mirror_zfs/module/icp/spi/kcf_spi.c

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/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2008 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/*
* This file is part of the core Kernel Cryptographic Framework.
* It implements the SPI functions exported to cryptographic
* providers.
*/
#include <sys/zfs_context.h>
#include <sys/crypto/common.h>
#include <sys/crypto/impl.h>
#include <sys/crypto/sched_impl.h>
#include <sys/crypto/spi.h>
static int init_prov_mechs(const crypto_provider_info_t *,
kcf_provider_desc_t *);
static int kcf_prov_kstat_update(kstat_t *, int);
static void delete_kstat(kcf_provider_desc_t *);
static const kcf_prov_stats_t kcf_stats_ks_data_template = {
{ "kcf_ops_total", KSTAT_DATA_UINT64 },
{ "kcf_ops_passed", KSTAT_DATA_UINT64 },
{ "kcf_ops_failed", KSTAT_DATA_UINT64 },
{ "kcf_ops_returned_busy", KSTAT_DATA_UINT64 }
};
/*
* This routine is used to add cryptographic providers to the KEF framework.
* Providers pass a crypto_provider_info structure to crypto_register_provider()
* and get back a handle. The crypto_provider_info structure contains a
* list of mechanisms supported by the provider and an ops vector containing
* provider entry points. Providers call this routine in their _init() routine.
*/
int
crypto_register_provider(const crypto_provider_info_t *info,
crypto_kcf_provider_handle_t *handle)
{
kcf_provider_desc_t *prov_desc = NULL;
int ret = CRYPTO_ARGUMENTS_BAD;
/*
* Allocate and initialize a new provider descriptor. We also
* hold it and release it when done.
*/
prov_desc = kcf_alloc_provider_desc();
KCF_PROV_REFHOLD(prov_desc);
/* copy provider description string */
prov_desc->pd_description = info->pi_provider_description;
/* Change from Illumos: the ops vector is persistent. */
prov_desc->pd_ops_vector = info->pi_ops_vector;
/* process the mechanisms supported by the provider */
if ((ret = init_prov_mechs(info, prov_desc)) != CRYPTO_SUCCESS)
goto bail;
/*
* Add provider to providers tables, also sets the descriptor
* pd_prov_id field.
*/
if ((ret = kcf_prov_tab_add_provider(prov_desc)) != CRYPTO_SUCCESS) {
undo_register_provider(prov_desc, B_FALSE);
goto bail;
}
/*
* The global queue is used for providers. We handle ordering
* of multi-part requests in the taskq routine. So, it is safe to
* have multiple threads for the taskq. We pass TASKQ_PREPOPULATE flag
* to keep some entries cached to improve performance.
*/
/*
* Create the kstat for this provider. There is a kstat
* installed for each successfully registered provider.
* This kstat is deleted, when the provider unregisters.
*/
prov_desc->pd_kstat = kstat_create("kcf", 0, "NONAME_provider_stats",
"crypto", KSTAT_TYPE_NAMED, sizeof (kcf_prov_stats_t) /
sizeof (kstat_named_t), KSTAT_FLAG_VIRTUAL);
if (prov_desc->pd_kstat != NULL) {
bcopy(&kcf_stats_ks_data_template,
&prov_desc->pd_ks_data,
sizeof (kcf_stats_ks_data_template));
prov_desc->pd_kstat->ks_data = &prov_desc->pd_ks_data;
KCF_PROV_REFHOLD(prov_desc);
KCF_PROV_IREFHOLD(prov_desc);
prov_desc->pd_kstat->ks_private = prov_desc;
prov_desc->pd_kstat->ks_update = kcf_prov_kstat_update;
kstat_install(prov_desc->pd_kstat);
}
mutex_enter(&prov_desc->pd_lock);
prov_desc->pd_state = KCF_PROV_READY;
mutex_exit(&prov_desc->pd_lock);
*handle = prov_desc->pd_kcf_prov_handle;
ret = CRYPTO_SUCCESS;
bail:
KCF_PROV_REFRELE(prov_desc);
return (ret);
}
/*
* This routine is used to notify the framework when a provider is being
* removed. 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;
/*
* 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 will presumably 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);
/* 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);
/* 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);
/*
* 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);
return (CRYPTO_SUCCESS);
}
/*
* Process the mechanism info structures specified by the provider
* during registration. A NULL crypto_provider_info_t indicates
* an already initialized provider descriptor.
*
* Returns CRYPTO_SUCCESS on success, CRYPTO_ARGUMENTS if one
* of the specified mechanisms was malformed, or CRYPTO_HOST_MEMORY
* if the table of mechanisms is full.
*/
static int
init_prov_mechs(const crypto_provider_info_t *info, kcf_provider_desc_t *desc)
{
uint_t mech_idx;
uint_t cleanup_idx;
int err = CRYPTO_SUCCESS;
kcf_prov_mech_desc_t *pmd;
int desc_use_count = 0;
/*
* Copy the mechanism list from the provider info to the provider
* descriptor. desc->pd_mechanisms has an extra crypto_mech_info_t
* element if the provider has random_ops since we keep an internal
* mechanism, SUN_RANDOM, in this case.
*/
if (info != NULL) {
ASSERT(info->pi_mechanisms != NULL);
desc->pd_mech_list_count = info->pi_mech_list_count;
desc->pd_mechanisms = info->pi_mechanisms;
}
/*
* For each mechanism support by the provider, add the provider
* to the corresponding KCF mechanism mech_entry chain.
*/
for (mech_idx = 0; mech_idx < desc->pd_mech_list_count; mech_idx++) {
const crypto_mech_info_t *mi = &desc->pd_mechanisms[mech_idx];
if ((mi->cm_mech_flags & CRYPTO_KEYSIZE_UNIT_IN_BITS) &&
(mi->cm_mech_flags & CRYPTO_KEYSIZE_UNIT_IN_BYTES)) {
err = CRYPTO_ARGUMENTS_BAD;
break;
}
if ((err = kcf_add_mech_provider(mech_idx, desc, &pmd)) !=
KCF_SUCCESS)
break;
if (pmd == NULL)
continue;
/* The provider will be used for this mechanism */
desc_use_count++;
}
/*
* Don't allow multiple providers with disabled mechanisms
* to register. Subsequent enabling of mechanisms will result in
* an unsupported configuration, i.e. multiple providers
* per mechanism.
*/
if (desc_use_count == 0)
return (CRYPTO_ARGUMENTS_BAD);
if (err == KCF_SUCCESS)
return (CRYPTO_SUCCESS);
/*
* An error occurred while adding the mechanism, cleanup
* and bail.
*/
for (cleanup_idx = 0; cleanup_idx < mech_idx; cleanup_idx++) {
kcf_remove_mech_provider(
desc->pd_mechanisms[cleanup_idx].cm_mech_name, desc);
}
if (err == KCF_MECH_TAB_FULL)
return (CRYPTO_HOST_MEMORY);
return (CRYPTO_ARGUMENTS_BAD);
}
/*
* Update routine for kstat. Only privileged users are allowed to
* access this information, since this information is sensitive.
* There are some cryptographic attacks (e.g. traffic analysis)
* which can use this information.
*/
static int
kcf_prov_kstat_update(kstat_t *ksp, int rw)
{
kcf_prov_stats_t *ks_data;
kcf_provider_desc_t *pd = (kcf_provider_desc_t *)ksp->ks_private;
if (rw == KSTAT_WRITE)
return (EACCES);
ks_data = ksp->ks_data;
ks_data->ps_ops_total.value.ui64 = pd->pd_sched_info.ks_ndispatches;
ks_data->ps_ops_failed.value.ui64 = pd->pd_sched_info.ks_nfails;
ks_data->ps_ops_busy_rval.value.ui64 = pd->pd_sched_info.ks_nbusy_rval;
ks_data->ps_ops_passed.value.ui64 =
pd->pd_sched_info.ks_ndispatches -
pd->pd_sched_info.ks_nfails -
pd->pd_sched_info.ks_nbusy_rval;
return (0);
}
/*
* Utility routine called from failure paths in crypto_register_provider()
* and from crypto_load_soft_disabled().
*/
void
undo_register_provider(kcf_provider_desc_t *desc, boolean_t remove_prov)
{
uint_t mech_idx;
/* 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 (remove_prov)
(void) kcf_prov_tab_rem_provider(desc->pd_prov_id);
}
static void
delete_kstat(kcf_provider_desc_t *desc)
{
/* destroy the kstat created for this provider */
if (desc->pd_kstat != NULL) {
kcf_provider_desc_t *kspd = desc->pd_kstat->ks_private;
/* release reference held by desc->pd_kstat->ks_private */
ASSERT(desc == kspd);
kstat_delete(kspd->pd_kstat);
desc->pd_kstat = NULL;
KCF_PROV_REFRELE(kspd);
KCF_PROV_IREFRELE(kspd);
}
}