kernel/3.10: add partition parser for uImage firmwares

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>

SVN-Revision: 38113

1 files changed, 291 insertions, 0 deletions

diff --git a/target/linux/generic/files/drivers/mtd/mtdsplit_uimage.c b/target/linux/generic/files/drivers/mtd/mtdsplit_uimage.c
new file mode 100644
index 0000000..5737065
--- /dev/null
+++ b/target/linux/generic/files/drivers/mtd/mtdsplit_uimage.c
@@ -0,0 +1,291 @@
+/*
+ *  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 IH_MAGIC	0x27051956	/* Image Magic Number		*/
+#define IH_NMLEN		32	/* Image Name Length		*/
+
+#define IH_OS_LINUX		5	/* Linux	*/
+
+#define IH_TYPE_KERNEL		2	/* OS Kernel Image		*/
+#define IH_TYPE_FILESYSTEM	7	/* Filesystem Image		*/
+
+/*
+ * Legacy format image header,
+ * all data in network byte order (aka natural aka bigendian).
+ */
+struct uimage_header {
+	uint32_t	ih_magic;	/* Image Header Magic Number	*/
+	uint32_t	ih_hcrc;	/* Image Header CRC Checksum	*/
+	uint32_t	ih_time;	/* Image Creation Timestamp	*/
+	uint32_t	ih_size;	/* Image Data Size		*/
+	uint32_t	ih_load;	/* Data	 Load  Address		*/
+	uint32_t	ih_ep;		/* Entry Point Address		*/
+	uint32_t	ih_dcrc;	/* Image Data CRC Checksum	*/
+	uint8_t		ih_os;		/* Operating System		*/
+	uint8_t		ih_arch;	/* CPU architecture		*/
+	uint8_t		ih_type;	/* Image Type			*/
+	uint8_t		ih_comp;	/* Compression Type		*/
+	uint8_t		ih_name[IH_NMLEN];	/* Image Name		*/
+};
+
+static int
+read_uimage_header(struct mtd_info *mtd, size_t offset,
+		   struct uimage_header *header)
+{
+	size_t header_len;
+	size_t retlen;
+	int ret;
+
+	header_len = sizeof(*header);
+	ret = mtd_read(mtd, offset, header_len, &retlen,
+		       (unsigned char *) header);
+	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;
+}
+
+static int __mtdsplit_parse_uimage(struct mtd_info *master,
+				   struct mtd_partition **pparts,
+				   struct mtd_part_parser_data *data,
+				   bool (*verify)(struct uimage_header *hdr))
+{
+	struct mtd_partition *parts;
+	struct uimage_header *header;
+	int nr_parts;
+	size_t offset;
+	size_t uimage_offset;
+	size_t uimage_size = 0;
+	size_t rootfs_offset;
+	size_t rootfs_size = 0;
+	int uimage_part, rf_part;
+	int ret;
+
+	nr_parts = 2;
+	parts = kzalloc(nr_parts * sizeof(*parts), GFP_KERNEL);
+	if (!parts)
+		return -ENOMEM;
+
+	header = vmalloc(sizeof(*header));
+	if (!header) {
+		ret = -ENOMEM;
+		goto err_free_parts;
+	}
+
+	/* find uImage on erase block boundaries */
+	for (offset = 0; offset < master->size; offset += master->erasesize) {
+		uimage_size = 0;
+
+		ret = read_uimage_header(master, offset, header);
+		if (ret)
+			continue;
+
+		if (!verify(header)) {
+			pr_debug("no valid uImage found in \"%s\" at offset %llx\n",
+				 master->name, (unsigned long long) offset);
+			continue;
+		}
+
+		uimage_size = sizeof(*header) + be32_to_cpu(header->ih_size);
+		if ((offset + uimage_size) > master->size) {
+			pr_debug("uImage exceeds MTD device \"%s\"\n",
+				 master->name);
+			continue;
+		}
+		break;
+	}
+
+	if (uimage_size == 0) {
+		pr_debug("no uImage found in \"%s\"\n", master->name);
+		ret = -ENODEV;
+		goto err_free_header;
+	}
+
+	uimage_offset = offset;
+
+	if (uimage_offset == 0) {
+		uimage_part = 0;
+		rf_part = 1;
+
+		/* find the roots after the uImage */
+		ret = mtd_find_rootfs_from(master,
+					   uimage_offset + uimage_size,
+					   master->size,
+					   &rootfs_offset);
+		if (ret) {
+			pr_debug("no rootfs after uImage in \"%s\"\n",
+				 master->name);
+			goto err_free_header;
+		}
+
+		rootfs_size = master->size - rootfs_offset;
+		uimage_size = rootfs_offset - uimage_offset;
+	} else {
+		rf_part = 0;
+		uimage_part = 1;
+
+		/* check rootfs presence at offset 0 */
+		ret = mtd_check_rootfs_magic(master, 0);
+		if (ret) {
+			pr_debug("no rootfs before uImage in \"%s\"\n",
+				 master->name);
+			goto err_free_header;
+		}
+
+		rootfs_offset = 0;
+		rootfs_size = uimage_offset;
+	}
+
+	if (rootfs_size == 0) {
+		pr_debug("no rootfs found in \"%s\"\n", master->name);
+		ret = -ENODEV;
+		goto err_free_header;
+	}
+
+	parts[uimage_part].name = KERNEL_PART_NAME;
+	parts[uimage_part].offset = uimage_offset;
+	parts[uimage_part].size = uimage_size;
+
+	parts[rf_part].name = ROOTFS_PART_NAME;
+	parts[rf_part].offset = rootfs_offset;
+	parts[rf_part].size = rootfs_size;
+
+	vfree(header);
+
+	*pparts = parts;
+	return nr_parts;
+
+err_free_header:
+	vfree(header);
+
+err_free_parts:
+	kfree(parts);
+	return ret;
+}
+
+static bool uimage_verify_default(struct uimage_header *header)
+{
+	/* default sanity checks */
+	if (be32_to_cpu(header->ih_magic) != IH_MAGIC) {
+		pr_debug("invalid uImage magic: %08x\n",
+			 be32_to_cpu(header->ih_magic));
+		return false;
+	}
+
+	if (header->ih_os != IH_OS_LINUX) {
+		pr_debug("invalid uImage OS: %08x\n",
+			 be32_to_cpu(header->ih_os));
+		return false;
+	}
+
+	if (header->ih_type != IH_TYPE_KERNEL) {
+		pr_debug("invalid uImage type: %08x\n",
+			 be32_to_cpu(header->ih_type));
+		return false;
+	}
+
+	return true;
+}
+
+static int
+mtdsplit_uimage_parse_generic(struct mtd_info *master,
+			      struct mtd_partition **pparts,
+			      struct mtd_part_parser_data *data)
+{
+	return __mtdsplit_parse_uimage(master, pparts, data,
+				      uimage_verify_default);
+}
+
+static struct mtd_part_parser uimage_generic_parser = {
+	.owner = THIS_MODULE,
+	.name = "uimage-fw",
+	.parse_fn = mtdsplit_uimage_parse_generic,
+	.type = MTD_PARSER_TYPE_FIRMWARE,
+};
+
+#define FW_MAGIC_WNR2000V3	0x32303033
+#define FW_MAGIC_WNR612V2	0x32303631
+#define FW_MAGIC_WNDR3700	0x33373030
+#define FW_MAGIC_WNDR3700V2	0x33373031
+
+static bool uimage_verify_wndr3700(struct uimage_header *header)
+{
+	switch be32_to_cpu(header->ih_magic) {
+	case FW_MAGIC_WNR612V2:
+	case FW_MAGIC_WNR2000V3:
+	case FW_MAGIC_WNDR3700:
+	case FW_MAGIC_WNDR3700V2:
+		break;
+	default:
+		return false;
+	}
+
+	if (header->ih_os != IH_OS_LINUX ||
+	    header->ih_type != IH_TYPE_FILESYSTEM)
+		return false;
+
+	return true;
+}
+
+static int
+mtdsplit_uimage_parse_netgear(struct mtd_info *master,
+			      struct mtd_partition **pparts,
+			      struct mtd_part_parser_data *data)
+{
+	return __mtdsplit_parse_uimage(master, pparts, data,
+				      uimage_verify_wndr3700);
+}
+
+static struct mtd_part_parser uimage_netgear_parser = {
+	.owner = THIS_MODULE,
+	.name = "netgear-fw",
+	.parse_fn = mtdsplit_uimage_parse_netgear,
+	.type = MTD_PARSER_TYPE_FIRMWARE,
+};
+
+static int mtdsplit_uimage_init(void)
+{
+	int ret;
+
+	ret = register_mtd_parser(&uimage_generic_parser);
+	if (ret)
+		return ret;
+
+	ret = register_mtd_parser(&uimage_netgear_parser);
+	if (ret)
+		goto err_unregister_generic;
+
+	return 0;
+
+err_unregister_generic:
+	deregister_mtd_parser(&uimage_generic_parser);
+	return ret;
+}
+
+module_init(mtdsplit_uimage_init);
\ No newline at end of file