/*
* Called by KCF_PROV_REFRELE when a provider's reference count drops
* to zero. We free the descriptor when the last reference is released.
* However, for software providers, we do not free it when there is an
* unregister thread waiting. We signal that thread in this case and
* that thread is responsible for freeing the descriptor.
*/
void
kcf_provider_zero_refcnt(kcf_provider_desc_t *desc)
{
mutex_enter(&desc->pd_lock);
switch (desc->pd_prov_type) {
case CRYPTO_SW_PROVIDER:
if (desc->pd_state == KCF_PROV_REMOVED ||
desc->pd_state == KCF_PROV_DISABLED) {
desc->pd_state = KCF_PROV_FREED;
cv_broadcast(&desc->pd_remove_cv);
mutex_exit(&desc->pd_lock);
break;
}
/* FALLTHRU */
case CRYPTO_HW_PROVIDER:
case CRYPTO_LOGICAL_PROVIDER:
mutex_exit(&desc->pd_lock);
kcf_free_provider_desc(desc);
}
}
/* Caller must hold prov_tab_mutex */
static void
kcf_free_unregistered_provs()
{
int i;
kcf_provider_desc_t *pd;
boolean_t walk_again = B_FALSE;
ASSERT(MUTEX_HELD(&prov_tab_mutex));
for (i = 0; i < KCF_MAX_PROVIDERS; i++) {
if ((pd = prov_tab[i]) == NULL ||
pd->pd_prov_type == CRYPTO_SW_PROVIDER ||
pd->pd_state != KCF_PROV_UNREGISTERED)
continue;
if (kcf_get_refcnt(pd, B_TRUE) == 0) {
/* kcf_free_provider_desc drops prov_tab_mutex */
kcf_free_provider_desc(pd);
mutex_enter(&prov_tab_mutex);
} else
walk_again = B_TRUE;
}
kcf_need_provtab_walk = walk_again;
}
/*
* This routine is used to notify the framework when a provider is being
* removed. Hardware providers call this routine in their detach routines.
* Software providers call this routine in their _fini() routine.
*/
int
crypto_unregister_provider(crypto_kcf_provider_handle_t handle)
{
uint_t mech_idx;
kcf_provider_desc_t *desc;
kcf_prov_state_t saved_state;
/* lookup provider descriptor */
if ((desc = kcf_prov_tab_lookup((crypto_provider_id_t)handle)) == NULL)
return (CRYPTO_UNKNOWN_PROVIDER);
mutex_enter(&desc->pd_lock);
/*
* Check if any other thread is disabling or removing
* this provider. We return if this is the case.
*/
if (desc->pd_state >= KCF_PROV_DISABLED) {
mutex_exit(&desc->pd_lock);
/* Release reference held by kcf_prov_tab_lookup(). */
KCF_PROV_REFRELE(desc);
return (CRYPTO_BUSY);
}
saved_state = desc->pd_state;
desc->pd_state = KCF_PROV_REMOVED;
if (saved_state == KCF_PROV_BUSY) {
/*
* The per-provider taskq threads may be waiting. We
* signal them so that they can start failing requests.
*/
cv_broadcast(&desc->pd_resume_cv);
}
if (desc->pd_prov_type == CRYPTO_SW_PROVIDER) {
/*
* Check if this provider is currently being used.
* pd_irefcnt is the number of holds from the internal
* structures. We add one to account for the above lookup.
*/
if (desc->pd_refcnt > desc->pd_irefcnt + 1) {
desc->pd_state = saved_state;
mutex_exit(&desc->pd_lock);
/* Release reference held by kcf_prov_tab_lookup(). */
KCF_PROV_REFRELE(desc);
/*
* The administrator presumably will stop the clients
* thus removing the holds, when they get the busy
* return value. Any retry will succeed then.
*/
return (CRYPTO_BUSY);
}
}
mutex_exit(&desc->pd_lock);
if (desc->pd_prov_type != CRYPTO_SW_PROVIDER) {
remove_provider(desc);
}
if (desc->pd_prov_type != CRYPTO_LOGICAL_PROVIDER) {
/* remove the provider from the mechanisms tables */
for (mech_idx = 0; mech_idx < desc->pd_mech_list_count;
mech_idx++) {
kcf_remove_mech_provider(
desc->pd_mechanisms[mech_idx].cm_mech_name, desc);
}
}
/* remove provider from providers table */
if (kcf_prov_tab_rem_provider((crypto_provider_id_t)handle) !=
CRYPTO_SUCCESS) {
/* Release reference held by kcf_prov_tab_lookup(). */
KCF_PROV_REFRELE(desc);
return (CRYPTO_UNKNOWN_PROVIDER);
}
delete_kstat(desc);
if (desc->pd_prov_type == CRYPTO_SW_PROVIDER) {
/* Release reference held by kcf_prov_tab_lookup(). */
KCF_PROV_REFRELE(desc);
/*
* Wait till the existing requests complete.
*/
mutex_enter(&desc->pd_lock);
while (desc->pd_state != KCF_PROV_FREED)
cv_wait(&desc->pd_remove_cv, &desc->pd_lock);
mutex_exit(&desc->pd_lock);
} else {
/*
* Wait until requests that have been sent to the provider
* complete.
*/
mutex_enter(&desc->pd_lock);
while (desc->pd_irefcnt > 0)
cv_wait(&desc->pd_remove_cv, &desc->pd_lock);
mutex_exit(&desc->pd_lock);
}
kcf_do_notify(desc, B_FALSE);
if (desc->pd_prov_type == CRYPTO_SW_PROVIDER) {
/*
* This is the only place where kcf_free_provider_desc()
* is called directly. KCF_PROV_REFRELE() should free the
* structure in all other places.
*/
ASSERT(desc->pd_state == KCF_PROV_FREED &&
desc->pd_refcnt == 0);
kcf_free_provider_desc(desc);
} else {
KCF_PROV_REFRELE(desc);
}
return (CRYPTO_SUCCESS);
}
