1 // SPDX-License-Identifier: CDDL-1.0
2 /*
3 * CDDL HEADER START
4 *
5 * The contents of this file are subject to the terms of the
6 * Common Development and Distribution License (the "License").
7 * You may not use this file except in compliance with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or https://opensource.org/licenses/CDDL-1.0.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22 /*
23 * Copyright 2008 Sun Microsystems, Inc. All rights reserved.
24 * Use is subject to license terms.
25 */
26
27 /*
28 * This file contains the core framework routines for the
29 * kernel cryptographic framework. These routines are at the
30 * layer, between the kernel API/ioctls and the SPI.
31 */
32
33 #include <sys/zfs_context.h>
34 #include <sys/crypto/common.h>
35 #include <sys/crypto/impl.h>
36 #include <sys/crypto/sched_impl.h>
37 #include <sys/crypto/api.h>
38
39 /* kmem caches used by the scheduler */
40 static kmem_cache_t *kcf_context_cache;
41
42 /*
43 * Create a new context.
44 */
45 crypto_ctx_t *
kcf_new_ctx(kcf_provider_desc_t * pd)46 kcf_new_ctx(kcf_provider_desc_t *pd)
47 {
48 crypto_ctx_t *ctx;
49 kcf_context_t *kcf_ctx;
50
51 kcf_ctx = kmem_cache_alloc(kcf_context_cache, KM_SLEEP);
52 if (kcf_ctx == NULL)
53 return (NULL);
54
55 /* initialize the context for the consumer */
56 kcf_ctx->kc_refcnt = 1;
57 KCF_PROV_REFHOLD(pd);
58 kcf_ctx->kc_prov_desc = pd;
59 kcf_ctx->kc_sw_prov_desc = NULL;
60
61 ctx = &kcf_ctx->kc_glbl_ctx;
62 ctx->cc_provider_private = NULL;
63 ctx->cc_framework_private = (void *)kcf_ctx;
64
65 return (ctx);
66 }
67
68 /*
69 * We're done with this framework context, so free it. Note that freeing
70 * framework context (kcf_context) frees the global context (crypto_ctx).
71 *
72 * The provider is responsible for freeing provider private context after a
73 * final or single operation and resetting the cc_provider_private field
74 * to NULL. It should do this before it notifies the framework of the
75 * completion. We still need to call KCF_PROV_FREE_CONTEXT to handle cases
76 * like crypto_cancel_ctx(9f).
77 */
78 void
kcf_free_context(kcf_context_t * kcf_ctx)79 kcf_free_context(kcf_context_t *kcf_ctx)
80 {
81 kcf_provider_desc_t *pd = kcf_ctx->kc_prov_desc;
82 crypto_ctx_t *gctx = &kcf_ctx->kc_glbl_ctx;
83
84 if (gctx->cc_provider_private != NULL) {
85 mutex_enter(&pd->pd_lock);
86 if (!KCF_IS_PROV_REMOVED(pd)) {
87 /*
88 * Increment the provider's internal refcnt so it
89 * doesn't unregister from the framework while
90 * we're calling the entry point.
91 */
92 KCF_PROV_IREFHOLD(pd);
93 mutex_exit(&pd->pd_lock);
94 (void) KCF_PROV_FREE_CONTEXT(pd, gctx);
95 KCF_PROV_IREFRELE(pd);
96 } else {
97 mutex_exit(&pd->pd_lock);
98 }
99 }
100
101 /* kcf_ctx->kc_prov_desc has a hold on pd */
102 KCF_PROV_REFRELE(kcf_ctx->kc_prov_desc);
103
104 kmem_cache_free(kcf_context_cache, kcf_ctx);
105 }
106
107 /*
108 * kmem_cache_alloc constructor for kcf_context structure.
109 */
110 static int
kcf_context_cache_constructor(void * buf,void * cdrarg,int kmflags)111 kcf_context_cache_constructor(void *buf, void *cdrarg, int kmflags)
112 {
113 (void) cdrarg, (void) kmflags;
114 kcf_context_t *kctx = (kcf_context_t *)buf;
115
116 kctx->kc_refcnt = 0;
117
118 return (0);
119 }
120
121 static void
kcf_context_cache_destructor(void * buf,void * cdrarg)122 kcf_context_cache_destructor(void *buf, void *cdrarg)
123 {
124 (void) cdrarg;
125 kcf_context_t *kctx = (kcf_context_t *)buf;
126
127 ASSERT(kctx->kc_refcnt == 0);
128 }
129
130 void
kcf_sched_destroy(void)131 kcf_sched_destroy(void)
132 {
133 if (kcf_context_cache)
134 kmem_cache_destroy(kcf_context_cache);
135 }
136
137 /*
138 * Creates and initializes all the structures needed by the framework.
139 */
140 void
kcf_sched_init(void)141 kcf_sched_init(void)
142 {
143 /*
144 * Create all the kmem caches needed by the framework. We set the
145 * align argument to 64, to get a slab aligned to 64-byte as well as
146 * have the objects (cache_chunksize) to be a 64-byte multiple.
147 * This helps to avoid false sharing as this is the size of the
148 * CPU cache line.
149 */
150 kcf_context_cache = kmem_cache_create("kcf_context_cache",
151 sizeof (struct kcf_context), 64, kcf_context_cache_constructor,
152 kcf_context_cache_destructor, NULL, NULL, NULL, 0);
153 }
154