1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or https://opensource.org/licenses/CDDL-1.0.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #include <sys/zfs_context.h>
27 #include <sys/crypto/common.h>
28 #include <sys/crypto/impl.h>
29 #include <sys/crypto/api.h>
30 #include <sys/crypto/spi.h>
31 #include <sys/crypto/sched_impl.h>
32 
33 /*
34  * Encryption and decryption routines.
35  */
36 
37 
38 /*
39  * crypto_encrypt()
40  *
41  * Arguments:
42  *	sid:	session id
43  *	mech:	crypto_mechanism_t pointer.
44  *		mech_type is a valid value previously returned by
45  *		crypto_mech2id();
46  *		When the mech's parameter is not NULL, its definition depends
47  *		on the standard definition of the mechanism.
48  *	key:	pointer to a crypto_key_t structure.
49  *	plaintext: The message to be encrypted
50  *	ciphertext: Storage for the encrypted message. The length needed
51  *		depends on the mechanism, and the plaintext's size.
52  *	tmpl:	a crypto_ctx_template_t, opaque template of a context of an
53  *		encryption with the 'mech' using 'key'. 'tmpl' is created by
54  *		a previous call to crypto_create_ctx_template().
55  *
56  * Description:
57  *	Asynchronously submits a request for, or synchronously performs a
58  *	single-part encryption of 'plaintext' with the mechanism 'mech', using
59  *	the key 'key'.
60  *	When complete and successful, 'ciphertext' will contain the encrypted
61  *	message.
62  *	Relies on the KCF scheduler to pick a provider.
63  *
64  * Returns:
65  *	See comment in the beginning of the file.
66  */
67 int
68 crypto_encrypt(crypto_mechanism_t *mech, crypto_data_t *plaintext,
69     crypto_key_t *key, crypto_ctx_template_t tmpl, crypto_data_t *ciphertext)
70 {
71 	int error;
72 	kcf_mech_entry_t *me;
73 	kcf_provider_desc_t *pd;
74 	kcf_ctx_template_t *ctx_tmpl;
75 	crypto_spi_ctx_template_t spi_ctx_tmpl = NULL;
76 	kcf_prov_tried_t *list = NULL;
77 
78 retry:
79 	/* pd is returned held */
80 	if ((pd = kcf_get_mech_provider(mech->cm_type, &me, &error,
81 	    list, CRYPTO_FG_ENCRYPT_ATOMIC)) == NULL) {
82 		if (list != NULL)
83 			kcf_free_triedlist(list);
84 		return (error);
85 	}
86 
87 	if (((ctx_tmpl = (kcf_ctx_template_t *)tmpl) != NULL))
88 		spi_ctx_tmpl = ctx_tmpl->ct_prov_tmpl;
89 
90 	crypto_mechanism_t lmech = *mech;
91 	KCF_SET_PROVIDER_MECHNUM(mech->cm_type, pd, &lmech);
92 	error = KCF_PROV_ENCRYPT_ATOMIC(pd, &lmech, key,
93 	    plaintext, ciphertext, spi_ctx_tmpl);
94 
95 	if (error != CRYPTO_SUCCESS && IS_RECOVERABLE(error)) {
96 		/* Add pd to the linked list of providers tried. */
97 		if (kcf_insert_triedlist(&list, pd, KM_SLEEP) != NULL)
98 			goto retry;
99 	}
100 
101 	if (list != NULL)
102 		kcf_free_triedlist(list);
103 
104 	KCF_PROV_REFRELE(pd);
105 	return (error);
106 }
107 
108 /*
109  * crypto_decrypt_prov()
110  *
111  * Arguments:
112  *	pd:	provider descriptor
113  *	sid:	session id
114  *	mech:	crypto_mechanism_t pointer.
115  *		mech_type is a valid value previously returned by
116  *		crypto_mech2id();
117  *		When the mech's parameter is not NULL, its definition depends
118  *		on the standard definition of the mechanism.
119  *	key:	pointer to a crypto_key_t structure.
120  *	ciphertext: The message to be encrypted
121  *	plaintext: Storage for the encrypted message. The length needed
122  *		depends on the mechanism, and the plaintext's size.
123  *	tmpl:	a crypto_ctx_template_t, opaque template of a context of an
124  *		encryption with the 'mech' using 'key'. 'tmpl' is created by
125  *		a previous call to crypto_create_ctx_template().
126  *
127  * Description:
128  *	Asynchronously submits a request for, or synchronously performs a
129  *	single-part decryption of 'ciphertext' with the mechanism 'mech', using
130  *	the key 'key'.
131  *	When complete and successful, 'plaintext' will contain the decrypted
132  *	message.
133  *	Relies on the KCF scheduler to choose a provider.
134  *
135  * Returns:
136  *	See comment in the beginning of the file.
137  */
138 int
139 crypto_decrypt(crypto_mechanism_t *mech, crypto_data_t *ciphertext,
140     crypto_key_t *key, crypto_ctx_template_t tmpl, crypto_data_t *plaintext)
141 {
142 	int error;
143 	kcf_mech_entry_t *me;
144 	kcf_provider_desc_t *pd;
145 	kcf_ctx_template_t *ctx_tmpl;
146 	crypto_spi_ctx_template_t spi_ctx_tmpl = NULL;
147 	kcf_prov_tried_t *list = NULL;
148 
149 retry:
150 	/* pd is returned held */
151 	if ((pd = kcf_get_mech_provider(mech->cm_type, &me, &error,
152 	    list, CRYPTO_FG_DECRYPT_ATOMIC)) == NULL) {
153 		if (list != NULL)
154 			kcf_free_triedlist(list);
155 		return (error);
156 	}
157 
158 	if (((ctx_tmpl = (kcf_ctx_template_t *)tmpl) != NULL))
159 		spi_ctx_tmpl = ctx_tmpl->ct_prov_tmpl;
160 
161 	crypto_mechanism_t lmech = *mech;
162 	KCF_SET_PROVIDER_MECHNUM(mech->cm_type, pd, &lmech);
163 
164 	error = KCF_PROV_DECRYPT_ATOMIC(pd, &lmech, key,
165 	    ciphertext, plaintext, spi_ctx_tmpl);
166 
167 	if (error != CRYPTO_SUCCESS && IS_RECOVERABLE(error)) {
168 		/* Add pd to the linked list of providers tried. */
169 		if (kcf_insert_triedlist(&list, pd, KM_SLEEP) != NULL)
170 			goto retry;
171 	}
172 
173 	if (list != NULL)
174 		kcf_free_triedlist(list);
175 
176 	KCF_PROV_REFRELE(pd);
177 	return (error);
178 }
179 
180 #if defined(_KERNEL)
181 EXPORT_SYMBOL(crypto_encrypt);
182 EXPORT_SYMBOL(crypto_decrypt);
183 #endif
184