static int
doUtdbrlonly (xmlNode * node, int action)
{
xmlNode *child;
if (node == NULL)
return 0;
if (ud->top == 0)
action = 1;
if (action != 0)
push_sem_stack (node);
switch (ud->stack[ud->top])
{
case utdnewpage:
doUtdnewpage (node);
if (action != 0)
pop_sem_stack ();
return 1;
case utdnewline:
doUtdnewline (node);
if (action != 0)
pop_sem_stack ();
return 1;
case utddispimg:
transcribe_graphic (node, 0);
if (action != 0)
pop_sem_stack ();
return 1;
case changetable:
change_table (node);
return 1;
default:
break;
}
child = node->children;
while (child)
{
switch (child->type)
{
case XML_ELEMENT_NODE:
doUtdbrlonly (child, 1);
break;
case XML_TEXT_NODE:
doDotsText (child);
break;
default:
break;
}
child = child->next;
}
if (action != 0)
pop_sem_stack ();
return 1;
}
/*
* function that removes our stuff when we go away.
*/
static __dead void
do_death(int active)
{
int ret = 0;
if (active) {
change_filter(0, luser, ipsrc);
change_table(0, ipsrc);
authpf_kill_states();
remove_stale_rulesets();
}
if (pidfile[0] && (pidfp != NULL))
if (unlink(pidfile) == -1)
syslog(LOG_ERR, "cannot unlink %s (%m)", pidfile);
exit(ret);
}
/*
* function that removes our stuff when we go away.
*/
static __dead void
do_death(int active)
{
int ret = 0;
if (active) {
change_filter(0, luser, ipsrc);
if (user_ip) {
change_table(0, ipsrc);
authpf_kill_states();
}
}
if (pidfile[0] && pidfd != -1)
if (unlink(pidfile) == -1)
syslog(LOG_ERR, "cannot unlink %s (%m)", pidfile);
exit(ret);
}
/*
* User shell for authenticating gateways. Sole purpose is to allow
* a user to ssh to a gateway, and have the gateway modify packet
* filters to allow access, then remove access when the user finishes
* up. Meant to be used only from ssh(1) connections.
*/
int
main(void)
{
int lockcnt = 0, n;
FILE *config;
struct in6_addr ina;
struct passwd *pw;
char *cp;
gid_t gid;
uid_t uid;
const char *shell;
login_cap_t *lc;
if (strcmp(__progname, "-authpf-noip") == 0)
user_ip = 0;
config = fopen(PATH_CONFFILE, "r");
if (config == NULL) {
syslog(LOG_ERR, "cannot open %s (%m)", PATH_CONFFILE);
exit(1);
}
if ((cp = getenv("SSH_TTY")) == NULL) {
syslog(LOG_ERR, "non-interactive session connection for authpf");
exit(1);
}
if ((cp = getenv("SSH_CLIENT")) == NULL) {
syslog(LOG_ERR, "cannot determine connection source");
exit(1);
}
if (strlcpy(ipsrc, cp, sizeof(ipsrc)) >= sizeof(ipsrc)) {
syslog(LOG_ERR, "SSH_CLIENT variable too long");
exit(1);
}
cp = strchr(ipsrc, ' ');
if (!cp) {
syslog(LOG_ERR, "corrupt SSH_CLIENT variable %s", ipsrc);
exit(1);
}
*cp = '\0';
if (inet_pton(AF_INET, ipsrc, &ina) != 1 &&
inet_pton(AF_INET6, ipsrc, &ina) != 1) {
syslog(LOG_ERR,
"cannot determine IP from SSH_CLIENT %s", ipsrc);
exit(1);
}
/* open the pf device */
dev = open(PATH_DEVFILE, O_RDWR);
if (dev == -1) {
syslog(LOG_ERR, "cannot open packet filter device (%m)");
goto die;
}
uid = getuid();
pw = getpwuid(uid);
if (pw == NULL) {
syslog(LOG_ERR, "cannot find user for uid %u", uid);
goto die;
}
if ((lc = login_getclass(pw->pw_class)) != NULL)
shell = login_getcapstr(lc, "shell", pw->pw_shell,
pw->pw_shell);
else
shell = pw->pw_shell;
#ifndef __FreeBSD__
login_close(lc);
#endif
if (strcmp(shell, PATH_AUTHPF_SHELL) &&
strcmp(shell, PATH_AUTHPF_SHELL_NOIP)) {
syslog(LOG_ERR, "wrong shell for user %s, uid %u",
pw->pw_name, pw->pw_uid);
#ifdef __FreeBSD__
login_close(lc);
#else
if (shell != pw->pw_shell)
free(shell);
#endif
goto die;
}
#ifdef __FreeBSD__
login_close(lc);
#else
if (shell != pw->pw_shell)
free(shell);
#endif
/*
* Paranoia, but this data _does_ come from outside authpf, and
* truncation would be bad.
*/
if (strlcpy(luser, pw->pw_name, sizeof(luser)) >= sizeof(luser)) {
syslog(LOG_ERR, "username too long: %s", pw->pw_name);
goto die;
}
if ((n = snprintf(rulesetname, sizeof(rulesetname), "%s(%ld)",
luser, (long)getpid())) < 0 || (u_int)n >= sizeof(rulesetname)) {
syslog(LOG_INFO, "%s(%ld) too large, ruleset name will be %ld",
luser, (long)getpid(), (long)getpid());
if ((n = snprintf(rulesetname, sizeof(rulesetname), "%ld",
(long)getpid())) < 0 || (u_int)n >= sizeof(rulesetname)) {
syslog(LOG_ERR, "pid too large for ruleset name");
goto die;
}
}
/* Make our entry in /var/authpf as ipaddr or username */
n = snprintf(pidfile, sizeof(pidfile), "%s/%s",
PATH_PIDFILE, user_ip ? ipsrc : luser);
if (n < 0 || (u_int)n >= sizeof(pidfile)) {
syslog(LOG_ERR, "path to pidfile too long");
goto die;
}
signal(SIGTERM, need_death);
signal(SIGINT, need_death);
signal(SIGALRM, need_death);
signal(SIGPIPE, need_death);
signal(SIGHUP, need_death);
signal(SIGQUIT, need_death);
signal(SIGTSTP, need_death);
/*
* If someone else is already using this ip, then this person
* wants to switch users - so kill the old process and exit
* as well.
*
* Note, we could print a message and tell them to log out, but the
* usual case of this is that someone has left themselves logged in,
* with the authenticated connection iconized and someone else walks
* up to use and automatically logs in before using. If this just
* gets rid of the old one silently, the new user never knows they
* could have used someone else's old authentication. If we
* tell them to log out before switching users it is an invitation
* for abuse.
*/
do {
int save_errno, otherpid = -1;
char otherluser[MAXLOGNAME];
if ((pidfd = open(pidfile, O_RDWR|O_CREAT, 0644)) == -1 ||
(pidfp = fdopen(pidfd, "r+")) == NULL) {
if (pidfd != -1)
close(pidfd);
syslog(LOG_ERR, "cannot open or create %s: %s", pidfile,
strerror(errno));
goto die;
}
if (flock(fileno(pidfp), LOCK_EX|LOCK_NB) == 0)
break;
save_errno = errno;
/* Mark our pid, and username to our file. */
rewind(pidfp);
/* 31 == MAXLOGNAME - 1 */
if (fscanf(pidfp, "%d\n%31s\n", &otherpid, otherluser) != 2)
otherpid = -1;
syslog(LOG_DEBUG, "tried to lock %s, in use by pid %d: %s",
pidfile, otherpid, strerror(save_errno));
if (otherpid > 0) {
syslog(LOG_INFO,
"killing prior auth (pid %d) of %s by user %s",
otherpid, ipsrc, otherluser);
if (kill((pid_t) otherpid, SIGTERM) == -1) {
syslog(LOG_INFO,
"could not kill process %d: (%m)",
otherpid);
}
}
/*
* We try to kill the previous process and acquire the lock
* for 10 seconds, trying once a second. if we can't after
* 10 attempts we log an error and give up.
*/
if (want_death || ++lockcnt > 10) {
if (!want_death)
syslog(LOG_ERR, "cannot kill previous authpf (pid %d)",
otherpid);
fclose(pidfp);
pidfp = NULL;
pidfd = -1;
goto dogdeath;
}
sleep(1);
/* re-open, and try again. The previous authpf process
* we killed above should unlink the file and release
* it's lock, giving us a chance to get it now
*/
fclose(pidfp);
pidfp = NULL;
pidfd = -1;
} while (1);
/* whack the group list */
gid = getegid();
if (setgroups(1, &gid) == -1) {
syslog(LOG_INFO, "setgroups: %s", strerror(errno));
do_death(0);
}
/* revoke privs */
uid = getuid();
if (setresuid(uid, uid, uid) == -1) {
syslog(LOG_INFO, "setresuid: %s", strerror(errno));
do_death(0);
}
openlog("authpf", LOG_PID | LOG_NDELAY, LOG_DAEMON);
if (!check_luser(PATH_BAN_DIR, luser) || !allowed_luser(pw)) {
syslog(LOG_INFO, "user %s prohibited", luser);
do_death(0);
}
if (read_config(config)) {
syslog(LOG_ERR, "invalid config file %s", PATH_CONFFILE);
do_death(0);
}
if (remove_stale_rulesets()) {
syslog(LOG_INFO, "error removing stale rulesets");
do_death(0);
}
/* We appear to be making headway, so actually mark our pid */
rewind(pidfp);
fprintf(pidfp, "%ld\n%s\n", (long)getpid(), luser);
fflush(pidfp);
(void) ftruncate(fileno(pidfp), ftello(pidfp));
if (change_filter(1, luser, ipsrc) == -1) {
printf("Unable to modify filters\r\n");
do_death(0);
}
if (user_ip && change_table(1, ipsrc) == -1) {
printf("Unable to modify table\r\n");
change_filter(0, luser, ipsrc);
do_death(0);
}
while (1) {
printf("\r\nHello %s. ", luser);
printf("You are authenticated from host \"%s\"\r\n", ipsrc);
setproctitle("%s@%s", luser, ipsrc);
print_message(PATH_MESSAGE);
while (1) {
sleep(10);
if (want_death)
do_death(1);
}
}
/* NOTREACHED */
dogdeath:
printf("\r\n\r\nSorry, this service is currently unavailable due to ");
printf("technical difficulties\r\n\r\n");
print_message(PATH_PROBLEM);
printf("\r\nYour authentication process (pid %ld) was unable to run\n",
(long)getpid());
sleep(180); /* them lusers read reaaaaal slow */
die:
do_death(0);
}
int
volumesDoBrlNode (xmlNode * node, int action)
{
xmlNode *child;
if (node == NULL)
return 0;
if (action == 0)
ud->outbuf1_len_so_far = 0;
else
push_sem_stack (node);
switch (ud->stack[ud->top])
{
case markhead:
if (ud->head_node == NULL)
ud->head_node = node;
pop_sem_stack ();
break;
case utdbrlonly:
doUtdbrlonly (node, 0);
if (action != 0)
pop_sem_stack ();
return 1;
case utdnewpage:
doUtdnewpage (node);
if (action != 0)
pop_sem_stack ();
return 1;
case utdnewline:
doUtdnewline (node);
if (action != 0)
pop_sem_stack ();
return 1;
case utddispimg:
transcribe_graphic (node, 0);
if (action != 0)
pop_sem_stack ();
return 1;
case changetable:
change_table (node);
return 1;
default:
break;
}
child = node->children;
while (child)
{
switch (child->type)
{
case XML_ELEMENT_NODE:
volumesDoBrlNode (child, 1);
break;
case XML_TEXT_NODE:
doDotsText (child);
break;
default:
break;
}
child = child->next;
}
if (action != 0)
{
pop_sem_stack ();
return 1;
}
finishBrlNode ();
return 1;
}
