xref: /openbmc/linux/drivers/crypto/caam/key_gen.c (revision 5bd8e16d)
1 /*
2  * CAAM/SEC 4.x functions for handling key-generation jobs
3  *
4  * Copyright 2008-2011 Freescale Semiconductor, Inc.
5  *
6  */
7 #include "compat.h"
8 #include "jr.h"
9 #include "error.h"
10 #include "desc_constr.h"
11 #include "key_gen.h"
12 
13 void split_key_done(struct device *dev, u32 *desc, u32 err,
14 			   void *context)
15 {
16 	struct split_key_result *res = context;
17 
18 #ifdef DEBUG
19 	dev_err(dev, "%s %d: err 0x%x\n", __func__, __LINE__, err);
20 #endif
21 
22 	if (err) {
23 		char tmp[CAAM_ERROR_STR_MAX];
24 
25 		dev_err(dev, "%08x: %s\n", err, caam_jr_strstatus(tmp, err));
26 	}
27 
28 	res->err = err;
29 
30 	complete(&res->completion);
31 }
32 EXPORT_SYMBOL(split_key_done);
33 /*
34 get a split ipad/opad key
35 
36 Split key generation-----------------------------------------------
37 
38 [00] 0xb0810008    jobdesc: stidx=1 share=never len=8
39 [01] 0x04000014        key: class2->keyreg len=20
40 			@0xffe01000
41 [03] 0x84410014  operation: cls2-op sha1 hmac init dec
42 [04] 0x24940000     fifold: class2 msgdata-last2 len=0 imm
43 [05] 0xa4000001       jump: class2 local all ->1 [06]
44 [06] 0x64260028    fifostr: class2 mdsplit-jdk len=40
45 			@0xffe04000
46 */
47 int gen_split_key(struct device *jrdev, u8 *key_out, int split_key_len,
48 		  int split_key_pad_len, const u8 *key_in, u32 keylen,
49 		  u32 alg_op)
50 {
51 	u32 *desc;
52 	struct split_key_result result;
53 	dma_addr_t dma_addr_in, dma_addr_out;
54 	int ret = 0;
55 
56 	desc = kmalloc(CAAM_CMD_SZ * 6 + CAAM_PTR_SZ * 2, GFP_KERNEL | GFP_DMA);
57 	if (!desc) {
58 		dev_err(jrdev, "unable to allocate key input memory\n");
59 		return -ENOMEM;
60 	}
61 
62 	init_job_desc(desc, 0);
63 
64 	dma_addr_in = dma_map_single(jrdev, (void *)key_in, keylen,
65 				     DMA_TO_DEVICE);
66 	if (dma_mapping_error(jrdev, dma_addr_in)) {
67 		dev_err(jrdev, "unable to map key input memory\n");
68 		kfree(desc);
69 		return -ENOMEM;
70 	}
71 	append_key(desc, dma_addr_in, keylen, CLASS_2 | KEY_DEST_CLASS_REG);
72 
73 	/* Sets MDHA up into an HMAC-INIT */
74 	append_operation(desc, alg_op | OP_ALG_DECRYPT | OP_ALG_AS_INIT);
75 
76 	/*
77 	 * do a FIFO_LOAD of zero, this will trigger the internal key expansion
78 	 * into both pads inside MDHA
79 	 */
80 	append_fifo_load_as_imm(desc, NULL, 0, LDST_CLASS_2_CCB |
81 				FIFOLD_TYPE_MSG | FIFOLD_TYPE_LAST2);
82 
83 	/*
84 	 * FIFO_STORE with the explicit split-key content store
85 	 * (0x26 output type)
86 	 */
87 	dma_addr_out = dma_map_single(jrdev, key_out, split_key_pad_len,
88 				      DMA_FROM_DEVICE);
89 	if (dma_mapping_error(jrdev, dma_addr_out)) {
90 		dev_err(jrdev, "unable to map key output memory\n");
91 		kfree(desc);
92 		return -ENOMEM;
93 	}
94 	append_fifo_store(desc, dma_addr_out, split_key_len,
95 			  LDST_CLASS_2_CCB | FIFOST_TYPE_SPLIT_KEK);
96 
97 #ifdef DEBUG
98 	print_hex_dump(KERN_ERR, "ctx.key@"__stringify(__LINE__)": ",
99 		       DUMP_PREFIX_ADDRESS, 16, 4, key_in, keylen, 1);
100 	print_hex_dump(KERN_ERR, "jobdesc@"__stringify(__LINE__)": ",
101 		       DUMP_PREFIX_ADDRESS, 16, 4, desc, desc_bytes(desc), 1);
102 #endif
103 
104 	result.err = 0;
105 	init_completion(&result.completion);
106 
107 	ret = caam_jr_enqueue(jrdev, desc, split_key_done, &result);
108 	if (!ret) {
109 		/* in progress */
110 		wait_for_completion_interruptible(&result.completion);
111 		ret = result.err;
112 #ifdef DEBUG
113 		print_hex_dump(KERN_ERR, "ctx.key@"__stringify(__LINE__)": ",
114 			       DUMP_PREFIX_ADDRESS, 16, 4, key_out,
115 			       split_key_pad_len, 1);
116 #endif
117 	}
118 
119 	dma_unmap_single(jrdev, dma_addr_out, split_key_pad_len,
120 			 DMA_FROM_DEVICE);
121 	dma_unmap_single(jrdev, dma_addr_in, keylen, DMA_TO_DEVICE);
122 
123 	kfree(desc);
124 
125 	return ret;
126 }
127 EXPORT_SYMBOL(gen_split_key);
128