1/*
2 * imagetag.c
3 *
4 * Copyright (C) 2005 Mike Baker
5 * Copyright (C) 2008 Felix Fietkau <nbd@nbd.name>
6 * Copyrigth (C) 2010 Daniel Dickinson <openwrt@cshore.neomailbox.net>
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * as published by the Free Software Foundation; either version 2
11 * of the License, or (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
21 */
22
23#include <stdio.h>
24#include <stdlib.h>
25#include <stddef.h>
26#include <unistd.h>
27#include <fcntl.h>
28#include <sys/mman.h>
29#include <sys/stat.h>
30#include <string.h>
31#include <errno.h>
32
33#include <sys/ioctl.h>
34#include <mtd/mtd-user.h>
35
36#include "mtd.h"
37#include "crc32.h"
38
39#define TAGVER_LEN		4	/* Length of Tag Version */
40#define TAGLAYOUT_LEN		4	/* Length of FlashLayoutVer */
41#define SIG1_LEN		20	/* Company Signature 1 Length */
42#define SIG2_LEN		14	/* Company Signature 2 Length */
43#define BOARDID_LEN		16	/* Length of BoardId */
44#define ENDIANFLAG_LEN		2	/* Endian Flag Length */
45#define CHIPID_LEN		6	/* Chip Id Length */
46#define IMAGE_LEN		10	/* Length of Length Field */
47#define ADDRESS_LEN		12	/* Length of Address field */
48#define DUALFLAG_LEN		2	/* Dual Image flag Length */
49#define INACTIVEFLAG_LEN	2	/* Inactie Flag Length */
50#define RSASIG_LEN		20	/* Length of RSA Signature in tag */
51#define TAGINFO1_LEN		30	/* Length of vendor information field1 in tag */
52#define FLASHLAYOUTVER_LEN	4	/* Length of Flash Layout Version String tag */
53#define TAGINFO2_LEN		16	/* Length of vendor information field2 in tag */
54#define ALTTAGINFO_LEN		54	/* Alternate length for vendor information; Pirelli */
55
56#define NUM_PIRELLI		2
57#define IMAGETAG_CRC_START	0xFFFFFFFF
58
59#define PIRELLI_BOARDS { \
60	"AGPF-S0", \
61	"DWV-S0", \
62}
63/*
64 * The broadcom firmware assumes the rootfs starts the image,
65 * therefore uses the rootfs start (flash_image_address)
66 * to determine where to flash the image.  Since we have the kernel first
67 * we have to give it the kernel address, but the crc uses the length
68 * associated with this address (root_length), which is added to the kernel
69 * length (kernel_length) to determine the length of image to flash and thus
70 * needs to be rootfs + deadcode (jffs2 EOF marker)
71*/
72
73struct bcm_tag {
74	/* 0-3: Version of the image tag */
75	char tag_version[TAGVER_LEN];
76	/* 4-23: Company Line 1 */
77	char sig_1[SIG1_LEN];
78	/*  24-37: Company Line 2 */
79	char sig_2[SIG2_LEN];
80	/* 38-43: Chip this image is for */
81	char chip_id[CHIPID_LEN];
82	/* 44-59: Board name */
83	char board_id[BOARDID_LEN];
84	/* 60-61: Map endianness -- 1 BE 0 LE */
85	char big_endian[ENDIANFLAG_LEN];
86	/* 62-71: Total length of image */
87	char total_length[IMAGE_LEN];
88	/* 72-83: Address in memory of CFE */
89	char cfe__address[ADDRESS_LEN];
90	/* 84-93: Size of CFE */
91	char cfe_length[IMAGE_LEN];
92	/* 94-105: Address in memory of image start
93	 * (kernel for OpenWRT, rootfs for stock firmware)
94	 */
95	char flash_image_start[ADDRESS_LEN];
96	/* 106-115: Size of rootfs */
97	char root_length[IMAGE_LEN];
98	/* 116-127: Address in memory of kernel */
99	char kernel_address[ADDRESS_LEN];
100	/* 128-137: Size of kernel */
101	char kernel_length[IMAGE_LEN];
102	/* 138-139: Unused at the moment */
103	char dual_image[DUALFLAG_LEN];
104	/* 140-141: Unused at the moment */
105	char inactive_flag[INACTIVEFLAG_LEN];
106	/* 142-161: RSA Signature (not used; some vendors may use this) */
107	char rsa_signature[RSASIG_LEN];
108	/* 162-191: Compilation and related information (not used in OpenWrt) */
109	char information1[TAGINFO1_LEN];
110	/* 192-195: Version flash layout */
111	char flash_layout_ver[FLASHLAYOUTVER_LEN];
112	/* 196-199: kernel+rootfs CRC32 */
113	__u32 fskernel_crc;
114	/* 200-215: Unused except on Alice Gate where is is information */
115	char information2[TAGINFO2_LEN];
116	/* 216-219: CRC32 of image less imagetag (kernel for Alice Gate) */
117	__u32 image_crc;
118	/* 220-223: CRC32 of rootfs partition */
119	__u32 rootfs_crc;
120	/* 224-227: CRC32 of kernel partition */
121	__u32 kernel_crc;
122	/* 228-231: Image sequence number */
123	char image_sequence[4];
124	/* 222-235: Openwrt: real rootfs length */
125	__u32 real_rootfs_length;
126	/* 236-239: CRC32 of header excluding last 20 bytes */
127	__u32 header_crc;
128	/* 240-255: Unused at present */
129	char reserved2[16];
130};
131ssize_t pread(int fd, void *buf, size_t count, off_t offset);
132ssize_t pwrite(int fd, const void *buf, size_t count, off_t offset);
133
134#define CRC_START 0xFFFFFFFF
135
136static uint32_t strntoul(char *str, char **endptr, int base, size_t len) {
137  char *newstr;
138  uint32_t res = 0;
139
140  newstr = calloc(len + 1, sizeof(char));
141  if (newstr) {
142	strncpy(newstr, str, len);
143	res = strtoul(newstr, endptr, base);
144	free(newstr);
145  }
146  return res;
147}
148
149uint32_t compute_crc32(uint32_t crc, off_t start, size_t compute_len, int fd)
150{
151	uint8_t readbuf[1024];
152	ssize_t res;
153	off_t offset = start;
154
155	/* Read a buffer's worth of bytes  */
156	while (fd && (compute_len >= sizeof(readbuf))) {
157		res = pread(fd, readbuf, sizeof(readbuf), offset);
158		crc = crc32(crc, readbuf, res);
159		compute_len = compute_len - res;
160		offset += res;
161	}
162
163	/* Less than buffer-size bytes remains, read compute_len bytes */
164	if (fd && (compute_len > 0)) {
165	  res = pread(fd, readbuf, compute_len, offset);
166	  crc = crc32(crc, readbuf, res);
167	}
168
169	return crc;
170}
171
172int
173trx_fixup(int fd, const char *name)
174{
175	struct mtd_info_user mtdInfo;
176	unsigned long len;
177	void *ptr, *scan;
178	int bfd;
179	struct bcm_tag *tag;
180	ssize_t res;
181	uint32_t cfelen, imagelen, imagestart, rootfslen;
182	uint32_t imagecrc, rootfscrc, headercrc;
183	uint32_t offset = 0;
184	cfelen = imagelen = imagestart = imagecrc = rootfscrc = headercrc = rootfslen = 0;
185
186
187	if (ioctl(fd, MEMGETINFO, &mtdInfo) < 0) {
188		fprintf(stderr, "Failed to get mtd info\n");
189		goto err;
190	}
191
192	len = mtdInfo.size;
193	if (mtdInfo.size <= 0) {
194		fprintf(stderr, "Invalid MTD device size\n");
195		goto err;
196	}
197
198	bfd = mtd_open(name, true);
199	ptr = mmap(NULL, len, PROT_READ|PROT_WRITE, MAP_SHARED, bfd, 0);
200	if (!ptr || (ptr == (void *) -1)) {
201		perror("mmap");
202		goto err1;
203	}
204
205	tag = (struct bcm_tag *) (ptr);
206
207	cfelen = strntoul(&tag->cfe_length[0], NULL, 10, IMAGE_LEN);
208	if (cfelen) {
209	  fprintf(stderr, "Non-zero CFE length.  This is currently unsupported.\n");
210	  exit(1);
211	}
212
213	headercrc = compute_crc32(CRC_START, offset, offsetof(struct bcm_tag, header_crc), fd);
214	if (headercrc != *(uint32_t *)(&tag->header_crc)) {
215		fprintf(stderr, "Tag verify failed.  This may not be a valid image.\n");
216		exit(1);
217	}
218
219	sprintf(&tag->root_length[0], "%u", 0);
220	strncpy(&tag->total_length[0], &tag->kernel_length[0], IMAGE_LEN);
221
222	imagestart = sizeof(tag);
223	memcpy(&tag->image_crc, &tag->kernel_crc, sizeof(uint32_t));
224	memcpy(&tag->fskernel_crc, &tag->kernel_crc, sizeof(uint32_t));
225	rootfscrc = CRC_START;
226	memcpy(&tag->rootfs_crc, &rootfscrc, sizeof(uint32_t));
227	headercrc = crc32(CRC_START, tag, offsetof(struct bcm_tag, header_crc));
228	memcpy(&tag->header_crc, &headercrc, sizeof(uint32_t));
229
230	msync(ptr, sizeof(struct bcm_tag), MS_SYNC|MS_INVALIDATE);
231	munmap(ptr, len);
232	close(bfd);
233	return 0;
234
235err1:
236	close(bfd);
237err:
238	fprintf(stderr, "Error fixing up imagetag header\n");
239	return -1;
240}
241
242
243int
244trx_check(int imagefd, const char *mtd, char *buf, int *len)
245{
246    struct bcm_tag *tag = (const struct bcm_tag *) buf;
247	int fd;
248	uint32_t headerCRC;
249	uint32_t imageLen;
250
251	if (strcmp(mtd, "linux") != 0)
252		return 1;
253
254	*len = read(imagefd, buf, sizeof(struct bcm_tag));
255	if (*len < sizeof(struct bcm_tag)) {
256		fprintf(stdout, "Could not get image header, file too small (%d bytes)\n", *len);
257		return 0;
258	}
259	headerCRC = crc32buf(buf, offsetof(struct bcm_tag, header_crc));
260	if (*(uint32_t *)(&tag->header_crc) != headerCRC) {
261
262	  if (quiet < 2) {
263		fprintf(stderr, "Bad header CRC got %08x, calculated %08x\n",
264				*(uint32_t *)(&tag->header_crc), headerCRC);
265		fprintf(stderr, "This is not the correct file format; refusing to flash.\n"
266				"Please specify the correct file or use -f to force.\n");
267	  }
268	  return 0;
269	}
270
271	/* check if image fits to mtd device */
272	fd = mtd_check_open(mtd);
273	if(fd < 0) {
274		fprintf(stderr, "Could not open mtd device: %s\n", mtd);
275		exit(1);
276	}
277
278	imageLen = strntoul(&tag->total_length[0], NULL, 10, IMAGE_LEN);
279
280	if(mtdsize < imageLen) {
281		fprintf(stderr, "Image too big for partition: %s\n", mtd);
282		close(fd);
283		return 0;
284	}
285
286	close(fd);
287	return 1;
288}
289
290int
291mtd_fixtrx(const char *mtd, size_t offset, size_t data_size)
292{
293	int fd;
294	struct bcm_tag *tag;
295	char *buf;
296	ssize_t res;
297	size_t block_offset;
298	uint32_t cfelen, imagelen, imagestart, rootfslen;
299	uint32_t imagecrc, rootfscrc, headercrc;
300	cfelen = imagelen = imagestart = imagecrc = rootfscrc = headercrc = rootfslen = 0;
301
302	if (data_size)
303		fprintf(stderr, "Specifying data size in unsupported for imagetag\n");
304
305	if (quiet < 2)
306		fprintf(stderr, "Trying to fix trx header in %s at 0x%x...\n", mtd, offset);
307
308	block_offset = offset & ~(erasesize - 1);
309	offset -= block_offset;
310
311	fd = mtd_check_open(mtd);
312	if(fd < 0) {
313		fprintf(stderr, "Could not open mtd device: %s\n", mtd);
314		exit(1);
315	}
316
317	if (block_offset + erasesize > mtdsize) {
318		fprintf(stderr, "Offset too large, device size 0x%x\n", mtdsize);
319		exit(1);
320	}
321
322	buf = malloc(erasesize);
323	if (!buf) {
324		perror("malloc");
325		exit(1);
326	}
327
328	res = pread(fd, buf, erasesize, block_offset);
329	if (res != erasesize) {
330		perror("pread");
331		exit(1);
332	}
333
334	tag = (struct bcm_tag *) (buf + offset);
335
336	cfelen = strntoul(tag->cfe_length, NULL, 10, IMAGE_LEN);
337	if (cfelen) {
338	  fprintf(stderr, "Non-zero CFE length.  This is currently unsupported.\n");
339	  exit(1);
340	}
341
342	if (quiet < 2) {
343	  fprintf(stderr, "Verifying we actually have an imagetag.\n");
344	}
345
346	headercrc = compute_crc32(CRC_START, offset, offsetof(struct bcm_tag, header_crc), fd);
347	if (headercrc != *(uint32_t *)(&tag->header_crc)) {
348		fprintf(stderr, "Tag verify failed.  This may not be a valid image.\n");
349		exit(1);
350	}
351
352	if (quiet < 2) {
353	  fprintf(stderr, "Checking current fixed status.\n");
354	}
355
356	rootfslen = strntoul(&tag->root_length[0], NULL, 10, IMAGE_LEN);
357	if (rootfslen == 0) {
358	  if (quiet < 2)
359		fprintf(stderr, "Header already fixed, exiting\n");
360	  close(fd);
361	  return 0;
362	}
363
364	if (quiet < 2) {
365	  fprintf(stderr, "Setting root length to 0.\n");
366	}
367
368	sprintf(&tag->root_length[0], "%u", 0);
369	strncpy(&tag->total_length[0], &tag->kernel_length[0], IMAGE_LEN);
370
371	if (quiet < 2) {
372	  fprintf(stderr, "Recalculating CRCs.\n");
373	}
374
375	imagestart = sizeof(tag);
376	memcpy(&tag->image_crc, &tag->kernel_crc, sizeof(uint32_t));
377	memcpy(&tag->fskernel_crc, &tag->kernel_crc, sizeof(uint32_t));
378	rootfscrc = CRC_START;
379	memcpy(&tag->rootfs_crc, &rootfscrc, sizeof(uint32_t));
380	headercrc = crc32(CRC_START, tag, offsetof(struct bcm_tag, header_crc));
381	memcpy(&tag->header_crc, &headercrc, sizeof(uint32_t));
382
383	if (quiet < 2) {
384	  fprintf(stderr, "Erasing imagetag block\n");
385	}
386
387	if (mtd_erase_block(fd, block_offset)) {
388		fprintf(stderr, "Can't erase block at 0x%x (%s)\n", block_offset, strerror(errno));
389		exit(1);
390	}
391
392	if (quiet < 2) {
393	  fprintf(stderr, "New image crc32: 0x%x, rewriting block\n",
394			  *(uint32_t *)(&tag->image_crc));
395	  fprintf(stderr, "New header crc32: 0x%x, rewriting block\n", headercrc);
396	}
397
398	if (pwrite(fd, buf, erasesize, block_offset) != erasesize) {
399		fprintf(stderr, "Error writing block (%s)\n", strerror(errno));
400		exit(1);
401	}
402
403	if (quiet < 2)
404		fprintf(stderr, "Done.\n");
405
406	close (fd);
407	sync();
408	return 0;
409
410}
411