xref: /optee_os/core/pta/device.c (revision ed3fa831cdd6c545bf2813de8aeccc2564387983)
1 // SPDX-License-Identifier: BSD-2-Clause
2 /*
3  * Copyright (C) 2019, Linaro Limited
4  */
5 
6 /*
7  * This pseudo TA is used by normal world OS TEE driver to fetch pseudo TA's
8  * UUIDs which can act as TEE bus devices.
9  */
10 
11 #include <config.h>
12 #include <kernel/early_ta.h>
13 #include <kernel/linker.h>
14 #include <kernel/pseudo_ta.h>
15 #include <kernel/tee_ta_manager.h>
16 #include <pta_device.h>
17 #include <string.h>
18 #include <tee/uuid.h>
19 #include <user_ta_header.h>
20 
21 #define PTA_NAME "device.pta"
22 
23 static void add_ta(uint32_t flags, const TEE_UUID *uuid, uint8_t *buf,
24 		   uint32_t blen, uint32_t *pos)
25 {
26 	if (flags & TA_FLAG_DEVICE_ENUM) {
27 		if (*pos + sizeof(*uuid) <= blen)
28 			tee_uuid_to_octets(buf + *pos, uuid);
29 
30 		*pos += sizeof(*uuid);
31 	}
32 }
33 
34 static TEE_Result get_devices(uint32_t types,
35 			      TEE_Param params[TEE_NUM_PARAMS])
36 {
37 	const struct pseudo_ta_head *ta = NULL;
38 	const struct early_ta *eta = NULL;
39 	void *buf = NULL;
40 	uint32_t blen = 0;
41 	uint32_t pos = 0;
42 
43 	if (types != TEE_PARAM_TYPES(TEE_PARAM_TYPE_MEMREF_OUTPUT,
44 				     TEE_PARAM_TYPE_NONE,
45 				     TEE_PARAM_TYPE_NONE,
46 				     TEE_PARAM_TYPE_NONE))
47 		return TEE_ERROR_BAD_PARAMETERS;
48 
49 	if (!params[0].memref.buffer && (params[0].memref.size > 0))
50 		return TEE_ERROR_BAD_PARAMETERS;
51 
52 	buf =  params[0].memref.buffer;
53 	blen = params[0].memref.size;
54 
55 	SCATTERED_ARRAY_FOREACH(ta, pseudo_tas, struct pseudo_ta_head)
56 		add_ta(ta->flags, &ta->uuid, buf, blen, &pos);
57 
58 	if (IS_ENABLED(CFG_EARLY_TA))
59 		for_each_early_ta(eta)
60 			add_ta(eta->flags, &eta->uuid, buf, blen, &pos);
61 
62 	params[0].memref.size = pos;
63 	if (pos > blen)
64 		return TEE_ERROR_SHORT_BUFFER;
65 
66 	return TEE_SUCCESS;
67 }
68 
69 static TEE_Result invoke_command(void *pSessionContext __unused,
70 				 uint32_t nCommandID, uint32_t nParamTypes,
71 				 TEE_Param pParams[TEE_NUM_PARAMS])
72 {
73 	switch (nCommandID) {
74 	case PTA_CMD_GET_DEVICES:
75 		return get_devices(nParamTypes, pParams);
76 	default:
77 		break;
78 	}
79 
80 	return TEE_ERROR_NOT_IMPLEMENTED;
81 }
82 
83 pseudo_ta_register(.uuid = PTA_DEVICE_UUID, .name = PTA_NAME,
84 		   .flags = PTA_DEFAULT_FLAGS,
85 		   .invoke_command_entry_point = invoke_command);
86