1 /*
2 * This file and its contents are supplied under the terms of the
3 * Common Development and Distribution License ("CDDL"), version 1.0.
4 * You may only use this file in accordance with the terms of version
5 * 1.0 of the CDDL.
6 *
7 * A full copy of the text of the CDDL should have accompanied this
8 * source. A copy of the CDDL is also available via the Internet at
9 * http://www.illumos.org/license/CDDL.
10 */
11
12 /*
13 * Copyright 2017 Nexenta Systems, Inc. All rights reserved.
14 */
15
16 /*
17 * Helper functions for SMB signing using the
18 * Kernel Cryptographic Framework (KCF)
19 *
20 * There are two implementations of these functions:
21 * This one (for kernel) and another for user space:
22 * See: lib/smbclnt/libfknsmb/common/fksmb_sign_pkcs.c
23 */
24
25 #include <sys/types.h>
26 #include <sys/kmem.h>
27 #include <sys/sunddi.h>
28 #include <sys/crypto/api.h>
29 #include <netsmb/smb_signing.h>
30
31 /*
32 * SMB1 signing helpers:
33 * (getmech, init, update, final)
34 */
35
36 int
37 smb_md5_getmech(smb_sign_mech_t *mech)
38 {
39 crypto_mech_type_t t;
40
41 t = crypto_mech2id(SUN_CKM_MD5);
42 if (t == CRYPTO_MECH_INVALID)
43 return (-1);
44 mech->cm_type = t;
45 return (0);
46 }
47
48 /*
49 * Start the KCF session, load the key
50 */
51 int
52 smb_md5_init(smb_sign_ctx_t *ctxp, smb_sign_mech_t *mech)
53 {
54 int rv;
55
56 rv = crypto_digest_init(mech, ctxp, NULL);
57
58 return (rv == CRYPTO_SUCCESS ? 0 : -1);
59 }
60
61 /*
62 * Digest one segment
63 */
64 int
65 smb_md5_update(smb_sign_ctx_t ctx, void *buf, size_t len)
66 {
67 crypto_data_t data;
68 int rv;
69
70 bzero(&data, sizeof (data));
71 data.cd_format = CRYPTO_DATA_RAW;
72 data.cd_length = len;
73 data.cd_raw.iov_base = buf;
74 data.cd_raw.iov_len = len;
75
76 rv = crypto_digest_update(ctx, &data, 0);
77
78 return (rv == CRYPTO_SUCCESS ? 0 : -1);
79 }
80
81 /*
82 * Get the final digest.
83 */
84 int
85 smb_md5_final(smb_sign_ctx_t ctx, uint8_t *digest16)
86 {
87 crypto_data_t out;
88 int rv;
89
90 bzero(&out, sizeof (out));
91 out.cd_format = CRYPTO_DATA_RAW;
92 out.cd_length = MD5_DIGEST_LENGTH;
93 out.cd_raw.iov_len = MD5_DIGEST_LENGTH;
94 out.cd_raw.iov_base = (void *)digest16;
95
96 rv = crypto_digest_final(ctx, &out, 0);
97
98 return (rv == CRYPTO_SUCCESS ? 0 : -1);
99 }
100
101 /*
102 * SMB2 signing helpers:
103 * (getmech, init, update, final)
104 */
105
106 int
107 smb2_hmac_getmech(smb_sign_mech_t *mech)
108 {
109 crypto_mech_type_t t;
110
111 t = crypto_mech2id(SUN_CKM_SHA256_HMAC);
112 if (t == CRYPTO_MECH_INVALID)
113 return (-1);
114 mech->cm_type = t;
115 return (0);
116 }
117
118 /*
119 * Start the KCF session, load the key
120 */
121 int
122 smb2_hmac_init(smb_sign_ctx_t *ctxp, smb_sign_mech_t *mech,
123 uint8_t *key, size_t key_len)
124 {
125 crypto_key_t ckey;
126 int rv;
127
128 bzero(&ckey, sizeof (ckey));
129 ckey.ck_format = CRYPTO_KEY_RAW;
130 ckey.ck_data = key;
131 ckey.ck_length = key_len * 8; /* in bits */
132
133 rv = crypto_mac_init(mech, &ckey, NULL, ctxp, NULL);
134
135 return (rv == CRYPTO_SUCCESS ? 0 : -1);
136 }
137
138 /*
139 * Digest one segment
140 */
141 int
142 smb2_hmac_update(smb_sign_ctx_t ctx, uint8_t *in, size_t len)
143 {
144 crypto_data_t data;
145 int rv;
146
147 bzero(&data, sizeof (data));
148 data.cd_format = CRYPTO_DATA_RAW;
149 data.cd_length = len;
150 data.cd_raw.iov_base = (void *)in;
151 data.cd_raw.iov_len = len;
152
153 rv = crypto_mac_update(ctx, &data, 0);
154
155 return (rv == CRYPTO_SUCCESS ? 0 : -1);
156 }
157
158 /*
159 * Note, the SMB2 signature is the first 16 bytes of the
160 * 32-byte SHA256 HMAC digest.
161 */
162 int
163 smb2_hmac_final(smb_sign_ctx_t ctx, uint8_t *digest16)
164 {
165 uint8_t full_digest[SHA256_DIGEST_LENGTH];
166 crypto_data_t out;
167 int rv;
168
169 bzero(&out, sizeof (out));
170 out.cd_format = CRYPTO_DATA_RAW;
171 out.cd_length = SHA256_DIGEST_LENGTH;
172 out.cd_raw.iov_len = SHA256_DIGEST_LENGTH;
173 out.cd_raw.iov_base = (void *)full_digest;
174
175 rv = crypto_mac_final(ctx, &out, 0);
176 if (rv == CRYPTO_SUCCESS)
177 bcopy(full_digest, digest16, 16);
178
179 return (rv == CRYPTO_SUCCESS ? 0 : -1);
180 }