1 // SPDX-License-Identifier: BSD-2-Clause
2 /*
3 * Copyright (C) 2018, Linaro Limited
4 * Copyright (c) 2021, EPAM Systems. All rights reserved.
5 *
6 * Based on plat-synquacer/rng_pta.c
7 *
8 */
9
10 #include <assert.h>
11 #include <config.h>
12 #include <crypto/crypto.h>
13 #include <kernel/pseudo_ta.h>
14 #include <pta_rng.h>
15 #include <rng_support.h>
16
17 #define PTA_NAME "rng.pta"
18
19 /* This PTA only works with hardware random number generators */
20 static_assert(!IS_ENABLED(CFG_WITH_SOFTWARE_PRNG));
21
rng_get_entropy(uint32_t types,TEE_Param params[TEE_NUM_PARAMS])22 static TEE_Result rng_get_entropy(uint32_t types,
23 TEE_Param params[TEE_NUM_PARAMS])
24 {
25 uint8_t *e = NULL;
26
27 if (types != TEE_PARAM_TYPES(TEE_PARAM_TYPE_MEMREF_INOUT,
28 TEE_PARAM_TYPE_NONE,
29 TEE_PARAM_TYPE_NONE,
30 TEE_PARAM_TYPE_NONE)) {
31 DMSG("bad parameters types: 0x%" PRIx32, types);
32 return TEE_ERROR_BAD_PARAMETERS;
33 }
34
35 e = (uint8_t *)params[0].memref.buffer;
36 if (!e)
37 return TEE_ERROR_BAD_PARAMETERS;
38
39 return crypto_rng_read(e, params[0].memref.size);
40 }
41
rng_get_info(uint32_t types,TEE_Param params[TEE_NUM_PARAMS])42 static TEE_Result rng_get_info(uint32_t types,
43 TEE_Param params[TEE_NUM_PARAMS])
44 {
45 if (types != TEE_PARAM_TYPES(TEE_PARAM_TYPE_VALUE_OUTPUT,
46 TEE_PARAM_TYPE_NONE,
47 TEE_PARAM_TYPE_NONE,
48 TEE_PARAM_TYPE_NONE)) {
49 DMSG("bad parameters types: 0x%" PRIx32, types);
50 return TEE_ERROR_BAD_PARAMETERS;
51 }
52
53 params[0].value.a = CFG_HWRNG_RATE;
54 params[0].value.b = CFG_HWRNG_QUALITY;
55
56 return TEE_SUCCESS;
57 }
58
invoke_command(void * session __unused,uint32_t cmd,uint32_t ptypes,TEE_Param params[TEE_NUM_PARAMS])59 static TEE_Result invoke_command(void *session __unused,
60 uint32_t cmd, uint32_t ptypes,
61 TEE_Param params[TEE_NUM_PARAMS])
62 {
63 FMSG(PTA_NAME" command %#"PRIx32" ptypes %#"PRIx32, cmd, ptypes);
64
65 switch (cmd) {
66 case PTA_CMD_GET_ENTROPY:
67 return rng_get_entropy(ptypes, params);
68 case PTA_CMD_GET_RNG_INFO:
69 return rng_get_info(ptypes, params);
70 default:
71 break;
72 }
73
74 return TEE_ERROR_NOT_IMPLEMENTED;
75 }
76
77 pseudo_ta_register(.uuid = PTA_RNG_UUID, .name = PTA_NAME,
78 .flags = PTA_DEFAULT_FLAGS | TA_FLAG_CONCURRENT |
79 TA_FLAG_DEVICE_ENUM,
80 .invoke_command_entry_point = invoke_command);
81