/*
in6_pcblookup_local_and_cleanup does everything
in6_pcblookup_local does but it checks for a socket
that's going away. Since we know that the lock is
held read+write when this function is called, we
can safely dispose of this socket like the slow
timer would usually do and return NULL. This is
great for bind.
*/
static struct inpcb*
in6_pcblookup_local_and_cleanup(
struct inpcbinfo *pcbinfo,
struct in6_addr *laddr,
u_int lport_arg,
int wild_okay)
{
struct inpcb *inp;
/* Perform normal lookup */
inp = in6_pcblookup_local(pcbinfo, laddr, lport_arg, wild_okay);
/* Check if we found a match but it's waiting to be disposed */
if (inp && inp->inp_wantcnt == WNT_STOPUSING) {
struct socket *so = inp->inp_socket;
lck_mtx_lock(inp->inpcb_mtx);
if (so->so_usecount == 0) {
in_pcbdispose(inp);
inp = NULL;
}
else {
lck_mtx_unlock(inp->inpcb_mtx);
}
}
return inp;
}
/*
* XXX: this is borrowed from in6_pcbbind(). If possible, we should
* share this function by all *bsd*...
*/
int
in6_pcbsetport(
__unused struct in6_addr *laddr,
struct inpcb *inp,
struct proc *p,
int locked)
{
struct socket *so = inp->inp_socket;
u_int16_t lport = 0, first, last, *lastport;
int count, error = 0, wild = 0;
struct inpcbinfo *pcbinfo = inp->inp_pcbinfo;
kauth_cred_t cred;
if (!locked) { /* Make sure we don't run into a deadlock: 4052373 */
if (!lck_rw_try_lock_exclusive(pcbinfo->mtx)) {
socket_unlock(inp->inp_socket, 0);
lck_rw_lock_exclusive(pcbinfo->mtx);
socket_lock(inp->inp_socket, 0);
}
}
/* XXX: this is redundant when called from in6_pcbbind */
if ((so->so_options & (SO_REUSEADDR|SO_REUSEPORT)) == 0)
wild = INPLOOKUP_WILDCARD;
inp->inp_flags |= INP_ANONPORT;
if (inp->inp_flags & INP_HIGHPORT) {
first = ipport_hifirstauto; /* sysctl */
last = ipport_hilastauto;
lastport = &pcbinfo->lasthi;
} else if (inp->inp_flags & INP_LOWPORT) {
cred = kauth_cred_proc_ref(p);
error = priv_check_cred(cred, PRIV_NETINET_RESERVEDPORT, 0);
kauth_cred_unref(&cred);
if (error != 0) {
if (!locked)
lck_rw_done(pcbinfo->mtx);
return error;
}
first = ipport_lowfirstauto; /* 1023 */
last = ipport_lowlastauto; /* 600 */
lastport = &pcbinfo->lastlow;
} else {
first = ipport_firstauto; /* sysctl */
last = ipport_lastauto;
lastport = &pcbinfo->lastport;
}
/*
* Simple check to ensure all ports are not used up causing
* a deadlock here.
*
* We split the two cases (up and down) so that the direction
* is not being tested on each round of the loop.
*/
if (first > last) {
/*
* counting down
*/
count = first - last;
do {
if (count-- < 0) { /* completely used? */
/*
* Undo any address bind that may have
* occurred above.
*/
inp->in6p_laddr = in6addr_any;
inp->in6p_last_outif = 0;
if (!locked)
lck_rw_done(pcbinfo->mtx);
return (EAGAIN);
}
--*lastport;
if (*lastport > first || *lastport < last)
*lastport = first;
lport = htons(*lastport);
} while (in6_pcblookup_local(pcbinfo,
&inp->in6p_laddr, lport, wild));
} else {
/*
* counting up
*/
count = last - first;
do {
if (count-- < 0) { /* completely used? */
/*
* Undo any address bind that may have
* occurred above.
*/
inp->in6p_laddr = in6addr_any;
inp->in6p_last_outif = 0;
if (!locked)
lck_rw_done(pcbinfo->mtx);
return (EAGAIN);
}
++*lastport;
if (*lastport < first || *lastport > last)
*lastport = first;
lport = htons(*lastport);
} while (in6_pcblookup_local(pcbinfo,
&inp->in6p_laddr, lport, wild));
}
inp->inp_lport = lport;
if (in_pcbinshash(inp, 1) != 0) {
inp->in6p_laddr = in6addr_any;
inp->inp_lport = 0;
inp->in6p_last_outif = 0;
if (!locked)
lck_rw_done(pcbinfo->mtx);
return (EAGAIN);
}
if (!locked)
lck_rw_done(pcbinfo->mtx);
return(0);
}