1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3  *  zcrypt 2.1.0
4  *
5  *  Copyright IBM Corp. 2001, 2006
6  *  Author(s): Robert Burroughs
7  *	       Eric Rossman (edrossma@us.ibm.com)
8  *
9  *  Hotplug & misc device support: Jochen Roehrig (roehrig@de.ibm.com)
10  *  Major cleanup & driver split: Martin Schwidefsky <schwidefsky@de.ibm.com>
11  */
12 
13 #ifndef _ZCRYPT_CCA_KEY_H_
14 #define _ZCRYPT_CCA_KEY_H_
15 
16 struct T6_keyBlock_hdr {
17 	unsigned short blen;
18 	unsigned short ulen;
19 	unsigned short flags;
20 };
21 
22 /**
23  * mapping for the cca private ME key token.
24  * Three parts of interest here: the header, the private section and
25  * the public section.
26  *
27  * mapping for the cca key token header
28  */
29 struct cca_token_hdr {
30 	unsigned char  token_identifier;
31 	unsigned char  version;
32 	unsigned short token_length;
33 	unsigned char  reserved[4];
34 } __packed;
35 
36 #define CCA_TKN_HDR_ID_EXT 0x1E
37 
38 #define CCA_PVT_USAGE_ALL 0x80
39 
40 /**
41  * mapping for the cca public section
42  * In a private key, the modulus doesn't appear in the public
43  * section. So, an arbitrary public exponent of 0x010001 will be
44  * used, for a section length of 0x0F always.
45  */
46 struct cca_public_sec {
47 	unsigned char  section_identifier;
48 	unsigned char  version;
49 	unsigned short section_length;
50 	unsigned char  reserved[2];
51 	unsigned short exponent_len;
52 	unsigned short modulus_bit_len;
53 	unsigned short modulus_byte_len;    /* In a private key, this is 0 */
54 } __packed;
55 
56 /**
57  * mapping for the cca private CRT key 'token'
58  * The first three parts (the only parts considered in this release)
59  * are: the header, the private section and the public section.
60  * The header and public section are the same as for the
61  * struct cca_private_ext_ME
62  *
63  * Following the structure are the quantities p, q, dp, dq, u, pad,
64  * and modulus, in that order, where pad_len is the modulo 8
65  * complement of the residue modulo 8 of the sum of
66  * (p_len + q_len + dp_len + dq_len + u_len).
67  */
68 struct cca_pvt_ext_CRT_sec {
69 	unsigned char  section_identifier;
70 	unsigned char  version;
71 	unsigned short section_length;
72 	unsigned char  private_key_hash[20];
73 	unsigned char  reserved1[4];
74 	unsigned char  key_format;
75 	unsigned char  reserved2;
76 	unsigned char  key_name_hash[20];
77 	unsigned char  key_use_flags[4];
78 	unsigned short p_len;
79 	unsigned short q_len;
80 	unsigned short dp_len;
81 	unsigned short dq_len;
82 	unsigned short u_len;
83 	unsigned short mod_len;
84 	unsigned char  reserved3[4];
85 	unsigned short pad_len;
86 	unsigned char  reserved4[52];
87 	unsigned char  confounder[8];
88 } __packed;
89 
90 #define CCA_PVT_EXT_CRT_SEC_ID_PVT 0x08
91 #define CCA_PVT_EXT_CRT_SEC_FMT_CL 0x40
92 
93 /**
94  * Set up private key fields of a type6 MEX message. The _pad variant
95  * strips leading zeroes from the b_key.
96  * Note that all numerics in the key token are big-endian,
97  * while the entries in the key block header are little-endian.
98  *
99  * @mex: pointer to user input data
100  * @p: pointer to memory area for the key
101  *
102  * Returns the size of the key area or negative errno value.
103  */
zcrypt_type6_mex_key_en(struct ica_rsa_modexpo * mex,void * p)104 static inline int zcrypt_type6_mex_key_en(struct ica_rsa_modexpo *mex, void *p)
105 {
106 	static struct cca_token_hdr static_pub_hdr = {
107 		.token_identifier	=  0x1E,
108 	};
109 	static struct cca_public_sec static_pub_sec = {
110 		.section_identifier	=  0x04,
111 	};
112 	struct {
113 		struct T6_keyBlock_hdr t6_hdr;
114 		struct cca_token_hdr pubHdr;
115 		struct cca_public_sec pubSec;
116 		char exponent[0];
117 	} __packed *key = p;
118 	unsigned char *temp;
119 	int i;
120 
121 	/*
122 	 * The inputdatalength was a selection criteria in the dispatching
123 	 * function zcrypt_rsa_modexpo(). However, do a plausibility check
124 	 * here to make sure the following copy_from_user() can't be utilized
125 	 * to compromise the system.
126 	 */
127 	if (WARN_ON_ONCE(mex->inputdatalength > 512))
128 		return -EINVAL;
129 
130 	memset(key, 0, sizeof(*key));
131 
132 	key->pubHdr = static_pub_hdr;
133 	key->pubSec = static_pub_sec;
134 
135 	/* key parameter block */
136 	temp = key->exponent;
137 	if (copy_from_user(temp, mex->b_key, mex->inputdatalength))
138 		return -EFAULT;
139 	/* Strip leading zeroes from b_key. */
140 	for (i = 0; i < mex->inputdatalength; i++)
141 		if (temp[i])
142 			break;
143 	if (i >= mex->inputdatalength)
144 		return -EINVAL;
145 	memmove(temp, temp + i, mex->inputdatalength - i);
146 	temp += mex->inputdatalength - i;
147 	/* modulus */
148 	if (copy_from_user(temp, mex->n_modulus, mex->inputdatalength))
149 		return -EFAULT;
150 
151 	key->pubSec.modulus_bit_len = 8 * mex->inputdatalength;
152 	key->pubSec.modulus_byte_len = mex->inputdatalength;
153 	key->pubSec.exponent_len = mex->inputdatalength - i;
154 	key->pubSec.section_length = sizeof(key->pubSec) +
155 					2*mex->inputdatalength - i;
156 	key->pubHdr.token_length =
157 		key->pubSec.section_length + sizeof(key->pubHdr);
158 	key->t6_hdr.ulen = key->pubHdr.token_length + 4;
159 	key->t6_hdr.blen = key->pubHdr.token_length + 6;
160 	return sizeof(*key) + 2*mex->inputdatalength - i;
161 }
162 
163 /**
164  * Set up private key fields of a type6 CRT message.
165  * Note that all numerics in the key token are big-endian,
166  * while the entries in the key block header are little-endian.
167  *
168  * @mex: pointer to user input data
169  * @p: pointer to memory area for the key
170  *
171  * Returns the size of the key area or -EFAULT
172  */
zcrypt_type6_crt_key(struct ica_rsa_modexpo_crt * crt,void * p)173 static inline int zcrypt_type6_crt_key(struct ica_rsa_modexpo_crt *crt, void *p)
174 {
175 	static struct cca_public_sec static_cca_pub_sec = {
176 		.section_identifier = 4,
177 		.section_length = 0x000f,
178 		.exponent_len = 0x0003,
179 	};
180 	static char pk_exponent[3] = { 0x01, 0x00, 0x01 };
181 	struct {
182 		struct T6_keyBlock_hdr t6_hdr;
183 		struct cca_token_hdr token;
184 		struct cca_pvt_ext_CRT_sec pvt;
185 		char key_parts[0];
186 	} __packed *key = p;
187 	struct cca_public_sec *pub;
188 	int short_len, long_len, pad_len, key_len, size;
189 
190 	/*
191 	 * The inputdatalength was a selection criteria in the dispatching
192 	 * function zcrypt_rsa_crt(). However, do a plausibility check
193 	 * here to make sure the following copy_from_user() can't be utilized
194 	 * to compromise the system.
195 	 */
196 	if (WARN_ON_ONCE(crt->inputdatalength > 512))
197 		return -EINVAL;
198 
199 	memset(key, 0, sizeof(*key));
200 
201 	short_len = (crt->inputdatalength + 1) / 2;
202 	long_len = short_len + 8;
203 	pad_len = -(3*long_len + 2*short_len) & 7;
204 	key_len = 3*long_len + 2*short_len + pad_len + crt->inputdatalength;
205 	size = sizeof(*key) + key_len + sizeof(*pub) + 3;
206 
207 	/* parameter block.key block */
208 	key->t6_hdr.blen = size;
209 	key->t6_hdr.ulen = size - 2;
210 
211 	/* key token header */
212 	key->token.token_identifier = CCA_TKN_HDR_ID_EXT;
213 	key->token.token_length = size - 6;
214 
215 	/* private section */
216 	key->pvt.section_identifier = CCA_PVT_EXT_CRT_SEC_ID_PVT;
217 	key->pvt.section_length = sizeof(key->pvt) + key_len;
218 	key->pvt.key_format = CCA_PVT_EXT_CRT_SEC_FMT_CL;
219 	key->pvt.key_use_flags[0] = CCA_PVT_USAGE_ALL;
220 	key->pvt.p_len = key->pvt.dp_len = key->pvt.u_len = long_len;
221 	key->pvt.q_len = key->pvt.dq_len = short_len;
222 	key->pvt.mod_len = crt->inputdatalength;
223 	key->pvt.pad_len = pad_len;
224 
225 	/* key parts */
226 	if (copy_from_user(key->key_parts, crt->np_prime, long_len) ||
227 	    copy_from_user(key->key_parts + long_len,
228 					crt->nq_prime, short_len) ||
229 	    copy_from_user(key->key_parts + long_len + short_len,
230 					crt->bp_key, long_len) ||
231 	    copy_from_user(key->key_parts + 2*long_len + short_len,
232 					crt->bq_key, short_len) ||
233 	    copy_from_user(key->key_parts + 2*long_len + 2*short_len,
234 					crt->u_mult_inv, long_len))
235 		return -EFAULT;
236 	memset(key->key_parts + 3*long_len + 2*short_len + pad_len,
237 	       0xff, crt->inputdatalength);
238 	pub = (struct cca_public_sec *)(key->key_parts + key_len);
239 	*pub = static_cca_pub_sec;
240 	pub->modulus_bit_len = 8 * crt->inputdatalength;
241 	/*
242 	 * In a private key, the modulus doesn't appear in the public
243 	 * section. So, an arbitrary public exponent of 0x010001 will be
244 	 * used.
245 	 */
246 	memcpy((char *) (pub + 1), pk_exponent, 3);
247 	return size;
248 }
249 
250 #endif /* _ZCRYPT_CCA_KEY_H_ */
251