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