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