xref: /openbmc/linux/drivers/crypto/nx/nx-sha256.c (revision ee89bd6b)
1 /**
2  * SHA-256 routines supporting the Power 7+ Nest Accelerators driver
3  *
4  * Copyright (C) 2011-2012 International Business Machines Inc.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; version 2 only.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
18  *
19  * Author: Kent Yoder <yoder1@us.ibm.com>
20  */
21 
22 #include <crypto/internal/hash.h>
23 #include <crypto/sha.h>
24 #include <linux/module.h>
25 #include <asm/vio.h>
26 
27 #include "nx_csbcpb.h"
28 #include "nx.h"
29 
30 
31 static int nx_sha256_init(struct shash_desc *desc)
32 {
33 	struct sha256_state *sctx = shash_desc_ctx(desc);
34 	struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&desc->tfm->base);
35 	struct nx_sg *out_sg;
36 
37 	nx_ctx_init(nx_ctx, HCOP_FC_SHA);
38 
39 	memset(sctx, 0, sizeof *sctx);
40 
41 	nx_ctx->ap = &nx_ctx->props[NX_PROPS_SHA256];
42 
43 	NX_CPB_SET_DIGEST_SIZE(nx_ctx->csbcpb, NX_DS_SHA256);
44 	out_sg = nx_build_sg_list(nx_ctx->out_sg, (u8 *)sctx->state,
45 				  SHA256_DIGEST_SIZE, nx_ctx->ap->sglen);
46 	nx_ctx->op.outlen = (nx_ctx->out_sg - out_sg) * sizeof(struct nx_sg);
47 
48 	return 0;
49 }
50 
51 static int nx_sha256_update(struct shash_desc *desc, const u8 *data,
52 			    unsigned int len)
53 {
54 	struct sha256_state *sctx = shash_desc_ctx(desc);
55 	struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&desc->tfm->base);
56 	struct nx_csbcpb *csbcpb = (struct nx_csbcpb *)nx_ctx->csbcpb;
57 	struct nx_sg *in_sg;
58 	u64 to_process, leftover;
59 	int rc = 0;
60 
61 	if (NX_CPB_FDM(csbcpb) & NX_FDM_CONTINUATION) {
62 		/* we've hit the nx chip previously and we're updating again,
63 		 * so copy over the partial digest */
64 		memcpy(csbcpb->cpb.sha256.input_partial_digest,
65 		       csbcpb->cpb.sha256.message_digest, SHA256_DIGEST_SIZE);
66 	}
67 
68 	/* 2 cases for total data len:
69 	 *  1: <= SHA256_BLOCK_SIZE: copy into state, return 0
70 	 *  2: > SHA256_BLOCK_SIZE: process X blocks, copy in leftover
71 	 */
72 	if (len + sctx->count < SHA256_BLOCK_SIZE) {
73 		memcpy(sctx->buf + sctx->count, data, len);
74 		sctx->count += len;
75 		goto out;
76 	}
77 
78 	/* to_process: the SHA256_BLOCK_SIZE data chunk to process in this
79 	 * update */
80 	to_process = (sctx->count + len) & ~(SHA256_BLOCK_SIZE - 1);
81 	leftover = (sctx->count + len) & (SHA256_BLOCK_SIZE - 1);
82 
83 	if (sctx->count) {
84 		in_sg = nx_build_sg_list(nx_ctx->in_sg, (u8 *)sctx->buf,
85 					 sctx->count, nx_ctx->ap->sglen);
86 		in_sg = nx_build_sg_list(in_sg, (u8 *)data,
87 					 to_process - sctx->count,
88 					 nx_ctx->ap->sglen);
89 		nx_ctx->op.inlen = (nx_ctx->in_sg - in_sg) *
90 					sizeof(struct nx_sg);
91 	} else {
92 		in_sg = nx_build_sg_list(nx_ctx->in_sg, (u8 *)data,
93 					 to_process, nx_ctx->ap->sglen);
94 		nx_ctx->op.inlen = (nx_ctx->in_sg - in_sg) *
95 					sizeof(struct nx_sg);
96 	}
97 
98 	NX_CPB_FDM(csbcpb) |= NX_FDM_INTERMEDIATE;
99 
100 	if (!nx_ctx->op.inlen || !nx_ctx->op.outlen) {
101 		rc = -EINVAL;
102 		goto out;
103 	}
104 
105 	rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
106 			   desc->flags & CRYPTO_TFM_REQ_MAY_SLEEP);
107 	if (rc)
108 		goto out;
109 
110 	atomic_inc(&(nx_ctx->stats->sha256_ops));
111 
112 	/* copy the leftover back into the state struct */
113 	if (leftover)
114 		memcpy(sctx->buf, data + len - leftover, leftover);
115 	sctx->count = leftover;
116 
117 	csbcpb->cpb.sha256.message_bit_length += (u64)
118 		(csbcpb->cpb.sha256.spbc * 8);
119 
120 	/* everything after the first update is continuation */
121 	NX_CPB_FDM(csbcpb) |= NX_FDM_CONTINUATION;
122 out:
123 	return rc;
124 }
125 
126 static int nx_sha256_final(struct shash_desc *desc, u8 *out)
127 {
128 	struct sha256_state *sctx = shash_desc_ctx(desc);
129 	struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&desc->tfm->base);
130 	struct nx_csbcpb *csbcpb = (struct nx_csbcpb *)nx_ctx->csbcpb;
131 	struct nx_sg *in_sg, *out_sg;
132 	int rc;
133 
134 
135 	if (NX_CPB_FDM(csbcpb) & NX_FDM_CONTINUATION) {
136 		/* we've hit the nx chip previously, now we're finalizing,
137 		 * so copy over the partial digest */
138 		memcpy(csbcpb->cpb.sha256.input_partial_digest,
139 		       csbcpb->cpb.sha256.message_digest, SHA256_DIGEST_SIZE);
140 	}
141 
142 	/* final is represented by continuing the operation and indicating that
143 	 * this is not an intermediate operation */
144 	NX_CPB_FDM(csbcpb) &= ~NX_FDM_INTERMEDIATE;
145 
146 	csbcpb->cpb.sha256.message_bit_length += (u64)(sctx->count * 8);
147 
148 	in_sg = nx_build_sg_list(nx_ctx->in_sg, (u8 *)sctx->buf,
149 				 sctx->count, nx_ctx->ap->sglen);
150 	out_sg = nx_build_sg_list(nx_ctx->out_sg, out, SHA256_DIGEST_SIZE,
151 				  nx_ctx->ap->sglen);
152 	nx_ctx->op.inlen = (nx_ctx->in_sg - in_sg) * sizeof(struct nx_sg);
153 	nx_ctx->op.outlen = (nx_ctx->out_sg - out_sg) * sizeof(struct nx_sg);
154 
155 	if (!nx_ctx->op.outlen) {
156 		rc = -EINVAL;
157 		goto out;
158 	}
159 
160 	rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
161 			   desc->flags & CRYPTO_TFM_REQ_MAY_SLEEP);
162 	if (rc)
163 		goto out;
164 
165 	atomic_inc(&(nx_ctx->stats->sha256_ops));
166 
167 	atomic64_add(csbcpb->cpb.sha256.message_bit_length / 8,
168 		     &(nx_ctx->stats->sha256_bytes));
169 	memcpy(out, csbcpb->cpb.sha256.message_digest, SHA256_DIGEST_SIZE);
170 out:
171 	return rc;
172 }
173 
174 static int nx_sha256_export(struct shash_desc *desc, void *out)
175 {
176 	struct sha256_state *sctx = shash_desc_ctx(desc);
177 	struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&desc->tfm->base);
178 	struct nx_csbcpb *csbcpb = (struct nx_csbcpb *)nx_ctx->csbcpb;
179 	struct sha256_state *octx = out;
180 
181 	octx->count = sctx->count +
182 		      (csbcpb->cpb.sha256.message_bit_length / 8);
183 	memcpy(octx->buf, sctx->buf, sizeof(octx->buf));
184 
185 	/* if no data has been processed yet, we need to export SHA256's
186 	 * initial data, in case this context gets imported into a software
187 	 * context */
188 	if (csbcpb->cpb.sha256.message_bit_length)
189 		memcpy(octx->state, csbcpb->cpb.sha256.message_digest,
190 		       SHA256_DIGEST_SIZE);
191 	else {
192 		octx->state[0] = SHA256_H0;
193 		octx->state[1] = SHA256_H1;
194 		octx->state[2] = SHA256_H2;
195 		octx->state[3] = SHA256_H3;
196 		octx->state[4] = SHA256_H4;
197 		octx->state[5] = SHA256_H5;
198 		octx->state[6] = SHA256_H6;
199 		octx->state[7] = SHA256_H7;
200 	}
201 
202 	return 0;
203 }
204 
205 static int nx_sha256_import(struct shash_desc *desc, const void *in)
206 {
207 	struct sha256_state *sctx = shash_desc_ctx(desc);
208 	struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&desc->tfm->base);
209 	struct nx_csbcpb *csbcpb = (struct nx_csbcpb *)nx_ctx->csbcpb;
210 	const struct sha256_state *ictx = in;
211 
212 	memcpy(sctx->buf, ictx->buf, sizeof(ictx->buf));
213 
214 	sctx->count = ictx->count & 0x3f;
215 	csbcpb->cpb.sha256.message_bit_length = (ictx->count & ~0x3f) * 8;
216 
217 	if (csbcpb->cpb.sha256.message_bit_length) {
218 		memcpy(csbcpb->cpb.sha256.message_digest, ictx->state,
219 		       SHA256_DIGEST_SIZE);
220 
221 		NX_CPB_FDM(csbcpb) |= NX_FDM_CONTINUATION;
222 		NX_CPB_FDM(csbcpb) |= NX_FDM_INTERMEDIATE;
223 	}
224 
225 	return 0;
226 }
227 
228 struct shash_alg nx_shash_sha256_alg = {
229 	.digestsize = SHA256_DIGEST_SIZE,
230 	.init       = nx_sha256_init,
231 	.update     = nx_sha256_update,
232 	.final      = nx_sha256_final,
233 	.export     = nx_sha256_export,
234 	.import     = nx_sha256_import,
235 	.descsize   = sizeof(struct sha256_state),
236 	.statesize  = sizeof(struct sha256_state),
237 	.base       = {
238 		.cra_name        = "sha256",
239 		.cra_driver_name = "sha256-nx",
240 		.cra_priority    = 300,
241 		.cra_flags       = CRYPTO_ALG_TYPE_SHASH,
242 		.cra_blocksize   = SHA256_BLOCK_SIZE,
243 		.cra_module      = THIS_MODULE,
244 		.cra_ctxsize     = sizeof(struct nx_crypto_ctx),
245 		.cra_init        = nx_crypto_ctx_sha_init,
246 		.cra_exit        = nx_crypto_ctx_exit,
247 	}
248 };
249