1/* SPDX-License-Identifier: GPL-2.0+ */
2/*
3 * Copyright IBM Corp. 2001, 2006
4 * Author(s): Robert Burroughs
5 * Eric Rossman (edrossma@us.ibm.com)
6 *
7 * Hotplug & misc device support: Jochen Roehrig (roehrig@de.ibm.com)
8 * Major cleanup & driver split: Martin Schwidefsky <schwidefsky@de.ibm.com>
9 */
10
11#ifndef _ZCRYPT_CCA_KEY_H_
12#define _ZCRYPT_CCA_KEY_H_
13
14struct t6_keyblock_hdr {
15 unsigned short blen;
16 unsigned short ulen;
17 unsigned short flags;
18};
19
20/**
21 * mapping for the cca private ME key token.
22 * Three parts of interest here: the header, the private section and
23 * the public section.
24 *
25 * mapping for the cca key token header
26 */
27struct cca_token_hdr {
28 unsigned char token_identifier;
29 unsigned char version;
30 unsigned short token_length;
31 unsigned char reserved[4];
32} __packed;
33
34#define CCA_TKN_HDR_ID_EXT 0x1E
35
36#define CCA_PVT_USAGE_ALL 0x80
37
38/**
39 * mapping for the cca public section
40 * In a private key, the modulus doesn't appear in the public
41 * section. So, an arbitrary public exponent of 0x010001 will be
42 * used, for a section length of 0x0F always.
43 */
44struct cca_public_sec {
45 unsigned char section_identifier;
46 unsigned char version;
47 unsigned short section_length;
48 unsigned char reserved[2];
49 unsigned short exponent_len;
50 unsigned short modulus_bit_len;
51 unsigned short modulus_byte_len; /* In a private key, this is 0 */
52} __packed;
53
54/**
55 * mapping for the cca private CRT key 'token'
56 * The first three parts (the only parts considered in this release)
57 * are: the header, the private section and the public section.
58 * The header and public section are the same as for the
59 * struct cca_private_ext_ME
60 *
61 * Following the structure are the quantities p, q, dp, dq, u, pad,
62 * and modulus, in that order, where pad_len is the modulo 8
63 * complement of the residue modulo 8 of the sum of
64 * (p_len + q_len + dp_len + dq_len + u_len).
65 */
66struct cca_pvt_ext_crt_sec {
67 unsigned char section_identifier;
68 unsigned char version;
69 unsigned short section_length;
70 unsigned char private_key_hash[20];
71 unsigned char reserved1[4];
72 unsigned char key_format;
73 unsigned char reserved2;
74 unsigned char key_name_hash[20];
75 unsigned char key_use_flags[4];
76 unsigned short p_len;
77 unsigned short q_len;
78 unsigned short dp_len;
79 unsigned short dq_len;
80 unsigned short u_len;
81 unsigned short mod_len;
82 unsigned char reserved3[4];
83 unsigned short pad_len;
84 unsigned char reserved4[52];
85 unsigned char confounder[8];
86} __packed;
87
88#define CCA_PVT_EXT_CRT_SEC_ID_PVT 0x08
89#define CCA_PVT_EXT_CRT_SEC_FMT_CL 0x40
90
91/**
92 * Set up private key fields of a type6 MEX message.
93 *
94 * @mex: pointer to user input data
95 * @p: pointer to memory area for the key
96 *
97 * Returns the size of the key area or negative errno value.
98 */
99static inline int zcrypt_type6_mex_key_en(struct ica_rsa_modexpo *mex, void *p)
100{
101 static struct cca_token_hdr static_pub_hdr = {
102 .token_identifier = 0x1E,
103 };
104 static struct cca_public_sec static_pub_sec = {
105 .section_identifier = 0x04,
106 };
107 struct {
108 struct t6_keyblock_hdr t6_hdr;
109 struct cca_token_hdr pubhdr;
110 struct cca_public_sec pubsec;
111 char exponent[];
112 } __packed *key = p;
113 unsigned char *ptr;
114
115 /*
116 * The inputdatalength was a selection criteria in the dispatching
117 * function zcrypt_rsa_modexpo(). However, do a plausibility check
118 * here to make sure the following copy_from_user() can't be utilized
119 * to compromise the system.
120 */
121 if (WARN_ON_ONCE(mex->inputdatalength > 512))
122 return -EINVAL;
123
124 memset(key, 0, sizeof(*key));
125
126 key->pubhdr = static_pub_hdr;
127 key->pubsec = static_pub_sec;
128
129 /* key parameter block */
130 ptr = key->exponent;
131 if (copy_from_user(to: ptr, from: mex->b_key, n: mex->inputdatalength))
132 return -EFAULT;
133 ptr += mex->inputdatalength;
134 /* modulus */
135 if (copy_from_user(to: ptr, from: mex->n_modulus, n: mex->inputdatalength))
136 return -EFAULT;
137
138 key->pubsec.modulus_bit_len = 8 * mex->inputdatalength;
139 key->pubsec.modulus_byte_len = mex->inputdatalength;
140 key->pubsec.exponent_len = mex->inputdatalength;
141 key->pubsec.section_length = sizeof(key->pubsec) +
142 2 * mex->inputdatalength;
143 key->pubhdr.token_length =
144 key->pubsec.section_length + sizeof(key->pubhdr);
145 key->t6_hdr.ulen = key->pubhdr.token_length + 4;
146 key->t6_hdr.blen = key->pubhdr.token_length + 6;
147
148 return sizeof(*key) + 2 * mex->inputdatalength;
149}
150
151/**
152 * Set up private key fields of a type6 CRT message.
153 *
154 * @mex: pointer to user input data
155 * @p: pointer to memory area for the key
156 *
157 * Returns the size of the key area or -EFAULT
158 */
159static inline int zcrypt_type6_crt_key(struct ica_rsa_modexpo_crt *crt, void *p)
160{
161 static struct cca_public_sec static_cca_pub_sec = {
162 .section_identifier = 4,
163 .section_length = 0x000f,
164 .exponent_len = 0x0003,
165 };
166 static char pk_exponent[3] = { 0x01, 0x00, 0x01 };
167 struct {
168 struct t6_keyblock_hdr t6_hdr;
169 struct cca_token_hdr token;
170 struct cca_pvt_ext_crt_sec pvt;
171 char key_parts[];
172 } __packed *key = p;
173 struct cca_public_sec *pub;
174 int short_len, long_len, pad_len, key_len, size;
175
176 /*
177 * The inputdatalength was a selection criteria in the dispatching
178 * function zcrypt_rsa_crt(). However, do a plausibility check
179 * here to make sure the following copy_from_user() can't be utilized
180 * to compromise the system.
181 */
182 if (WARN_ON_ONCE(crt->inputdatalength > 512))
183 return -EINVAL;
184
185 memset(key, 0, sizeof(*key));
186
187 short_len = (crt->inputdatalength + 1) / 2;
188 long_len = short_len + 8;
189 pad_len = -(3 * long_len + 2 * short_len) & 7;
190 key_len = 3 * long_len + 2 * short_len + pad_len + crt->inputdatalength;
191 size = sizeof(*key) + key_len + sizeof(*pub) + 3;
192
193 /* parameter block.key block */
194 key->t6_hdr.blen = size;
195 key->t6_hdr.ulen = size - 2;
196
197 /* key token header */
198 key->token.token_identifier = CCA_TKN_HDR_ID_EXT;
199 key->token.token_length = size - 6;
200
201 /* private section */
202 key->pvt.section_identifier = CCA_PVT_EXT_CRT_SEC_ID_PVT;
203 key->pvt.section_length = sizeof(key->pvt) + key_len;
204 key->pvt.key_format = CCA_PVT_EXT_CRT_SEC_FMT_CL;
205 key->pvt.key_use_flags[0] = CCA_PVT_USAGE_ALL;
206 key->pvt.p_len = key->pvt.dp_len = key->pvt.u_len = long_len;
207 key->pvt.q_len = key->pvt.dq_len = short_len;
208 key->pvt.mod_len = crt->inputdatalength;
209 key->pvt.pad_len = pad_len;
210
211 /* key parts */
212 if (copy_from_user(to: key->key_parts, from: crt->np_prime, n: long_len) ||
213 copy_from_user(to: key->key_parts + long_len,
214 from: crt->nq_prime, n: short_len) ||
215 copy_from_user(to: key->key_parts + long_len + short_len,
216 from: crt->bp_key, n: long_len) ||
217 copy_from_user(to: key->key_parts + 2 * long_len + short_len,
218 from: crt->bq_key, n: short_len) ||
219 copy_from_user(to: key->key_parts + 2 * long_len + 2 * short_len,
220 from: crt->u_mult_inv, n: long_len))
221 return -EFAULT;
222 memset(key->key_parts + 3 * long_len + 2 * short_len + pad_len,
223 0xff, crt->inputdatalength);
224 pub = (struct cca_public_sec *)(key->key_parts + key_len);
225 *pub = static_cca_pub_sec;
226 pub->modulus_bit_len = 8 * crt->inputdatalength;
227 /*
228 * In a private key, the modulus doesn't appear in the public
229 * section. So, an arbitrary public exponent of 0x010001 will be
230 * used.
231 */
232 memcpy((char *)(pub + 1), pk_exponent, 3);
233
234 return size;
235}
236
237#endif /* _ZCRYPT_CCA_KEY_H_ */
238

source code of linux/drivers/s390/crypto/zcrypt_cca_key.h