1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * SHA-256 routines supporting the Power 7+ Nest Accelerators driver
4  *
5  * Copyright (C) 2011-2012 International Business Machines Inc.
6  *
7  * Author: Kent Yoder <yoder1@us.ibm.com>
8  */
9 
10 #include <crypto/internal/hash.h>
11 #include <crypto/sha2.h>
12 #include <linux/errno.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/spinlock.h>
16 #include <linux/string.h>
17 #include <linux/unaligned.h>
18 
19 #include "nx_csbcpb.h"
20 #include "nx.h"
21 
22 struct sha256_state_be {
23 	__be32 state[SHA256_DIGEST_SIZE / 4];
24 	u64 count;
25 };
26 
27 static int nx_crypto_ctx_sha256_init(struct crypto_shash *tfm)
28 {
29 	struct nx_crypto_ctx *nx_ctx = crypto_shash_ctx(tfm);
30 	int err;
31 
32 	err = nx_crypto_ctx_sha_init(tfm);
33 	if (err)
34 		return err;
35 
36 	nx_ctx_init(nx_ctx, HCOP_FC_SHA);
37 
38 	nx_ctx->ap = &nx_ctx->props[NX_PROPS_SHA256];
39 
40 	NX_CPB_SET_DIGEST_SIZE(nx_ctx->csbcpb, NX_DS_SHA256);
41 
42 	return 0;
43 }
44 
45 static int nx_sha256_init(struct shash_desc *desc)
46 {
47 	struct sha256_state_be *sctx = shash_desc_ctx(desc);
48 
49 	sctx->state[0] = __cpu_to_be32(SHA256_H0);
50 	sctx->state[1] = __cpu_to_be32(SHA256_H1);
51 	sctx->state[2] = __cpu_to_be32(SHA256_H2);
52 	sctx->state[3] = __cpu_to_be32(SHA256_H3);
53 	sctx->state[4] = __cpu_to_be32(SHA256_H4);
54 	sctx->state[5] = __cpu_to_be32(SHA256_H5);
55 	sctx->state[6] = __cpu_to_be32(SHA256_H6);
56 	sctx->state[7] = __cpu_to_be32(SHA256_H7);
57 	sctx->count = 0;
58 
59 	return 0;
60 }
61 
62 static int nx_sha256_update(struct shash_desc *desc, const u8 *data,
63 			    unsigned int len)
64 {
65 	struct nx_crypto_ctx *nx_ctx = crypto_shash_ctx(desc->tfm);
66 	struct sha256_state_be *sctx = shash_desc_ctx(desc);
67 	struct nx_csbcpb *csbcpb = (struct nx_csbcpb *)nx_ctx->csbcpb;
68 	u64 to_process, leftover, total = len;
69 	struct nx_sg *out_sg;
70 	unsigned long irq_flags;
71 	int rc = 0;
72 	int data_len;
73 	u32 max_sg_len;
74 
75 	spin_lock_irqsave(&nx_ctx->lock, irq_flags);
76 
77 	memcpy(csbcpb->cpb.sha256.message_digest, sctx->state, SHA256_DIGEST_SIZE);
78 	NX_CPB_FDM(csbcpb) |= NX_FDM_INTERMEDIATE;
79 	NX_CPB_FDM(csbcpb) |= NX_FDM_CONTINUATION;
80 
81 	max_sg_len = min_t(u64, nx_ctx->ap->sglen,
82 			nx_driver.of.max_sg_len/sizeof(struct nx_sg));
83 	max_sg_len = min_t(u64, max_sg_len,
84 			nx_ctx->ap->databytelen/NX_PAGE_SIZE);
85 
86 	data_len = SHA256_DIGEST_SIZE;
87 	out_sg = nx_build_sg_list(nx_ctx->out_sg, (u8 *)sctx->state,
88 				  &data_len, max_sg_len);
89 	nx_ctx->op.outlen = (nx_ctx->out_sg - out_sg) * sizeof(struct nx_sg);
90 
91 	if (data_len != SHA256_DIGEST_SIZE) {
92 		rc = -EINVAL;
93 		goto out;
94 	}
95 
96 	do {
97 		struct nx_sg *in_sg = nx_ctx->in_sg;
98 
99 		to_process = total & ~(SHA256_BLOCK_SIZE - 1);
100 
101 		data_len = to_process;
102 		in_sg = nx_build_sg_list(in_sg, (u8 *) data,
103 					 &data_len, max_sg_len);
104 
105 		nx_ctx->op.inlen = (nx_ctx->in_sg - in_sg) * sizeof(struct nx_sg);
106 
107 		to_process = data_len;
108 		leftover = total - to_process;
109 
110 		/*
111 		 * we've hit the nx chip previously and we're updating
112 		 * again, so copy over the partial digest.
113 		 */
114 		memcpy(csbcpb->cpb.sha256.input_partial_digest,
115 			       csbcpb->cpb.sha256.message_digest,
116 			       SHA256_DIGEST_SIZE);
117 
118 		if (!nx_ctx->op.inlen || !nx_ctx->op.outlen) {
119 			rc = -EINVAL;
120 			goto out;
121 		}
122 
123 		rc = nx_hcall_sync(nx_ctx, &nx_ctx->op, 0);
124 		if (rc)
125 			goto out;
126 
127 		atomic_inc(&(nx_ctx->stats->sha256_ops));
128 
129 		total -= to_process;
130 		data += to_process;
131 		sctx->count += to_process;
132 	} while (leftover >= SHA256_BLOCK_SIZE);
133 
134 	rc = leftover;
135 	memcpy(sctx->state, csbcpb->cpb.sha256.message_digest, SHA256_DIGEST_SIZE);
136 out:
137 	spin_unlock_irqrestore(&nx_ctx->lock, irq_flags);
138 	return rc;
139 }
140 
141 static int nx_sha256_finup(struct shash_desc *desc, const u8 *src,
142 			   unsigned int nbytes, u8 *out)
143 {
144 	struct nx_crypto_ctx *nx_ctx = crypto_shash_ctx(desc->tfm);
145 	struct sha256_state_be *sctx = shash_desc_ctx(desc);
146 	struct nx_csbcpb *csbcpb = (struct nx_csbcpb *)nx_ctx->csbcpb;
147 	struct nx_sg *in_sg, *out_sg;
148 	unsigned long irq_flags;
149 	u32 max_sg_len;
150 	int rc = 0;
151 	int len;
152 
153 	spin_lock_irqsave(&nx_ctx->lock, irq_flags);
154 
155 	max_sg_len = min_t(u64, nx_ctx->ap->sglen,
156 			nx_driver.of.max_sg_len/sizeof(struct nx_sg));
157 	max_sg_len = min_t(u64, max_sg_len,
158 			nx_ctx->ap->databytelen/NX_PAGE_SIZE);
159 
160 	/* final is represented by continuing the operation and indicating that
161 	 * this is not an intermediate operation
162 	 * copy over the partial digest */
163 	memcpy(csbcpb->cpb.sha256.input_partial_digest, sctx->state, SHA256_DIGEST_SIZE);
164 	NX_CPB_FDM(csbcpb) &= ~NX_FDM_INTERMEDIATE;
165 	NX_CPB_FDM(csbcpb) |= NX_FDM_CONTINUATION;
166 
167 	sctx->count += nbytes;
168 	csbcpb->cpb.sha256.message_bit_length = (u64) (sctx->count * 8);
169 
170 	len = nbytes;
171 	in_sg = nx_build_sg_list(nx_ctx->in_sg, (u8 *)src, &len, max_sg_len);
172 
173 	if (len != nbytes) {
174 		rc = -EINVAL;
175 		goto out;
176 	}
177 
178 	len = SHA256_DIGEST_SIZE;
179 	out_sg = nx_build_sg_list(nx_ctx->out_sg, out, &len, max_sg_len);
180 
181 	if (len != SHA256_DIGEST_SIZE) {
182 		rc = -EINVAL;
183 		goto out;
184 	}
185 
186 	nx_ctx->op.inlen = (nx_ctx->in_sg - in_sg) * sizeof(struct nx_sg);
187 	nx_ctx->op.outlen = (nx_ctx->out_sg - out_sg) * sizeof(struct nx_sg);
188 	if (!nx_ctx->op.outlen) {
189 		rc = -EINVAL;
190 		goto out;
191 	}
192 
193 	rc = nx_hcall_sync(nx_ctx, &nx_ctx->op, 0);
194 	if (rc)
195 		goto out;
196 
197 	atomic_inc(&(nx_ctx->stats->sha256_ops));
198 
199 	atomic64_add(sctx->count, &(nx_ctx->stats->sha256_bytes));
200 	memcpy(out, csbcpb->cpb.sha256.message_digest, SHA256_DIGEST_SIZE);
201 out:
202 	spin_unlock_irqrestore(&nx_ctx->lock, irq_flags);
203 	return rc;
204 }
205 
206 static int nx_sha256_export(struct shash_desc *desc, void *out)
207 {
208 	struct sha256_state_be *sctx = shash_desc_ctx(desc);
209 	union {
210 		u8 *u8;
211 		u32 *u32;
212 		u64 *u64;
213 	} p = { .u8 = out };
214 	int i;
215 
216 	for (i = 0; i < SHA256_DIGEST_SIZE / sizeof(*p.u32); i++)
217 		put_unaligned(be32_to_cpu(sctx->state[i]), p.u32++);
218 
219 	put_unaligned(sctx->count, p.u64++);
220 	return 0;
221 }
222 
223 static int nx_sha256_import(struct shash_desc *desc, const void *in)
224 {
225 	struct sha256_state_be *sctx = shash_desc_ctx(desc);
226 	union {
227 		const u8 *u8;
228 		const u32 *u32;
229 		const u64 *u64;
230 	} p = { .u8 = in };
231 	int i;
232 
233 	for (i = 0; i < SHA256_DIGEST_SIZE / sizeof(*p.u32); i++)
234 		sctx->state[i] = cpu_to_be32(get_unaligned(p.u32++));
235 
236 	sctx->count = get_unaligned(p.u64++);
237 	return 0;
238 }
239 
240 struct shash_alg nx_shash_sha256_alg = {
241 	.digestsize = SHA256_DIGEST_SIZE,
242 	.init       = nx_sha256_init,
243 	.update     = nx_sha256_update,
244 	.finup      = nx_sha256_finup,
245 	.export     = nx_sha256_export,
246 	.import     = nx_sha256_import,
247 	.init_tfm   = nx_crypto_ctx_sha256_init,
248 	.exit_tfm   = nx_crypto_ctx_shash_exit,
249 	.descsize   = sizeof(struct sha256_state_be),
250 	.statesize  = sizeof(struct sha256_state_be),
251 	.base       = {
252 		.cra_name        = "sha256",
253 		.cra_driver_name = "sha256-nx",
254 		.cra_priority    = 300,
255 		.cra_flags	 = CRYPTO_AHASH_ALG_BLOCK_ONLY,
256 		.cra_blocksize   = SHA256_BLOCK_SIZE,
257 		.cra_module      = THIS_MODULE,
258 		.cra_ctxsize     = sizeof(struct nx_crypto_ctx),
259 	}
260 };
261