1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright 2020 NXP
4  */
5 
6 #include <command.h>
7 #include <common.h>
8 #include <env.h>
9 #include <errno.h>
10 #include <image.h>
11 #include <malloc.h>
12 #include <mmc.h>
13 #include <tee.h>
14 #include <tee/optee_ta_avb.h>
15 
16 static struct udevice *tee;
17 static u32 session;
18 
avb_ta_open_session(void)19 static int avb_ta_open_session(void)
20 {
21 	const struct tee_optee_ta_uuid uuid = TA_AVB_UUID;
22 	struct tee_open_session_arg arg;
23 	int rc;
24 
25 	tee = tee_find_device(tee, NULL, NULL, NULL);
26 	if (!tee)
27 		return -ENODEV;
28 
29 	memset(&arg, 0, sizeof(arg));
30 	tee_optee_ta_uuid_to_octets(arg.uuid, &uuid);
31 	rc = tee_open_session(tee, &arg, 0, NULL);
32 	if (!rc)
33 		session = arg.session;
34 
35 	return 0;
36 }
37 
invoke_func(u32 func,ulong num_param,struct tee_param * param)38 static int invoke_func(u32 func, ulong num_param, struct tee_param *param)
39 {
40 	struct tee_invoke_arg arg;
41 
42 	if (!tee)
43 		if (avb_ta_open_session())
44 			return -ENODEV;
45 
46 	memset(&arg, 0, sizeof(arg));
47 	arg.func = func;
48 	arg.session = session;
49 
50 	if (tee_invoke_func(tee, &arg, num_param, param))
51 		return -EFAULT;
52 	switch (arg.ret) {
53 	case TEE_SUCCESS:
54 		return 0;
55 	case TEE_ERROR_OUT_OF_MEMORY:
56 	case TEE_ERROR_STORAGE_NO_SPACE:
57 		return -ENOSPC;
58 	case TEE_ERROR_ITEM_NOT_FOUND:
59 		return -EIO;
60 	case TEE_ERROR_TARGET_DEAD:
61 		/*
62 		 * The TA has paniced, close the session to reload the TA
63 		 * for the next request.
64 		 */
65 		tee_close_session(tee, session);
66 		tee = NULL;
67 		return -EIO;
68 	default:
69 		return -EIO;
70 	}
71 }
72 
read_persistent_value(const char * name,size_t buffer_size,u8 * out_buffer,size_t * out_num_bytes_read)73 static int read_persistent_value(const char *name,
74 				 size_t buffer_size,
75 				 u8 *out_buffer,
76 				 size_t *out_num_bytes_read)
77 {
78 	int rc = 0;
79 	struct tee_shm *shm_name;
80 	struct tee_shm *shm_buf;
81 	struct tee_param param[2];
82 	size_t name_size = strlen(name) + 1;
83 
84 	if (!tee)
85 		if (avb_ta_open_session())
86 			return -ENODEV;
87 
88 	rc = tee_shm_alloc(tee, name_size,
89 			   TEE_SHM_ALLOC, &shm_name);
90 	if (rc)
91 		return -ENOMEM;
92 
93 	rc = tee_shm_alloc(tee, buffer_size,
94 			   TEE_SHM_ALLOC, &shm_buf);
95 	if (rc) {
96 		rc = -ENOMEM;
97 		goto free_name;
98 	}
99 
100 	memcpy(shm_name->addr, name, name_size);
101 
102 	memset(param, 0, sizeof(param));
103 	param[0].attr = TEE_PARAM_ATTR_TYPE_MEMREF_INPUT;
104 	param[0].u.memref.shm = shm_name;
105 	param[0].u.memref.size = name_size;
106 	param[1].attr = TEE_PARAM_ATTR_TYPE_MEMREF_INOUT;
107 	param[1].u.memref.shm = shm_buf;
108 	param[1].u.memref.size = buffer_size;
109 
110 	rc = invoke_func(TA_AVB_CMD_READ_PERSIST_VALUE,
111 			 2, param);
112 	if (rc)
113 		goto out;
114 
115 	if (param[1].u.memref.size > buffer_size) {
116 		rc = -EINVAL;
117 		goto out;
118 	}
119 
120 	*out_num_bytes_read = param[1].u.memref.size;
121 
122 	memcpy(out_buffer, shm_buf->addr, *out_num_bytes_read);
123 
124 out:
125 	tee_shm_free(shm_buf);
126 free_name:
127 	tee_shm_free(shm_name);
128 
129 	return rc;
130 }
131 
write_persistent_value(const char * name,size_t value_size,const u8 * value)132 static int write_persistent_value(const char *name,
133 				  size_t value_size,
134 				  const u8 *value)
135 {
136 	int rc = 0;
137 	struct tee_shm *shm_name;
138 	struct tee_shm *shm_buf;
139 	struct tee_param param[2];
140 	size_t name_size = strlen(name) + 1;
141 
142 	if (!tee) {
143 		if (avb_ta_open_session())
144 			return -ENODEV;
145 	}
146 	if (!value_size)
147 		return -EINVAL;
148 
149 	rc = tee_shm_alloc(tee, name_size,
150 			   TEE_SHM_ALLOC, &shm_name);
151 	if (rc)
152 		return -ENOMEM;
153 
154 	rc = tee_shm_alloc(tee, value_size,
155 			   TEE_SHM_ALLOC, &shm_buf);
156 	if (rc) {
157 		rc = -ENOMEM;
158 		goto free_name;
159 	}
160 
161 	memcpy(shm_name->addr, name, name_size);
162 	memcpy(shm_buf->addr, value, value_size);
163 
164 	memset(param, 0, sizeof(param));
165 	param[0].attr = TEE_PARAM_ATTR_TYPE_MEMREF_INPUT;
166 	param[0].u.memref.shm = shm_name;
167 	param[0].u.memref.size = name_size;
168 	param[1].attr = TEE_PARAM_ATTR_TYPE_MEMREF_INPUT;
169 	param[1].u.memref.shm = shm_buf;
170 	param[1].u.memref.size = value_size;
171 
172 	rc = invoke_func(TA_AVB_CMD_WRITE_PERSIST_VALUE,
173 			 2, param);
174 	if (rc)
175 		goto out;
176 
177 out:
178 	tee_shm_free(shm_buf);
179 free_name:
180 	tee_shm_free(shm_name);
181 
182 	return rc;
183 }
184 
do_optee_rpmb_read(struct cmd_tbl * cmdtp,int flag,int argc,char * const argv[])185 int do_optee_rpmb_read(struct cmd_tbl *cmdtp, int flag, int argc,
186 		       char * const argv[])
187 {
188 	const char *name;
189 	size_t bytes;
190 	size_t bytes_read;
191 	void *buffer;
192 	char *endp;
193 
194 	if (argc != 3)
195 		return CMD_RET_USAGE;
196 
197 	name = argv[1];
198 	bytes = simple_strtoul(argv[2], &endp, 10);
199 	if (*endp && *endp != '\n')
200 		return CMD_RET_USAGE;
201 
202 	buffer = malloc(bytes);
203 	if (!buffer)
204 		return CMD_RET_FAILURE;
205 
206 	if (read_persistent_value(name, bytes, buffer, &bytes_read) == 0) {
207 		printf("Read %zu bytes, value = %s\n", bytes_read,
208 		       (char *)buffer);
209 		free(buffer);
210 		return CMD_RET_SUCCESS;
211 	}
212 
213 	printf("Failed to read persistent value\n");
214 
215 	free(buffer);
216 
217 	return CMD_RET_FAILURE;
218 }
219 
do_optee_rpmb_write(struct cmd_tbl * cmdtp,int flag,int argc,char * const argv[])220 int do_optee_rpmb_write(struct cmd_tbl *cmdtp, int flag, int argc,
221 			char * const argv[])
222 {
223 	const char *name;
224 	const char *value;
225 
226 	if (argc != 3)
227 		return CMD_RET_USAGE;
228 
229 	name = argv[1];
230 	value = argv[2];
231 
232 	if (write_persistent_value(name, strlen(value) + 1,
233 				   (const uint8_t *)value) == 0) {
234 		printf("Wrote %zu bytes\n", strlen(value) + 1);
235 		return CMD_RET_SUCCESS;
236 	}
237 
238 	printf("Failed to write persistent value\n");
239 
240 	return CMD_RET_FAILURE;
241 }
242 
243 static struct cmd_tbl cmd_optee_rpmb[] = {
244 	U_BOOT_CMD_MKENT(read_pvalue, 3, 0, do_optee_rpmb_read, "", ""),
245 	U_BOOT_CMD_MKENT(write_pvalue, 3, 0, do_optee_rpmb_write, "", ""),
246 };
247 
do_optee_rpmb(struct cmd_tbl * cmdtp,int flag,int argc,char * const argv[])248 static int do_optee_rpmb(struct cmd_tbl *cmdtp, int flag, int argc,
249 			 char * const argv[])
250 {
251 	struct cmd_tbl *cp;
252 
253 	cp = find_cmd_tbl(argv[1], cmd_optee_rpmb, ARRAY_SIZE(cmd_optee_rpmb));
254 
255 	argc--;
256 	argv++;
257 
258 	if (!cp || argc > cp->maxargs)
259 		return CMD_RET_USAGE;
260 
261 	if (flag == CMD_FLAG_REPEAT)
262 		return CMD_RET_FAILURE;
263 
264 	return cp->cmd(cmdtp, flag, argc, argv);
265 }
266 
267 U_BOOT_CMD (
268 	optee_rpmb, 29, 0, do_optee_rpmb,
269 	"Provides commands for testing secure storage on RPMB on OPTEE",
270 	"read_pvalue <name> <bytes> - read a persistent value <name>\n"
271 	"optee_rpmb write_pvalue <name> <value> - write a persistent value <name>\n"
272 	);
273