1 /*
2  * Copyright (c) 2017-2020, ARM Limited and Contributors. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <assert.h>
8 
9 #include <common/debug.h>
10 #include <lib/optee_utils.h>
11 
12 /*
13  * load_addr_hi and load_addr_lo: image load address.
14  * image_id: 0 - pager, 1 - paged
15  * size: image size in bytes.
16  */
17 typedef struct optee_image {
18 	uint32_t load_addr_hi;
19 	uint32_t load_addr_lo;
20 	uint32_t image_id;
21 	uint32_t size;
22 } optee_image_t;
23 
24 #define OPTEE_PAGER_IMAGE_ID		0
25 #define OPTEE_PAGED_IMAGE_ID		1
26 
27 #define OPTEE_MAX_NUM_IMAGES		2u
28 
29 #define TEE_MAGIC_NUM_OPTEE		0x4554504f
30 /*
31  * magic: header magic number.
32  * version: OPTEE header version:
33  *		1 - not supported
34  *		2 - supported
35  * arch: OPTEE os architecture type: 0 - AARCH32, 1 - AARCH64.
36  * flags: unused currently.
37  * nb_images: number of images.
38  */
39 typedef struct optee_header {
40 	uint32_t magic;
41 	uint8_t version;
42 	uint8_t arch;
43 	uint16_t flags;
44 	uint32_t nb_images;
45 	optee_image_t optee_image_list[];
46 } optee_header_t;
47 
48 /*******************************************************************************
49  * Check if it is a valid tee header
50  * Return 1 if valid
51  * Return 0 if invalid
52  ******************************************************************************/
tee_validate_header(optee_header_t * header)53 static inline int tee_validate_header(optee_header_t *header)
54 {
55 	int valid = 0;
56 
57 	if ((header->magic == TEE_MAGIC_NUM_OPTEE) &&
58 		(header->version == 2u) &&
59 		(header->nb_images > 0u) &&
60 		(header->nb_images <= OPTEE_MAX_NUM_IMAGES)) {
61 		valid = 1;
62 	}
63 
64 	else {
65 		WARN("Not a known TEE, use default loading options.\n");
66 	}
67 
68 	return valid;
69 }
70 
71 /*******************************************************************************
72  * Parse the OPTEE image
73  * Return 0 on success or a negative error code otherwise.
74  ******************************************************************************/
parse_optee_image(image_info_t * image_info,optee_image_t * image)75 static int parse_optee_image(image_info_t *image_info,
76 		optee_image_t *image)
77 {
78 	uintptr_t init_load_addr, free_end, requested_end;
79 	size_t init_size;
80 
81 	init_load_addr = ((uint64_t)image->load_addr_hi << 32) |
82 					image->load_addr_lo;
83 	init_size = image->size;
84 
85 	/*
86 	 * -1 indicates loader decided address; take our pre-mapped area
87 	 * for current image since arm-tf could not allocate memory dynamically
88 	 */
89 	if (init_load_addr == -1)
90 		init_load_addr = image_info->image_base;
91 
92 	/* Check that the default end address doesn't overflow */
93 	if (check_uptr_overflow(image_info->image_base,
94 				image_info->image_max_size - 1))
95 		return -1;
96 	free_end = image_info->image_base + (image_info->image_max_size - 1);
97 
98 	/* Check that the image end address doesn't overflow */
99 	if (check_uptr_overflow(init_load_addr, init_size - 1))
100 		return -1;
101 	requested_end = init_load_addr + (init_size - 1);
102 	/*
103 	 * Check that the requested RAM location is within reserved
104 	 * space for OPTEE.
105 	 */
106 	if (!((init_load_addr >= image_info->image_base) &&
107 			(requested_end <= free_end))) {
108 		WARN("The load address in optee header %p - %p is not in reserved area: %p - %p.\n",
109 				(void *)init_load_addr,
110 				(void *)(init_load_addr + init_size),
111 				(void *)image_info->image_base,
112 				(void *)(image_info->image_base +
113 					image_info->image_max_size));
114 		return -1;
115 	}
116 
117 	/*
118 	 * Remove the skip attr from image_info, the image will be loaded.
119 	 * The default attr in image_info is "IMAGE_ATTRIB_SKIP_LOADING", which
120 	 * mean the image will not be loaded. Here, we parse the header image to
121 	 * know that the extra image need to be loaded, so remove the skip attr.
122 	 */
123 	image_info->h.attr &= ~IMAGE_ATTRIB_SKIP_LOADING;
124 
125 	/* Update image base and size of image_info */
126 	image_info->image_base = init_load_addr;
127 	image_info->image_size = init_size;
128 
129 	return 0;
130 }
131 
132 /*******************************************************************************
133  * Parse the OPTEE header
134  * Return 0 on success or a negative error code otherwise.
135  ******************************************************************************/
parse_optee_header(entry_point_info_t * header_ep,image_info_t * pager_image_info,image_info_t * paged_image_info)136 int parse_optee_header(entry_point_info_t *header_ep,
137 		image_info_t *pager_image_info,
138 		image_info_t *paged_image_info)
139 
140 {
141 	optee_header_t *header;
142 	int num, ret;
143 
144 	assert(header_ep);
145 	header = (optee_header_t *)header_ep->pc;
146 	assert(header);
147 
148 	/* Print the OPTEE header information */
149 	INFO("OPTEE ep=0x%x\n", (unsigned int)header_ep->pc);
150 	INFO("OPTEE header info:\n");
151 	INFO("      magic=0x%x\n", header->magic);
152 	INFO("      version=0x%x\n", header->version);
153 	INFO("      arch=0x%x\n", header->arch);
154 	INFO("      flags=0x%x\n", header->flags);
155 	INFO("      nb_images=0x%x\n", header->nb_images);
156 
157 	/*
158 	 * OPTEE image has 3 types:
159 	 *
160 	 * 1. Plain OPTEE bin without header.
161 	 *	Original bin without header, return directly,
162 	 *	BL32_EXTRA1_IMAGE_ID and BL32_EXTRA2_IMAGE_ID will be skipped.
163 	 *
164 	 * 2. OPTEE bin with header bin, but no paging.
165 	 *	Header available and nb_images = 1, remove skip attr for
166 	 *	BL32_EXTRA1_IMAGE_ID. BL32_EXTRA1_IMAGE_ID will be loaded,
167 	 *	and BL32_EXTRA2_IMAGE_ID be skipped.
168 	 *
169 	 * 3. OPTEE image with paging support.
170 	 *	Header available and nb_images = 2, there are 3 bins: header,
171 	 *	pager and pageable. Remove skip attr for BL32_EXTRA1_IMAGE_ID
172 	 *	and BL32_EXTRA2_IMAGE_ID to load pager and paged bin.
173 	 */
174 	if (!tee_validate_header(header)) {
175 		INFO("Invalid OPTEE header, set legacy mode.\n");
176 #ifdef __aarch64__
177 		header_ep->args.arg0 = MODE_RW_64;
178 #else
179 		header_ep->args.arg0 = MODE_RW_32;
180 #endif
181 		return 0;
182 	}
183 
184 	/* Parse OPTEE image */
185 	for (num = 0; num < header->nb_images; num++) {
186 		if (header->optee_image_list[num].image_id ==
187 				OPTEE_PAGER_IMAGE_ID) {
188 			ret = parse_optee_image(pager_image_info,
189 				&header->optee_image_list[num]);
190 		} else if (header->optee_image_list[num].image_id ==
191 				OPTEE_PAGED_IMAGE_ID) {
192 			ret = parse_optee_image(paged_image_info,
193 				&header->optee_image_list[num]);
194 		} else {
195 			ERROR("Parse optee image failed.\n");
196 			return -1;
197 		}
198 
199 		if (ret != 0)
200 			return -1;
201 	}
202 
203 	/*
204 	 * Update "pc" value which should comes from pager image. After the
205 	 * header image is parsed, it will be unuseful, and the actual
206 	 * execution image after BL31 is pager image.
207 	 */
208 	header_ep->pc =	pager_image_info->image_base;
209 
210 	/*
211 	 * The paged load address and size are populated in
212 	 * header image arguments so that can be read by the
213 	 * BL32 SPD.
214 	 */
215 	header_ep->args.arg1 = paged_image_info->image_base;
216 	header_ep->args.arg2 = paged_image_info->image_size;
217 
218 	/* Set OPTEE runtime arch - aarch32/aarch64 */
219 	if (header->arch == 0) {
220 		header_ep->args.arg0 = MODE_RW_32;
221 	} else {
222 #ifdef __aarch64__
223 		header_ep->args.arg0 = MODE_RW_64;
224 #else
225 		ERROR("Cannot boot an AArch64 OP-TEE\n");
226 		return -1;
227 #endif
228 	}
229 
230 	return 0;
231 }
232