kernel: mtdsplit: Add support for D-link JBOOT
authorPawel Dembicki <paweldembicki@gmail.com>
Sun, 4 Feb 2018 12:11:16 +0000 (13:11 +0100)
committerJohn Crispin <john@phrozen.org>
Sun, 11 Feb 2018 15:02:52 +0000 (16:02 +0100)
The D-Link devices with JBOOT bootloader use their own kernel
image header (stag + sch2 headers).

This driver find jImage header and set rootfs start after kernel file.

Signed-off-by: Pawel Dembicki <paweldembicki@gmail.com>
target/linux/generic/config-3.18
target/linux/generic/config-4.14
target/linux/generic/config-4.4
target/linux/generic/config-4.9
target/linux/generic/files/drivers/mtd/mtdsplit/Kconfig
target/linux/generic/files/drivers/mtd/mtdsplit/Makefile
target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit_jimage.c [new file with mode: 0644]

index 7df43be..0424553 100644 (file)
@@ -2272,6 +2272,7 @@ CONFIG_MTD_SPLIT=y
 # CONFIG_MTD_SPLIT_FIRMWARE is not set
 CONFIG_MTD_SPLIT_FIRMWARE_NAME="firmware"
 # CONFIG_MTD_SPLIT_FIT_FW is not set
+# CONFIG_MTD_SPLIT_JIMAGE_FW is not set
 # CONFIG_MTD_SPLIT_LZMA_FW is not set
 # CONFIG_MTD_SPLIT_MINOR_FW is not set
 # CONFIG_MTD_SPLIT_SEAMA_FW is not set
index 81b82a0..1048e3d 100644 (file)
@@ -2801,6 +2801,7 @@ CONFIG_MTD_SPLIT=y
 # CONFIG_MTD_SPLIT_FIRMWARE is not set
 CONFIG_MTD_SPLIT_FIRMWARE_NAME="firmware"
 # CONFIG_MTD_SPLIT_FIT_FW is not set
+# CONFIG_MTD_SPLIT_JIMAGE_FW is not set
 # CONFIG_MTD_SPLIT_LZMA_FW is not set
 # CONFIG_MTD_SPLIT_MINOR_FW is not set
 # CONFIG_MTD_SPLIT_SEAMA_FW is not set
index 0507569..3285000 100644 (file)
@@ -2378,6 +2378,7 @@ CONFIG_MTD_SPLIT=y
 # CONFIG_MTD_SPLIT_FIRMWARE is not set
 CONFIG_MTD_SPLIT_FIRMWARE_NAME="firmware"
 # CONFIG_MTD_SPLIT_FIT_FW is not set
+# CONFIG_MTD_SPLIT_JIMAGE_FW is not set
 # CONFIG_MTD_SPLIT_LZMA_FW is not set
 # CONFIG_MTD_SPLIT_MINOR_FW is not set
 # CONFIG_MTD_SPLIT_SEAMA_FW is not set
index 88742eb..344749e 100644 (file)
@@ -2649,6 +2649,7 @@ CONFIG_MTD_SPLIT=y
 # CONFIG_MTD_SPLIT_FIRMWARE is not set
 CONFIG_MTD_SPLIT_FIRMWARE_NAME="firmware"
 # CONFIG_MTD_SPLIT_FIT_FW is not set
+# CONFIG_MTD_SPLIT_JIMAGE_FW is not set
 # CONFIG_MTD_SPLIT_LZMA_FW is not set
 # CONFIG_MTD_SPLIT_MINOR_FW is not set
 # CONFIG_MTD_SPLIT_SEAMA_FW is not set
index 4a15d48..81ece43 100644 (file)
@@ -69,3 +69,8 @@ config MTD_SPLIT_MINOR_FW
        bool "Mikrotik NOR image based firmware partition parser"
        depends on MTD_SPLIT_SUPPORT
        select MTD_SPLIT
+
+config MTD_SPLIT_JIMAGE_FW
+       bool "JBOOT Image based firmware partition parser"
+       depends on MTD_SPLIT_SUPPORT
+       select MTD_SPLIT
index fab85ca..206e754 100644 (file)
@@ -10,3 +10,4 @@ obj-$(CONFIG_MTD_SPLIT_BRNIMAGE_FW) += mtdsplit_brnimage.o
 obj-$(CONFIG_MTD_SPLIT_EVA_FW) += mtdsplit_eva.o
 obj-$(CONFIG_MTD_SPLIT_WRGG_FW) += mtdsplit_wrgg.o
 obj-$(CONFIG_MTD_SPLIT_MINOR_FW) += mtdsplit_minor.o
+obj-$(CONFIG_MTD_SPLIT_JIMAGE_FW) += mtdsplit_jimage.o
diff --git a/target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit_jimage.c b/target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit_jimage.c
new file mode 100644 (file)
index 0000000..51544a7
--- /dev/null
@@ -0,0 +1,277 @@
+/*
+ *  Copyright (C) 2018 PaweĊ‚ Dembicki <paweldembicki@gmail.com> 
+ *
+ *  Based on: mtdsplit_uimage.c
+ *  Copyright (C) 2013 Gabor Juhos <juhosg@openwrt.org>
+ *
+ *  This program is free software; you can redistribute it and/or modify it
+ *  under the terms of the GNU General Public License version 2 as published
+ *  by the Free Software Foundation.
+ *
+ */
+
+#define pr_fmt(fmt)    KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
+#include <linux/byteorder/generic.h>
+
+#include "mtdsplit.h"
+
+#define MAX_HEADER_LEN ( STAG_SIZE + SCH2_SIZE )
+
+#define STAG_SIZE 16
+#define STAG_ID 0x04
+#define STAG_MAGIC 0x2B24
+
+#define SCH2_SIZE 40
+#define SCH2_MAGIC 0x2124
+#define SCH2_VER 0x02
+
+/*
+ * Jboot image header,
+ * all data in little endian.
+ */
+
+struct jimage_header           //stag + sch2 jboot joined headers
+{
+       uint8_t stag_cmark;             // in factory 0xFF , in sysupgrade must be the same as stag_id
+       uint8_t stag_id;                // 0x04
+       uint16_t stag_magic;            //magic 0x2B24
+       uint32_t stag_time_stamp;       // timestamp calculated in jboot way
+       uint32_t stag_image_length;     // lentgh of kernel + sch2 header
+       uint16_t stag_image_checksum;   // negated jboot_checksum of sch2 + kernel
+       uint16_t stag_tag_checksum;     // negated jboot_checksum of stag header data
+       uint16_t sch2_magic;            // magic 0x2124
+       uint8_t sch2_cp_type;   // 0x00 for flat, 0x01 for jz, 0x02 for gzip, 0x03 for lzma
+       uint8_t sch2_version;   // 0x02 for sch2
+       uint32_t sch2_ram_addr; // ram entry address
+       uint32_t sch2_image_len;        // kernel image length
+       uint32_t sch2_image_crc32;      // kernel image crc
+       uint32_t sch2_start_addr;       // ram start address
+       uint32_t sch2_rootfs_addr;      // rootfs flash address
+       uint32_t sch2_rootfs_len;       // rootfls length
+       uint32_t sch2_rootfs_crc32;     // rootfs crc32
+       uint32_t sch2_header_crc32;     // sch2 header crc32, durring calculation this area is replaced by zero
+       uint16_t sch2_header_length;    // sch2 header length: 0x28
+       uint16_t sch2_cmd_line_length;  // cmd line length, known zeros
+};
+
+static int
+read_jimage_header(struct mtd_info *mtd, size_t offset, u_char *buf,
+                  size_t header_len)
+{
+       size_t retlen;
+       int ret;
+
+       ret = mtd_read(mtd, offset, header_len, &retlen, buf);
+       if (ret) {
+               pr_debug("read error in \"%s\"\n", mtd->name);
+               return ret;
+       }
+
+       if (retlen != header_len) {
+               pr_debug("short read in \"%s\"\n", mtd->name);
+               return -EIO;
+       }
+
+       return 0;
+}
+
+/**
+ * __mtdsplit_parse_jimage - scan partition and create kernel + rootfs parts
+ *
+ * @find_header: function to call for a block of data that will return offset
+ *      of a valid jImage header if found
+ */
+static int __mtdsplit_parse_jimage(struct mtd_info *master,
+                                  const struct mtd_partition **pparts,
+                                  struct mtd_part_parser_data *data,
+                                  ssize_t (*find_header)(u_char *buf, size_t len))
+{
+       struct mtd_partition *parts;
+       u_char *buf;
+       int nr_parts;
+       size_t offset;
+       size_t jimage_offset;
+       size_t jimage_size = 0;
+       size_t rootfs_offset;
+       size_t rootfs_size = 0;
+       int jimage_part, rf_part;
+       int ret;
+       enum mtdsplit_part_type type;
+
+       nr_parts = 2;
+       parts = kzalloc(nr_parts * sizeof(*parts), GFP_KERNEL);
+       if (!parts)
+               return -ENOMEM;
+
+       buf = vmalloc(MAX_HEADER_LEN);
+       if (!buf) {
+               ret = -ENOMEM;
+               goto err_free_parts;
+       }
+
+       /* find jImage on erase block boundaries */
+       for (offset = 0; offset < master->size; offset += master->erasesize) {
+               struct jimage_header *header;
+
+               jimage_size = 0;
+
+               ret = read_jimage_header(master, offset, buf, MAX_HEADER_LEN);
+               if (ret)
+                       continue;
+
+               ret = find_header(buf, MAX_HEADER_LEN);
+               if (ret < 0) {
+                       pr_debug("no valid jImage found in \"%s\" at offset %llx\n",
+                                master->name, (unsigned long long) offset);
+                       continue;
+               }
+               header = (struct jimage_header *)(buf + ret);
+
+               jimage_size = sizeof(*header) + header->sch2_image_len + ret;
+               if ((offset + jimage_size) > master->size) {
+                       pr_debug("jImage exceeds MTD device \"%s\"\n",
+                                master->name);
+                       continue;
+               }
+               break;
+       }
+
+       if (jimage_size == 0) {
+               pr_debug("no jImage found in \"%s\"\n", master->name);
+               ret = -ENODEV;
+               goto err_free_buf;
+       }
+
+       jimage_offset = offset;
+
+       if (jimage_offset == 0) {
+               jimage_part = 0;
+               rf_part = 1;
+
+               /* find the roots after the jImage */
+               ret = mtd_find_rootfs_from(master, jimage_offset + jimage_size,
+                                          master->size, &rootfs_offset, &type);
+               if (ret) {
+                       pr_debug("no rootfs after jImage in \"%s\"\n",
+                                master->name);
+                       goto err_free_buf;
+               }
+
+               rootfs_size = master->size - rootfs_offset;
+               jimage_size = rootfs_offset - jimage_offset;
+       } else {
+               rf_part = 0;
+               jimage_part = 1;
+
+               /* check rootfs presence at offset 0 */
+               ret = mtd_check_rootfs_magic(master, 0, &type);
+               if (ret) {
+                       pr_debug("no rootfs before jImage in \"%s\"\n",
+                                master->name);
+                       goto err_free_buf;
+               }
+
+               rootfs_offset = 0;
+               rootfs_size = jimage_offset;
+       }
+
+       if (rootfs_size == 0) {
+               pr_debug("no rootfs found in \"%s\"\n", master->name);
+               ret = -ENODEV;
+               goto err_free_buf;
+       }
+
+       parts[jimage_part].name = KERNEL_PART_NAME;
+       parts[jimage_part].offset = jimage_offset;
+       parts[jimage_part].size = jimage_size;
+
+       if (type == MTDSPLIT_PART_TYPE_UBI)
+               parts[rf_part].name = UBI_PART_NAME;
+       else
+               parts[rf_part].name = ROOTFS_PART_NAME;
+       parts[rf_part].offset = rootfs_offset;
+       parts[rf_part].size = rootfs_size;
+
+       vfree(buf);
+
+       *pparts = parts;
+       return nr_parts;
+
+err_free_buf:
+       vfree(buf);
+
+err_free_parts:
+       kfree(parts);
+       return ret;
+}
+
+static ssize_t jimage_verify_default(u_char *buf, size_t len)
+{
+       struct jimage_header *header = (struct jimage_header *)buf;
+
+       /* default sanity checks */
+       if (header->stag_magic != STAG_MAGIC) {
+               pr_debug("invalid jImage stag header magic: %04x\n",
+                        header->stag_magic);
+               return -EINVAL;
+       }
+       if (header->sch2_magic != SCH2_MAGIC) {
+               pr_debug("invalid jImage sch2 header magic: %04x\n",
+                        header->stag_magic);
+               return -EINVAL;
+       }
+       if (header->stag_cmark != header->stag_id) {
+               pr_debug("invalid jImage stag header cmark: %02x\n",
+                        header->stag_magic);
+               return -EINVAL;
+       }
+       if (header->stag_id != STAG_ID) {
+               pr_debug("invalid jImage stag header id: %02x\n",
+                        header->stag_magic);
+               return -EINVAL;
+       }
+       if (header->sch2_version != SCH2_VER) {
+               pr_debug("invalid jImage sch2 header version: %02x\n",
+                        header->stag_magic);
+               return -EINVAL;
+       }
+
+       return 0;
+}
+
+static int
+mtdsplit_jimage_parse_generic(struct mtd_info *master,
+                             const struct mtd_partition **pparts,
+                             struct mtd_part_parser_data *data)
+{
+       return __mtdsplit_parse_jimage(master, pparts, data,
+                                     jimage_verify_default);
+}
+
+static struct mtd_part_parser jimage_generic_parser = {
+       .owner = THIS_MODULE,
+       .name = "jimage-fw",
+       .parse_fn = mtdsplit_jimage_parse_generic,
+       .type = MTD_PARSER_TYPE_FIRMWARE,
+};
+
+/**************************************************
+ * Init
+ **************************************************/
+
+static int __init mtdsplit_jimage_init(void)
+{
+       register_mtd_parser(&jimage_generic_parser);
+
+       return 0;
+}
+
+module_init(mtdsplit_jimage_init);