1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2015 Pengutronix, Steffen Trumtrar <kernel@pengutronix.de>
4 * Copyright (C) 2021 Pengutronix, Ahmad Fatoum <kernel@pengutronix.de>
5 * Copyright 2024 NXP
6 */
7
8 #define pr_fmt(fmt) "caam blob_gen: " fmt
9
10 #include <linux/bitfield.h>
11 #include <linux/device.h>
12 #include <soc/fsl/caam-blob.h>
13
14 #include "compat.h"
15 #include "desc_constr.h"
16 #include "desc.h"
17 #include "error.h"
18 #include "intern.h"
19 #include "jr.h"
20 #include "regs.h"
21
22 #define CAAM_BLOB_DESC_BYTES_MAX \
23 /* Command to initialize & stating length of descriptor */ \
24 (CAAM_CMD_SZ + \
25 /* Command to append the key-modifier + key-modifier data */ \
26 CAAM_CMD_SZ + CAAM_BLOB_KEYMOD_LENGTH + \
27 /* Command to include input key + pointer to the input key */ \
28 CAAM_CMD_SZ + CAAM_PTR_SZ_MAX + \
29 /* Command to include output key + pointer to the output key */ \
30 CAAM_CMD_SZ + CAAM_PTR_SZ_MAX + \
31 /* Command describing the operation to perform */ \
32 CAAM_CMD_SZ)
33
34 struct caam_blob_priv {
35 struct device jrdev;
36 };
37
38 struct caam_blob_job_result {
39 int err;
40 struct completion completion;
41 };
42
caam_blob_job_done(struct device * dev,u32 * desc,u32 err,void * context)43 static void caam_blob_job_done(struct device *dev, u32 *desc, u32 err, void *context)
44 {
45 struct caam_blob_job_result *res = context;
46 int ecode = 0;
47
48 dev_dbg(dev, "%s %d: err 0x%x\n", __func__, __LINE__, err);
49
50 if (err)
51 ecode = caam_jr_strstatus(dev, err);
52
53 res->err = ecode;
54
55 /*
56 * Upon completion, desc points to a buffer containing a CAAM job
57 * descriptor which encapsulates data into an externally-storable
58 * blob.
59 */
60 complete(&res->completion);
61 }
62
caam_process_blob(struct caam_blob_priv * priv,struct caam_blob_info * info,bool encap)63 int caam_process_blob(struct caam_blob_priv *priv,
64 struct caam_blob_info *info, bool encap)
65 {
66 const struct caam_drv_private *ctrlpriv;
67 struct caam_blob_job_result testres;
68 struct device *jrdev = &priv->jrdev;
69 dma_addr_t dma_in, dma_out;
70 int op = OP_PCLID_BLOB;
71 size_t output_len;
72 u32 *desc;
73 u32 moo;
74 int ret;
75
76 if (info->key_mod_len > CAAM_BLOB_KEYMOD_LENGTH)
77 return -EINVAL;
78
79 if (encap) {
80 op |= OP_TYPE_ENCAP_PROTOCOL;
81 output_len = info->input_len + CAAM_BLOB_OVERHEAD;
82 } else {
83 op |= OP_TYPE_DECAP_PROTOCOL;
84 output_len = info->input_len - CAAM_BLOB_OVERHEAD;
85 }
86
87 desc = kzalloc(CAAM_BLOB_DESC_BYTES_MAX, GFP_KERNEL);
88 if (!desc)
89 return -ENOMEM;
90
91 dma_in = dma_map_single(jrdev, info->input, info->input_len,
92 DMA_TO_DEVICE);
93 if (dma_mapping_error(jrdev, dma_in)) {
94 dev_err(jrdev, "unable to map input DMA buffer\n");
95 ret = -ENOMEM;
96 goto out_free;
97 }
98
99 dma_out = dma_map_single(jrdev, info->output, output_len,
100 DMA_FROM_DEVICE);
101 if (dma_mapping_error(jrdev, dma_out)) {
102 dev_err(jrdev, "unable to map output DMA buffer\n");
103 ret = -ENOMEM;
104 goto out_unmap_in;
105 }
106
107 ctrlpriv = dev_get_drvdata(jrdev->parent);
108 moo = FIELD_GET(CSTA_MOO, rd_reg32(&ctrlpriv->jr[0]->perfmon.status));
109 if (moo != CSTA_MOO_SECURE && moo != CSTA_MOO_TRUSTED)
110 dev_warn(jrdev,
111 "using insecure test key, enable HAB to use unique device key!\n");
112
113 /*
114 * A data blob is encrypted using a blob key (BK); a random number.
115 * The BK is used as an AES-CCM key. The initial block (B0) and the
116 * initial counter (Ctr0) are generated automatically and stored in
117 * Class 1 Context DWords 0+1+2+3. The random BK is stored in the
118 * Class 1 Key Register. Operation Mode is set to AES-CCM.
119 */
120
121 init_job_desc(desc, 0);
122 append_key_as_imm(desc, info->key_mod, info->key_mod_len,
123 info->key_mod_len, CLASS_2 | KEY_DEST_CLASS_REG);
124 append_seq_in_ptr_intlen(desc, dma_in, info->input_len, 0);
125 append_seq_out_ptr_intlen(desc, dma_out, output_len, 0);
126 append_operation(desc, op);
127
128 print_hex_dump_debug("data@"__stringify(__LINE__)": ",
129 DUMP_PREFIX_ADDRESS, 16, 1, info->input,
130 info->input_len, false);
131 print_hex_dump_debug("jobdesc@"__stringify(__LINE__)": ",
132 DUMP_PREFIX_ADDRESS, 16, 1, desc,
133 desc_bytes(desc), false);
134
135 testres.err = 0;
136 init_completion(&testres.completion);
137
138 ret = caam_jr_enqueue(jrdev, desc, caam_blob_job_done, &testres);
139 if (ret == -EINPROGRESS) {
140 wait_for_completion(&testres.completion);
141 ret = testres.err;
142 print_hex_dump_debug("output@"__stringify(__LINE__)": ",
143 DUMP_PREFIX_ADDRESS, 16, 1, info->output,
144 output_len, false);
145 }
146
147 if (ret == 0)
148 info->output_len = output_len;
149
150 dma_unmap_single(jrdev, dma_out, output_len, DMA_FROM_DEVICE);
151 out_unmap_in:
152 dma_unmap_single(jrdev, dma_in, info->input_len, DMA_TO_DEVICE);
153 out_free:
154 kfree(desc);
155
156 return ret;
157 }
158 EXPORT_SYMBOL(caam_process_blob);
159
caam_blob_gen_init(void)160 struct caam_blob_priv *caam_blob_gen_init(void)
161 {
162 struct caam_drv_private *ctrlpriv;
163 struct device *jrdev;
164
165 /*
166 * caam_blob_gen_init() may expectedly fail with -ENODEV, e.g. when
167 * CAAM driver didn't probe or when SoC lacks BLOB support. An
168 * error would be harsh in this case, so we stick to info level.
169 */
170
171 jrdev = caam_jr_alloc();
172 if (IS_ERR(jrdev)) {
173 pr_info("job ring requested, but none currently available\n");
174 return ERR_PTR(-ENODEV);
175 }
176
177 ctrlpriv = dev_get_drvdata(jrdev->parent);
178 if (!ctrlpriv->blob_present) {
179 dev_info(jrdev, "no hardware blob generation support\n");
180 caam_jr_free(jrdev);
181 return ERR_PTR(-ENODEV);
182 }
183
184 return container_of(jrdev, struct caam_blob_priv, jrdev);
185 }
186 EXPORT_SYMBOL(caam_blob_gen_init);
187
caam_blob_gen_exit(struct caam_blob_priv * priv)188 void caam_blob_gen_exit(struct caam_blob_priv *priv)
189 {
190 caam_jr_free(&priv->jrdev);
191 }
192 EXPORT_SYMBOL(caam_blob_gen_exit);
193