[PATCH] bcm63xx-bootfs: add tool accessing JFFS2 bootfs images
Rafał Miłecki
zajec5 at gmail.com
Tue Mar 23 13:47:09 GMT 2021
From: Rafał Miłecki <rafal at milecki.pl>
On BCM4908 it's required to rename cferam.000 file in firmware image
before flashing it.
Signed-off-by: Rafał Miłecki <rafal at milecki.pl>
---
package/utils/bcm63xx-bootfs/Makefile | 34 ++
package/utils/bcm63xx-bootfs/src/Makefile | 7 +
.../utils/bcm63xx-bootfs/src/bcm63xx-bootfs.c | 378 ++++++++++++++++++
3 files changed, 419 insertions(+)
create mode 100644 package/utils/bcm63xx-bootfs/Makefile
create mode 100644 package/utils/bcm63xx-bootfs/src/Makefile
create mode 100644 package/utils/bcm63xx-bootfs/src/bcm63xx-bootfs.c
diff --git a/package/utils/bcm63xx-bootfs/Makefile b/package/utils/bcm63xx-bootfs/Makefile
new file mode 100644
index 0000000000..f62efeba33
--- /dev/null
+++ b/package/utils/bcm63xx-bootfs/Makefile
@@ -0,0 +1,34 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+include $(TOPDIR)/rules.mk
+
+PKG_NAME:=bcm63xx-bootfs
+PKG_RELEASE:=1
+
+include $(INCLUDE_DIR)/package.mk
+
+define Package/bcm63xx-bootfs
+ SECTION:=utils
+ CATEGORY:=Base system
+ TITLE:=Utility for modifying JFFS2 bootfs images
+ MAINTAINER:=Rafał Miłecki <rafal at milecki.pl>
+ DEPENDS:=@TARGET_bcm4908
+endef
+
+define Package/bcm63xx-bootfs/description
+ This package contains an utility that can modify bootfs images. It's useful
+ when image needs to be adjusted before flashing it.
+endef
+
+define Build/Compile
+ $(MAKE) -C $(PKG_BUILD_DIR) \
+ CC="$(TARGET_CC)" \
+ CFLAGS="$(TARGET_CFLAGS) -Wall"
+endef
+
+define Package/bcm63xx-bootfs/install
+ $(INSTALL_DIR) $(1)/usr/bin
+ $(INSTALL_BIN) $(PKG_BUILD_DIR)/bcm63xx-bootfs $(1)/usr/bin/
+endef
+
+$(eval $(call BuildPackage,bcm63xx-bootfs))
diff --git a/package/utils/bcm63xx-bootfs/src/Makefile b/package/utils/bcm63xx-bootfs/src/Makefile
new file mode 100644
index 0000000000..e06de9739f
--- /dev/null
+++ b/package/utils/bcm63xx-bootfs/src/Makefile
@@ -0,0 +1,7 @@
+all: bcm63xx-bootfs
+
+bcm63xx-bootfs:
+ $(CC) $(CFLAGS) -o $@ bcm63xx-bootfs.c -Wall
+
+clean:
+ rm -f bcm63xx-bootfs
diff --git a/package/utils/bcm63xx-bootfs/src/bcm63xx-bootfs.c b/package/utils/bcm63xx-bootfs/src/bcm63xx-bootfs.c
new file mode 100644
index 0000000000..07bb4d4e7d
--- /dev/null
+++ b/package/utils/bcm63xx-bootfs/src/bcm63xx-bootfs.c
@@ -0,0 +1,378 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2021 Rafał Miłecki <rafal at milecki.pl>
+ */
+
+#include <endian.h>
+#include <errno.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+static int debug;
+
+#define JFFS2_MAGIC_BITMASK 0x1985
+
+#define JFFS2_COMPR_NONE 0x00
+#define JFFS2_COMPR_ZERO 0x01
+#define JFFS2_COMPR_RTIME 0x02
+#define JFFS2_COMPR_RUBINMIPS 0x03
+#define JFFS2_COMPR_COPY 0x04
+#define JFFS2_COMPR_DYNRUBIN 0x05
+#define JFFS2_COMPR_ZLIB 0x06
+#define JFFS2_COMPR_LZO 0x07
+/* Compatibility flags. */
+#define JFFS2_COMPAT_MASK 0xc000 /* What do to if an unknown nodetype is found */
+#define JFFS2_NODE_ACCURATE 0x2000
+/* INCOMPAT: Fail to mount the filesystem */
+#define JFFS2_FEATURE_INCOMPAT 0xc000
+/* ROCOMPAT: Mount read-only */
+#define JFFS2_FEATURE_ROCOMPAT 0x8000
+/* RWCOMPAT_COPY: Mount read/write, and copy the node when it's GC'd */
+#define JFFS2_FEATURE_RWCOMPAT_COPY 0x4000
+/* RWCOMPAT_DELETE: Mount read/write, and delete the node when it's GC'd */
+#define JFFS2_FEATURE_RWCOMPAT_DELETE 0x0000
+
+#define JFFS2_NODETYPE_DIRENT (JFFS2_FEATURE_INCOMPAT | JFFS2_NODE_ACCURATE | 1)
+
+typedef struct {
+ uint32_t v32;
+} __attribute__((packed)) jint32_t;
+
+typedef struct {
+ uint16_t v16;
+} __attribute__((packed)) jint16_t;
+
+struct jffs2_unknown_node
+{
+ /* All start like this */
+ jint16_t magic;
+ jint16_t nodetype;
+ jint32_t totlen; /* So we can skip over nodes we don't grok */
+ jint32_t hdr_crc;
+};
+
+struct jffs2_raw_dirent
+{
+ jint16_t magic;
+ jint16_t nodetype; /* == JFFS2_NODETYPE_DIRENT */
+ jint32_t totlen;
+ jint32_t hdr_crc;
+ jint32_t pino;
+ jint32_t version;
+ jint32_t ino; /* == zero for unlink */
+ jint32_t mctime;
+ uint8_t nsize;
+ uint8_t type;
+ uint8_t unused[2];
+ jint32_t node_crc;
+ jint32_t name_crc;
+ uint8_t name[0];
+};
+
+#define je16_to_cpu(x) ((x).v16)
+#define je32_to_cpu(x) ((x).v32)
+
+/**************************************************
+ * CRC32
+ **************************************************/
+
+static const uint32_t crc32_tbl[] = {
+ 0x00000000, 0x77073096, 0xee0e612c, 0x990951ba,
+ 0x076dc419, 0x706af48f, 0xe963a535, 0x9e6495a3,
+ 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
+ 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91,
+ 0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de,
+ 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
+ 0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec,
+ 0x14015c4f, 0x63066cd9, 0xfa0f3d63, 0x8d080df5,
+ 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
+ 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b,
+ 0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940,
+ 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
+ 0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116,
+ 0x21b4f4b5, 0x56b3c423, 0xcfba9599, 0xb8bda50f,
+ 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
+ 0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d,
+ 0x76dc4190, 0x01db7106, 0x98d220bc, 0xefd5102a,
+ 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
+ 0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818,
+ 0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01,
+ 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
+ 0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457,
+ 0x65b0d9c6, 0x12b7e950, 0x8bbeb8ea, 0xfcb9887c,
+ 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
+ 0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2,
+ 0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb,
+ 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
+ 0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9,
+ 0x5005713c, 0x270241aa, 0xbe0b1010, 0xc90c2086,
+ 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
+ 0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4,
+ 0x59b33d17, 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad,
+ 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
+ 0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683,
+ 0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8,
+ 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
+ 0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe,
+ 0xf762575d, 0x806567cb, 0x196c3671, 0x6e6b06e7,
+ 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
+ 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5,
+ 0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252,
+ 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
+ 0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60,
+ 0xdf60efc3, 0xa867df55, 0x316e8eef, 0x4669be79,
+ 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
+ 0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f,
+ 0xc5ba3bbe, 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04,
+ 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
+ 0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a,
+ 0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713,
+ 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
+ 0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21,
+ 0x86d3d2d4, 0xf1d4e242, 0x68ddb3f8, 0x1fda836e,
+ 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
+ 0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c,
+ 0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45,
+ 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
+ 0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db,
+ 0xaed16a4a, 0xd9d65adc, 0x40df0b66, 0x37d83bf0,
+ 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
+ 0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6,
+ 0xbad03605, 0xcdd70693, 0x54de5729, 0x23d967bf,
+ 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
+ 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d,
+};
+
+uint32_t bcm63xx_bootfs_crc32(uint32_t crc, const void *buf, size_t len) {
+ const uint8_t *in = buf;
+
+ while (len) {
+ crc = crc32_tbl[(crc ^ *in) & 0xff] ^ (crc >> 8);
+ in++;
+ len--;
+ }
+
+ return crc;
+}
+
+/**************************************************
+ * Commands
+ **************************************************/
+
+static int bcm63xx_bootfs_ls(int argc, char **argv) {
+ struct jffs2_unknown_node node;
+ struct jffs2_raw_dirent dirent;
+ const char *pathname;
+ size_t offset;
+ size_t bytes;
+ FILE *fp;
+ int err = 0;
+
+ if (argc < 1 + 1 + 1) {
+ fprintf(stderr, "No enough arguments passed\n");
+ err = -EINVAL;
+ goto out;
+ }
+ pathname = argv[2];
+
+ fp = fopen(pathname, "r+");
+ if (!fp) {
+ fprintf(stderr, "Failed to open %s\n", pathname);
+ err = -EIO;
+ goto out;
+ }
+
+ for (offset = 0; ; offset += (je32_to_cpu(node.totlen) + 0x03) & ~0x03) {
+ char name[FILENAME_MAX];
+
+ fseek(fp, offset, SEEK_SET);
+
+ bytes = fread(&node, 1, sizeof(node), fp);
+ if (bytes != sizeof(node)) {
+ fprintf(stderr, "Failed to read %zu bytes\n", sizeof(node));
+ err = -EIO;
+ goto err_close;
+ }
+
+ if (je16_to_cpu(node.magic) != JFFS2_MAGIC_BITMASK) {
+ break;
+ }
+
+ if (je16_to_cpu(node.nodetype) != JFFS2_NODETYPE_DIRENT) {
+ continue;
+ }
+
+ bytes += fread((uint8_t *)&dirent + sizeof(node), 1, sizeof(dirent) - sizeof(node), fp);
+ if (bytes != sizeof(dirent)) {
+ fprintf(stderr, "Failed to read %zu bytes\n", sizeof(node));
+ err = -EIO;
+ goto err_close;
+ }
+
+ if (dirent.nsize + 1 > sizeof(name)) {
+ fprintf(stderr, "Too long filename\n");
+ err = -ENOMEM;
+ continue;
+ }
+
+ bytes = fread(name, 1, dirent.nsize, fp);
+ if (bytes != dirent.nsize) {
+ fprintf(stderr, "Failed to read filename\n");
+ err = -EIO;
+ goto err_close;
+ }
+ name[bytes] = '\0';
+
+ printf("%s\n", name);
+ }
+
+err_close:
+ fclose(fp);
+out:
+ return err;
+}
+
+static int bcm63xx_bootfs_mv(int argc, char **argv) {
+ struct jffs2_unknown_node node;
+ struct jffs2_raw_dirent dirent;
+ const char *pathname;
+ const char *oldname;
+ const char *newname;
+ size_t offset;
+ size_t bytes;
+ FILE *fp;
+ int err = -ENOENT;
+
+ if (argc < 1 + 1 + 3) {
+ fprintf(stderr, "No enough arguments passed\n");
+ err = -EINVAL;
+ goto out;
+ }
+ pathname = argv[2];
+ oldname = argv[3];
+ newname = argv[4];
+
+ if (strlen(newname) != strlen(oldname)) {
+ fprintf(stderr, "New filename must have the same length as the old one\n");
+ err = -EINVAL;
+ goto out;
+ }
+
+ fp = fopen(pathname, "r+");
+ if (!fp) {
+ fprintf(stderr, "Failed to open %s\n", pathname);
+ err = -EIO;
+ goto out;
+ }
+
+ for (offset = 0; ; offset += (je32_to_cpu(node.totlen) + 0x03) & ~0x03) {
+ char name[FILENAME_MAX];
+ uint32_t crc32;
+
+ fseek(fp, offset, SEEK_SET);
+
+ bytes = fread(&node, 1, sizeof(node), fp);
+ if (bytes != sizeof(node)) {
+ fprintf(stderr, "Failed to read %zu bytes\n", sizeof(node));
+ err = -EIO;
+ goto err_close;
+ }
+
+ if (je16_to_cpu(node.magic) != JFFS2_MAGIC_BITMASK) {
+ break;
+ }
+
+ if (je16_to_cpu(node.nodetype) != JFFS2_NODETYPE_DIRENT) {
+ continue;
+ }
+
+ bytes += fread((uint8_t *)&dirent + sizeof(node), 1, sizeof(dirent) - sizeof(node), fp);
+ if (bytes != sizeof(dirent)) {
+ fprintf(stderr, "Failed to read %zu bytes\n", sizeof(node));
+ err = -EIO;
+ goto err_close;
+ }
+
+ if (dirent.nsize + 1 > sizeof(name)) {
+ fprintf(stderr, "Too long filename\n");
+ err = -ENOMEM;
+ continue;
+ }
+
+ bytes = fread(name, 1, dirent.nsize, fp);
+ if (bytes != dirent.nsize) {
+ fprintf(stderr, "Failed to read filename\n");
+ err = -EIO;
+ goto err_close;
+ }
+ name[bytes] = '\0';
+
+ if (debug)
+ printf("offset:%08zx name_crc:%04x filename:%-15s \n", offset, je32_to_cpu(dirent.name_crc), name);
+
+ if (strcmp(name, oldname)) {
+ continue;
+ }
+
+ fseek(fp, offset + offsetof(struct jffs2_raw_dirent, name_crc), SEEK_SET);
+ crc32 = bcm63xx_bootfs_crc32(0, newname, dirent.nsize);
+ bytes = fwrite(&crc32, 1, sizeof(crc32), fp);
+ if (bytes != sizeof(crc32)) {
+ fprintf(stderr, "Failed to write new CRC32\n");
+ err = -EIO;
+ goto err_close;
+ }
+
+ fseek(fp, offset + offsetof(struct jffs2_raw_dirent, name), SEEK_SET);
+ bytes = fwrite(newname, 1, dirent.nsize, fp);
+ if (bytes != dirent.nsize) {
+ fprintf(stderr, "Failed to write new filename\n");
+ err = -EIO;
+ goto err_close;
+ }
+
+ printf("Successfully renamed %s to the %s\n", oldname, newname);
+
+ err = 0;
+
+ break;
+ }
+
+ if (err)
+ fprintf(stderr, "Failed to find %s\n", oldname);
+
+err_close:
+ fclose(fp);
+out:
+ return err;
+}
+
+/**************************************************
+ * Start
+ **************************************************/
+
+static void bcm63xx_bootfs_usage() {
+ printf("Usage:\n");
+ printf("\n");
+ printf("Listing files:\n");
+ printf("\tbcm4908img ls <bootfs>\t\t\t\tlist files in the bootfs image\n");
+ printf("\n");
+ printf("Renaming a file:\n");
+ printf("\tbcm4908img mv <bootfs> <oldname> <newname>\trename file in the bootfs image\n");
+}
+
+int main(int argc, char **argv) {
+ if (argc > 1) {
+ if (!strcmp(argv[1], "ls"))
+ return bcm63xx_bootfs_ls(argc, argv);
+ else if (!strcmp(argv[1], "mv"))
+ return bcm63xx_bootfs_mv(argc, argv);
+ }
+
+ bcm63xx_bootfs_usage();
+ return 0;
+}
--
2.26.2
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