2 * jffs2 on-disk structure generator for mtd
4 * Copyright (C) 2008 Felix Fietkau <nbd@openwrt.org>
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License v2
8 * as published by the Free Software Foundation.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * JFFS2 -- Journalling Flash File System, Version 2.
16 * Copyright © 2001-2007 Red Hat, Inc.
17 * Created by David Woodhouse <dwmw2@infradead.org>
19 #include <sys/types.h>
33 #define PAD(x) (((x)+3)&~3)
35 #if BYTE_ORDER == BIG_ENDIAN
36 # define CLEANMARKER "\x19\x85\x20\x03\x00\x00\x00\x0c\xf0\x60\xdc\x98"
38 # define CLEANMARKER "\x85\x19\x03\x20\x0c\x00\x00\x00\xb1\xb0\x1e\xe4"
41 static int last_ino = 0;
42 static int last_version = 0;
43 static char *buf = NULL;
45 static int outfd = -1;
46 static int mtdofs = 0;
47 static int target_ino = 0;
49 static void prep_eraseblock(void);
51 static void pad(int size)
53 if ((ofs % size == 0) && (ofs < erasesize))
56 if (ofs < erasesize) {
57 memset(buf + ofs, 0xff, (size - (ofs % size)));
58 ofs += (size - (ofs % size));
60 ofs = ofs % erasesize;
62 mtd_erase_block(outfd, mtdofs);
63 write(outfd, buf, erasesize);
68 static inline int rbytes(void)
70 return erasesize - (ofs % erasesize);
73 static inline void add_data(char *ptr, int len)
75 if (ofs + len > erasesize) {
79 memcpy(buf + ofs, ptr, len);
83 static void prep_eraseblock(void)
88 add_data(CLEANMARKER, sizeof(CLEANMARKER) - 1);
91 static int add_dirent(const char *name, const char type, int parent)
93 struct jffs2_raw_dirent *de;
95 if (ofs - erasesize < sizeof(struct jffs2_raw_dirent) + strlen(name))
100 memset(buf + ofs, 0, sizeof(struct jffs2_raw_dirent));
101 de = (struct jffs2_raw_dirent *) (buf + ofs);
103 de->magic = JFFS2_MAGIC_BITMASK;
104 de->nodetype = JFFS2_NODETYPE_DIRENT;
106 de->name_crc = crc32(0, name, strlen(name));
107 de->ino = last_ino++;
109 de->totlen = sizeof(*de) + strlen(name);
110 de->hdr_crc = crc32(0, (void *) de, sizeof(struct jffs2_unknown_node) - 4);
111 de->version = last_version++;
113 de->nsize = strlen(name);
114 de->node_crc = crc32(0, (void *) de, sizeof(*de) - 8);
115 memcpy(de->name, name, strlen(name));
117 ofs += sizeof(struct jffs2_raw_dirent) + de->nsize;
123 static int add_dir(const char *name, int parent)
125 struct jffs2_raw_inode ri;
128 inode = add_dirent(name, IFTODT(S_IFDIR), parent);
130 if (rbytes() < sizeof(ri))
134 memset(&ri, 0, sizeof(ri));
135 ri.magic = JFFS2_MAGIC_BITMASK;
136 ri.nodetype = JFFS2_NODETYPE_INODE;
137 ri.totlen = sizeof(ri);
138 ri.hdr_crc = crc32(0, &ri, sizeof(struct jffs2_unknown_node) - 4);
141 ri.mode = S_IFDIR | 0755;
143 ri.atime = ri.ctime = ri.mtime = 0;
144 ri.isize = ri.csize = ri.dsize = 0;
146 ri.node_crc = crc32(0, &ri, sizeof(ri) - 8);
149 add_data((char *) &ri, sizeof(ri));
154 static void add_file(const char *name, int parent)
156 int inode, f_offset = 0, fd;
157 struct jffs2_raw_inode ri;
162 if (stat(name, &st)) {
163 fprintf(stderr, "File %s does not exist\n", name);
167 fname = strrchr(name, '/');
173 inode = add_dirent(fname, IFTODT(S_IFREG), parent);
174 memset(&ri, 0, sizeof(ri));
175 ri.magic = JFFS2_MAGIC_BITMASK;
176 ri.nodetype = JFFS2_NODETYPE_INODE;
179 ri.mode = st.st_mode;
181 ri.atime = st.st_atime;
182 ri.ctime = st.st_ctime;
183 ri.mtime = st.st_mtime;
184 ri.isize = st.st_size;
190 fprintf(stderr, "File %s does not exist\n", name);
198 len = rbytes() - sizeof(ri);
206 if (len > sizeof(wbuf))
209 len = read(fd, wbuf, len);
213 ri.totlen = sizeof(ri) + len;
214 ri.hdr_crc = crc32(0, &ri, sizeof(struct jffs2_unknown_node) - 4);
215 ri.version = ++last_version;
216 ri.offset = f_offset;
217 ri.csize = ri.dsize = len;
218 ri.node_crc = crc32(0, &ri, sizeof(ri) - 8);
219 ri.data_crc = crc32(0, wbuf, len);
221 add_data((char *) &ri, sizeof(ri));
230 int mtd_replace_jffs2(const char *mtd, int fd, int ofs, const char *filename)
235 buf = malloc(erasesize);
239 add_file(filename, target_ino);
242 /* add eof marker, pad to eraseblock size and write the data */
243 add_data(JFFS2_EOF, sizeof(JFFS2_EOF) - 1);
248 trx_fixup(outfd, mtd);
250 return (mtdofs - ofs);
253 void mtd_parse_jffs2data(const char *buf, const char *dir)
255 struct jffs2_unknown_node *node = (struct jffs2_unknown_node *) buf;
256 unsigned int ofs = 0;
258 while (ofs < erasesize) {
259 node = (struct jffs2_unknown_node *) (buf + ofs);
260 if (node->magic != 0x1985)
263 ofs += PAD(node->totlen);
264 if (node->nodetype == JFFS2_NODETYPE_DIRENT) {
265 struct jffs2_raw_dirent *de = (struct jffs2_raw_dirent *) node;
267 /* is this the right directory name and is it a subdirectory of / */
268 if (*dir && (de->pino == 1) && !strncmp((char *) de->name, dir, de->nsize))
269 target_ino = de->ino;
271 /* store the last inode and version numbers for adding extra files */
272 if (last_ino < de->ino)
274 if (last_version < de->version)
275 last_version = de->version;
280 int mtd_write_jffs2(const char *mtd, const char *filename, const char *dir)
282 int err = -1, fdeof = 0;
284 outfd = mtd_check_open(mtd);
289 fprintf(stderr, "Appending %s to jffs2 partition %s\n", filename, mtd);
291 buf = malloc(erasesize);
293 fprintf(stderr, "Out of memory!\n");
300 /* parse the structure of the jffs2 first
301 * locate the directory that the file is going to be placed in */
303 struct jffs2_unknown_node *node = (struct jffs2_unknown_node *) buf;
305 if (read(outfd, buf, erasesize) != erasesize) {
311 if (node->magic == 0x8519) {
312 fprintf(stderr, "Error: wrong endianness filesystem\n");
316 /* assume no magic == end of filesystem
317 * the filesystem will probably end with be32(0xdeadc0de) */
318 if (node->magic != 0x1985)
321 mtd_parse_jffs2data(buf, dir);
325 fprintf(stderr, "Error: No room for additional data\n");
329 /* jump back one eraseblock */
331 lseek(outfd, mtdofs, SEEK_SET);
339 target_ino = add_dir(dir, 1);
341 add_file(filename, target_ino);
344 /* add eof marker, pad to eraseblock size and write the data */
345 add_data(JFFS2_EOF, sizeof(JFFS2_EOF) - 1);
351 trx_fixup(outfd, mtd);