write in 30M

hc

2024-02-20 ea08eeccae9297f7aabd2ef7f0c2517ac4549acc

 kernel/crypto/aes_ti.c
..
..
@@ -1,281 +1,26 @@
1
+// SPDX-License-Identifier: GPL-2.0-only
1
2
 /*
2
3
  * Scalar fixed time AES core transform
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4
  *
4
5
  * Copyright (C) 2017 Linaro Ltd <ard.biesheuvel@linaro.org>
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- *
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- * This program is free software; you can redistribute it and/or modify
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- * it under the terms of the GNU General Public License version 2 as
8
- * published by the Free Software Foundation.
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  */
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11
8
 #include <crypto/aes.h>
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9
 #include <linux/crypto.h>
13
10
 #include <linux/module.h>
14
-#include <asm/unaligned.h>
15
-
16
-/*
17
- * Emit the sbox as volatile const to prevent the compiler from doing
18
- * constant folding on sbox references involving fixed indexes.
19
- */
20
-static volatile const u8 __cacheline_aligned __aesti_sbox[] = {
21
-	0x63, 0x7c, 0x77, 0x7b, 0xf2, 0x6b, 0x6f, 0xc5,
22
-	0x30, 0x01, 0x67, 0x2b, 0xfe, 0xd7, 0xab, 0x76,
23
-	0xca, 0x82, 0xc9, 0x7d, 0xfa, 0x59, 0x47, 0xf0,
24
-	0xad, 0xd4, 0xa2, 0xaf, 0x9c, 0xa4, 0x72, 0xc0,
25
-	0xb7, 0xfd, 0x93, 0x26, 0x36, 0x3f, 0xf7, 0xcc,
26
-	0x34, 0xa5, 0xe5, 0xf1, 0x71, 0xd8, 0x31, 0x15,
27
-	0x04, 0xc7, 0x23, 0xc3, 0x18, 0x96, 0x05, 0x9a,
28
-	0x07, 0x12, 0x80, 0xe2, 0xeb, 0x27, 0xb2, 0x75,
29
-	0x09, 0x83, 0x2c, 0x1a, 0x1b, 0x6e, 0x5a, 0xa0,
30
-	0x52, 0x3b, 0xd6, 0xb3, 0x29, 0xe3, 0x2f, 0x84,
31
-	0x53, 0xd1, 0x00, 0xed, 0x20, 0xfc, 0xb1, 0x5b,
32
-	0x6a, 0xcb, 0xbe, 0x39, 0x4a, 0x4c, 0x58, 0xcf,
33
-	0xd0, 0xef, 0xaa, 0xfb, 0x43, 0x4d, 0x33, 0x85,
34
-	0x45, 0xf9, 0x02, 0x7f, 0x50, 0x3c, 0x9f, 0xa8,
35
-	0x51, 0xa3, 0x40, 0x8f, 0x92, 0x9d, 0x38, 0xf5,
36
-	0xbc, 0xb6, 0xda, 0x21, 0x10, 0xff, 0xf3, 0xd2,
37
-	0xcd, 0x0c, 0x13, 0xec, 0x5f, 0x97, 0x44, 0x17,
38
-	0xc4, 0xa7, 0x7e, 0x3d, 0x64, 0x5d, 0x19, 0x73,
39
-	0x60, 0x81, 0x4f, 0xdc, 0x22, 0x2a, 0x90, 0x88,
40
-	0x46, 0xee, 0xb8, 0x14, 0xde, 0x5e, 0x0b, 0xdb,
41
-	0xe0, 0x32, 0x3a, 0x0a, 0x49, 0x06, 0x24, 0x5c,
42
-	0xc2, 0xd3, 0xac, 0x62, 0x91, 0x95, 0xe4, 0x79,
43
-	0xe7, 0xc8, 0x37, 0x6d, 0x8d, 0xd5, 0x4e, 0xa9,
44
-	0x6c, 0x56, 0xf4, 0xea, 0x65, 0x7a, 0xae, 0x08,
45
-	0xba, 0x78, 0x25, 0x2e, 0x1c, 0xa6, 0xb4, 0xc6,
46
-	0xe8, 0xdd, 0x74, 0x1f, 0x4b, 0xbd, 0x8b, 0x8a,
47
-	0x70, 0x3e, 0xb5, 0x66, 0x48, 0x03, 0xf6, 0x0e,
48
-	0x61, 0x35, 0x57, 0xb9, 0x86, 0xc1, 0x1d, 0x9e,
49
-	0xe1, 0xf8, 0x98, 0x11, 0x69, 0xd9, 0x8e, 0x94,
50
-	0x9b, 0x1e, 0x87, 0xe9, 0xce, 0x55, 0x28, 0xdf,
51
-	0x8c, 0xa1, 0x89, 0x0d, 0xbf, 0xe6, 0x42, 0x68,
52
-	0x41, 0x99, 0x2d, 0x0f, 0xb0, 0x54, 0xbb, 0x16,
53
-};
54
-
55
-static volatile const u8 __cacheline_aligned __aesti_inv_sbox[] = {
56
-	0x52, 0x09, 0x6a, 0xd5, 0x30, 0x36, 0xa5, 0x38,
57
-	0xbf, 0x40, 0xa3, 0x9e, 0x81, 0xf3, 0xd7, 0xfb,
58
-	0x7c, 0xe3, 0x39, 0x82, 0x9b, 0x2f, 0xff, 0x87,
59
-	0x34, 0x8e, 0x43, 0x44, 0xc4, 0xde, 0xe9, 0xcb,
60
-	0x54, 0x7b, 0x94, 0x32, 0xa6, 0xc2, 0x23, 0x3d,
61
-	0xee, 0x4c, 0x95, 0x0b, 0x42, 0xfa, 0xc3, 0x4e,
62
-	0x08, 0x2e, 0xa1, 0x66, 0x28, 0xd9, 0x24, 0xb2,
63
-	0x76, 0x5b, 0xa2, 0x49, 0x6d, 0x8b, 0xd1, 0x25,
64
-	0x72, 0xf8, 0xf6, 0x64, 0x86, 0x68, 0x98, 0x16,
65
-	0xd4, 0xa4, 0x5c, 0xcc, 0x5d, 0x65, 0xb6, 0x92,
66
-	0x6c, 0x70, 0x48, 0x50, 0xfd, 0xed, 0xb9, 0xda,
67
-	0x5e, 0x15, 0x46, 0x57, 0xa7, 0x8d, 0x9d, 0x84,
68
-	0x90, 0xd8, 0xab, 0x00, 0x8c, 0xbc, 0xd3, 0x0a,
69
-	0xf7, 0xe4, 0x58, 0x05, 0xb8, 0xb3, 0x45, 0x06,
70
-	0xd0, 0x2c, 0x1e, 0x8f, 0xca, 0x3f, 0x0f, 0x02,
71
-	0xc1, 0xaf, 0xbd, 0x03, 0x01, 0x13, 0x8a, 0x6b,
72
-	0x3a, 0x91, 0x11, 0x41, 0x4f, 0x67, 0xdc, 0xea,
73
-	0x97, 0xf2, 0xcf, 0xce, 0xf0, 0xb4, 0xe6, 0x73,
74
-	0x96, 0xac, 0x74, 0x22, 0xe7, 0xad, 0x35, 0x85,
75
-	0xe2, 0xf9, 0x37, 0xe8, 0x1c, 0x75, 0xdf, 0x6e,
76
-	0x47, 0xf1, 0x1a, 0x71, 0x1d, 0x29, 0xc5, 0x89,
77
-	0x6f, 0xb7, 0x62, 0x0e, 0xaa, 0x18, 0xbe, 0x1b,
78
-	0xfc, 0x56, 0x3e, 0x4b, 0xc6, 0xd2, 0x79, 0x20,
79
-	0x9a, 0xdb, 0xc0, 0xfe, 0x78, 0xcd, 0x5a, 0xf4,
80
-	0x1f, 0xdd, 0xa8, 0x33, 0x88, 0x07, 0xc7, 0x31,
81
-	0xb1, 0x12, 0x10, 0x59, 0x27, 0x80, 0xec, 0x5f,
82
-	0x60, 0x51, 0x7f, 0xa9, 0x19, 0xb5, 0x4a, 0x0d,
83
-	0x2d, 0xe5, 0x7a, 0x9f, 0x93, 0xc9, 0x9c, 0xef,
84
-	0xa0, 0xe0, 0x3b, 0x4d, 0xae, 0x2a, 0xf5, 0xb0,
85
-	0xc8, 0xeb, 0xbb, 0x3c, 0x83, 0x53, 0x99, 0x61,
86
-	0x17, 0x2b, 0x04, 0x7e, 0xba, 0x77, 0xd6, 0x26,
87
-	0xe1, 0x69, 0x14, 0x63, 0x55, 0x21, 0x0c, 0x7d,
88
-};
89
-
90
-static u32 mul_by_x(u32 w)
91
-{
92
-	u32 x = w & 0x7f7f7f7f;
93
-	u32 y = w & 0x80808080;
94
-
95
-	/* multiply by polynomial 'x' (0b10) in GF(2^8) */
96
-	return (x << 1) ^ (y >> 7) * 0x1b;
97
-}
98
-
99
-static u32 mul_by_x2(u32 w)
100
-{
101
-	u32 x = w & 0x3f3f3f3f;
102
-	u32 y = w & 0x80808080;
103
-	u32 z = w & 0x40404040;
104
-
105
-	/* multiply by polynomial 'x^2' (0b100) in GF(2^8) */
106
-	return (x << 2) ^ (y >> 7) * 0x36 ^ (z >> 6) * 0x1b;
107
-}
108
-
109
-static u32 mix_columns(u32 x)
110
-{
111
-	/*
112
-	 * Perform the following matrix multiplication in GF(2^8)
113
-	 *
114
-	 * | 0x2 0x3 0x1 0x1 |   | x[0] |
115
-	 * | 0x1 0x2 0x3 0x1 |   | x[1] |
116
-	 * | 0x1 0x1 0x2 0x3 | x | x[2] |
117
-	 * | 0x3 0x1 0x1 0x2 |   | x[3] |
118
-	 */
119
-	u32 y = mul_by_x(x) ^ ror32(x, 16);
120
-
121
-	return y ^ ror32(x ^ y, 8);
122
-}
123
-
124
-static u32 inv_mix_columns(u32 x)
125
-{
126
-	/*
127
-	 * Perform the following matrix multiplication in GF(2^8)
128
-	 *
129
-	 * | 0xe 0xb 0xd 0x9 |   | x[0] |
130
-	 * | 0x9 0xe 0xb 0xd |   | x[1] |
131
-	 * | 0xd 0x9 0xe 0xb | x | x[2] |
132
-	 * | 0xb 0xd 0x9 0xe |   | x[3] |
133
-	 *
134
-	 * which can conveniently be reduced to
135
-	 *
136
-	 * | 0x2 0x3 0x1 0x1 |   | 0x5 0x0 0x4 0x0 |   | x[0] |
137
-	 * | 0x1 0x2 0x3 0x1 |   | 0x0 0x5 0x0 0x4 |   | x[1] |
138
-	 * | 0x1 0x1 0x2 0x3 | x | 0x4 0x0 0x5 0x0 | x | x[2] |
139
-	 * | 0x3 0x1 0x1 0x2 |   | 0x0 0x4 0x0 0x5 |   | x[3] |
140
-	 */
141
-	u32 y = mul_by_x2(x);
142
-
143
-	return mix_columns(x ^ y ^ ror32(y, 16));
144
-}
145
-
146
-static __always_inline u32 subshift(u32 in[], int pos)
147
-{
148
-	return (__aesti_sbox[in[pos] & 0xff]) ^
149
-	       (__aesti_sbox[(in[(pos + 1) % 4] >>  8) & 0xff] <<  8) ^
150
-	       (__aesti_sbox[(in[(pos + 2) % 4] >> 16) & 0xff] << 16) ^
151
-	       (__aesti_sbox[(in[(pos + 3) % 4] >> 24) & 0xff] << 24);
152
-}
153
-
154
-static __always_inline u32 inv_subshift(u32 in[], int pos)
155
-{
156
-	return (__aesti_inv_sbox[in[pos] & 0xff]) ^
157
-	       (__aesti_inv_sbox[(in[(pos + 3) % 4] >>  8) & 0xff] <<  8) ^
158
-	       (__aesti_inv_sbox[(in[(pos + 2) % 4] >> 16) & 0xff] << 16) ^
159
-	       (__aesti_inv_sbox[(in[(pos + 1) % 4] >> 24) & 0xff] << 24);
160
-}
161
-
162
-static u32 subw(u32 in)
163
-{
164
-	return (__aesti_sbox[in & 0xff]) ^
165
-	       (__aesti_sbox[(in >>  8) & 0xff] <<  8) ^
166
-	       (__aesti_sbox[(in >> 16) & 0xff] << 16) ^
167
-	       (__aesti_sbox[(in >> 24) & 0xff] << 24);
168
-}
169
-
170
-static int aesti_expand_key(struct crypto_aes_ctx *ctx, const u8 *in_key,
171
-			    unsigned int key_len)
172
-{
173
-	u32 kwords = key_len / sizeof(u32);
174
-	u32 rc, i, j;
175
-
176
-	if (key_len != AES_KEYSIZE_128 &&
177
-	    key_len != AES_KEYSIZE_192 &&
178
-	    key_len != AES_KEYSIZE_256)
179
-		return -EINVAL;
180
-
181
-	ctx->key_length = key_len;
182
-
183
-	for (i = 0; i < kwords; i++)
184
-		ctx->key_enc[i] = get_unaligned_le32(in_key + i * sizeof(u32));
185
-
186
-	for (i = 0, rc = 1; i < 10; i++, rc = mul_by_x(rc)) {
187
-		u32 *rki = ctx->key_enc + (i * kwords);
188
-		u32 *rko = rki + kwords;
189
-
190
-		rko[0] = ror32(subw(rki[kwords - 1]), 8) ^ rc ^ rki[0];
191
-		rko[1] = rko[0] ^ rki[1];
192
-		rko[2] = rko[1] ^ rki[2];
193
-		rko[3] = rko[2] ^ rki[3];
194
-
195
-		if (key_len == 24) {
196
-			if (i >= 7)
197
-				break;
198
-			rko[4] = rko[3] ^ rki[4];
199
-			rko[5] = rko[4] ^ rki[5];
200
-		} else if (key_len == 32) {
201
-			if (i >= 6)
202
-				break;
203
-			rko[4] = subw(rko[3]) ^ rki[4];
204
-			rko[5] = rko[4] ^ rki[5];
205
-			rko[6] = rko[5] ^ rki[6];
206
-			rko[7] = rko[6] ^ rki[7];
207
-		}
208
-	}
209
-
210
-	/*
211
-	 * Generate the decryption keys for the Equivalent Inverse Cipher.
212
-	 * This involves reversing the order of the round keys, and applying
213
-	 * the Inverse Mix Columns transformation to all but the first and
214
-	 * the last one.
215
-	 */
216
-	ctx->key_dec[0] = ctx->key_enc[key_len + 24];
217
-	ctx->key_dec[1] = ctx->key_enc[key_len + 25];
218
-	ctx->key_dec[2] = ctx->key_enc[key_len + 26];
219
-	ctx->key_dec[3] = ctx->key_enc[key_len + 27];
220
-
221
-	for (i = 4, j = key_len + 20; j > 0; i += 4, j -= 4) {
222
-		ctx->key_dec[i]     = inv_mix_columns(ctx->key_enc[j]);
223
-		ctx->key_dec[i + 1] = inv_mix_columns(ctx->key_enc[j + 1]);
224
-		ctx->key_dec[i + 2] = inv_mix_columns(ctx->key_enc[j + 2]);
225
-		ctx->key_dec[i + 3] = inv_mix_columns(ctx->key_enc[j + 3]);
226
-	}
227
-
228
-	ctx->key_dec[i]     = ctx->key_enc[0];
229
-	ctx->key_dec[i + 1] = ctx->key_enc[1];
230
-	ctx->key_dec[i + 2] = ctx->key_enc[2];
231
-	ctx->key_dec[i + 3] = ctx->key_enc[3];
232
-
233
-	return 0;
234
-}
235
11
 
236
12
 static int aesti_set_key(struct crypto_tfm *tfm, const u8 *in_key,
237
13
 			 unsigned int key_len)
238
14
 {
239
15
 	struct crypto_aes_ctx *ctx = crypto_tfm_ctx(tfm);
240
-	int err;
241
16
 
242
-	err = aesti_expand_key(ctx, in_key, key_len);
243
-	if (err)
244
-		return err;
245
-
246
-	/*
247
-	 * In order to force the compiler to emit data independent Sbox lookups
248
-	 * at the start of each block, xor the first round key with values at
249
-	 * fixed indexes in the Sbox. This will need to be repeated each time
250
-	 * the key is used, which will pull the entire Sbox into the D-cache
251
-	 * before any data dependent Sbox lookups are performed.
252
-	 */
253
-	ctx->key_enc[0] ^= __aesti_sbox[ 0] ^ __aesti_sbox[128];
254
-	ctx->key_enc[1] ^= __aesti_sbox[32] ^ __aesti_sbox[160];
255
-	ctx->key_enc[2] ^= __aesti_sbox[64] ^ __aesti_sbox[192];
256
-	ctx->key_enc[3] ^= __aesti_sbox[96] ^ __aesti_sbox[224];
257
-
258
-	ctx->key_dec[0] ^= __aesti_inv_sbox[ 0] ^ __aesti_inv_sbox[128];
259
-	ctx->key_dec[1] ^= __aesti_inv_sbox[32] ^ __aesti_inv_sbox[160];
260
-	ctx->key_dec[2] ^= __aesti_inv_sbox[64] ^ __aesti_inv_sbox[192];
261
-	ctx->key_dec[3] ^= __aesti_inv_sbox[96] ^ __aesti_inv_sbox[224];
262
-
263
-	return 0;
17
+	return aes_expandkey(ctx, in_key, key_len);
264
18
 }
265
19
 
266
20
 static void aesti_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
267
21
 {
268
22
 	const struct crypto_aes_ctx *ctx = crypto_tfm_ctx(tfm);
269
-	const u32 *rkp = ctx->key_enc + 4;
270
-	int rounds = 6 + ctx->key_length / 4;
271
-	u32 st0[4], st1[4];
272
23
 	unsigned long flags;
273
-	int round;
274
-
275
-	st0[0] = ctx->key_enc[0] ^ get_unaligned_le32(in);
276
-	st0[1] = ctx->key_enc[1] ^ get_unaligned_le32(in + 4);
277
-	st0[2] = ctx->key_enc[2] ^ get_unaligned_le32(in + 8);
278
-	st0[3] = ctx->key_enc[3] ^ get_unaligned_le32(in + 12);
279
24
 
280
25
 	/*
281
26
 	 * Temporarily disable interrupts to avoid races where cachelines are
..
..
@@ -283,30 +28,7 @@
283
28
 	 */
284
29
 	local_irq_save(flags);
285
30
 
286
-	st0[0] ^= __aesti_sbox[ 0] ^ __aesti_sbox[128];
287
-	st0[1] ^= __aesti_sbox[32] ^ __aesti_sbox[160];
288
-	st0[2] ^= __aesti_sbox[64] ^ __aesti_sbox[192];
289
-	st0[3] ^= __aesti_sbox[96] ^ __aesti_sbox[224];
290
-
291
-	for (round = 0;; round += 2, rkp += 8) {
292
-		st1[0] = mix_columns(subshift(st0, 0)) ^ rkp[0];
293
-		st1[1] = mix_columns(subshift(st0, 1)) ^ rkp[1];
294
-		st1[2] = mix_columns(subshift(st0, 2)) ^ rkp[2];
295
-		st1[3] = mix_columns(subshift(st0, 3)) ^ rkp[3];
296
-
297
-		if (round == rounds - 2)
298
-			break;
299
-
300
-		st0[0] = mix_columns(subshift(st1, 0)) ^ rkp[4];
301
-		st0[1] = mix_columns(subshift(st1, 1)) ^ rkp[5];
302
-		st0[2] = mix_columns(subshift(st1, 2)) ^ rkp[6];
303
-		st0[3] = mix_columns(subshift(st1, 3)) ^ rkp[7];
304
-	}
305
-
306
-	put_unaligned_le32(subshift(st1, 0) ^ rkp[4], out);
307
-	put_unaligned_le32(subshift(st1, 1) ^ rkp[5], out + 4);
308
-	put_unaligned_le32(subshift(st1, 2) ^ rkp[6], out + 8);
309
-	put_unaligned_le32(subshift(st1, 3) ^ rkp[7], out + 12);
31
+	aes_encrypt(ctx, out, in);
310
32
 
311
33
 	local_irq_restore(flags);
312
34
 }
..
..
@@ -314,16 +36,7 @@
314
36
 static void aesti_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
315
37
 {
316
38
 	const struct crypto_aes_ctx *ctx = crypto_tfm_ctx(tfm);
317
-	const u32 *rkp = ctx->key_dec + 4;
318
-	int rounds = 6 + ctx->key_length / 4;
319
-	u32 st0[4], st1[4];
320
39
 	unsigned long flags;
321
-	int round;
322
-
323
-	st0[0] = ctx->key_dec[0] ^ get_unaligned_le32(in);
324
-	st0[1] = ctx->key_dec[1] ^ get_unaligned_le32(in + 4);
325
-	st0[2] = ctx->key_dec[2] ^ get_unaligned_le32(in + 8);
326
-	st0[3] = ctx->key_dec[3] ^ get_unaligned_le32(in + 12);
327
40
 
328
41
 	/*
329
42
 	 * Temporarily disable interrupts to avoid races where cachelines are
..
..
@@ -331,30 +44,7 @@
331
44
 	 */
332
45
 	local_irq_save(flags);
333
46
 
334
-	st0[0] ^= __aesti_inv_sbox[ 0] ^ __aesti_inv_sbox[128];
335
-	st0[1] ^= __aesti_inv_sbox[32] ^ __aesti_inv_sbox[160];
336
-	st0[2] ^= __aesti_inv_sbox[64] ^ __aesti_inv_sbox[192];
337
-	st0[3] ^= __aesti_inv_sbox[96] ^ __aesti_inv_sbox[224];
338
-
339
-	for (round = 0;; round += 2, rkp += 8) {
340
-		st1[0] = inv_mix_columns(inv_subshift(st0, 0)) ^ rkp[0];
341
-		st1[1] = inv_mix_columns(inv_subshift(st0, 1)) ^ rkp[1];
342
-		st1[2] = inv_mix_columns(inv_subshift(st0, 2)) ^ rkp[2];
343
-		st1[3] = inv_mix_columns(inv_subshift(st0, 3)) ^ rkp[3];
344
-
345
-		if (round == rounds - 2)
346
-			break;
347
-
348
-		st0[0] = inv_mix_columns(inv_subshift(st1, 0)) ^ rkp[4];
349
-		st0[1] = inv_mix_columns(inv_subshift(st1, 1)) ^ rkp[5];
350
-		st0[2] = inv_mix_columns(inv_subshift(st1, 2)) ^ rkp[6];
351
-		st0[3] = inv_mix_columns(inv_subshift(st1, 3)) ^ rkp[7];
352
-	}
353
-
354
-	put_unaligned_le32(inv_subshift(st1, 0) ^ rkp[4], out);
355
-	put_unaligned_le32(inv_subshift(st1, 1) ^ rkp[5], out + 4);
356
-	put_unaligned_le32(inv_subshift(st1, 2) ^ rkp[6], out + 8);
357
-	put_unaligned_le32(inv_subshift(st1, 3) ^ rkp[7], out + 12);
47
+	aes_decrypt(ctx, out, in);
358
48
 
359
49
 	local_irq_restore(flags);
360
50
 }