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1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  *  EFI image loader
4  *
5  *  based partly on wine code
6  *
7  *  Copyright (c) 2016 Alexander Graf
8  */
9 
10 #include <common.h>
11 #include <cpu_func.h>
12 #include <efi_loader.h>
13 #include <pe.h>
14 
15 const efi_guid_t efi_global_variable_guid = EFI_GLOBAL_VARIABLE_GUID;
16 const efi_guid_t efi_guid_device_path = EFI_DEVICE_PATH_PROTOCOL_GUID;
17 const efi_guid_t efi_guid_loaded_image = EFI_LOADED_IMAGE_PROTOCOL_GUID;
18 const efi_guid_t efi_guid_loaded_image_device_path =
19 		EFI_LOADED_IMAGE_DEVICE_PATH_PROTOCOL_GUID;
20 const efi_guid_t efi_simple_file_system_protocol_guid =
21 		EFI_SIMPLE_FILE_SYSTEM_PROTOCOL_GUID;
22 const efi_guid_t efi_file_info_guid = EFI_FILE_INFO_GUID;
23 
24 static int machines[] = {
25 #if defined(__aarch64__)
26 	IMAGE_FILE_MACHINE_ARM64,
27 #elif defined(__arm__)
28 	IMAGE_FILE_MACHINE_ARM,
29 	IMAGE_FILE_MACHINE_THUMB,
30 	IMAGE_FILE_MACHINE_ARMNT,
31 #endif
32 
33 #if defined(__x86_64__)
34 	IMAGE_FILE_MACHINE_AMD64,
35 #elif defined(__i386__)
36 	IMAGE_FILE_MACHINE_I386,
37 #endif
38 
39 #if defined(__riscv) && (__riscv_xlen == 32)
40 	IMAGE_FILE_MACHINE_RISCV32,
41 #endif
42 
43 #if defined(__riscv) && (__riscv_xlen == 64)
44 	IMAGE_FILE_MACHINE_RISCV64,
45 #endif
46 	0 };
47 
48 /**
49  * efi_print_image_info() - print information about a loaded image
50  *
51  * If the program counter is located within the image the offset to the base
52  * address is shown.
53  *
54  * @obj:	EFI object
55  * @image:	loaded image
56  * @pc:		program counter (use NULL to suppress offset output)
57  * Return:	status code
58  */
efi_print_image_info(struct efi_loaded_image_obj * obj,struct efi_loaded_image * image,void * pc)59 static efi_status_t efi_print_image_info(struct efi_loaded_image_obj *obj,
60 					 struct efi_loaded_image *image,
61 					 void *pc)
62 {
63 	printf("UEFI image");
64 	printf(" [0x%p:0x%p]",
65 	       image->image_base, image->image_base + image->image_size - 1);
66 	if (pc && pc >= image->image_base &&
67 	    pc < image->image_base + image->image_size)
68 		printf(" pc=0x%zx", pc - image->image_base);
69 	if (image->file_path)
70 		printf(" '%pD'", image->file_path);
71 	printf("\n");
72 	return EFI_SUCCESS;
73 }
74 
75 /**
76  * efi_print_image_infos() - print information about all loaded images
77  *
78  * @pc:		program counter (use NULL to suppress offset output)
79  */
efi_print_image_infos(void * pc)80 void efi_print_image_infos(void *pc)
81 {
82 	struct efi_object *efiobj;
83 	struct efi_handler *handler;
84 
85 	list_for_each_entry(efiobj, &efi_obj_list, link) {
86 		list_for_each_entry(handler, &efiobj->protocols, link) {
87 			if (!guidcmp(handler->guid, &efi_guid_loaded_image)) {
88 				efi_print_image_info(
89 					(struct efi_loaded_image_obj *)efiobj,
90 					handler->protocol_interface, pc);
91 			}
92 		}
93 	}
94 }
95 
96 /**
97  * efi_loader_relocate() - relocate UEFI binary
98  *
99  * @rel:		pointer to the relocation table
100  * @rel_size:		size of the relocation table in bytes
101  * @efi_reloc:		actual load address of the image
102  * @pref_address:	preferred load address of the image
103  * Return:		status code
104  */
efi_loader_relocate(const IMAGE_BASE_RELOCATION * rel,unsigned long rel_size,void * efi_reloc,unsigned long pref_address)105 static efi_status_t efi_loader_relocate(const IMAGE_BASE_RELOCATION *rel,
106 			unsigned long rel_size, void *efi_reloc,
107 			unsigned long pref_address)
108 {
109 	unsigned long delta = (unsigned long)efi_reloc - pref_address;
110 	const IMAGE_BASE_RELOCATION *end;
111 	int i;
112 
113 	if (delta == 0)
114 		return EFI_SUCCESS;
115 
116 	end = (const IMAGE_BASE_RELOCATION *)((const char *)rel + rel_size);
117 	while (rel < end && rel->SizeOfBlock) {
118 		const uint16_t *relocs = (const uint16_t *)(rel + 1);
119 		i = (rel->SizeOfBlock - sizeof(*rel)) / sizeof(uint16_t);
120 		while (i--) {
121 			uint32_t offset = (uint32_t)(*relocs & 0xfff) +
122 					  rel->VirtualAddress;
123 			int type = *relocs >> EFI_PAGE_SHIFT;
124 			uint64_t *x64 = efi_reloc + offset;
125 			uint32_t *x32 = efi_reloc + offset;
126 			uint16_t *x16 = efi_reloc + offset;
127 
128 			switch (type) {
129 			case IMAGE_REL_BASED_ABSOLUTE:
130 				break;
131 			case IMAGE_REL_BASED_HIGH:
132 				*x16 += ((uint32_t)delta) >> 16;
133 				break;
134 			case IMAGE_REL_BASED_LOW:
135 				*x16 += (uint16_t)delta;
136 				break;
137 			case IMAGE_REL_BASED_HIGHLOW:
138 				*x32 += (uint32_t)delta;
139 				break;
140 			case IMAGE_REL_BASED_DIR64:
141 				*x64 += (uint64_t)delta;
142 				break;
143 #ifdef __riscv
144 			case IMAGE_REL_BASED_RISCV_HI20:
145 				*x32 = ((*x32 & 0xfffff000) + (uint32_t)delta) |
146 					(*x32 & 0x00000fff);
147 				break;
148 			case IMAGE_REL_BASED_RISCV_LOW12I:
149 			case IMAGE_REL_BASED_RISCV_LOW12S:
150 				/* We know that we're 4k aligned */
151 				if (delta & 0xfff) {
152 					printf("Unsupported reloc offset\n");
153 					return EFI_LOAD_ERROR;
154 				}
155 				break;
156 #endif
157 			default:
158 				printf("Unknown Relocation off %x type %x\n",
159 				       offset, type);
160 				return EFI_LOAD_ERROR;
161 			}
162 			relocs++;
163 		}
164 		rel = (const IMAGE_BASE_RELOCATION *)relocs;
165 	}
166 	return EFI_SUCCESS;
167 }
168 
invalidate_icache_all(void)169 void __weak invalidate_icache_all(void)
170 {
171 	/* If the system doesn't support icache_all flush, cross our fingers */
172 }
173 
174 /**
175  * efi_set_code_and_data_type() - determine the memory types to be used for code
176  *				  and data.
177  *
178  * @loaded_image_info:	image descriptor
179  * @image_type:		field Subsystem of the optional header for
180  *			Windows specific field
181  */
efi_set_code_and_data_type(struct efi_loaded_image * loaded_image_info,uint16_t image_type)182 static void efi_set_code_and_data_type(
183 			struct efi_loaded_image *loaded_image_info,
184 			uint16_t image_type)
185 {
186 	switch (image_type) {
187 	case IMAGE_SUBSYSTEM_EFI_APPLICATION:
188 		loaded_image_info->image_code_type = EFI_LOADER_CODE;
189 		loaded_image_info->image_data_type = EFI_LOADER_DATA;
190 		break;
191 	case IMAGE_SUBSYSTEM_EFI_BOOT_SERVICE_DRIVER:
192 		loaded_image_info->image_code_type = EFI_BOOT_SERVICES_CODE;
193 		loaded_image_info->image_data_type = EFI_BOOT_SERVICES_DATA;
194 		break;
195 	case IMAGE_SUBSYSTEM_EFI_RUNTIME_DRIVER:
196 	case IMAGE_SUBSYSTEM_EFI_ROM:
197 		loaded_image_info->image_code_type = EFI_RUNTIME_SERVICES_CODE;
198 		loaded_image_info->image_data_type = EFI_RUNTIME_SERVICES_DATA;
199 		break;
200 	default:
201 		printf("%s: invalid image type: %u\n", __func__, image_type);
202 		/* Let's assume it is an application */
203 		loaded_image_info->image_code_type = EFI_LOADER_CODE;
204 		loaded_image_info->image_data_type = EFI_LOADER_DATA;
205 		break;
206 	}
207 }
208 
209 /**
210  * efi_load_pe() - relocate EFI binary
211  *
212  * This function loads all sections from a PE binary into a newly reserved
213  * piece of memory. On success the entry point is returned as handle->entry.
214  *
215  * @handle:		loaded image handle
216  * @efi:		pointer to the EFI binary
217  * @loaded_image_info:	loaded image protocol
218  * Return:		status code
219  */
efi_load_pe(struct efi_loaded_image_obj * handle,void * efi,struct efi_loaded_image * loaded_image_info)220 efi_status_t efi_load_pe(struct efi_loaded_image_obj *handle, void *efi,
221 			 struct efi_loaded_image *loaded_image_info)
222 {
223 	IMAGE_NT_HEADERS32 *nt;
224 	IMAGE_DOS_HEADER *dos;
225 	IMAGE_SECTION_HEADER *sections;
226 	int num_sections;
227 	void *efi_reloc;
228 	int i;
229 	const IMAGE_BASE_RELOCATION *rel;
230 	unsigned long rel_size;
231 	int rel_idx = IMAGE_DIRECTORY_ENTRY_BASERELOC;
232 	uint64_t image_base;
233 	unsigned long virt_size = 0;
234 	int supported = 0;
235 
236 	dos = efi;
237 	if (dos->e_magic != IMAGE_DOS_SIGNATURE) {
238 		printf("%s: Invalid DOS Signature\n", __func__);
239 		return EFI_LOAD_ERROR;
240 	}
241 
242 	nt = (void *) ((char *)efi + dos->e_lfanew);
243 	if (nt->Signature != IMAGE_NT_SIGNATURE) {
244 		printf("%s: Invalid NT Signature\n", __func__);
245 		return EFI_LOAD_ERROR;
246 	}
247 
248 	for (i = 0; machines[i]; i++)
249 		if (machines[i] == nt->FileHeader.Machine) {
250 			supported = 1;
251 			break;
252 		}
253 
254 	if (!supported) {
255 		printf("%s: Machine type 0x%04x is not supported\n",
256 		       __func__, nt->FileHeader.Machine);
257 		return EFI_LOAD_ERROR;
258 	}
259 
260 	/* Calculate upper virtual address boundary */
261 	num_sections = nt->FileHeader.NumberOfSections;
262 	sections = (void *)&nt->OptionalHeader +
263 			    nt->FileHeader.SizeOfOptionalHeader;
264 
265 	for (i = num_sections - 1; i >= 0; i--) {
266 		IMAGE_SECTION_HEADER *sec = &sections[i];
267 		virt_size = max_t(unsigned long, virt_size,
268 				  sec->VirtualAddress + sec->Misc.VirtualSize);
269 	}
270 
271 	/* Read 32/64bit specific header bits */
272 	if (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR64_MAGIC) {
273 		IMAGE_NT_HEADERS64 *nt64 = (void *)nt;
274 		IMAGE_OPTIONAL_HEADER64 *opt = &nt64->OptionalHeader;
275 		image_base = opt->ImageBase;
276 		efi_set_code_and_data_type(loaded_image_info, opt->Subsystem);
277 		handle->image_type = opt->Subsystem;
278 		efi_reloc = efi_alloc(virt_size,
279 				      loaded_image_info->image_code_type);
280 		if (!efi_reloc) {
281 			printf("%s: Could not allocate %lu bytes\n",
282 			       __func__, virt_size);
283 			return EFI_OUT_OF_RESOURCES;
284 		}
285 		handle->entry = efi_reloc + opt->AddressOfEntryPoint;
286 		rel_size = opt->DataDirectory[rel_idx].Size;
287 		rel = efi_reloc + opt->DataDirectory[rel_idx].VirtualAddress;
288 		virt_size = ALIGN(virt_size, opt->SectionAlignment);
289 	} else if (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
290 		IMAGE_OPTIONAL_HEADER32 *opt = &nt->OptionalHeader;
291 		image_base = opt->ImageBase;
292 		efi_set_code_and_data_type(loaded_image_info, opt->Subsystem);
293 		handle->image_type = opt->Subsystem;
294 		efi_reloc = efi_alloc(virt_size,
295 				      loaded_image_info->image_code_type);
296 		if (!efi_reloc) {
297 			printf("%s: Could not allocate %lu bytes\n",
298 			       __func__, virt_size);
299 			return EFI_OUT_OF_RESOURCES;
300 		}
301 		handle->entry = efi_reloc + opt->AddressOfEntryPoint;
302 		rel_size = opt->DataDirectory[rel_idx].Size;
303 		rel = efi_reloc + opt->DataDirectory[rel_idx].VirtualAddress;
304 		virt_size = ALIGN(virt_size, opt->SectionAlignment);
305 	} else {
306 		printf("%s: Invalid optional header magic %x\n", __func__,
307 		       nt->OptionalHeader.Magic);
308 		return EFI_LOAD_ERROR;
309 	}
310 
311 	/* Copy PE headers */
312 	memcpy(efi_reloc, efi, sizeof(*dos) + sizeof(*nt)
313 	       + nt->FileHeader.SizeOfOptionalHeader
314 	       + num_sections * sizeof(IMAGE_SECTION_HEADER));
315 
316 	/* Load sections into RAM */
317 	for (i = num_sections - 1; i >= 0; i--) {
318 		IMAGE_SECTION_HEADER *sec = &sections[i];
319 		memset(efi_reloc + sec->VirtualAddress, 0,
320 		       sec->Misc.VirtualSize);
321 		memcpy(efi_reloc + sec->VirtualAddress,
322 		       efi + sec->PointerToRawData,
323 		       sec->SizeOfRawData);
324 	}
325 
326 	/* Run through relocations */
327 	if (efi_loader_relocate(rel, rel_size, efi_reloc,
328 				(unsigned long)image_base) != EFI_SUCCESS) {
329 		efi_free_pages((uintptr_t) efi_reloc,
330 			       (virt_size + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT);
331 		return EFI_LOAD_ERROR;
332 	}
333 
334 	/* Flush cache */
335 	flush_cache((ulong)efi_reloc,
336 		    ALIGN(virt_size, EFI_CACHELINE_SIZE));
337 	invalidate_icache_all();
338 
339 	/* Populate the loaded image interface bits */
340 	loaded_image_info->image_base = efi_reloc;
341 	loaded_image_info->image_size = virt_size;
342 
343 	return EFI_SUCCESS;
344 }
345