1 /*
2  * Copyright (c) 2017-2022, 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 #include <platform_def.h>
13 
14 /*
15  * load_addr_hi and load_addr_lo: image load address.
16  * image_id: 0 - pager, 1 - paged
17  * size: image size in bytes.
18  */
19 typedef struct optee_image {
20 	uint32_t load_addr_hi;
21 	uint32_t load_addr_lo;
22 	uint32_t image_id;
23 	uint32_t size;
24 } optee_image_t;
25 
26 #define OPTEE_PAGER_IMAGE_ID		0
27 #define OPTEE_PAGED_IMAGE_ID		1
28 
29 #define OPTEE_MAX_NUM_IMAGES		2u
30 
31 #define TEE_MAGIC_NUM_OPTEE		0x4554504f
32 /*
33  * magic: header magic number.
34  * version: OPTEE header version:
35  *		1 - not supported
36  *		2 - supported
37  * arch: OPTEE os architecture type: 0 - AARCH32, 1 - AARCH64.
38  * flags: unused currently.
39  * nb_images: number of images.
40  */
41 typedef struct optee_header {
42 	uint32_t magic;
43 	uint8_t version;
44 	uint8_t arch;
45 	uint16_t flags;
46 	uint32_t nb_images;
47 	optee_image_t optee_image_list[];
48 } optee_header_t;
49 
50 /*******************************************************************************
51  * Check if it is a valid tee header
52  * Return true if valid
53  * Return false if invalid
54  ******************************************************************************/
tee_validate_header(optee_header_t * header)55 static bool tee_validate_header(optee_header_t *header)
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 		return true;
62 	}
63 
64 	return false;
65 }
66 
optee_header_is_valid(uintptr_t header_base)67 bool optee_header_is_valid(uintptr_t header_base)
68 {
69 	return tee_validate_header((optee_header_t *)header_base);
70 }
71 
72 /*******************************************************************************
73  * Parse the OPTEE image
74  * Return 0 on success or a negative error code otherwise.
75  ******************************************************************************/
parse_optee_image(image_info_t * image_info,optee_image_t * image)76 static int parse_optee_image(image_info_t *image_info,
77 		optee_image_t *image)
78 {
79 	uintptr_t init_load_addr, free_end, requested_end;
80 	size_t init_size;
81 
82 	init_load_addr = ((uint64_t)image->load_addr_hi << 32) |
83 					image->load_addr_lo;
84 	init_size = image->size;
85 
86 	/*
87 	 * image->load_addr_hi & image->load_addr_lo set to UINT32_MAX indicate
88 	 * loader decided address; take our pre-mapped area for current image
89 	 * since arm-tf could not allocate memory dynamically
90 	 */
91 	if ((image->load_addr_hi == UINT32_MAX) &&
92 	    (image->load_addr_lo == UINT32_MAX)) {
93 		init_load_addr = image_info->image_base;
94 	}
95 
96 	/* Check that the default end address doesn't overflow */
97 	if (check_uptr_overflow(image_info->image_base,
98 				image_info->image_max_size - 1))
99 		return -1;
100 	free_end = image_info->image_base + (image_info->image_max_size - 1);
101 
102 	/* Check that the image end address doesn't overflow */
103 	if (check_uptr_overflow(init_load_addr, init_size - 1))
104 		return -1;
105 	requested_end = init_load_addr + (init_size - 1);
106 	/*
107 	 * Check that the requested RAM location is within reserved
108 	 * space for OPTEE.
109 	 */
110 	if (!((init_load_addr >= image_info->image_base) &&
111 			(requested_end <= free_end))) {
112 		WARN("The load address in optee header %p - %p is not in reserved area: %p - %p.\n",
113 				(void *)init_load_addr,
114 				(void *)(init_load_addr + init_size),
115 				(void *)image_info->image_base,
116 				(void *)(image_info->image_base +
117 					image_info->image_max_size));
118 		return -1;
119 	}
120 
121 	/*
122 	 * Remove the skip attr from image_info, the image will be loaded.
123 	 * The default attr in image_info is "IMAGE_ATTRIB_SKIP_LOADING", which
124 	 * mean the image will not be loaded. Here, we parse the header image to
125 	 * know that the extra image need to be loaded, so remove the skip attr.
126 	 */
127 	image_info->h.attr &= ~IMAGE_ATTRIB_SKIP_LOADING;
128 
129 	/* Update image base and size of image_info */
130 	image_info->image_base = init_load_addr;
131 	image_info->image_size = init_size;
132 
133 	return 0;
134 }
135 
136 /*******************************************************************************
137  * Parse the OPTEE header
138  * Return 0 on success or a negative error code otherwise.
139  ******************************************************************************/
parse_optee_header(entry_point_info_t * header_ep,image_info_t * pager_image_info,image_info_t * paged_image_info)140 int parse_optee_header(entry_point_info_t *header_ep,
141 		image_info_t *pager_image_info,
142 		image_info_t *paged_image_info)
143 
144 {
145 	optee_header_t *header;
146 	uint32_t num;
147 	int ret;
148 
149 	assert(header_ep);
150 	header = (optee_header_t *)header_ep->pc;
151 	assert(header);
152 
153 	/* Print the OPTEE header information */
154 	INFO("OPTEE ep=0x%x\n", (unsigned int)header_ep->pc);
155 	INFO("OPTEE header info:\n");
156 	INFO("      magic=0x%x\n", header->magic);
157 	INFO("      version=0x%x\n", header->version);
158 	INFO("      arch=0x%x\n", header->arch);
159 	INFO("      flags=0x%x\n", header->flags);
160 	INFO("      nb_images=0x%x\n", header->nb_images);
161 
162 	/*
163 	 * OPTEE image has 3 types:
164 	 *
165 	 * 1. Plain OPTEE bin without header.
166 	 *	Original bin without header, return directly,
167 	 *	BL32_EXTRA1_IMAGE_ID and BL32_EXTRA2_IMAGE_ID will be skipped.
168 	 *
169 	 * 2. OPTEE bin with header bin, but no paging.
170 	 *	Header available and nb_images = 1, remove skip attr for
171 	 *	BL32_EXTRA1_IMAGE_ID. BL32_EXTRA1_IMAGE_ID will be loaded,
172 	 *	and BL32_EXTRA2_IMAGE_ID be skipped.
173 	 *
174 	 * 3. OPTEE image with paging support.
175 	 *	Header available and nb_images = 2, there are 3 bins: header,
176 	 *	pager and pageable. Remove skip attr for BL32_EXTRA1_IMAGE_ID
177 	 *	and BL32_EXTRA2_IMAGE_ID to load pager and paged bin.
178 	 */
179 	if (!tee_validate_header(header)) {
180 		INFO("Invalid OPTEE header, set legacy mode.\n");
181 #ifdef __aarch64__
182 		header_ep->args.arg0 = MODE_RW_64;
183 #else
184 		header_ep->args.arg0 = MODE_RW_32;
185 #endif
186 		return 0;
187 	}
188 
189 	/* Parse OPTEE image */
190 	for (num = 0U; num < header->nb_images; num++) {
191 		if (header->optee_image_list[num].image_id ==
192 				OPTEE_PAGER_IMAGE_ID) {
193 			ret = parse_optee_image(pager_image_info,
194 				&header->optee_image_list[num]);
195 		} else if (header->optee_image_list[num].image_id ==
196 				OPTEE_PAGED_IMAGE_ID) {
197 			if (paged_image_info == NULL) {
198 				if (header->optee_image_list[num].size != 0U) {
199 					ERROR("Paged image is not supported\n");
200 					return -1;
201 				}
202 
203 				continue;
204 			} else {
205 				ret = parse_optee_image(paged_image_info,
206 							&header->optee_image_list[num]);
207 			}
208 		} else {
209 			ERROR("Parse optee image failed.\n");
210 			return -1;
211 		}
212 
213 		if (ret != 0)
214 			return -1;
215 	}
216 
217 	/*
218 	 * Update "pc" value which should comes from pager image. After the
219 	 * header image is parsed, it will be unuseful, and the actual
220 	 * execution image after BL31 is pager image.
221 	 */
222 	header_ep->pc =	pager_image_info->image_base;
223 
224 	/*
225 	 * The paged load address and size are populated in
226 	 * header image arguments so that can be read by the
227 	 * BL32 SPD.
228 	 */
229 	if (paged_image_info != NULL) {
230 		header_ep->args.arg1 = paged_image_info->image_base;
231 		header_ep->args.arg2 = paged_image_info->image_size;
232 	}
233 
234 	/* Set OPTEE runtime arch - aarch32/aarch64 */
235 	if (header->arch == 0) {
236 		header_ep->args.arg0 = MODE_RW_32;
237 	} else {
238 #ifdef __aarch64__
239 		header_ep->args.arg0 = MODE_RW_64;
240 #else
241 		ERROR("Cannot boot an AArch64 OP-TEE\n");
242 		return -1;
243 #endif
244 	}
245 
246 	return 0;
247 }
248