mtd: improve check for TRX header being already fixed
[openwrt/openwrt.git] / package / system / mtd / src / trx.c
1 /*
2 * trx.c
3 *
4 * Copyright (C) 2005 Mike Baker
5 * Copyright (C) 2008 Felix Fietkau <nbd@nbd.name>
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version 2
10 * of the License, or (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
20 */
21
22 #include <stdio.h>
23 #include <stdlib.h>
24 #include <stddef.h>
25 #include <unistd.h>
26 #include <fcntl.h>
27 #include <sys/mman.h>
28 #include <sys/stat.h>
29 #include <endian.h>
30 #include <string.h>
31 #include <errno.h>
32
33 #include <sys/ioctl.h>
34 #include <mtd/mtd-user.h>
35 #include "mtd.h"
36 #include "crc32.h"
37
38 #define TRX_MAGIC 0x30524448 /* "HDR0" */
39 #define TRX_CRC32_DATA_OFFSET 12 /* First 12 bytes are not covered by CRC32 */
40 #define TRX_CRC32_DATA_SIZE 16
41 struct trx_header {
42 uint32_t magic; /* "HDR0" */
43 uint32_t len; /* Length of file including header */
44 uint32_t crc32; /* 32-bit CRC from flag_version to end of file */
45 uint32_t flag_version; /* 0:15 flags, 16:31 version */
46 uint32_t offsets[3]; /* Offsets of partitions from start of header */
47 };
48
49 #define min(x,y) ({ \
50 typeof(x) _x = (x); \
51 typeof(y) _y = (y); \
52 (void) (&_x == &_y); \
53 _x < _y ? _x : _y; })
54
55 #if __BYTE_ORDER == __BIG_ENDIAN
56 #define STORE32_LE(X) ((((X) & 0x000000FF) << 24) | (((X) & 0x0000FF00) << 8) | (((X) & 0x00FF0000) >> 8) | (((X) & 0xFF000000) >> 24))
57 #elif __BYTE_ORDER == __LITTLE_ENDIAN
58 #define STORE32_LE(X) (X)
59 #else
60 #error unknown endianness!
61 #endif
62
63 ssize_t pread(int fd, void *buf, size_t count, off_t offset);
64 ssize_t pwrite(int fd, const void *buf, size_t count, off_t offset);
65
66 int
67 trx_fixup(int fd, const char *name)
68 {
69 struct mtd_info_user mtdInfo;
70 unsigned long len;
71 struct trx_header *trx;
72 void *ptr, *scan;
73 int bfd;
74
75 if (ioctl(fd, MEMGETINFO, &mtdInfo) < 0) {
76 fprintf(stderr, "Failed to get mtd info\n");
77 goto err;
78 }
79
80 len = mtdInfo.size;
81 if (mtdInfo.size <= 0) {
82 fprintf(stderr, "Invalid MTD device size\n");
83 goto err;
84 }
85
86 bfd = mtd_open(name, true);
87 ptr = mmap(NULL, len, PROT_READ|PROT_WRITE, MAP_SHARED, bfd, 0);
88 if (!ptr || (ptr == (void *) -1)) {
89 perror("mmap");
90 fprintf(stderr, "Mapping the TRX header failed\n");
91 goto err1;
92 }
93
94 trx = ptr;
95 if (trx->magic != TRX_MAGIC) {
96 fprintf(stderr, "TRX header not found\n");
97 goto err;
98 }
99
100 scan = ptr + offsetof(struct trx_header, flag_version);
101 trx->crc32 = crc32buf(scan, trx->len - (scan - ptr));
102 msync(ptr, sizeof(struct trx_header), MS_SYNC|MS_INVALIDATE);
103 munmap(ptr, len);
104 close(bfd);
105 return 0;
106
107 err1:
108 close(bfd);
109 err:
110 return -1;
111 }
112
113 #ifndef target_ar71xx
114 int
115 trx_check(int imagefd, const char *mtd, char *buf, int *len)
116 {
117 const struct trx_header *trx = (const struct trx_header *) buf;
118 int fd;
119
120 if (strcmp(mtd, "firmware") != 0)
121 return 1;
122
123 if (*len < 32) {
124 *len += read(imagefd, buf + *len, 32 - *len);
125 if (*len < 32) {
126 fprintf(stdout, "Could not get image header, file too small (%d bytes)\n", *len);
127 return 0;
128 }
129 }
130
131 if (trx->magic != TRX_MAGIC || trx->len < sizeof(struct trx_header)) {
132 if (quiet < 2) {
133 fprintf(stderr, "Bad trx header\n");
134 fprintf(stderr, "This is not the correct file format; refusing to flash.\n"
135 "Please specify the correct file or use -f to force.\n");
136 }
137 return 0;
138 }
139
140 /* check if image fits to mtd device */
141 fd = mtd_check_open(mtd);
142 if(fd < 0) {
143 fprintf(stderr, "Could not open mtd device: %s\n", mtd);
144 exit(1);
145 }
146
147 if(mtdsize < trx->len) {
148 fprintf(stderr, "Image too big for partition: %s\n", mtd);
149 close(fd);
150 return 0;
151 }
152
153 close(fd);
154 return 1;
155 }
156 #endif
157
158 int
159 mtd_fixtrx(const char *mtd, size_t offset, size_t data_size)
160 {
161 size_t data_offset;
162 int fd;
163 struct trx_header *trx;
164 char *first_block;
165 char *buf, *to;
166 ssize_t res;
167 size_t block_offset;
168
169 if (quiet < 2)
170 fprintf(stderr, "Trying to fix trx header in %s at 0x%x...\n", mtd, offset);
171
172 fd = mtd_check_open(mtd);
173 if(fd < 0) {
174 fprintf(stderr, "Could not open mtd device: %s\n", mtd);
175 exit(1);
176 }
177
178 data_offset = offset + TRX_CRC32_DATA_OFFSET;
179 if (data_size)
180 data_size += TRX_CRC32_DATA_SIZE;
181 else
182 data_size = erasesize - TRX_CRC32_DATA_OFFSET;
183
184 block_offset = offset & ~(erasesize - 1);
185 offset -= block_offset;
186
187 if (data_offset + data_size > mtdsize) {
188 fprintf(stderr, "Offset too large, device size 0x%x\n", mtdsize);
189 exit(1);
190 }
191
192 first_block = malloc(erasesize);
193 if (!first_block) {
194 perror("malloc");
195 exit(1);
196 }
197
198 res = pread(fd, first_block, erasesize, block_offset);
199 if (res != erasesize) {
200 perror("pread");
201 exit(1);
202 }
203
204 trx = (struct trx_header *)(first_block + offset);
205 if (trx->magic != STORE32_LE(0x30524448)) {
206 fprintf(stderr, "No trx magic found\n");
207 exit(1);
208 }
209
210 buf = malloc(data_size);
211 if (!buf) {
212 perror("malloc");
213 exit(1);
214 }
215
216 to = buf;
217 while (data_size) {
218 size_t read_block_offset = data_offset & ~(erasesize - 1);
219 size_t read_chunk;
220
221 read_chunk = erasesize - (data_offset & (erasesize - 1));
222 read_chunk = min(read_chunk, data_size);
223
224 /* Read from good blocks only to match CFE behavior */
225 if (!mtd_block_is_bad(fd, read_block_offset)) {
226 res = pread(fd, to, read_chunk, data_offset);
227 if (res != read_chunk) {
228 perror("pread");
229 exit(1);
230 }
231 to += read_chunk;
232 }
233
234 data_offset += read_chunk;
235 data_size -= read_chunk;
236 }
237 data_size = to - buf;
238
239 if (trx->len == STORE32_LE(data_size + TRX_CRC32_DATA_OFFSET) &&
240 trx->crc32 == STORE32_LE(crc32buf(buf, data_size))) {
241 if (quiet < 2)
242 fprintf(stderr, "Header already fixed, exiting\n");
243 close(fd);
244 return 0;
245 }
246
247 trx->len = STORE32_LE(data_size + offsetof(struct trx_header, flag_version));
248
249 trx->crc32 = STORE32_LE(crc32buf(buf, data_size));
250 if (mtd_erase_block(fd, block_offset)) {
251 fprintf(stderr, "Can't erease block at 0x%x (%s)\n", block_offset, strerror(errno));
252 exit(1);
253 }
254
255 if (quiet < 2)
256 fprintf(stderr, "New crc32: 0x%x, rewriting block\n", trx->crc32);
257
258 if (pwrite(fd, first_block, erasesize, block_offset) != erasesize) {
259 fprintf(stderr, "Error writing block (%s)\n", strerror(errno));
260 exit(1);
261 }
262
263 if (quiet < 2)
264 fprintf(stderr, "Done.\n");
265
266 close (fd);
267 sync();
268 return 0;
269
270 }