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(ptr, mex->b_key, mex->inputdatalength))
132		return -EFAULT;
133	ptr += mex->inputdatalength;
134	/* modulus */
135	if (copy_from_user(ptr, mex->n_modulus, 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(key->key_parts, crt->np_prime, long_len) ||
213	    copy_from_user(key->key_parts + long_len,
214			   crt->nq_prime, short_len) ||
215	    copy_from_user(key->key_parts + long_len + short_len,
216			   crt->bp_key, long_len) ||
217	    copy_from_user(key->key_parts + 2 * long_len + short_len,
218			   crt->bq_key, short_len) ||
219	    copy_from_user(key->key_parts + 2 * long_len + 2 * short_len,
220			   crt->u_mult_inv, 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