

2756

if(simple_poll != NULL)

2757

avahi_simple_poll_free(simple_poll);

2211

if(mc.simple_poll != NULL)

2212

avahi_simple_poll_free(mc.simple_poll);

2758

2213

2759

2214

if(gnutls_initialized){

2760

2215

gnutls_certificate_free_credentials(mc.cred);

2765

2220

if(gpgme_initialized){

2766

2221

gpgme_release(mc.ctx);

2767

2222

}

2768

2223

2769

2224

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

2770

2225

has seen */

2771

2226

if(mc.current_server != NULL){

2772

2227

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

2773

2228

while(mc.current_server != NULL){

2774

2229

server *next = mc.current_server->next;

2775

#ifdef __GNUC__

2776

#pragma GCC diagnostic push

2777

#pragma GCC diagnostic ignored "-Wcast-qual"

2778

#endif

2779

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

2780

#ifdef __GNUC__

2781

#pragma GCC diagnostic pop

2782

#endif

2783

2230

free(mc.current_server);

2784

2231

mc.current_server = next;

2785

2232

}

2786

2233

}

2787

2234

2788

/* Re-raise privileges */

2789

{

2790

ret_errno = raise_privileges();

2791

if(ret_errno != 0){

2792

errno = ret_errno;

2793

perror_plus("Failed to raise privileges");

2794

} else {

2795

2796

/* Run network hooks */

2797

run_network_hooks("stop", interfaces_hooks != NULL ?

2798

interfaces_hooks : "", delay);

2799

2800

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

2801

{

2802

char *interface = NULL;

2803

while((interface=argz_next(interfaces_to_take_down,

2804

interfaces_to_take_down_size,

2805

interface))){

2806

ret_errno = take_down_interface(interface);

2807

if(ret_errno != 0){

2808

errno = ret_errno;

2809

perror_plus("Failed to take down interface");

2810

}

2811

}

2812

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

2813

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

2814

" down\n");

2815

}

2816

}

2235

/* XXX run network hooks "stop" here */

2236

2237

/* Take down the network interface */

2238

if(take_down_interface){

2239

/* Re-raise priviliges */

2240

errno = 0;

2241

ret = seteuid(0);

2242

if(ret == -1){

2243

perror_plus("seteuid");

2817

2244

}

2818

2819

ret_errno = lower_privileges_permanently();

2820

if(ret_errno != 0){

2821

errno = ret_errno;

2822

perror_plus("Failed to lower privileges permanently");

2245

if(geteuid() == 0){

2246

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

2247

if(ret == -1){

2248

perror_plus("ioctl SIOCGIFFLAGS");

2249

} else if(network.ifr_flags & IFF_UP){

2250

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

2251

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

2252

if(ret == -1){

2253

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2254

}

2255

}

2256

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

2257

if(ret == -1){

2258

perror_plus("close");

2259

}

2260

/* Lower privileges permanently */

2261

errno = 0;

2262

ret = setuid(uid);

2263

if(ret == -1){

2264

perror_plus("setuid");

2265

}

2823

2266

}

2824

2267

}

2825

2268

2826

free(interfaces_to_take_down);

2827

free(interfaces_hooks);

2828

2829

2269

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

2830

if(tempdir != NULL){

2270

if(tempdir_created){

2831

2271

struct dirent **direntries = NULL;

2832

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

2833

| O_NOFOLLOW

2834

| O_DIRECTORY

2835

| O_PATH));

2836

if(tempdir_fd == -1){

2837

perror_plus("open");

2838

} else {

2839

#ifdef __GLIBC__

2840

#if __GLIBC_PREREQ(2, 15)

2841

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

2842

notdotentries, alphasort);

2843

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

2844

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

2845

alphasort);

2846

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

2847

#else /* not __GLIBC__ */

2848

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

2849

alphasort);

2850

#endif /* not __GLIBC__ */

2851

if(numentries >= 0){

2852

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

2853

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

2854

if(ret == -1){

2855

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

2856

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

2857

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

2858

}

2859

free(direntries[i]);

2860

}

2861

2862

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

2863

free(direntries);

2864

if(numentries == -1){

2865

perror_plus("scandir");

2866

}

2867

ret = rmdir(tempdir);

2868

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

2869

perror_plus("rmdir");

2870

}

2272

struct dirent *direntry = NULL;

2273

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

2274

alphasort);

2275

if (numentries > 0){

2276

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

2277

direntry = direntries[i];

2278

char *fullname = NULL;

2279

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

2280

direntry->d_name);

2281

if(ret < 0){

2282

perror_plus("asprintf");

2283

continue;

2284

}

2285

ret = remove(fullname);

2286

if(ret == -1){

2287

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

2288

"remove(\"%s\"): %s\n", fullname, strerror(errno));

2289

}

2290

free(fullname);

2871

2291

}

2872

TEMP_FAILURE_RETRY(close(tempdir_fd));

2292

}

2293

2294

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

2295

free(direntries);

2296

if (numentries == -1){

2297

perror_plus("scandir");

2298

}

2299

ret = rmdir(tempdir);

2300

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

2301

perror_plus("rmdir");

2873

2302

}

2874

2303

}

2875

2304