| 1 | /* |
| 2 | * Copyright (C) 2011 Gabor Juhos <juhosg@openwrt.org> |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or modify it |
| 5 | * under the terms of the GNU General Public License version 2 as published |
| 6 | * by the Free Software Foundation. |
| 7 | * |
| 8 | */ |
| 9 | |
| 10 | #include <linux/kernel.h> |
| 11 | #include <linux/module.h> |
| 12 | #include <linux/slab.h> |
| 13 | #include <linux/vmalloc.h> |
| 14 | #include <linux/magic.h> |
| 15 | |
| 16 | #include <linux/mtd/mtd.h> |
| 17 | #include <linux/mtd/partitions.h> |
| 18 | |
| 19 | #define TPLINK_NUM_PARTS 5 |
| 20 | #define TPLINK_HEADER_V1 0x01000000 |
| 21 | #define MD5SUM_LEN 16 |
| 22 | |
| 23 | #define TPLINK_ART_LEN 0x10000 |
| 24 | #define TPLINK_KERNEL_OFFS 0x20000 |
| 25 | |
| 26 | struct tplink_fw_header { |
| 27 | uint32_t version; /* header version */ |
| 28 | char vendor_name[24]; |
| 29 | char fw_version[36]; |
| 30 | uint32_t hw_id; /* hardware id */ |
| 31 | uint32_t hw_rev; /* hardware revision */ |
| 32 | uint32_t unk1; |
| 33 | uint8_t md5sum1[MD5SUM_LEN]; |
| 34 | uint32_t unk2; |
| 35 | uint8_t md5sum2[MD5SUM_LEN]; |
| 36 | uint32_t unk3; |
| 37 | uint32_t kernel_la; /* kernel load address */ |
| 38 | uint32_t kernel_ep; /* kernel entry point */ |
| 39 | uint32_t fw_length; /* total length of the firmware */ |
| 40 | uint32_t kernel_ofs; /* kernel data offset */ |
| 41 | uint32_t kernel_len; /* kernel data length */ |
| 42 | uint32_t rootfs_ofs; /* rootfs data offset */ |
| 43 | uint32_t rootfs_len; /* rootfs data length */ |
| 44 | uint32_t boot_ofs; /* bootloader data offset */ |
| 45 | uint32_t boot_len; /* bootloader data length */ |
| 46 | uint8_t pad[360]; |
| 47 | } __attribute__ ((packed)); |
| 48 | |
| 49 | static struct tplink_fw_header * |
| 50 | tplink_read_header(struct mtd_info *mtd, size_t offset) |
| 51 | { |
| 52 | struct tplink_fw_header *header; |
| 53 | size_t header_len; |
| 54 | size_t retlen; |
| 55 | int ret; |
| 56 | u32 t; |
| 57 | |
| 58 | header = vmalloc(sizeof(*header)); |
| 59 | if (!header) |
| 60 | goto err; |
| 61 | |
| 62 | header_len = sizeof(struct tplink_fw_header); |
| 63 | ret = mtd_read(mtd, offset, header_len, &retlen, |
| 64 | (unsigned char *) header); |
| 65 | if (ret) |
| 66 | goto err_free_header; |
| 67 | |
| 68 | if (retlen != header_len) |
| 69 | goto err_free_header; |
| 70 | |
| 71 | /* sanity checks */ |
| 72 | t = be32_to_cpu(header->version); |
| 73 | if (t != TPLINK_HEADER_V1) |
| 74 | goto err_free_header; |
| 75 | |
| 76 | t = be32_to_cpu(header->kernel_ofs); |
| 77 | if (t != header_len) |
| 78 | goto err_free_header; |
| 79 | |
| 80 | return header; |
| 81 | |
| 82 | err_free_header: |
| 83 | vfree(header); |
| 84 | err: |
| 85 | return NULL; |
| 86 | } |
| 87 | |
| 88 | static int tplink_check_rootfs_magic(struct mtd_info *mtd, size_t offset) |
| 89 | { |
| 90 | u32 magic; |
| 91 | size_t retlen; |
| 92 | int ret; |
| 93 | |
| 94 | ret = mtd_read(mtd, offset, sizeof(magic), &retlen, |
| 95 | (unsigned char *) &magic); |
| 96 | if (ret) |
| 97 | return ret; |
| 98 | |
| 99 | if (retlen != sizeof(magic)) |
| 100 | return -EIO; |
| 101 | |
| 102 | if (le32_to_cpu(magic) != SQUASHFS_MAGIC && |
| 103 | magic != 0x19852003) |
| 104 | return -EINVAL; |
| 105 | |
| 106 | return 0; |
| 107 | } |
| 108 | |
| 109 | static int tplink_parse_partitions(struct mtd_info *master, |
| 110 | struct mtd_partition **pparts, |
| 111 | struct mtd_part_parser_data *data) |
| 112 | { |
| 113 | struct mtd_partition *parts; |
| 114 | struct tplink_fw_header *header; |
| 115 | int nr_parts; |
| 116 | size_t offset; |
| 117 | size_t art_offset; |
| 118 | size_t rootfs_offset; |
| 119 | size_t squashfs_offset; |
| 120 | int ret; |
| 121 | |
| 122 | nr_parts = TPLINK_NUM_PARTS; |
| 123 | parts = kzalloc(nr_parts * sizeof(struct mtd_partition), GFP_KERNEL); |
| 124 | if (!parts) { |
| 125 | ret = -ENOMEM; |
| 126 | goto err; |
| 127 | } |
| 128 | |
| 129 | offset = TPLINK_KERNEL_OFFS; |
| 130 | |
| 131 | header = tplink_read_header(master, offset); |
| 132 | if (!header) { |
| 133 | pr_notice("%s: no TP-Link header found\n", master->name); |
| 134 | ret = -ENODEV; |
| 135 | goto err_free_parts; |
| 136 | } |
| 137 | |
| 138 | squashfs_offset = offset + sizeof(struct tplink_fw_header) + |
| 139 | be32_to_cpu(header->kernel_len); |
| 140 | |
| 141 | ret = tplink_check_rootfs_magic(master, squashfs_offset); |
| 142 | if (ret == 0) |
| 143 | rootfs_offset = squashfs_offset; |
| 144 | else |
| 145 | rootfs_offset = offset + be32_to_cpu(header->rootfs_ofs); |
| 146 | |
| 147 | art_offset = master->size - TPLINK_ART_LEN; |
| 148 | |
| 149 | parts[0].name = "u-boot"; |
| 150 | parts[0].offset = 0; |
| 151 | parts[0].size = offset; |
| 152 | parts[0].mask_flags = MTD_WRITEABLE; |
| 153 | |
| 154 | parts[1].name = "kernel"; |
| 155 | parts[1].offset = offset; |
| 156 | parts[1].size = rootfs_offset - offset; |
| 157 | |
| 158 | parts[2].name = "rootfs"; |
| 159 | parts[2].offset = rootfs_offset; |
| 160 | parts[2].size = art_offset - rootfs_offset; |
| 161 | |
| 162 | parts[3].name = "art"; |
| 163 | parts[3].offset = art_offset; |
| 164 | parts[3].size = TPLINK_ART_LEN; |
| 165 | parts[3].mask_flags = MTD_WRITEABLE; |
| 166 | |
| 167 | parts[4].name = "firmware"; |
| 168 | parts[4].offset = offset; |
| 169 | parts[4].size = art_offset - offset; |
| 170 | |
| 171 | vfree(header); |
| 172 | |
| 173 | *pparts = parts; |
| 174 | return nr_parts; |
| 175 | |
| 176 | err_free_parts: |
| 177 | kfree(parts); |
| 178 | err: |
| 179 | *pparts = NULL; |
| 180 | return ret; |
| 181 | } |
| 182 | |
| 183 | static struct mtd_part_parser tplink_parser = { |
| 184 | .owner = THIS_MODULE, |
| 185 | .parse_fn = tplink_parse_partitions, |
| 186 | .name = "tp-link", |
| 187 | }; |
| 188 | |
| 189 | static int __init tplink_parser_init(void) |
| 190 | { |
| 191 | return register_mtd_parser(&tplink_parser); |
| 192 | } |
| 193 | |
| 194 | module_init(tplink_parser_init); |
| 195 | |
| 196 | MODULE_LICENSE("GPL v2"); |
| 197 | MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>"); |
| 198 | |
