1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * CRC vpmsum tester
4 * Copyright 2017 Daniel Axtens, IBM Corporation.
5 */
6
7 #include <linux/crc-t10dif.h>
8 #include <linux/crc32.h>
9 #include <crypto/internal/hash.h>
10 #include <linux/init.h>
11 #include <linux/module.h>
12 #include <linux/random.h>
13 #include <linux/string.h>
14 #include <linux/kernel.h>
15 #include <linux/cpufeature.h>
16 #include <asm/switch_to.h>
17
18 static unsigned long iterations = 10000;
19
20 #define MAX_CRC_LENGTH 65535
21
22
crc_test_init(void)23 static int __init crc_test_init(void)
24 {
25 u16 crc16 = 0, verify16 = 0;
26 __le32 verify32le = 0;
27 unsigned char *data;
28 u32 verify32 = 0;
29 unsigned long i;
30 __le32 crc32;
31 int ret;
32
33 struct crypto_shash *crct10dif_tfm;
34 struct crypto_shash *crc32c_tfm;
35
36 if (!cpu_has_feature(CPU_FTR_ARCH_207S))
37 return -ENODEV;
38
39 data = kmalloc(MAX_CRC_LENGTH, GFP_KERNEL);
40 if (!data)
41 return -ENOMEM;
42
43 crct10dif_tfm = crypto_alloc_shash("crct10dif", 0, 0);
44
45 if (IS_ERR(crct10dif_tfm)) {
46 pr_err("Error allocating crc-t10dif\n");
47 goto free_buf;
48 }
49
50 crc32c_tfm = crypto_alloc_shash("crc32c", 0, 0);
51
52 if (IS_ERR(crc32c_tfm)) {
53 pr_err("Error allocating crc32c\n");
54 goto free_16;
55 }
56
57 do {
58 SHASH_DESC_ON_STACK(crct10dif_shash, crct10dif_tfm);
59 SHASH_DESC_ON_STACK(crc32c_shash, crc32c_tfm);
60
61 crct10dif_shash->tfm = crct10dif_tfm;
62 ret = crypto_shash_init(crct10dif_shash);
63
64 if (ret) {
65 pr_err("Error initing crc-t10dif\n");
66 goto free_32;
67 }
68
69
70 crc32c_shash->tfm = crc32c_tfm;
71 ret = crypto_shash_init(crc32c_shash);
72
73 if (ret) {
74 pr_err("Error initing crc32c\n");
75 goto free_32;
76 }
77
78 pr_info("crc-vpmsum_test begins, %lu iterations\n", iterations);
79 for (i=0; i<iterations; i++) {
80 size_t offset = prandom_u32_max(16);
81 size_t len = prandom_u32_max(MAX_CRC_LENGTH);
82
83 if (len <= offset)
84 continue;
85 prandom_bytes(data, len);
86 len -= offset;
87
88 crypto_shash_update(crct10dif_shash, data+offset, len);
89 crypto_shash_final(crct10dif_shash, (u8 *)(&crc16));
90 verify16 = crc_t10dif_generic(verify16, data+offset, len);
91
92
93 if (crc16 != verify16) {
94 pr_err("FAILURE in CRC16: got 0x%04x expected 0x%04x (len %lu)\n",
95 crc16, verify16, len);
96 break;
97 }
98
99 crypto_shash_update(crc32c_shash, data+offset, len);
100 crypto_shash_final(crc32c_shash, (u8 *)(&crc32));
101 verify32 = le32_to_cpu(verify32le);
102 verify32le = ~cpu_to_le32(__crc32c_le(~verify32, data+offset, len));
103 if (crc32 != verify32le) {
104 pr_err("FAILURE in CRC32: got 0x%08x expected 0x%08x (len %lu)\n",
105 crc32, verify32, len);
106 break;
107 }
108 cond_resched();
109 }
110 pr_info("crc-vpmsum_test done, completed %lu iterations\n", i);
111 } while (0);
112
113 free_32:
114 crypto_free_shash(crc32c_tfm);
115
116 free_16:
117 crypto_free_shash(crct10dif_tfm);
118
119 free_buf:
120 kfree(data);
121
122 return 0;
123 }
124
crc_test_exit(void)125 static void __exit crc_test_exit(void) {}
126
127 module_init(crc_test_init);
128 module_exit(crc_test_exit);
129 module_param(iterations, long, 0400);
130
131 MODULE_AUTHOR("Daniel Axtens <dja@axtens.net>");
132 MODULE_DESCRIPTION("Vector polynomial multiply-sum CRC tester");
133 MODULE_LICENSE("GPL");
134