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. The _pad variant
93 * strips leading zeroes from the b_key.
94 * Note that all numerics in the key token are big-endian,
95 * while the entries in the key block header are little-endian.
96 *
97 * @mex: pointer to user input data
98 * @p: pointer to memory area for the key
99 *
100 * Returns the size of the key area or negative errno value.
101 */
102static inline int zcrypt_type6_mex_key_en(struct ica_rsa_modexpo *mex, void *p)
103{
104	static struct cca_token_hdr static_pub_hdr = {
105		.token_identifier	=  0x1E,
106	};
107	static struct cca_public_sec static_pub_sec = {
108		.section_identifier	=  0x04,
109	};
110	struct {
111		struct T6_keyBlock_hdr t6_hdr;
112		struct cca_token_hdr pubHdr;
113		struct cca_public_sec pubSec;
114		char exponent[0];
115	} __packed *key = p;
116	unsigned char *temp;
117	int i;
118
119	/*
120	 * The inputdatalength was a selection criteria in the dispatching
121	 * function zcrypt_rsa_modexpo(). However, do a plausibility check
122	 * here to make sure the following copy_from_user() can't be utilized
123	 * to compromise the system.
124	 */
125	if (WARN_ON_ONCE(mex->inputdatalength > 512))
126		return -EINVAL;
127
128	memset(key, 0, sizeof(*key));
129
130	key->pubHdr = static_pub_hdr;
131	key->pubSec = static_pub_sec;
132
133	/* key parameter block */
134	temp = key->exponent;
135	if (copy_from_user(temp, mex->b_key, mex->inputdatalength))
136		return -EFAULT;
137	/* Strip leading zeroes from b_key. */
138	for (i = 0; i < mex->inputdatalength; i++)
139		if (temp[i])
140			break;
141	if (i >= mex->inputdatalength)
142		return -EINVAL;
143	memmove(temp, temp + i, mex->inputdatalength - i);
144	temp += mex->inputdatalength - i;
145	/* modulus */
146	if (copy_from_user(temp, mex->n_modulus, mex->inputdatalength))
147		return -EFAULT;
148
149	key->pubSec.modulus_bit_len = 8 * mex->inputdatalength;
150	key->pubSec.modulus_byte_len = mex->inputdatalength;
151	key->pubSec.exponent_len = mex->inputdatalength - i;
152	key->pubSec.section_length = sizeof(key->pubSec) +
153					2*mex->inputdatalength - i;
154	key->pubHdr.token_length =
155		key->pubSec.section_length + sizeof(key->pubHdr);
156	key->t6_hdr.ulen = key->pubHdr.token_length + 4;
157	key->t6_hdr.blen = key->pubHdr.token_length + 6;
158	return sizeof(*key) + 2*mex->inputdatalength - i;
159}
160
161/**
162 * Set up private key fields of a type6 CRT message.
163 * Note that all numerics in the key token are big-endian,
164 * while the entries in the key block header are little-endian.
165 *
166 * @mex: pointer to user input data
167 * @p: pointer to memory area for the key
168 *
169 * Returns the size of the key area or -EFAULT
170 */
171static inline int zcrypt_type6_crt_key(struct ica_rsa_modexpo_crt *crt, void *p)
172{
173	static struct cca_public_sec static_cca_pub_sec = {
174		.section_identifier = 4,
175		.section_length = 0x000f,
176		.exponent_len = 0x0003,
177	};
178	static char pk_exponent[3] = { 0x01, 0x00, 0x01 };
179	struct {
180		struct T6_keyBlock_hdr t6_hdr;
181		struct cca_token_hdr token;
182		struct cca_pvt_ext_CRT_sec pvt;
183		char key_parts[0];
184	} __packed *key = p;
185	struct cca_public_sec *pub;
186	int short_len, long_len, pad_len, key_len, size;
187
188	/*
189	 * The inputdatalength was a selection criteria in the dispatching
190	 * function zcrypt_rsa_crt(). However, do a plausibility check
191	 * here to make sure the following copy_from_user() can't be utilized
192	 * to compromise the system.
193	 */
194	if (WARN_ON_ONCE(crt->inputdatalength > 512))
195		return -EINVAL;
196
197	memset(key, 0, sizeof(*key));
198
199	short_len = (crt->inputdatalength + 1) / 2;
200	long_len = short_len + 8;
201	pad_len = -(3*long_len + 2*short_len) & 7;
202	key_len = 3*long_len + 2*short_len + pad_len + crt->inputdatalength;
203	size = sizeof(*key) + key_len + sizeof(*pub) + 3;
204
205	/* parameter block.key block */
206	key->t6_hdr.blen = size;
207	key->t6_hdr.ulen = size - 2;
208
209	/* key token header */
210	key->token.token_identifier = CCA_TKN_HDR_ID_EXT;
211	key->token.token_length = size - 6;
212
213	/* private section */
214	key->pvt.section_identifier = CCA_PVT_EXT_CRT_SEC_ID_PVT;
215	key->pvt.section_length = sizeof(key->pvt) + key_len;
216	key->pvt.key_format = CCA_PVT_EXT_CRT_SEC_FMT_CL;
217	key->pvt.key_use_flags[0] = CCA_PVT_USAGE_ALL;
218	key->pvt.p_len = key->pvt.dp_len = key->pvt.u_len = long_len;
219	key->pvt.q_len = key->pvt.dq_len = short_len;
220	key->pvt.mod_len = crt->inputdatalength;
221	key->pvt.pad_len = pad_len;
222
223	/* key parts */
224	if (copy_from_user(key->key_parts, crt->np_prime, long_len) ||
225	    copy_from_user(key->key_parts + long_len,
226					crt->nq_prime, short_len) ||
227	    copy_from_user(key->key_parts + long_len + short_len,
228					crt->bp_key, long_len) ||
229	    copy_from_user(key->key_parts + 2*long_len + short_len,
230					crt->bq_key, short_len) ||
231	    copy_from_user(key->key_parts + 2*long_len + 2*short_len,
232					crt->u_mult_inv, long_len))
233		return -EFAULT;
234	memset(key->key_parts + 3*long_len + 2*short_len + pad_len,
235	       0xff, crt->inputdatalength);
236	pub = (struct cca_public_sec *)(key->key_parts + key_len);
237	*pub = static_cca_pub_sec;
238	pub->modulus_bit_len = 8 * crt->inputdatalength;
239	/*
240	 * In a private key, the modulus doesn't appear in the public
241	 * section. So, an arbitrary public exponent of 0x010001 will be
242	 * used.
243	 */
244	memcpy((char *) (pub + 1), pk_exponent, 3);
245	return size;
246}
247
248#endif /* _ZCRYPT_CCA_KEY_H_ */
249