1 /*
2  * Copyright (c) 2014-2017, ARM Limited and Contributors. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <assert.h>
8 #include <bl_common.h>
9 #include <debug.h>
10 #include <errno.h>
11 #include <firmware_image_package.h>
12 #include <io_driver.h>
13 #include <io_fip.h>
14 #include <io_storage.h>
15 #include <platform.h>
16 #include <platform_def.h>
17 #include <stdint.h>
18 #include <string.h>
19 #include <utils.h>
20 #include <uuid.h>
21 
22 /* Useful for printing UUIDs when debugging.*/
23 #define PRINT_UUID2(x)								\
24 	"%08x-%04hx-%04hx-%02hhx%02hhx-%02hhx%02hhx%02hhx%02hhx%02hhx%02hhx",	\
25 		x.time_low, x.time_mid, x.time_hi_and_version,			\
26 		x.clock_seq_hi_and_reserved, x.clock_seq_low,			\
27 		x.node[0], x.node[1], x.node[2], x.node[3],			\
28 		x.node[4], x.node[5]
29 
30 typedef struct {
31 	/* Put file_pos above the struct to allow {0} on static init.
32 	 * It is a workaround for a known bug in GCC
33 	 * http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53119
34 	 */
35 	unsigned int file_pos;
36 	fip_toc_entry_t entry;
37 } file_state_t;
38 
39 static const uuid_t uuid_null = {0};
40 static file_state_t current_file = {0};
41 static uintptr_t backend_dev_handle;
42 static uintptr_t backend_image_spec;
43 
44 
45 /* Firmware Image Package driver functions */
46 static int fip_dev_open(const uintptr_t dev_spec, io_dev_info_t **dev_info);
47 static int fip_file_open(io_dev_info_t *dev_info, const uintptr_t spec,
48 			  io_entity_t *entity);
49 static int fip_file_len(io_entity_t *entity, size_t *length);
50 static int fip_file_read(io_entity_t *entity, uintptr_t buffer, size_t length,
51 			  size_t *length_read);
52 static int fip_file_close(io_entity_t *entity);
53 static int fip_dev_init(io_dev_info_t *dev_info, const uintptr_t init_params);
54 static int fip_dev_close(io_dev_info_t *dev_info);
55 
56 
57 /* Return 0 for equal uuids. */
compare_uuids(const uuid_t * uuid1,const uuid_t * uuid2)58 static inline int compare_uuids(const uuid_t *uuid1, const uuid_t *uuid2)
59 {
60 	return memcmp(uuid1, uuid2, sizeof(uuid_t));
61 }
62 
63 
64 /* TODO: We could check version numbers or do a package checksum? */
is_valid_header(fip_toc_header_t * header)65 static inline int is_valid_header(fip_toc_header_t *header)
66 {
67 	if ((header->name == TOC_HEADER_NAME) && (header->serial_number != 0)) {
68 		return 1;
69 	} else {
70 		return 0;
71 	}
72 }
73 
74 
75 /* Identify the device type as a virtual driver */
device_type_fip(void)76 io_type_t device_type_fip(void)
77 {
78 	return IO_TYPE_FIRMWARE_IMAGE_PACKAGE;
79 }
80 
81 
82 static const io_dev_connector_t fip_dev_connector = {
83 	.dev_open = fip_dev_open
84 };
85 
86 
87 static const io_dev_funcs_t fip_dev_funcs = {
88 	.type = device_type_fip,
89 	.open = fip_file_open,
90 	.seek = NULL,
91 	.size = fip_file_len,
92 	.read = fip_file_read,
93 	.write = NULL,
94 	.close = fip_file_close,
95 	.dev_init = fip_dev_init,
96 	.dev_close = fip_dev_close,
97 };
98 
99 
100 /* No state associated with this device so structure can be const */
101 static const io_dev_info_t fip_dev_info = {
102 	.funcs = &fip_dev_funcs,
103 	.info = (uintptr_t)NULL
104 };
105 
106 
107 /* Open a connection to the FIP device */
fip_dev_open(const uintptr_t dev_spec __unused,io_dev_info_t ** dev_info)108 static int fip_dev_open(const uintptr_t dev_spec __unused,
109 			 io_dev_info_t **dev_info)
110 {
111 	assert(dev_info != NULL);
112 	*dev_info = (io_dev_info_t *)&fip_dev_info; /* cast away const */
113 
114 	return 0;
115 }
116 
117 
118 /* Do some basic package checks. */
fip_dev_init(io_dev_info_t * dev_info,const uintptr_t init_params)119 static int fip_dev_init(io_dev_info_t *dev_info, const uintptr_t init_params)
120 {
121 	int result;
122 	unsigned int image_id = (unsigned int)init_params;
123 	uintptr_t backend_handle;
124 	fip_toc_header_t header;
125 	size_t bytes_read;
126 
127 	/* Obtain a reference to the image by querying the platform layer */
128 	result = plat_get_image_source(image_id, &backend_dev_handle,
129 				       &backend_image_spec);
130 	if (result != 0) {
131 		WARN("Failed to obtain reference to image id=%u (%i)\n",
132 			image_id, result);
133 		result = -ENOENT;
134 		goto fip_dev_init_exit;
135 	}
136 
137 	/* Attempt to access the FIP image */
138 	result = io_open(backend_dev_handle, backend_image_spec,
139 			 &backend_handle);
140 	if (result != 0) {
141 		WARN("Failed to access image id=%u (%i)\n", image_id, result);
142 		result = -ENOENT;
143 		goto fip_dev_init_exit;
144 	}
145 
146 	result = io_read(backend_handle, (uintptr_t)&header, sizeof(header),
147 			&bytes_read);
148 	if (result == 0) {
149 		if (!is_valid_header(&header)) {
150 			WARN("Firmware Image Package header check failed.\n");
151 			result = -ENOENT;
152 		} else {
153 			VERBOSE("FIP header looks OK.\n");
154 		}
155 	}
156 
157 	io_close(backend_handle);
158 
159  fip_dev_init_exit:
160 	return result;
161 }
162 
163 /* Close a connection to the FIP device */
fip_dev_close(io_dev_info_t * dev_info)164 static int fip_dev_close(io_dev_info_t *dev_info)
165 {
166 	/* TODO: Consider tracking open files and cleaning them up here */
167 
168 	/* Clear the backend. */
169 	backend_dev_handle = (uintptr_t)NULL;
170 	backend_image_spec = (uintptr_t)NULL;
171 
172 	return 0;
173 }
174 
175 
176 /* Open a file for access from package. */
fip_file_open(io_dev_info_t * dev_info,const uintptr_t spec,io_entity_t * entity)177 static int fip_file_open(io_dev_info_t *dev_info, const uintptr_t spec,
178 			 io_entity_t *entity)
179 {
180 	int result;
181 	uintptr_t backend_handle;
182 	const io_uuid_spec_t *uuid_spec = (io_uuid_spec_t *)spec;
183 	size_t bytes_read;
184 	int found_file = 0;
185 
186 	assert(uuid_spec != NULL);
187 	assert(entity != NULL);
188 
189 	/* Can only have one file open at a time for the moment. We need to
190 	 * track state like file cursor position. We know the header lives at
191 	 * offset zero, so this entry should never be zero for an active file.
192 	 * When the system supports dynamic memory allocation we can allow more
193 	 * than one open file at a time if needed.
194 	 */
195 	if (current_file.entry.offset_address != 0) {
196 		WARN("fip_file_open : Only one open file at a time.\n");
197 		return -ENOMEM;
198 	}
199 
200 	/* Attempt to access the FIP image */
201 	result = io_open(backend_dev_handle, backend_image_spec,
202 			 &backend_handle);
203 	if (result != 0) {
204 		WARN("Failed to open Firmware Image Package (%i)\n", result);
205 		result = -ENOENT;
206 		goto fip_file_open_exit;
207 	}
208 
209 	/* Seek past the FIP header into the Table of Contents */
210 	result = io_seek(backend_handle, IO_SEEK_SET, sizeof(fip_toc_header_t));
211 	if (result != 0) {
212 		WARN("fip_file_open: failed to seek\n");
213 		result = -ENOENT;
214 		goto fip_file_open_close;
215 	}
216 
217 	found_file = 0;
218 	do {
219 		result = io_read(backend_handle,
220 				 (uintptr_t)&current_file.entry,
221 				 sizeof(current_file.entry),
222 				 &bytes_read);
223 		if (result == 0) {
224 			if (compare_uuids(&current_file.entry.uuid,
225 					  &uuid_spec->uuid) == 0) {
226 				found_file = 1;
227 				break;
228 			}
229 		} else {
230 			WARN("Failed to read FIP (%i)\n", result);
231 			goto fip_file_open_close;
232 		}
233 	} while (compare_uuids(&current_file.entry.uuid, &uuid_null) != 0);
234 
235 	if (found_file == 1) {
236 		/* All fine. Update entity info with file state and return. Set
237 		 * the file position to 0. The 'current_file.entry' holds the
238 		 * base and size of the file.
239 		 */
240 		current_file.file_pos = 0;
241 		entity->info = (uintptr_t)&current_file;
242 	} else {
243 		/* Did not find the file in the FIP. */
244 		current_file.entry.offset_address = 0;
245 		result = -ENOENT;
246 	}
247 
248  fip_file_open_close:
249 	io_close(backend_handle);
250 
251  fip_file_open_exit:
252 	return result;
253 }
254 
255 
256 /* Return the size of a file in package */
fip_file_len(io_entity_t * entity,size_t * length)257 static int fip_file_len(io_entity_t *entity, size_t *length)
258 {
259 	assert(entity != NULL);
260 	assert(length != NULL);
261 
262 	*length =  ((file_state_t *)entity->info)->entry.size;
263 
264 	return 0;
265 }
266 
267 
268 /* Read data from a file in package */
fip_file_read(io_entity_t * entity,uintptr_t buffer,size_t length,size_t * length_read)269 static int fip_file_read(io_entity_t *entity, uintptr_t buffer, size_t length,
270 			  size_t *length_read)
271 {
272 	int result;
273 	file_state_t *fp;
274 	size_t file_offset;
275 	size_t bytes_read;
276 	uintptr_t backend_handle;
277 
278 	assert(entity != NULL);
279 	assert(buffer != (uintptr_t)NULL);
280 	assert(length_read != NULL);
281 	assert(entity->info != (uintptr_t)NULL);
282 
283 	/* Open the backend, attempt to access the blob image */
284 	result = io_open(backend_dev_handle, backend_image_spec,
285 			 &backend_handle);
286 	if (result != 0) {
287 		WARN("Failed to open FIP (%i)\n", result);
288 		result = -ENOENT;
289 		goto fip_file_read_exit;
290 	}
291 
292 	fp = (file_state_t *)entity->info;
293 
294 	/* Seek to the position in the FIP where the payload lives */
295 	file_offset = fp->entry.offset_address + fp->file_pos;
296 	result = io_seek(backend_handle, IO_SEEK_SET, file_offset);
297 	if (result != 0) {
298 		WARN("fip_file_read: failed to seek\n");
299 		result = -ENOENT;
300 		goto fip_file_read_close;
301 	}
302 
303 	result = io_read(backend_handle, buffer, length, &bytes_read);
304 	if (result != 0) {
305 		/* We cannot read our data. Fail. */
306 		WARN("Failed to read payload (%i)\n", result);
307 		result = -ENOENT;
308 		goto fip_file_read_close;
309 	} else {
310 		/* Set caller length and new file position. */
311 		*length_read = bytes_read;
312 		fp->file_pos += bytes_read;
313 	}
314 
315 /* Close the backend. */
316  fip_file_read_close:
317 	io_close(backend_handle);
318 
319  fip_file_read_exit:
320 	return result;
321 }
322 
323 
324 /* Close a file in package */
fip_file_close(io_entity_t * entity)325 static int fip_file_close(io_entity_t *entity)
326 {
327 	/* Clear our current file pointer.
328 	 * If we had malloc() we would free() here.
329 	 */
330 	if (current_file.entry.offset_address != 0) {
331 		zeromem(&current_file, sizeof(current_file));
332 	}
333 
334 	/* Clear the Entity info. */
335 	entity->info = 0;
336 
337 	return 0;
338 }
339 
340 /* Exported functions */
341 
342 /* Register the Firmware Image Package driver with the IO abstraction */
register_io_dev_fip(const io_dev_connector_t ** dev_con)343 int register_io_dev_fip(const io_dev_connector_t **dev_con)
344 {
345 	int result;
346 	assert(dev_con != NULL);
347 
348 	result = io_register_device(&fip_dev_info);
349 	if (result == 0)
350 		*dev_con = &fip_dev_connector;
351 
352 	return result;
353 }
354