From 439d497a13c73a9ffa5f5a9a2575d1ecc7501858 Mon Sep 17 00:00:00 2001 From: vvb2060 Date: Sat, 8 May 2021 22:32:51 +0800 Subject: [PATCH] boot image header v4 --- native/jni/magiskboot/bootimg.cpp | 13 +++- native/jni/magiskboot/bootimg.hpp | 119 +++++++++++++++++++++++++++++- 2 files changed, 128 insertions(+), 4 deletions(-) diff --git a/native/jni/magiskboot/bootimg.cpp b/native/jni/magiskboot/bootimg.cpp index cdef1d7bf..71336f19d 100644 --- a/native/jni/magiskboot/bootimg.cpp +++ b/native/jni/magiskboot/bootimg.cpp @@ -247,7 +247,15 @@ void boot_img::parse_image(uint8_t *addr, format_t type) { auto hp = reinterpret_cast(addr); if (type == AOSP_VENDOR) { fprintf(stderr, "VENDOR_BOOT_HDR\n"); - hdr = new dyn_img_vnd_v3(addr); + switch (hp->header_version) { + case 4: + hdr = new dyn_img_vnd_v4(addr); + break; + case 3: + default: + hdr = new dyn_img_vnd_v3(addr); + break; + } } else if (hp->page_size >= 0x02000000) { fprintf(stderr, "PXA_BOOT_HDR\n"); hdr = new dyn_img_pxa(addr); @@ -276,6 +284,9 @@ void boot_img::parse_image(uint8_t *addr, format_t type) { case 3: hdr = new dyn_img_v3(addr); break; + case 4: + hdr = new dyn_img_v4(addr); + break; default: hdr = new dyn_img_v0(addr); break; diff --git a/native/jni/magiskboot/bootimg.hpp b/native/jni/magiskboot/bootimg.hpp index b472d2d31..4e29d0869 100644 --- a/native/jni/magiskboot/bootimg.hpp +++ b/native/jni/magiskboot/bootimg.hpp @@ -104,6 +104,8 @@ struct AvbVBMetaImageHeader { #define BOOT_ARGS_SIZE 512 #define BOOT_EXTRA_ARGS_SIZE 1024 #define VENDOR_BOOT_ARGS_SIZE 2048 +#define VENDOR_RAMDISK_NAME_SIZE 32 +#define VENDOR_RAMDISK_TABLE_ENTRY_BOARD_ID_SIZE 16 /* * +-----------------+ @@ -261,6 +263,101 @@ struct boot_img_hdr_vnd_v3 { uint64_t dtb_addr; /* physical load address for DTB image */ } __attribute__((packed)); +/* When the boot image header has a version of 4, the structure of the boot + * image is as follows: + * + * +---------------------+ + * | boot header | 4096 bytes + * +---------------------+ + * | kernel | m pages + * +---------------------+ + * | ramdisk | n pages + * +---------------------+ + * | boot signature | g pages + * +---------------------+ + * + * m = (kernel_size + 4096 - 1) / 4096 + * n = (ramdisk_size + 4096 - 1) / 4096 + * g = (signature_size + 4096 - 1) / 4096 + * + * Note that in version 4 of the boot image header, page size is fixed at 4096 + * bytes. + * + * The structure of the vendor boot image version 4, which is required to be + * present when a version 4 boot image is used, is as follows: + * + * +------------------------+ + * | vendor boot header | o pages + * +------------------------+ + * | vendor ramdisk section | p pages + * +------------------------+ + * | dtb | q pages + * +------------------------+ + * | vendor ramdisk table | r pages + * +------------------------+ + * | bootconfig | s pages + * +------------------------+ + * + * o = (2128 + page_size - 1) / page_size + * p = (vendor_ramdisk_size + page_size - 1) / page_size + * q = (dtb_size + page_size - 1) / page_size + * r = (vendor_ramdisk_table_size + page_size - 1) / page_size + * s = (vendor_bootconfig_size + page_size - 1) / page_size + * + * Note that in version 4 of the vendor boot image, multiple vendor ramdisks can + * be included in the vendor boot image. The bootloader can select a subset of + * ramdisks to load at runtime. To help the bootloader select the ramdisks, each + * ramdisk is tagged with a type tag and a set of hardware identifiers + * describing the board, soc or platform that this ramdisk is intended for. + * + * The vendor ramdisk section is consist of multiple ramdisk images concatenated + * one after another, and vendor_ramdisk_size is the size of the section, which + * is the total size of all the ramdisks included in the vendor boot image. + * + * The vendor ramdisk table holds the size, offset, type, name and hardware + * identifiers of each ramdisk. The type field denotes the type of its content. + * The vendor ramdisk names are unique. The hardware identifiers are specified + * in the board_id field in each table entry. The board_id field is consist of a + * vector of unsigned integer words, and the encoding scheme is defined by the + * hardware vendor. + * + * For the different type of ramdisks, there are: + * - VENDOR_RAMDISK_TYPE_NONE indicates the value is unspecified. + * - VENDOR_RAMDISK_TYPE_PLATFORM ramdisks contain platform specific bits, so + * the bootloader should always load these into memory. + * - VENDOR_RAMDISK_TYPE_RECOVERY ramdisks contain recovery resources, so + * the bootloader should load these when booting into recovery. + * - VENDOR_RAMDISK_TYPE_DLKM ramdisks contain dynamic loadable kernel + * modules. + * + * Version 4 of the vendor boot image also adds a bootconfig section to the end + * of the image. This section contains Boot Configuration parameters known at + * build time. The bootloader is responsible for placing this section directly + * after the generic ramdisk, followed by the bootconfig trailer, before + * entering the kernel. + */ +struct boot_img_hdr_v4 : public boot_img_hdr_v3 { + uint32_t signature_size; /* size in bytes */ +} __attribute__((packed)); + +struct boot_img_hdr_vnd_v4 : public boot_img_hdr_vnd_v3 { + uint32_t vendor_ramdisk_table_size; /* size in bytes for the vendor ramdisk table */ + uint32_t vendor_ramdisk_table_entry_num; /* number of entries in the vendor ramdisk table */ + uint32_t vendor_ramdisk_table_entry_size; /* size in bytes for a vendor ramdisk table entry */ + uint32_t bootconfig_size; /* size in bytes for the bootconfig section */ +} __attribute__((packed)); + +struct vendor_ramdisk_table_entry_v4 { + uint32_t ramdisk_size; /* size in bytes for the ramdisk image */ + uint32_t ramdisk_offset; /* offset to the ramdisk image in vendor ramdisk section */ + uint32_t ramdisk_type; /* type of the ramdisk */ + uint8_t ramdisk_name[VENDOR_RAMDISK_NAME_SIZE]; /* asciiz ramdisk name */ + + // Hardware identifiers describing the board, soc or platform which this + // ramdisk is intended to be loaded on. + uint32_t board_id[VENDOR_RAMDISK_TABLE_ENTRY_BOARD_ID_SIZE]; +} __attribute__((packed)); + /******************************* * Polymorphic Universal Header *******************************/ @@ -310,8 +407,10 @@ protected: // Main header could be either AOSP or PXA boot_img_hdr_v2 *v2_hdr; /* AOSP v2 header */ boot_img_hdr_v3 *v3_hdr; /* AOSP v3 header */ + boot_img_hdr_v4 *v4_hdr; /* AOSP v4 header */ boot_img_hdr_pxa *hdr_pxa; /* Samsung PXA header */ - boot_img_hdr_vnd_v3 *vnd; /* AOSP vendor v3 header */ + boot_img_hdr_vnd_v3 *v3_vnd; /* AOSP vendor v3 header */ + boot_img_hdr_vnd_v4 *v4_vnd; /* AOSP vendor v4 header */ void *raw; /* Raw pointer */ }; @@ -415,7 +514,7 @@ private: }; #undef impl_val -#define impl_val(name) __impl_val(name, vnd) +#define impl_val(name) __impl_val(name, v3_vnd) struct dyn_img_vnd_v3 : public dyn_img_hdr { impl_cls(vnd_v3) @@ -431,7 +530,21 @@ struct dyn_img_vnd_v3 : public dyn_img_hdr { size_t hdr_space() override { auto sz = page_size(); return do_align(hdr_size(), sz); } // Make API compatible - char *extra_cmdline() override { return &vnd->cmdline[BOOT_ARGS_SIZE]; } + char *extra_cmdline() override { return &v3_vnd->cmdline[BOOT_ARGS_SIZE]; } +}; + +#undef impl_val +#define impl_val(name) __impl_val(name, v4_hdr) + +struct dyn_img_v4 : public dyn_img_v3 { + impl_cls(v4) +}; + +#undef impl_val +#define impl_val(name) __impl_val(name, v4_vnd) + +struct dyn_img_vnd_v4 : public dyn_img_vnd_v3 { + impl_cls(vnd_v4) }; #undef __impl_cls