summaryrefslogtreecommitdiff
path: root/drivers/crypto/caam/key_gen.c
blob: c425d4adaf2af69a85ea830a78f41238c980720d (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
/*
 * CAAM/SEC 4.x functions for handling key-generation jobs
 *
 * Copyright 2008-2011 Freescale Semiconductor, Inc.
 *
 */
#include "compat.h"
#include "jr.h"
#include "error.h"
#include "desc_constr.h"
#include "key_gen.h"

/**
 * split_key_len - Compute MDHA split key length for a given algorithm
 * @hash: Hashing algorithm selection, one of OP_ALG_ALGSEL_* - MD5, SHA1,
 *        SHA224, SHA384, SHA512.
 *
 * Return: MDHA split key length
 */
static inline u32 split_key_len(u32 hash)
{
	/* Sizes for MDHA pads (*not* keys): MD5, SHA1, 224, 256, 384, 512 */
	static const u8 mdpadlen[] = { 16, 20, 32, 32, 64, 64 };
	u32 idx;

	idx = (hash & OP_ALG_ALGSEL_SUBMASK) >> OP_ALG_ALGSEL_SHIFT;

	return (u32)(mdpadlen[idx] * 2);
}

/**
 * split_key_pad_len - Compute MDHA split key pad length for a given algorithm
 * @hash: Hashing algorithm selection, one of OP_ALG_ALGSEL_* - MD5, SHA1,
 *        SHA224, SHA384, SHA512.
 *
 * Return: MDHA split key pad length
 */
static inline u32 split_key_pad_len(u32 hash)
{
	return ALIGN(split_key_len(hash), 16);
}

void split_key_done(struct device *dev, u32 *desc, u32 err,
			   void *context)
{
	struct split_key_result *res = context;

#ifdef DEBUG
	dev_err(dev, "%s %d: err 0x%x\n", __func__, __LINE__, err);
#endif

	if (err)
		caam_jr_strstatus(dev, err);

	res->err = err;

	complete(&res->completion);
}
EXPORT_SYMBOL(split_key_done);
/*
get a split ipad/opad key

Split key generation-----------------------------------------------

[00] 0xb0810008    jobdesc: stidx=1 share=never len=8
[01] 0x04000014        key: class2->keyreg len=20
			@0xffe01000
[03] 0x84410014  operation: cls2-op sha1 hmac init dec
[04] 0x24940000     fifold: class2 msgdata-last2 len=0 imm
[05] 0xa4000001       jump: class2 local all ->1 [06]
[06] 0x64260028    fifostr: class2 mdsplit-jdk len=40
			@0xffe04000
*/
int gen_split_key(struct device *jrdev, u8 *key_out,
		  struct alginfo * const adata, const u8 *key_in, u32 keylen,
		  int max_keylen)
{
	u32 *desc;
	struct split_key_result result;
	dma_addr_t dma_addr_in, dma_addr_out;
	int ret = -ENOMEM;

	adata->keylen = split_key_len(adata->algtype & OP_ALG_ALGSEL_MASK);
	adata->keylen_pad = split_key_pad_len(adata->algtype &
					      OP_ALG_ALGSEL_MASK);

#ifdef DEBUG
	dev_err(jrdev, "split keylen %d split keylen padded %d\n",
		adata->keylen, adata->keylen_pad);
	print_hex_dump(KERN_ERR, "ctx.key@" __stringify(__LINE__)": ",
		       DUMP_PREFIX_ADDRESS, 16, 4, key_in, keylen, 1);
#endif

	if (adata->keylen_pad > max_keylen)
		return -EINVAL;

	desc = kmalloc(CAAM_CMD_SZ * 6 + CAAM_PTR_SZ * 2, GFP_KERNEL | GFP_DMA);
	if (!desc) {
		dev_err(jrdev, "unable to allocate key input memory\n");
		return ret;
	}

	dma_addr_in = dma_map_single(jrdev, (void *)key_in, keylen,
				     DMA_TO_DEVICE);
	if (dma_mapping_error(jrdev, dma_addr_in)) {
		dev_err(jrdev, "unable to map key input memory\n");
		goto out_free;
	}

	dma_addr_out = dma_map_single(jrdev, key_out, adata->keylen_pad,
				      DMA_FROM_DEVICE);
	if (dma_mapping_error(jrdev, dma_addr_out)) {
		dev_err(jrdev, "unable to map key output memory\n");
		goto out_unmap_in;
	}

	init_job_desc(desc, 0);
	append_key(desc, dma_addr_in, keylen, CLASS_2 | KEY_DEST_CLASS_REG);

	/* Sets MDHA up into an HMAC-INIT */
	append_operation(desc, (adata->algtype & OP_ALG_ALGSEL_MASK) |
			 OP_ALG_AAI_HMAC | OP_TYPE_CLASS2_ALG | OP_ALG_DECRYPT |
			 OP_ALG_AS_INIT);

	/*
	 * do a FIFO_LOAD of zero, this will trigger the internal key expansion
	 * into both pads inside MDHA
	 */
	append_fifo_load_as_imm(desc, NULL, 0, LDST_CLASS_2_CCB |
				FIFOLD_TYPE_MSG | FIFOLD_TYPE_LAST2);

	/*
	 * FIFO_STORE with the explicit split-key content store
	 * (0x26 output type)
	 */
	append_fifo_store(desc, dma_addr_out, adata->keylen,
			  LDST_CLASS_2_CCB | FIFOST_TYPE_SPLIT_KEK);

#ifdef DEBUG
	print_hex_dump(KERN_ERR, "ctx.key@"__stringify(__LINE__)": ",
		       DUMP_PREFIX_ADDRESS, 16, 4, key_in, keylen, 1);
	print_hex_dump(KERN_ERR, "jobdesc@"__stringify(__LINE__)": ",
		       DUMP_PREFIX_ADDRESS, 16, 4, desc, desc_bytes(desc), 1);
#endif

	result.err = 0;
	init_completion(&result.completion);

	ret = caam_jr_enqueue(jrdev, desc, split_key_done, &result);
	if (!ret) {
		/* in progress */
		wait_for_completion(&result.completion);
		ret = result.err;
#ifdef DEBUG
		print_hex_dump(KERN_ERR, "ctx.key@"__stringify(__LINE__)": ",
			       DUMP_PREFIX_ADDRESS, 16, 4, key_out,
			       adata->keylen_pad, 1);
#endif
	}

	dma_unmap_single(jrdev, dma_addr_out, adata->keylen_pad,
			 DMA_FROM_DEVICE);
out_unmap_in:
	dma_unmap_single(jrdev, dma_addr_in, keylen, DMA_TO_DEVICE);
out_free:
	kfree(desc);
	return ret;
}
EXPORT_SYMBOL(gen_split_key);