1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (c) 2013, Google Inc.
4  * Written by Simon Glass <sjg@chromium.org>
5  *
6  * Perform a grep of an FDT either displaying the source subset or producing
7  * a new .dtb subset which can be used as required.
8  */
9 
10 #include <assert.h>
11 #include <ctype.h>
12 #include <errno.h>
13 #include <getopt.h>
14 #include <fcntl.h>
15 #include <stdbool.h>
16 #include <stdio.h>
17 #include <stdlib.h>
18 #include <string.h>
19 #include <unistd.h>
20 #include <fdt_region.h>
21 
22 #include "fdt_host.h"
23 #include "libfdt_internal.h"
24 
25 /* Define DEBUG to get some debugging output on stderr */
26 #ifdef DEBUG
27 #define debug(a, b...) fprintf(stderr, a, ## b)
28 #else
29 #define debug(a, b...)
30 #endif
31 
32 /* A linked list of values we are grepping for */
33 struct value_node {
34 	int type;		/* Types this value matches (FDT_IS... mask) */
35 	int include;		/* 1 to include matches, 0 to exclude */
36 	const char *string;	/* String to match */
37 	struct value_node *next;	/* Pointer to next node, or NULL */
38 };
39 
40 /* Output formats we support */
41 enum output_t {
42 	OUT_DTS,		/* Device tree source */
43 	OUT_DTB,		/* Valid device tree binary */
44 	OUT_BIN,		/* Fragment of .dtb, for hashing */
45 };
46 
47 /* Holds information which controls our output and options */
48 struct display_info {
49 	enum output_t output;	/* Output format */
50 	int add_aliases;	/* Add aliases node to output */
51 	int all;		/* Display all properties/nodes */
52 	int colour;		/* Display output in ANSI colour */
53 	int region_list;	/* Output a region list */
54 	int flags;		/* Flags (FDT_REG_...) */
55 	int list_strings;	/* List strings in string table */
56 	int show_offset;	/* Show offset */
57 	int show_addr;		/* Show address */
58 	int header;		/* Output an FDT header */
59 	int diff;		/* Show +/- diff markers */
60 	int include_root;	/* Include the root node and all properties */
61 	int remove_strings;	/* Remove unused strings */
62 	int show_dts_version;	/* Put '/dts-v1/;' on the first line */
63 	int types_inc;		/* Mask of types that we include (FDT_IS...) */
64 	int types_exc;		/* Mask of types that we exclude (FDT_IS...) */
65 	int invert;		/* Invert polarity of match */
66 	struct value_node *value_head;	/* List of values to match */
67 	const char *output_fname;	/* Output filename */
68 	FILE *fout;		/* File to write dts/dtb output */
69 };
70 
report_error(const char * where,int err)71 static void report_error(const char *where, int err)
72 {
73 	fprintf(stderr, "Error at '%s': %s\n", where, fdt_strerror(err));
74 }
75 
76 /* Supported ANSI colours */
77 enum {
78 	COL_BLACK,
79 	COL_RED,
80 	COL_GREEN,
81 	COL_YELLOW,
82 	COL_BLUE,
83 	COL_MAGENTA,
84 	COL_CYAN,
85 	COL_WHITE,
86 
87 	COL_NONE = -1,
88 };
89 
90 /**
91  * print_ansi_colour() - Print out the ANSI sequence for a colour
92  *
93  * @fout:	Output file
94  * @col:	Colour to output (COL_...), or COL_NONE to reset colour
95  */
print_ansi_colour(FILE * fout,int col)96 static void print_ansi_colour(FILE *fout, int col)
97 {
98 	if (col == COL_NONE)
99 		fprintf(fout, "\033[0m");
100 	else
101 		fprintf(fout, "\033[1;%dm", col + 30);
102 }
103 
104 
105 /**
106  * value_add() - Add a new value to our list of things to grep for
107  *
108  * @disp:	Display structure, holding info about our options
109  * @headp:	Pointer to header pointer of list
110  * @type:	Type of this value (FDT_IS_...)
111  * @include:	1 if we want to include matches, 0 to exclude
112  * @str:	String value to match
113  */
value_add(struct display_info * disp,struct value_node ** headp,int type,int include,const char * str)114 static int value_add(struct display_info *disp, struct value_node **headp,
115 		     int type, int include, const char *str)
116 {
117 	struct value_node *node;
118 
119 	/*
120 	 * Keep track of which types we are excluding/including. We don't
121 	 * allow both including and excluding things, because it doesn't make
122 	 * sense. 'Including' means that everything not mentioned is
123 	 * excluded. 'Excluding' means that everything not mentioned is
124 	 * included. So using the two together would be meaningless.
125 	 */
126 	if (include)
127 		disp->types_inc |= type;
128 	else
129 		disp->types_exc |= type;
130 	if (disp->types_inc & disp->types_exc & type) {
131 		fprintf(stderr,
132 			"Cannot use both include and exclude for '%s'\n", str);
133 		return -1;
134 	}
135 
136 	str = strdup(str);
137 	if (!str)
138 		goto err_mem;
139 	node = malloc(sizeof(*node));
140 	if (!node)
141 		goto err_mem;
142 	node->next = *headp;
143 	node->type = type;
144 	node->include = include;
145 	node->string = str;
146 	*headp = node;
147 
148 	return 0;
149 err_mem:
150 	fprintf(stderr, "Out of memory\n");
151 	return -1;
152 }
153 
util_is_printable_string(const void * data,int len)154 static bool util_is_printable_string(const void *data, int len)
155 {
156 	const char *s = data;
157 	const char *ss, *se;
158 
159 	/* zero length is not */
160 	if (len == 0)
161 		return 0;
162 
163 	/* must terminate with zero */
164 	if (s[len - 1] != '\0')
165 		return 0;
166 
167 	se = s + len;
168 
169 	while (s < se) {
170 		ss = s;
171 		while (s < se && *s && isprint((unsigned char)*s))
172 			s++;
173 
174 		/* not zero, or not done yet */
175 		if (*s != '\0' || s == ss)
176 			return 0;
177 
178 		s++;
179 	}
180 
181 	return 1;
182 }
183 
utilfdt_print_data(const char * data,int len)184 static void utilfdt_print_data(const char *data, int len)
185 {
186 	int i;
187 	const char *p = data;
188 	const char *s;
189 
190 	/* no data, don't print */
191 	if (len == 0)
192 		return;
193 
194 	if (util_is_printable_string(data, len)) {
195 		printf(" = ");
196 
197 		s = data;
198 		do {
199 			printf("\"%s\"", s);
200 			s += strlen(s) + 1;
201 			if (s < data + len)
202 				printf(", ");
203 		} while (s < data + len);
204 
205 	} else if ((len % 4) == 0) {
206 		const uint32_t *cell = (const uint32_t *)data;
207 
208 		printf(" = <");
209 		for (i = 0, len /= 4; i < len; i++)
210 			printf("0x%08x%s", fdt32_to_cpu(cell[i]),
211 			       i < (len - 1) ? " " : "");
212 		printf(">");
213 	} else {
214 		printf(" = [");
215 		for (i = 0; i < len; i++)
216 			printf("%02x%s", *p++, i < len - 1 ? " " : "");
217 		printf("]");
218 	}
219 }
220 
221 /**
222  * display_fdt_by_regions() - Display regions of an FDT source
223  *
224  * This dumps an FDT as source, but only certain regions of it. This is the
225  * final stage of the grep - we have a list of regions we want to display,
226  * and this function displays them.
227  *
228  * @disp:	Display structure, holding info about our options
229  * @blob:	FDT blob to display
230  * @region:	List of regions to display
231  * @count:	Number of regions
232  */
display_fdt_by_regions(struct display_info * disp,const void * blob,struct fdt_region region[],int count)233 static int display_fdt_by_regions(struct display_info *disp, const void *blob,
234 		struct fdt_region region[], int count)
235 {
236 	struct fdt_region *reg = region, *reg_end = region + count;
237 	uint32_t off_mem_rsvmap = fdt_off_mem_rsvmap(blob);
238 	int base = fdt_off_dt_struct(blob);
239 	int version = fdt_version(blob);
240 	int offset, nextoffset;
241 	int tag, depth, shift;
242 	FILE *f = disp->fout;
243 	uint64_t addr, size;
244 	int in_region;
245 	int file_ofs;
246 	int i;
247 
248 	if (disp->show_dts_version)
249 		fprintf(f, "/dts-v1/;\n");
250 
251 	if (disp->header) {
252 		fprintf(f, "// magic:\t\t0x%x\n", fdt_magic(blob));
253 		fprintf(f, "// totalsize:\t\t0x%x (%d)\n", fdt_totalsize(blob),
254 			fdt_totalsize(blob));
255 		fprintf(f, "// off_dt_struct:\t0x%x\n",
256 			fdt_off_dt_struct(blob));
257 		fprintf(f, "// off_dt_strings:\t0x%x\n",
258 			fdt_off_dt_strings(blob));
259 		fprintf(f, "// off_mem_rsvmap:\t0x%x\n", off_mem_rsvmap);
260 		fprintf(f, "// version:\t\t%d\n", version);
261 		fprintf(f, "// last_comp_version:\t%d\n",
262 			fdt_last_comp_version(blob));
263 		if (version >= 2) {
264 			fprintf(f, "// boot_cpuid_phys:\t0x%x\n",
265 				fdt_boot_cpuid_phys(blob));
266 		}
267 		if (version >= 3) {
268 			fprintf(f, "// size_dt_strings:\t0x%x\n",
269 				fdt_size_dt_strings(blob));
270 		}
271 		if (version >= 17) {
272 			fprintf(f, "// size_dt_struct:\t0x%x\n",
273 				fdt_size_dt_struct(blob));
274 		}
275 		fprintf(f, "\n");
276 	}
277 
278 	if (disp->flags & FDT_REG_ADD_MEM_RSVMAP) {
279 		const struct fdt_reserve_entry *p_rsvmap;
280 
281 		p_rsvmap = (const struct fdt_reserve_entry *)
282 				((const char *)blob + off_mem_rsvmap);
283 		for (i = 0; ; i++) {
284 			addr = fdt64_to_cpu(p_rsvmap[i].address);
285 			size = fdt64_to_cpu(p_rsvmap[i].size);
286 			if (addr == 0 && size == 0)
287 				break;
288 
289 			fprintf(f, "/memreserve/ %llx %llx;\n",
290 				(unsigned long long)addr,
291 				(unsigned long long)size);
292 		}
293 	}
294 
295 	depth = 0;
296 	nextoffset = 0;
297 	shift = 4;	/* 4 spaces per indent */
298 	do {
299 		const struct fdt_property *prop;
300 		const char *name;
301 		int show;
302 		int len;
303 
304 		offset = nextoffset;
305 
306 		/*
307 		 * Work out the file offset of this offset, and decide
308 		 * whether it is in the region list or not
309 		 */
310 		file_ofs = base + offset;
311 		if (reg < reg_end && file_ofs >= reg->offset + reg->size)
312 			reg++;
313 		in_region = reg < reg_end && file_ofs >= reg->offset &&
314 				file_ofs < reg->offset + reg->size;
315 		tag = fdt_next_tag(blob, offset, &nextoffset);
316 
317 		if (tag == FDT_END)
318 			break;
319 		show = in_region || disp->all;
320 		if (show && disp->diff)
321 			fprintf(f, "%c", in_region ? '+' : '-');
322 
323 		if (!show) {
324 			/* Do this here to avoid 'if (show)' in every 'case' */
325 			if (tag == FDT_BEGIN_NODE)
326 				depth++;
327 			else if (tag == FDT_END_NODE)
328 				depth--;
329 			continue;
330 		}
331 		if (tag != FDT_END) {
332 			if (disp->show_addr)
333 				fprintf(f, "%4x: ", file_ofs);
334 			if (disp->show_offset)
335 				fprintf(f, "%4x: ", file_ofs - base);
336 		}
337 
338 		/* Green means included, red means excluded */
339 		if (disp->colour)
340 			print_ansi_colour(f, in_region ? COL_GREEN : COL_RED);
341 
342 		switch (tag) {
343 		case FDT_PROP:
344 			prop = fdt_get_property_by_offset(blob, offset, NULL);
345 			name = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
346 			fprintf(f, "%*s%s", depth * shift, "", name);
347 			utilfdt_print_data(prop->data,
348 					   fdt32_to_cpu(prop->len));
349 			fprintf(f, ";");
350 			break;
351 
352 		case FDT_NOP:
353 			fprintf(f, "%*s// [NOP]", depth * shift, "");
354 			break;
355 
356 		case FDT_BEGIN_NODE:
357 			name = fdt_get_name(blob, offset, &len);
358 			fprintf(f, "%*s%s {", depth++ * shift, "",
359 				*name ? name : "/");
360 			break;
361 
362 		case FDT_END_NODE:
363 			fprintf(f, "%*s};", --depth * shift, "");
364 			break;
365 		}
366 
367 		/* Reset colour back to normal before end of line */
368 		if (disp->colour)
369 			print_ansi_colour(f, COL_NONE);
370 		fprintf(f, "\n");
371 	} while (1);
372 
373 	/* Print a list of strings if requested */
374 	if (disp->list_strings) {
375 		const char *str;
376 		int str_base = fdt_off_dt_strings(blob);
377 
378 		for (offset = 0; offset < fdt_size_dt_strings(blob);
379 				offset += strlen(str) + 1) {
380 			str = fdt_string(blob, offset);
381 			int len = strlen(str) + 1;
382 			int show;
383 
384 			/* Only print strings that are in the region */
385 			file_ofs = str_base + offset;
386 			in_region = reg < reg_end &&
387 					file_ofs >= reg->offset &&
388 					file_ofs + len < reg->offset +
389 						reg->size;
390 			show = in_region || disp->all;
391 			if (show && disp->diff)
392 				printf("%c", in_region ? '+' : '-');
393 			if (disp->show_addr)
394 				printf("%4x: ", file_ofs);
395 			if (disp->show_offset)
396 				printf("%4x: ", offset);
397 			printf("%s\n", str);
398 		}
399 	}
400 
401 	return 0;
402 }
403 
404 /**
405  * dump_fdt_regions() - Dump regions of an FDT as binary data
406  *
407  * This dumps an FDT as binary, but only certain regions of it. This is the
408  * final stage of the grep - we have a list of regions we want to dump,
409  * and this function dumps them.
410  *
411  * The output of this function may or may not be a valid FDT. To ensure it
412  * is, these disp->flags must be set:
413  *
414  *   FDT_REG_SUPERNODES: ensures that subnodes are preceded by their
415  *		parents. Without this option, fragments of subnode data may be
416  *		output without the supernodes above them. This is useful for
417  *		hashing but cannot produce a valid FDT.
418  *   FDT_REG_ADD_STRING_TAB: Adds a string table to the end of the FDT.
419  *		Without this none of the properties will have names
420  *   FDT_REG_ADD_MEM_RSVMAP: Adds a mem_rsvmap table - an FDT is invalid
421  *		without this.
422  *
423  * @disp:	Display structure, holding info about our options
424  * @blob:	FDT blob to display
425  * @region:	List of regions to display
426  * @count:	Number of regions
427  * @out:	Output destination
428  */
dump_fdt_regions(struct display_info * disp,const void * blob,struct fdt_region region[],int count,char * out)429 static int dump_fdt_regions(struct display_info *disp, const void *blob,
430 		struct fdt_region region[], int count, char *out)
431 {
432 	struct fdt_header *fdt;
433 	int size, struct_start;
434 	int ptr;
435 	int i;
436 
437 	/* Set up a basic header (even if we don't actually write it) */
438 	fdt = (struct fdt_header *)out;
439 	memset(fdt, '\0', sizeof(*fdt));
440 	fdt_set_magic(fdt, FDT_MAGIC);
441 	struct_start = FDT_ALIGN(sizeof(struct fdt_header),
442 					sizeof(struct fdt_reserve_entry));
443 	fdt_set_off_mem_rsvmap(fdt, struct_start);
444 	fdt_set_version(fdt, FDT_LAST_SUPPORTED_VERSION);
445 	fdt_set_last_comp_version(fdt, FDT_FIRST_SUPPORTED_VERSION);
446 
447 	/*
448 	 * Calculate the total size of the regions we are writing out. The
449 	 * first will be the mem_rsvmap if the FDT_REG_ADD_MEM_RSVMAP flag
450 	 * is set. The last will be the string table if FDT_REG_ADD_STRING_TAB
451 	 * is set.
452 	 */
453 	for (i = size = 0; i < count; i++)
454 		size += region[i].size;
455 
456 	/* Bring in the mem_rsvmap section from the old file if requested */
457 	if (count > 0 && (disp->flags & FDT_REG_ADD_MEM_RSVMAP)) {
458 		struct_start += region[0].size;
459 		size -= region[0].size;
460 	}
461 	fdt_set_off_dt_struct(fdt, struct_start);
462 
463 	/* Update the header to have the correct offsets/sizes */
464 	if (count >= 2 && (disp->flags & FDT_REG_ADD_STRING_TAB)) {
465 		int str_size;
466 
467 		str_size = region[count - 1].size;
468 		fdt_set_size_dt_struct(fdt, size - str_size);
469 		fdt_set_off_dt_strings(fdt, struct_start + size - str_size);
470 		fdt_set_size_dt_strings(fdt, str_size);
471 		fdt_set_totalsize(fdt, struct_start + size);
472 	}
473 
474 	/* Write the header if required */
475 	ptr = 0;
476 	if (disp->header) {
477 		ptr = sizeof(*fdt);
478 		while (ptr < fdt_off_mem_rsvmap(fdt))
479 			out[ptr++] = '\0';
480 	}
481 
482 	/* Output all the nodes including any mem_rsvmap/string table */
483 	for (i = 0; i < count; i++) {
484 		struct fdt_region *reg = &region[i];
485 
486 		memcpy(out + ptr, (const char *)blob + reg->offset, reg->size);
487 		ptr += reg->size;
488 	}
489 
490 	return ptr;
491 }
492 
493 /**
494  * show_region_list() - Print out a list of regions
495  *
496  * The list includes the region offset (absolute offset from start of FDT
497  * blob in bytes) and size
498  *
499  * @reg:	List of regions to print
500  * @count:	Number of regions
501  */
show_region_list(struct fdt_region * reg,int count)502 static void show_region_list(struct fdt_region *reg, int count)
503 {
504 	int i;
505 
506 	printf("Regions: %d\n", count);
507 	for (i = 0; i < count; i++, reg++) {
508 		printf("%d:  %-10x  %-10x\n", i, reg->offset,
509 		       reg->offset + reg->size);
510 	}
511 }
512 
check_type_include(void * priv,int type,const char * data,int size)513 static int check_type_include(void *priv, int type, const char *data, int size)
514 {
515 	struct display_info *disp = priv;
516 	struct value_node *val;
517 	int match, none_match = FDT_IS_ANY;
518 
519 	/* If none of our conditions mention this type, we know nothing */
520 	debug("type=%x, data=%s\n", type, data ? data : "(null)");
521 	if (!((disp->types_inc | disp->types_exc) & type)) {
522 		debug("   - not in any condition\n");
523 		return -1;
524 	}
525 
526 	/*
527 	 * Go through the list of conditions. For inclusive conditions, we
528 	 * return 1 at the first match. For exclusive conditions, we must
529 	 * check that there are no matches.
530 	 */
531 	if (data) {
532 		for (val = disp->value_head; val; val = val->next) {
533 			if (!(type & val->type))
534 				continue;
535 			match = fdt_stringlist_contains(data, size,
536 							val->string);
537 			debug("      - val->type=%x, str='%s', match=%d\n",
538 			      val->type, val->string, match);
539 			if (match && val->include) {
540 				debug("   - match inc %s\n", val->string);
541 				return 1;
542 			}
543 			if (match)
544 				none_match &= ~val->type;
545 		}
546 	}
547 
548 	/*
549 	 * If this is an exclusive condition, and nothing matches, then we
550 	 * should return 1.
551 	 */
552 	if ((type & disp->types_exc) && (none_match & type)) {
553 		debug("   - match exc\n");
554 		/*
555 		 * Allow FDT_IS_COMPAT to make the final decision in the
556 		 * case where there is no specific type
557 		 */
558 		if (type == FDT_IS_NODE && disp->types_exc == FDT_ANY_GLOBAL) {
559 			debug("   - supressed exc node\n");
560 			return -1;
561 		}
562 		return 1;
563 	}
564 
565 	/*
566 	 * Allow FDT_IS_COMPAT to make the final decision in the
567 	 * case where there is no specific type (inclusive)
568 	 */
569 	if (type == FDT_IS_NODE && disp->types_inc == FDT_ANY_GLOBAL)
570 		return -1;
571 
572 	debug("   - no match, types_inc=%x, types_exc=%x, none_match=%x\n",
573 	      disp->types_inc, disp->types_exc, none_match);
574 
575 	return 0;
576 }
577 
578 /**
579  * h_include() - Include handler function for fdt_find_regions()
580  *
581  * This function decides whether to include or exclude a node, property or
582  * compatible string. The function is defined by fdt_find_regions().
583  *
584  * The algorithm is documented in the code - disp->invert is 0 for normal
585  * operation, and 1 to invert the sense of all matches.
586  *
587  * See
588  */
h_include(void * priv,const void * fdt,int offset,int type,const char * data,int size)589 static int h_include(void *priv, const void *fdt, int offset, int type,
590 		     const char *data, int size)
591 {
592 	struct display_info *disp = priv;
593 	int inc, len;
594 
595 	inc = check_type_include(priv, type, data, size);
596 	if (disp->include_root && type == FDT_IS_PROP && offset == 0 && inc)
597 		return 1;
598 
599 	/*
600 	 * If the node name does not tell us anything, check the
601 	 * compatible string
602 	 */
603 	if (inc == -1 && type == FDT_IS_NODE) {
604 		debug("   - checking compatible2\n");
605 		data = fdt_getprop(fdt, offset, "compatible", &len);
606 		inc = check_type_include(priv, FDT_IS_COMPAT, data, len);
607 	}
608 
609 	/* If we still have no idea, check for properties in the node */
610 	if (inc != 1 && type == FDT_IS_NODE &&
611 	    (disp->types_inc & FDT_NODE_HAS_PROP)) {
612 		debug("   - checking node '%s'\n",
613 		      fdt_get_name(fdt, offset, NULL));
614 		for (offset = fdt_first_property_offset(fdt, offset);
615 		     offset > 0 && inc != 1;
616 		     offset = fdt_next_property_offset(fdt, offset)) {
617 			const struct fdt_property *prop;
618 			const char *str;
619 
620 			prop = fdt_get_property_by_offset(fdt, offset, NULL);
621 			if (!prop)
622 				continue;
623 			str = fdt_string(fdt, fdt32_to_cpu(prop->nameoff));
624 			inc = check_type_include(priv, FDT_NODE_HAS_PROP, str,
625 						 strlen(str));
626 		}
627 		if (inc == -1)
628 			inc = 0;
629 	}
630 
631 	switch (inc) {
632 	case 1:
633 		inc = !disp->invert;
634 		break;
635 	case 0:
636 		inc = disp->invert;
637 		break;
638 	}
639 	debug("   - returning %d\n", inc);
640 
641 	return inc;
642 }
643 
h_cmp_region(const void * v1,const void * v2)644 static int h_cmp_region(const void *v1, const void *v2)
645 {
646 	const struct fdt_region *region1 = v1, *region2 = v2;
647 
648 	return region1->offset - region2->offset;
649 }
650 
fdtgrep_find_regions(const void * fdt,int (* include_func)(void * priv,const void * fdt,int offset,int type,const char * data,int size),struct display_info * disp,struct fdt_region * region,int max_regions,char * path,int path_len,int flags)651 static int fdtgrep_find_regions(const void *fdt,
652 		int (*include_func)(void *priv, const void *fdt, int offset,
653 				 int type, const char *data, int size),
654 		struct display_info *disp, struct fdt_region *region,
655 		int max_regions, char *path, int path_len, int flags)
656 {
657 	struct fdt_region_state state;
658 	int count;
659 	int ret;
660 
661 	count = 0;
662 	ret = fdt_first_region(fdt, include_func, disp,
663 			&region[count++], path, path_len,
664 			disp->flags, &state);
665 	while (ret == 0) {
666 		ret = fdt_next_region(fdt, include_func, disp,
667 				count < max_regions ? &region[count] : NULL,
668 				path, path_len, disp->flags, &state);
669 		if (!ret)
670 			count++;
671 	}
672 	if (ret && ret != -FDT_ERR_NOTFOUND)
673 		return ret;
674 
675 	/* Find all the aliases and add those regions back in */
676 	if (disp->add_aliases && count < max_regions) {
677 		int new_count;
678 
679 		new_count = fdt_add_alias_regions(fdt, region, count,
680 						  max_regions, &state);
681 		if (new_count == -FDT_ERR_NOTFOUND) {
682 			/* No alias node found */
683 		} else if (new_count < 0) {
684 			return new_count;
685 		} else if (new_count <= max_regions) {
686 			/*
687 			* The alias regions will now be at the end of the list.
688 			* Sort the regions by offset to get things into the
689 			* right order
690 			*/
691 			count = new_count;
692 			qsort(region, count, sizeof(struct fdt_region),
693 			      h_cmp_region);
694 		}
695 	}
696 
697 	return count;
698 }
699 
utilfdt_read_err_len(const char * filename,char ** buffp,off_t * len)700 int utilfdt_read_err_len(const char *filename, char **buffp, off_t *len)
701 {
702 	int fd = 0;	/* assume stdin */
703 	char *buf = NULL;
704 	off_t bufsize = 1024, offset = 0;
705 	int ret = 0;
706 
707 	*buffp = NULL;
708 	if (strcmp(filename, "-") != 0) {
709 		fd = open(filename, O_RDONLY);
710 		if (fd < 0)
711 			return errno;
712 	}
713 
714 	/* Loop until we have read everything */
715 	buf = malloc(bufsize);
716 	if (!buf)
717 		return -ENOMEM;
718 	do {
719 		/* Expand the buffer to hold the next chunk */
720 		if (offset == bufsize) {
721 			bufsize *= 2;
722 			buf = realloc(buf, bufsize);
723 			if (!buf)
724 				return -ENOMEM;
725 		}
726 
727 		ret = read(fd, &buf[offset], bufsize - offset);
728 		if (ret < 0) {
729 			ret = errno;
730 			break;
731 		}
732 		offset += ret;
733 	} while (ret != 0);
734 
735 	/* Clean up, including closing stdin; return errno on error */
736 	close(fd);
737 	if (ret)
738 		free(buf);
739 	else
740 		*buffp = buf;
741 	*len = bufsize;
742 	return ret;
743 }
744 
utilfdt_read_err(const char * filename,char ** buffp)745 int utilfdt_read_err(const char *filename, char **buffp)
746 {
747 	off_t len;
748 	return utilfdt_read_err_len(filename, buffp, &len);
749 }
750 
utilfdt_read_len(const char * filename,off_t * len)751 char *utilfdt_read_len(const char *filename, off_t *len)
752 {
753 	char *buff;
754 	int ret = utilfdt_read_err_len(filename, &buff, len);
755 
756 	if (ret) {
757 		fprintf(stderr, "Couldn't open blob from '%s': %s\n", filename,
758 			strerror(ret));
759 		return NULL;
760 	}
761 	/* Successful read */
762 	return buff;
763 }
764 
utilfdt_read(const char * filename)765 char *utilfdt_read(const char *filename)
766 {
767 	off_t len;
768 	return utilfdt_read_len(filename, &len);
769 }
770 
771 /**
772  * Run the main fdtgrep operation, given a filename and valid arguments
773  *
774  * @param disp		Display information / options
775  * @param filename	Filename of blob file
776  * @param return 0 if ok, -ve on error
777  */
do_fdtgrep(struct display_info * disp,const char * filename)778 static int do_fdtgrep(struct display_info *disp, const char *filename)
779 {
780 	struct fdt_region *region = NULL;
781 	int max_regions;
782 	int count = 100;
783 	char path[1024];
784 	char *blob;
785 	int i, ret;
786 
787 	blob = utilfdt_read(filename);
788 	if (!blob)
789 		return -1;
790 	ret = fdt_check_header(blob);
791 	if (ret) {
792 		fprintf(stderr, "Error: %s\n", fdt_strerror(ret));
793 		return ret;
794 	}
795 
796 	/* Allow old files, but they are untested */
797 	if (fdt_version(blob) < 17 && disp->value_head) {
798 		fprintf(stderr,
799 			"Warning: fdtgrep does not fully support version %d files\n",
800 			fdt_version(blob));
801 	}
802 
803 	/*
804 	 * We do two passes, since we don't know how many regions we need.
805 	 * The first pass will count the regions, but if it is too many,
806 	 * we do another pass to actually record them.
807 	 */
808 	for (i = 0; i < 2; i++) {
809 		region = realloc(region, count * sizeof(struct fdt_region));
810 		if (!region) {
811 			fprintf(stderr, "Out of memory for %d regions\n",
812 				count);
813 			return -1;
814 		}
815 		max_regions = count;
816 		count = fdtgrep_find_regions(blob,
817 				h_include, disp,
818 				region, max_regions, path, sizeof(path),
819 				disp->flags);
820 		if (count < 0) {
821 			report_error("fdt_find_regions", count);
822 			free(region);
823 			return -1;
824 		}
825 		if (count <= max_regions)
826 			break;
827 	}
828 	if (count > max_regions) {
829 		free(region);
830 		fprintf(stderr, "Internal error with fdtgrep_find_region()\n");
831 		return -1;
832 	}
833 
834 	/* Optionally print a list of regions */
835 	if (disp->region_list)
836 		show_region_list(region, count);
837 
838 	/* Output either source .dts or binary .dtb */
839 	if (disp->output == OUT_DTS) {
840 		ret = display_fdt_by_regions(disp, blob, region, count);
841 	} else {
842 		void *fdt;
843 		/* Allow reserved memory section to expand slightly */
844 		int size = fdt_totalsize(blob) + 16;
845 
846 		fdt = malloc(size);
847 		if (!fdt) {
848 			fprintf(stderr, "Out_of_memory\n");
849 			ret = -1;
850 			goto err;
851 		}
852 		size = dump_fdt_regions(disp, blob, region, count, fdt);
853 		if (disp->remove_strings) {
854 			void *out;
855 
856 			out = malloc(size);
857 			if (!out) {
858 				fprintf(stderr, "Out_of_memory\n");
859 				ret = -1;
860 				goto err;
861 			}
862 			ret = fdt_remove_unused_strings(fdt, out);
863 			if (ret < 0) {
864 				fprintf(stderr,
865 					"Failed to remove unused strings: err=%d\n",
866 					ret);
867 				goto err;
868 			}
869 			free(fdt);
870 			fdt = out;
871 			ret = fdt_pack(fdt);
872 			if (ret < 0) {
873 				fprintf(stderr, "Failed to pack: err=%d\n",
874 					ret);
875 				goto err;
876 			}
877 			size = fdt_totalsize(fdt);
878 		}
879 
880 		if (size != fwrite(fdt, 1, size, disp->fout)) {
881 			fprintf(stderr, "Write failure, %d bytes\n", size);
882 			free(fdt);
883 			ret = 1;
884 			goto err;
885 		}
886 		free(fdt);
887 	}
888 err:
889 	free(blob);
890 	free(region);
891 
892 	return ret;
893 }
894 
895 static const char usage_synopsis[] =
896 	"fdtgrep - extract portions from device tree\n"
897 	"\n"
898 	"Usage:\n"
899 	"	fdtgrep <options> <dt file>|-\n\n"
900 	"Output formats are:\n"
901 	"\tdts - device tree soure text\n"
902 	"\tdtb - device tree blob (sets -Hmt automatically)\n"
903 	"\tbin - device tree fragment (may not be a valid .dtb)";
904 
905 /* Helper for usage_short_opts string constant */
906 #define USAGE_COMMON_SHORT_OPTS "hV"
907 
908 /* Helper for aligning long_opts array */
909 #define a_argument required_argument
910 
911 /* Helper for usage_long_opts option array */
912 #define USAGE_COMMON_LONG_OPTS \
913 	{"help",      no_argument, NULL, 'h'}, \
914 	{"version",   no_argument, NULL, 'V'}, \
915 	{NULL,        no_argument, NULL, 0x0}
916 
917 /* Helper for usage_opts_help array */
918 #define USAGE_COMMON_OPTS_HELP \
919 	"Print this help and exit", \
920 	"Print version and exit", \
921 	NULL
922 
923 /* Helper for getopt case statements */
924 #define case_USAGE_COMMON_FLAGS \
925 	case 'h': usage(NULL); \
926 	/* fallthrough */ \
927 	case 'V': util_version(); \
928 	/* fallthrough */ \
929 	case '?': usage("unknown option");
930 
931 static const char usage_short_opts[] =
932 		"haAc:b:C:defg:G:HIlLmn:N:o:O:p:P:rRsStTv"
933 		USAGE_COMMON_SHORT_OPTS;
934 static struct option const usage_long_opts[] = {
935 	{"show-address",	no_argument, NULL, 'a'},
936 	{"colour",		no_argument, NULL, 'A'},
937 	{"include-node-with-prop", a_argument, NULL, 'b'},
938 	{"include-compat",	a_argument, NULL, 'c'},
939 	{"exclude-compat",	a_argument, NULL, 'C'},
940 	{"diff",		no_argument, NULL, 'd'},
941 	{"enter-node",		no_argument, NULL, 'e'},
942 	{"show-offset",		no_argument, NULL, 'f'},
943 	{"include-match",	a_argument, NULL, 'g'},
944 	{"exclude-match",	a_argument, NULL, 'G'},
945 	{"show-header",		no_argument, NULL, 'H'},
946 	{"show-version",	no_argument, NULL, 'I'},
947 	{"list-regions",	no_argument, NULL, 'l'},
948 	{"list-strings",	no_argument, NULL, 'L'},
949 	{"include-mem",		no_argument, NULL, 'm'},
950 	{"include-node",	a_argument, NULL, 'n'},
951 	{"exclude-node",	a_argument, NULL, 'N'},
952 	{"include-prop",	a_argument, NULL, 'p'},
953 	{"exclude-prop",	a_argument, NULL, 'P'},
954 	{"remove-strings",	no_argument, NULL, 'r'},
955 	{"include-root",	no_argument, NULL, 'R'},
956 	{"show-subnodes",	no_argument, NULL, 's'},
957 	{"skip-supernodes",	no_argument, NULL, 'S'},
958 	{"show-stringtab",	no_argument, NULL, 't'},
959 	{"show-aliases",	no_argument, NULL, 'T'},
960 	{"out",			a_argument, NULL, 'o'},
961 	{"out-format",		a_argument, NULL, 'O'},
962 	{"invert-match",	no_argument, NULL, 'v'},
963 	USAGE_COMMON_LONG_OPTS,
964 };
965 static const char * const usage_opts_help[] = {
966 	"Display address",
967 	"Show all nodes/tags, colour those that match",
968 	"Include contains containing property",
969 	"Compatible nodes to include in grep",
970 	"Compatible nodes to exclude in grep",
971 	"Diff: Mark matching nodes with +, others with -",
972 	"Enter direct subnode names of matching nodes",
973 	"Display offset",
974 	"Node/property/compatible string to include in grep",
975 	"Node/property/compatible string to exclude in grep",
976 	"Output a header",
977 	"Put \"/dts-v1/;\" on first line of dts output",
978 	"Output a region list",
979 	"List strings in string table",
980 	"Include mem_rsvmap section in binary output",
981 	"Node to include in grep",
982 	"Node to exclude in grep",
983 	"Property to include in grep",
984 	"Property to exclude in grep",
985 	"Remove unused strings from string table",
986 	"Include root node and all properties",
987 	"Show all subnodes matching nodes",
988 	"Don't include supernodes of matching nodes",
989 	"Include string table in binary output",
990 	"Include matching aliases in output",
991 	"-o <output file>",
992 	"-O <output format>",
993 	"Invert the sense of matching (select non-matching lines)",
994 	USAGE_COMMON_OPTS_HELP
995 };
996 
997 /**
998  * Call getopt_long() with standard options
999  *
1000  * Since all util code runs getopt in the same way, provide a helper.
1001  */
1002 #define util_getopt_long() getopt_long(argc, argv, usage_short_opts, \
1003 				       usage_long_opts, NULL)
1004 
util_usage(const char * errmsg,const char * synopsis,const char * short_opts,struct option const long_opts[],const char * const opts_help[])1005 void util_usage(const char *errmsg, const char *synopsis,
1006 		const char *short_opts, struct option const long_opts[],
1007 		const char * const opts_help[])
1008 {
1009 	FILE *fp = errmsg ? stderr : stdout;
1010 	const char a_arg[] = "<arg>";
1011 	size_t a_arg_len = strlen(a_arg) + 1;
1012 	size_t i;
1013 	int optlen;
1014 
1015 	fprintf(fp,
1016 		"Usage: %s\n"
1017 		"\n"
1018 		"Options: -[%s]\n", synopsis, short_opts);
1019 
1020 	/* prescan the --long opt length to auto-align */
1021 	optlen = 0;
1022 	for (i = 0; long_opts[i].name; ++i) {
1023 		/* +1 is for space between --opt and help text */
1024 		int l = strlen(long_opts[i].name) + 1;
1025 		if (long_opts[i].has_arg == a_argument)
1026 			l += a_arg_len;
1027 		if (optlen < l)
1028 			optlen = l;
1029 	}
1030 
1031 	for (i = 0; long_opts[i].name; ++i) {
1032 		/* helps when adding new applets or options */
1033 		assert(opts_help[i] != NULL);
1034 
1035 		/* first output the short flag if it has one */
1036 		if (long_opts[i].val > '~')
1037 			fprintf(fp, "      ");
1038 		else
1039 			fprintf(fp, "  -%c, ", long_opts[i].val);
1040 
1041 		/* then the long flag */
1042 		if (long_opts[i].has_arg == no_argument) {
1043 			fprintf(fp, "--%-*s", optlen, long_opts[i].name);
1044 		} else {
1045 			fprintf(fp, "--%s %s%*s", long_opts[i].name, a_arg,
1046 				(int)(optlen - strlen(long_opts[i].name) -
1047 				a_arg_len), "");
1048 		}
1049 
1050 		/* finally the help text */
1051 		fprintf(fp, "%s\n", opts_help[i]);
1052 	}
1053 
1054 	if (errmsg) {
1055 		fprintf(fp, "\nError: %s\n", errmsg);
1056 		exit(EXIT_FAILURE);
1057 	} else {
1058 		exit(EXIT_SUCCESS);
1059 	}
1060 }
1061 
1062 /**
1063  * Show usage and exit
1064  *
1065  * If you name all your usage variables with usage_xxx, then you can call this
1066  * help macro rather than expanding all arguments yourself.
1067  *
1068  * @param errmsg	If non-NULL, an error message to display
1069  */
1070 #define usage(errmsg) \
1071 	util_usage(errmsg, usage_synopsis, usage_short_opts, \
1072 		   usage_long_opts, usage_opts_help)
1073 
util_version(void)1074 void util_version(void)
1075 {
1076 	printf("Version: %s\n", "(U-Boot)");
1077 	exit(0);
1078 }
1079 
scan_args(struct display_info * disp,int argc,char * argv[])1080 static void scan_args(struct display_info *disp, int argc, char *argv[])
1081 {
1082 	int opt;
1083 
1084 	while ((opt = util_getopt_long()) != EOF) {
1085 		int type = 0;
1086 		int inc = 1;
1087 
1088 		switch (opt) {
1089 		case_USAGE_COMMON_FLAGS
1090 		/* fallthrough */
1091 		case 'a':
1092 			disp->show_addr = 1;
1093 			break;
1094 		case 'A':
1095 			disp->all = 1;
1096 			break;
1097 		case 'b':
1098 			type = FDT_NODE_HAS_PROP;
1099 			break;
1100 		case 'C':
1101 			inc = 0;
1102 			/* fallthrough */
1103 		case 'c':
1104 			type = FDT_IS_COMPAT;
1105 			break;
1106 		case 'd':
1107 			disp->diff = 1;
1108 			break;
1109 		case 'e':
1110 			disp->flags |= FDT_REG_DIRECT_SUBNODES;
1111 			break;
1112 		case 'f':
1113 			disp->show_offset = 1;
1114 			break;
1115 		case 'G':
1116 			inc = 0;
1117 			/* fallthrough */
1118 		case 'g':
1119 			type = FDT_ANY_GLOBAL;
1120 			break;
1121 		case 'H':
1122 			disp->header = 1;
1123 			break;
1124 		case 'l':
1125 			disp->region_list = 1;
1126 			break;
1127 		case 'L':
1128 			disp->list_strings = 1;
1129 			break;
1130 		case 'm':
1131 			disp->flags |= FDT_REG_ADD_MEM_RSVMAP;
1132 			break;
1133 		case 'N':
1134 			inc = 0;
1135 			/* fallthrough */
1136 		case 'n':
1137 			type = FDT_IS_NODE;
1138 			break;
1139 		case 'o':
1140 			disp->output_fname = optarg;
1141 			break;
1142 		case 'O':
1143 			if (!strcmp(optarg, "dtb"))
1144 				disp->output = OUT_DTB;
1145 			else if (!strcmp(optarg, "dts"))
1146 				disp->output = OUT_DTS;
1147 			else if (!strcmp(optarg, "bin"))
1148 				disp->output = OUT_BIN;
1149 			else
1150 				usage("Unknown output format");
1151 			break;
1152 		case 'P':
1153 			inc = 0;
1154 			/* fallthrough */
1155 		case 'p':
1156 			type = FDT_IS_PROP;
1157 			break;
1158 		case 'r':
1159 			disp->remove_strings = 1;
1160 			break;
1161 		case 'R':
1162 			disp->include_root = 1;
1163 			break;
1164 		case 's':
1165 			disp->flags |= FDT_REG_ALL_SUBNODES;
1166 			break;
1167 		case 'S':
1168 			disp->flags &= ~FDT_REG_SUPERNODES;
1169 			break;
1170 		case 't':
1171 			disp->flags |= FDT_REG_ADD_STRING_TAB;
1172 			break;
1173 		case 'T':
1174 			disp->add_aliases = 1;
1175 			break;
1176 		case 'v':
1177 			disp->invert = 1;
1178 			break;
1179 		case 'I':
1180 			disp->show_dts_version = 1;
1181 			break;
1182 		}
1183 
1184 		if (type && value_add(disp, &disp->value_head, type, inc,
1185 				      optarg))
1186 			usage("Cannot add value");
1187 	}
1188 
1189 	if (disp->invert && disp->types_exc)
1190 		usage("-v has no meaning when used with 'exclude' conditions");
1191 }
1192 
main(int argc,char * argv[])1193 int main(int argc, char *argv[])
1194 {
1195 	char *filename = NULL;
1196 	struct display_info disp;
1197 	int ret;
1198 
1199 	/* set defaults */
1200 	memset(&disp, '\0', sizeof(disp));
1201 	disp.flags = FDT_REG_SUPERNODES;	/* Default flags */
1202 
1203 	scan_args(&disp, argc, argv);
1204 
1205 	/* Show matched lines in colour if we can */
1206 	disp.colour = disp.all && isatty(0);
1207 
1208 	/* Any additional arguments can match anything, just like -g */
1209 	while (optind < argc - 1) {
1210 		if (value_add(&disp, &disp.value_head, FDT_IS_ANY, 1,
1211 			      argv[optind++]))
1212 			usage("Cannot add value");
1213 	}
1214 
1215 	if (optind < argc)
1216 		filename = argv[optind++];
1217 	if (!filename)
1218 		usage("Missing filename");
1219 
1220 	/* If a valid .dtb is required, set flags to ensure we get one */
1221 	if (disp.output == OUT_DTB) {
1222 		disp.header = 1;
1223 		disp.flags |= FDT_REG_ADD_MEM_RSVMAP | FDT_REG_ADD_STRING_TAB;
1224 	}
1225 
1226 	if (disp.output_fname) {
1227 		disp.fout = fopen(disp.output_fname, "w");
1228 		if (!disp.fout)
1229 			usage("Cannot open output file");
1230 	} else {
1231 		disp.fout = stdout;
1232 	}
1233 
1234 	/* Run the grep and output the results */
1235 	ret = do_fdtgrep(&disp, filename);
1236 	if (disp.output_fname)
1237 		fclose(disp.fout);
1238 	if (ret)
1239 		return 1;
1240 
1241 	return 0;
1242 }
1243