/* Check for the validity of a jail in the given path, mounting it if it looks
* empty.
* TODO: Updating /etc/mtab would be nice. */
void mount_if_needed(const char *jail_src_base, const char *jail_base,
const char *jail_system, const char *jailpath)
{
char *jailsrc;
char *jaillib;
char *source_bits;
char *target_bits;
/* Check if there is something useful in the jail. If not, it's probably
* not mounted. */
jaillib = die_if_null(malloc(strlen(jailpath) + 5));
sprintf(jaillib, "%s/lib", jailpath);
if (access(jaillib, F_OK))
{
/* No /lib? Mustn't be mounted. Mount it, creating the dir if needed. */
if (access(jailpath, F_OK))
{
if(mkdir(jailpath, 0755))
{
syslog(LOG_ERR, "could not create mountpoint %s\n", jailpath);
perror("could not create jail mountpoint");
exit(1);
}
syslog(LOG_NOTICE, "created mountpoint %s\n", jailpath);
}
jailsrc = jail_src(jail_src_base, jail_base, jailpath);
checked_mount(jail_system, jailpath, NULL, MS_BIND | MS_RDONLY, NULL);
source_bits = die_if_null(malloc(strlen(jailsrc) + 5 + 1));
target_bits = die_if_null(malloc(strlen(jailpath) + 5 + 1));
sprintf(source_bits, "%s/home", jailsrc);
sprintf(target_bits, "%s/home", jailpath);
checked_mount(source_bits, target_bits, NULL, MS_BIND, NULL);
sprintf(source_bits, "%s/tmp", jailsrc);
sprintf(target_bits, "%s/tmp", jailpath);
checked_mount(source_bits, target_bits, NULL, MS_BIND, NULL);
syslog(LOG_INFO, "mounted %s\n", jailpath);
free(jailsrc);
free(source_bits);
free(target_bits);
}
free(jaillib);
}
void *
xrealloc (void *p, size_t size) {
void *t;
t = realloc(p, size);
die_if_null(t);
return t;
}
/* Unsets any signal mask applied by the parent process */
int unmask_signals(void)
{
int result;
sigset_t* sigset;
sigset = die_if_null(malloc(sizeof(sigset_t)));
sigemptyset(sigset);
result = sigprocmask(SIG_SETMASK, sigset, NULL);
free(sigset);
printf("%d", result);
return result;
}
char *
xstrdup (const char *s) {
char *t;
if (s == NULL)
return NULL;
t = strdup(s);
die_if_null(t);
return t;
}
void *
xmalloc (size_t size) {
void *t;
if (size == 0)
return NULL;
t = malloc(size);
die_if_null(t);
return t;
}
/* Find the path of the user components of a jail, given a mountpoint. */
char *jail_src(const char *jail_src_base, const char *jail_base,
const char *jailpath)
{
char* src;
int srclen;
int dstlen;
srclen = strlen(jail_src_base);
dstlen = strlen(jail_base);
src = die_if_null(malloc(strlen(jailpath) + (srclen - dstlen) + 1));
strcpy(src, jail_src_base);
strcat(src, jailpath+dstlen);
return src;
}
