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Diffstat (limited to 'gpt-utils/gpt-utils.cpp')
| -rw-r--r-- | gpt-utils/gpt-utils.cpp | 1519 |
1 files changed, 1519 insertions, 0 deletions
diff --git a/gpt-utils/gpt-utils.cpp b/gpt-utils/gpt-utils.cpp new file mode 100644 index 0000000..58fc93a --- /dev/null +++ b/gpt-utils/gpt-utils.cpp @@ -0,0 +1,1519 @@ +/* + * Copyright (c) 2013,2016,2020 The Linux Foundation. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials provided + * with the distribution. + * * Neither the name of The Linux Foundation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS + * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR + * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, + * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE + * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN + * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#define _LARGEFILE64_SOURCE /* enable lseek64() */ + +/****************************************************************************** + * INCLUDE SECTION + ******************************************************************************/ +#include <fcntl.h> +#include <string.h> +#include <errno.h> +#include <sys/stat.h> +#include <sys/ioctl.h> +#include <unistd.h> +#include <linux/fs.h> +#include <limits.h> +#include <dirent.h> +#include <linux/kernel.h> +#include <map> +#include <vector> +#include <string> +#ifndef __STDC_FORMAT_MACROS +#define __STDC_FORMAT_MACROS +#endif +#include <inttypes.h> + + +#define LOG_TAG "gpt-utils" +#include <log/log.h> +#include <cutils/properties.h> +#include "gpt-utils.h" +#include <zlib.h> +#include <endian.h> + + +/****************************************************************************** + * DEFINE SECTION + ******************************************************************************/ +#define BLK_DEV_FILE "/dev/block/mmcblk0" +/* list the names of the backed-up partitions to be swapped */ +/* extension used for the backup partitions - tzbak, abootbak, etc. */ +#define BAK_PTN_NAME_EXT "bak" +#define XBL_PRIMARY "/dev/block/bootdevice/by-name/xbl" +#define XBL_BACKUP "/dev/block/bootdevice/by-name/xblbak" +#define XBL_AB_PRIMARY "/dev/block/bootdevice/by-name/xbl_a" +#define XBL_AB_SECONDARY "/dev/block/bootdevice/by-name/xbl_b" +/* GPT defines */ +#define MAX_LUNS 26 +//This will allow us to get the root lun path from the path to the partition. +//i.e: from /dev/block/sdaXXX get /dev/block/sda. The assumption here is that +//the boot critical luns lie between sda to sdz which is acceptable because +//only user added external disks,etc would lie beyond that limit which do not +//contain partitions that interest us here. +#define PATH_TRUNCATE_LOC (sizeof("/dev/block/sda") - 1) + +//From /dev/block/sda get just sda +#define LUN_NAME_START_LOC (sizeof("/dev/block/") - 1) +#define BOOT_LUN_A_ID 1 +#define BOOT_LUN_B_ID 2 +/****************************************************************************** + * MACROS + ******************************************************************************/ + + +#define GET_4_BYTES(ptr) ((uint32_t) *((uint8_t *)(ptr)) | \ + ((uint32_t) *((uint8_t *)(ptr) + 1) << 8) | \ + ((uint32_t) *((uint8_t *)(ptr) + 2) << 16) | \ + ((uint32_t) *((uint8_t *)(ptr) + 3) << 24)) + +#define GET_8_BYTES(ptr) ((uint64_t) *((uint8_t *)(ptr)) | \ + ((uint64_t) *((uint8_t *)(ptr) + 1) << 8) | \ + ((uint64_t) *((uint8_t *)(ptr) + 2) << 16) | \ + ((uint64_t) *((uint8_t *)(ptr) + 3) << 24) | \ + ((uint64_t) *((uint8_t *)(ptr) + 4) << 32) | \ + ((uint64_t) *((uint8_t *)(ptr) + 5) << 40) | \ + ((uint64_t) *((uint8_t *)(ptr) + 6) << 48) | \ + ((uint64_t) *((uint8_t *)(ptr) + 7) << 56)) + +#define PUT_4_BYTES(ptr, y) *((uint8_t *)(ptr)) = (y) & 0xff; \ + *((uint8_t *)(ptr) + 1) = ((y) >> 8) & 0xff; \ + *((uint8_t *)(ptr) + 2) = ((y) >> 16) & 0xff; \ + *((uint8_t *)(ptr) + 3) = ((y) >> 24) & 0xff; + +/****************************************************************************** + * TYPES + ******************************************************************************/ +using namespace std; +enum gpt_state { + GPT_OK = 0, + GPT_BAD_SIGNATURE, + GPT_BAD_CRC +}; +//List of LUN's containing boot critical images. +//Required in the case of UFS devices +struct update_data { + char lun_list[MAX_LUNS][PATH_MAX]; + uint32_t num_valid_entries; +}; + +int32_t set_boot_lun(char *sg_dev,uint8_t boot_lun_id); +/****************************************************************************** + * FUNCTIONS + ******************************************************************************/ +/** + * ========================================================================== + * + * \brief Read/Write len bytes from/to block dev + * + * \param [in] fd block dev file descriptor (returned from open) + * \param [in] rw RW flag: 0 - read, != 0 - write + * \param [in] offset block dev offset [bytes] - RW start position + * \param [in] buf Pointer to the buffer containing the data + * \param [in] len RW size in bytes. Buf must be at least that big + * + * \return 0 on success + * + * ========================================================================== + */ +static int blk_rw(int fd, int rw, int64_t offset, uint8_t *buf, unsigned len) +{ + int r; + + if (lseek64(fd, offset, SEEK_SET) < 0) { + fprintf(stderr, "block dev lseek64 %" PRIi64 " failed: %s\n", offset, + strerror(errno)); + return -1; + } + + if (rw) + r = write(fd, buf, len); + else + r = read(fd, buf, len); + + if (r < 0) + fprintf(stderr, "block dev %s failed: %s\n", rw ? "write" : "read", + strerror(errno)); + else + r = 0; + + return r; +} + + + +/** + * ========================================================================== + * + * \brief Search within GPT for partition entry with the given name + * or it's backup twin (name-bak). + * + * \param [in] ptn_name Partition name to seek + * \param [in] pentries_start Partition entries array start pointer + * \param [in] pentries_end Partition entries array end pointer + * \param [in] pentry_size Single partition entry size [bytes] + * + * \return First partition entry pointer that matches the name or NULL + * + * ========================================================================== + */ +static uint8_t *gpt_pentry_seek(const char *ptn_name, + const uint8_t *pentries_start, + const uint8_t *pentries_end, + uint32_t pentry_size) +{ + char *pentry_name; + unsigned len = strlen(ptn_name); + unsigned i; + char name8[MAX_GPT_NAME_SIZE] = {0}; // initialize with null + + for (pentry_name = (char *) (pentries_start + PARTITION_NAME_OFFSET); + pentry_name < (char *) pentries_end; + pentry_name += pentry_size) { + + /* Partition names in GPT are UTF-16 - ignoring UTF-16 2nd byte */ + for (i = 0; i < sizeof(name8) / 2; i++) + name8[i] = pentry_name[i * 2]; + name8[i] = '\0'; + + if (!strncmp(ptn_name, name8, len)) { + if (name8[len] == 0 || !strcmp(&name8[len], BAK_PTN_NAME_EXT)) + return (uint8_t *) (pentry_name - PARTITION_NAME_OFFSET); + } + } + + return NULL; +} + + + +/** + * ========================================================================== + * + * \brief Swaps boot chain in GPT partition entries array + * + * \param [in] pentries_start Partition entries array start + * \param [in] pentries_end Partition entries array end + * \param [in] pentry_size Single partition entry size + * + * \return 0 on success, 1 if no backup partitions found + * + * ========================================================================== + */ +static int gpt_boot_chain_swap(const uint8_t *pentries_start, + const uint8_t *pentries_end, + uint32_t pentry_size) +{ + const char ptn_swap_list[][MAX_GPT_NAME_SIZE] = { PTN_SWAP_LIST }; + + int backup_not_found = 1; + unsigned i; + + for (i = 0; i < ARRAY_SIZE(ptn_swap_list); i++) { + uint8_t *ptn_entry; + uint8_t *ptn_bak_entry; + uint8_t ptn_swap[PTN_ENTRY_SIZE]; + //Skip the xbl partition on UFS devices. That is handled + //seperately. + if (gpt_utils_is_ufs_device() && !strncmp(ptn_swap_list[i], + PTN_XBL, + strlen(PTN_XBL))) + continue; + + ptn_entry = gpt_pentry_seek(ptn_swap_list[i], pentries_start, + pentries_end, pentry_size); + if (ptn_entry == NULL) + continue; + + ptn_bak_entry = gpt_pentry_seek(ptn_swap_list[i], + ptn_entry + pentry_size, pentries_end, pentry_size); + if (ptn_bak_entry == NULL) { + fprintf(stderr, "'%s' partition not backup - skip safe update\n", + ptn_swap_list[i]); + continue; + } + + /* swap primary <-> backup partition entries */ + memcpy(ptn_swap, ptn_entry, PTN_ENTRY_SIZE); + memcpy(ptn_entry, ptn_bak_entry, PTN_ENTRY_SIZE); + memcpy(ptn_bak_entry, ptn_swap, PTN_ENTRY_SIZE); + backup_not_found = 0; + } + + return backup_not_found; +} + + + +/** + * ========================================================================== + * + * \brief Sets secondary GPT boot chain + * + * \param [in] fd block dev file descriptor + * \param [in] boot Boot chain to switch to + * + * \return 0 on success + * + * ========================================================================== + */ +static int gpt2_set_boot_chain(int fd, enum boot_chain boot) +{ + int64_t gpt2_header_offset; + uint64_t pentries_start_offset; + uint32_t gpt_header_size; + uint32_t pentry_size; + uint32_t pentries_array_size; + + uint8_t *gpt_header = NULL; + uint8_t *pentries = NULL; + uint32_t crc; + uint32_t crc_zero; + uint32_t blk_size = 0; + int r; + + + crc_zero = crc32(0L, Z_NULL, 0); + if (ioctl(fd, BLKSSZGET, &blk_size) != 0) { + fprintf(stderr, "Failed to get GPT device block size: %s\n", + strerror(errno)); + r = -1; + goto EXIT; + } + gpt_header = (uint8_t*)malloc(blk_size); + if (!gpt_header) { + fprintf(stderr, "Failed to allocate memory to hold GPT block\n"); + r = -1; + goto EXIT; + } + gpt2_header_offset = lseek64(fd, 0, SEEK_END) - blk_size; + if (gpt2_header_offset < 0) { + fprintf(stderr, "Getting secondary GPT header offset failed: %s\n", + strerror(errno)); + r = -1; + goto EXIT; + } + + /* Read primary GPT header from block dev */ + r = blk_rw(fd, 0, blk_size, gpt_header, blk_size); + + if (r) { + fprintf(stderr, "Failed to read primary GPT header from blk dev\n"); + goto EXIT; + } + pentries_start_offset = + GET_8_BYTES(gpt_header + PENTRIES_OFFSET) * blk_size; + pentry_size = GET_4_BYTES(gpt_header + PENTRY_SIZE_OFFSET); + pentries_array_size = + GET_4_BYTES(gpt_header + PARTITION_COUNT_OFFSET) * pentry_size; + + pentries = (uint8_t *) calloc(1, pentries_array_size); + if (pentries == NULL) { + fprintf(stderr, + "Failed to alloc memory for GPT partition entries array\n"); + r = -1; + goto EXIT; + } + /* Read primary GPT partititon entries array from block dev */ + r = blk_rw(fd, 0, pentries_start_offset, pentries, pentries_array_size); + if (r) + goto EXIT; + + crc = crc32(crc_zero, pentries, pentries_array_size); + if (GET_4_BYTES(gpt_header + PARTITION_CRC_OFFSET) != crc) { + fprintf(stderr, "Primary GPT partition entries array CRC invalid\n"); + r = -1; + goto EXIT; + } + + /* Read secondary GPT header from block dev */ + r = blk_rw(fd, 0, gpt2_header_offset, gpt_header, blk_size); + if (r) + goto EXIT; + + gpt_header_size = GET_4_BYTES(gpt_header + HEADER_SIZE_OFFSET); + pentries_start_offset = + GET_8_BYTES(gpt_header + PENTRIES_OFFSET) * blk_size; + + if (boot == BACKUP_BOOT) { + r = gpt_boot_chain_swap(pentries, pentries + pentries_array_size, + pentry_size); + if (r) + goto EXIT; + } + + crc = crc32(crc_zero, pentries, pentries_array_size); + PUT_4_BYTES(gpt_header + PARTITION_CRC_OFFSET, crc); + + /* header CRC is calculated with this field cleared */ + PUT_4_BYTES(gpt_header + HEADER_CRC_OFFSET, 0); + crc = crc32(crc_zero, gpt_header, gpt_header_size); + PUT_4_BYTES(gpt_header + HEADER_CRC_OFFSET, crc); + + /* Write the modified GPT header back to block dev */ + r = blk_rw(fd, 1, gpt2_header_offset, gpt_header, blk_size); + if (!r) + /* Write the modified GPT partititon entries array back to block dev */ + r = blk_rw(fd, 1, pentries_start_offset, pentries, + pentries_array_size); + +EXIT: + if(gpt_header) + free(gpt_header); + if (pentries) + free(pentries); + return r; +} + +/** + * ========================================================================== + * + * \brief Checks GPT state (header signature and CRC) + * + * \param [in] fd block dev file descriptor + * \param [in] gpt GPT header to be checked + * \param [out] state GPT header state + * + * \return 0 on success + * + * ========================================================================== + */ +static int gpt_get_state(int fd, enum gpt_instance gpt, enum gpt_state *state) +{ + int64_t gpt_header_offset; + uint32_t gpt_header_size; + uint8_t *gpt_header = NULL; + uint32_t crc; + uint32_t crc_zero; + uint32_t blk_size = 0; + + *state = GPT_OK; + + crc_zero = crc32(0L, Z_NULL, 0); + if (ioctl(fd, BLKSSZGET, &blk_size) != 0) { + fprintf(stderr, "Failed to get GPT device block size: %s\n", + strerror(errno)); + goto error; + } + gpt_header = (uint8_t*)malloc(blk_size); + if (!gpt_header) { + fprintf(stderr, "gpt_get_state:Failed to alloc memory for header\n"); + goto error; + } + if (gpt == PRIMARY_GPT) + gpt_header_offset = blk_size; + else { + gpt_header_offset = lseek64(fd, 0, SEEK_END) - blk_size; + if (gpt_header_offset < 0) { + fprintf(stderr, "gpt_get_state:Seek to end of GPT part fail\n"); + goto error; + } + } + + if (blk_rw(fd, 0, gpt_header_offset, gpt_header, blk_size)) { + fprintf(stderr, "gpt_get_state: blk_rw failed\n"); + goto error; + } + if (memcmp(gpt_header, GPT_SIGNATURE, sizeof(GPT_SIGNATURE))) + *state = GPT_BAD_SIGNATURE; + gpt_header_size = GET_4_BYTES(gpt_header + HEADER_SIZE_OFFSET); + + crc = GET_4_BYTES(gpt_header + HEADER_CRC_OFFSET); + /* header CRC is calculated with this field cleared */ + PUT_4_BYTES(gpt_header + HEADER_CRC_OFFSET, 0); + if (crc32(crc_zero, gpt_header, gpt_header_size) != crc) + *state = GPT_BAD_CRC; + free(gpt_header); + return 0; +error: + if (gpt_header) + free(gpt_header); + return -1; +} + + + +/** + * ========================================================================== + * + * \brief Sets GPT header state (used to corrupt and fix GPT signature) + * + * \param [in] fd block dev file descriptor + * \param [in] gpt GPT header to be checked + * \param [in] state GPT header state to set (GPT_OK or GPT_BAD_SIGNATURE) + * + * \return 0 on success + * + * ========================================================================== + */ +static int gpt_set_state(int fd, enum gpt_instance gpt, enum gpt_state state) +{ + int64_t gpt_header_offset; + uint32_t gpt_header_size; + uint8_t *gpt_header = NULL; + uint32_t crc; + uint32_t crc_zero; + uint32_t blk_size = 0; + + crc_zero = crc32(0L, Z_NULL, 0); + if (ioctl(fd, BLKSSZGET, &blk_size) != 0) { + fprintf(stderr, "Failed to get GPT device block size: %s\n", + strerror(errno)); + goto error; + } + gpt_header = (uint8_t*)malloc(blk_size); + if (!gpt_header) { + fprintf(stderr, "Failed to alloc memory for gpt header\n"); + goto error; + } + if (gpt == PRIMARY_GPT) + gpt_header_offset = blk_size; + else { + gpt_header_offset = lseek64(fd, 0, SEEK_END) - blk_size; + if (gpt_header_offset < 0) { + fprintf(stderr, "Failed to seek to end of GPT device\n"); + goto error; + } + } + if (blk_rw(fd, 0, gpt_header_offset, gpt_header, blk_size)) { + fprintf(stderr, "Failed to r/w gpt header\n"); + goto error; + } + if (state == GPT_OK) + memcpy(gpt_header, GPT_SIGNATURE, sizeof(GPT_SIGNATURE)); + else if (state == GPT_BAD_SIGNATURE) + *gpt_header = 0; + else { + fprintf(stderr, "gpt_set_state: Invalid state\n"); + goto error; + } + + gpt_header_size = GET_4_BYTES(gpt_header + HEADER_SIZE_OFFSET); + + /* header CRC is calculated with this field cleared */ + PUT_4_BYTES(gpt_header + HEADER_CRC_OFFSET, 0); + crc = crc32(crc_zero, gpt_header, gpt_header_size); + PUT_4_BYTES(gpt_header + HEADER_CRC_OFFSET, crc); + + if (blk_rw(fd, 1, gpt_header_offset, gpt_header, blk_size)) { + fprintf(stderr, "gpt_set_state: blk write failed\n"); + goto error; + } + return 0; +error: + if(gpt_header) + free(gpt_header); + return -1; +} + +int get_scsi_node_from_bootdevice(const char *bootdev_path, + char *sg_node_path, + size_t buf_size) +{ + char sg_dir_path[PATH_MAX] = {0}; + char real_path[PATH_MAX] = {0}; + DIR *scsi_dir = NULL; + struct dirent *de; + int node_found = 0; + if (!bootdev_path || !sg_node_path) { + fprintf(stderr, "%s : invalid argument\n", + __func__); + goto error; + } + if (readlink(bootdev_path, real_path, sizeof(real_path) - 1) < 0) { + fprintf(stderr, "failed to resolve link for %s(%s)\n", + bootdev_path, + strerror(errno)); + goto error; + } + if(strlen(real_path) < PATH_TRUNCATE_LOC + 1){ + fprintf(stderr, "Unrecognized path :%s:\n", + real_path); + goto error; + } + //For the safe side in case there are additional partitions on + //the XBL lun we truncate the name. + real_path[PATH_TRUNCATE_LOC] = '\0'; + if(strlen(real_path) < LUN_NAME_START_LOC + 1){ + fprintf(stderr, "Unrecognized truncated path :%s:\n", + real_path); + goto error; + } + //This will give us /dev/block/sdb/device/scsi_generic + //which contains a file sgY whose name gives us the path + //to /dev/sgY which we return + snprintf(sg_dir_path, sizeof(sg_dir_path) - 1, + "/sys/block/%s/device/scsi_generic", + &real_path[LUN_NAME_START_LOC]); + scsi_dir = opendir(sg_dir_path); + if (!scsi_dir) { + fprintf(stderr, "%s : Failed to open %s(%s)\n", + __func__, + sg_dir_path, + strerror(errno)); + goto error; + } + while((de = readdir(scsi_dir))) { + if (de->d_name[0] == '.') + continue; + else if (!strncmp(de->d_name, "sg", 2)) { + snprintf(sg_node_path, + buf_size -1, + "/dev/%s", + de->d_name); + fprintf(stderr, "%s:scsi generic node is :%s:\n", + __func__, + sg_node_path); + node_found = 1; + break; + } + } + if(!node_found) { + fprintf(stderr,"%s: Unable to locate scsi generic node\n", + __func__); + goto error; + } + closedir(scsi_dir); + return 0; +error: + if (scsi_dir) + closedir(scsi_dir); + return -1; +} + + + +//Swtich betwieen using either the primary or the backup +//boot LUN for boot. This is required since UFS boot partitions +//cannot have a backup GPT which is what we use for failsafe +//updates of the other 'critical' partitions. This function will +//not be invoked for emmc targets and on UFS targets is only required +//to be invoked for XBL. +// +//The algorithm to do this is as follows: +//- Find the real block device(eg: /dev/block/sdb) that corresponds +// to the /dev/block/bootdevice/by-name/xbl(bak) symlink +// +//- Once we have the block device 'node' name(sdb in the above example) +// use this node to to locate the scsi generic device that represents +// it by checking the file /sys/block/sdb/device/scsi_generic/sgY +// +//- Once we locate sgY we call the query ioctl on /dev/sgy to switch +//the boot lun to either LUNA or LUNB +int gpt_utils_set_xbl_boot_partition(enum boot_chain chain) +{ + struct stat st; + ///sys/block/sdX/device/scsi_generic/ + char sg_dev_node[PATH_MAX] = {0}; + uint8_t boot_lun_id = 0; + const char *boot_dev = NULL; + + if (chain == BACKUP_BOOT) { + boot_lun_id = BOOT_LUN_B_ID; + if (!stat(XBL_BACKUP, &st)) + boot_dev = XBL_BACKUP; + else if (!stat(XBL_AB_SECONDARY, &st)) + boot_dev = XBL_AB_SECONDARY; + else { + fprintf(stderr, "%s: Failed to locate secondary xbl\n", + __func__); + goto error; + } + } else if (chain == NORMAL_BOOT) { + boot_lun_id = BOOT_LUN_A_ID; + if (!stat(XBL_PRIMARY, &st)) + boot_dev = XBL_PRIMARY; + else if (!stat(XBL_AB_PRIMARY, &st)) + boot_dev = XBL_AB_PRIMARY; + else { + fprintf(stderr, "%s: Failed to locate primary xbl\n", + __func__); + goto error; + } + } else { + fprintf(stderr, "%s: Invalid boot chain id\n", __func__); + goto error; + } + //We need either both xbl and xblbak or both xbl_a and xbl_b to exist at + //the same time. If not the current configuration is invalid. + if((stat(XBL_PRIMARY, &st) || + stat(XBL_BACKUP, &st)) && + (stat(XBL_AB_PRIMARY, &st) || + stat(XBL_AB_SECONDARY, &st))) { + fprintf(stderr, "%s:primary/secondary XBL prt not found(%s)\n", + __func__, + strerror(errno)); + goto error; + } + fprintf(stderr, "%s: setting %s lun as boot lun\n", + __func__, + boot_dev); + if (get_scsi_node_from_bootdevice(boot_dev, + sg_dev_node, + sizeof(sg_dev_node))) { + fprintf(stderr, "%s: Failed to get scsi node path for xblbak\n", + __func__); + goto error; + } + /* set boot lun using /dev/sg or /dev/ufs-bsg* */ + if (set_boot_lun(sg_dev_node, boot_lun_id)) { + fprintf(stderr, "%s: Failed to set xblbak as boot partition\n", + __func__); + goto error; + } + return 0; +error: + return -1; +} + +int gpt_utils_is_ufs_device() +{ + char bootdevice[PROPERTY_VALUE_MAX] = {0}; + property_get("ro.boot.bootdevice", bootdevice, "N/A"); + if (strlen(bootdevice) < strlen(".ufshc") + 1) + return 0; + return (!strncmp(&bootdevice[strlen(bootdevice) - strlen(".ufshc")], + ".ufshc", + sizeof(".ufshc"))); +} +//dev_path is the path to the block device that contains the GPT image that +//needs to be updated. This would be the device which holds one or more critical +//boot partitions and their backups. In the case of EMMC this function would +//be invoked only once on /dev/block/mmcblk1 since it holds the GPT image +//containing all the partitions For UFS devices it could potentially be +//invoked multiple times, once for each LUN containing critical image(s) and +//their backups +int prepare_partitions(enum boot_update_stage stage, const char *dev_path) +{ + int r = 0; + int fd = -1; + int is_ufs = gpt_utils_is_ufs_device(); + enum gpt_state gpt_prim, gpt_second; + enum boot_update_stage internal_stage; + struct stat xbl_partition_stat; + + if (!dev_path) { + fprintf(stderr, "%s: Invalid dev_path\n", + __func__); + r = -1; + goto EXIT; + } + fd = open(dev_path, O_RDWR); + if (fd < 0) { + fprintf(stderr, "%s: Opening '%s' failed: %s\n", + __func__, + BLK_DEV_FILE, + strerror(errno)); + r = -1; + goto EXIT; + } + r = gpt_get_state(fd, PRIMARY_GPT, &gpt_prim) || + gpt_get_state(fd, SECONDARY_GPT, &gpt_second); + if (r) { + fprintf(stderr, "%s: Getting GPT headers state failed\n", + __func__); + goto EXIT; + } + + /* These 2 combinations are unexpected and unacceptable */ + if (gpt_prim == GPT_BAD_CRC || gpt_second == GPT_BAD_CRC) { + fprintf(stderr, "%s: GPT headers CRC corruption detected, aborting\n", + __func__); + r = -1; + goto EXIT; + } + if (gpt_prim == GPT_BAD_SIGNATURE && gpt_second == GPT_BAD_SIGNATURE) { + fprintf(stderr, "%s: Both GPT headers corrupted, aborting\n", + __func__); + r = -1; + goto EXIT; + } + + /* Check internal update stage according GPT headers' state */ + if (gpt_prim == GPT_OK && gpt_second == GPT_OK) + internal_stage = UPDATE_MAIN; + else if (gpt_prim == GPT_BAD_SIGNATURE) + internal_stage = UPDATE_BACKUP; + else if (gpt_second == GPT_BAD_SIGNATURE) + internal_stage = UPDATE_FINALIZE; + else { + fprintf(stderr, "%s: Abnormal GPTs state: primary (%d), secondary (%d), " + "aborting\n", __func__, gpt_prim, gpt_second); + r = -1; + goto EXIT; + } + + /* Stage already set - ready for update, exitting */ + if ((int) stage == (int) internal_stage - 1) + goto EXIT; + /* Unexpected stage given */ + if (stage != internal_stage) { + r = -1; + goto EXIT; + } + + switch (stage) { + case UPDATE_MAIN: + if (is_ufs) { + if(stat(XBL_PRIMARY, &xbl_partition_stat)|| + stat(XBL_BACKUP, &xbl_partition_stat)){ + //Non fatal error. Just means this target does not + //use XBL but relies on sbl whose update is handled + //by the normal methods. + fprintf(stderr, "%s: xbl part not found(%s).Assuming sbl in use\n", + __func__, + strerror(errno)); + } else { + //Switch the boot lun so that backup boot LUN is used + r = gpt_utils_set_xbl_boot_partition(BACKUP_BOOT); + if(r){ + fprintf(stderr, "%s: Failed to set xbl backup partition as boot\n", + __func__); + goto EXIT; + } + } + } + //Fix up the backup GPT table so that it actually points to + //the backup copy of the boot critical images + fprintf(stderr, "%s: Preparing for primary partition update\n", + __func__); + r = gpt2_set_boot_chain(fd, BACKUP_BOOT); + if (r) { + if (r < 0) + fprintf(stderr, + "%s: Setting secondary GPT to backup boot failed\n", + __func__); + /* No backup partitions - do not corrupt GPT, do not flag error */ + else + r = 0; + goto EXIT; + } + //corrupt the primary GPT so that the backup(which now points to + //the backup boot partitions is used) + r = gpt_set_state(fd, PRIMARY_GPT, GPT_BAD_SIGNATURE); + if (r) { + fprintf(stderr, "%s: Corrupting primary GPT header failed\n", + __func__); + goto EXIT; + } + break; + case UPDATE_BACKUP: + if (is_ufs) { + if(stat(XBL_PRIMARY, &xbl_partition_stat)|| + stat(XBL_BACKUP, &xbl_partition_stat)){ + //Non fatal error. Just means this target does not + //use XBL but relies on sbl whose update is handled + //by the normal methods. + fprintf(stderr, "%s: xbl part not found(%s).Assuming sbl in use\n", + __func__, + strerror(errno)); + } else { + //Switch the boot lun so that backup boot LUN is used + r = gpt_utils_set_xbl_boot_partition(NORMAL_BOOT); + if(r) { + fprintf(stderr, "%s: Failed to set xbl backup partition as boot\n", + __func__); + goto EXIT; + } + } + } + //Fix the primary GPT header so that is used + fprintf(stderr, "%s: Preparing for backup partition update\n", + __func__); + r = gpt_set_state(fd, PRIMARY_GPT, GPT_OK); + if (r) { + fprintf(stderr, "%s: Fixing primary GPT header failed\n", + __func__); + goto EXIT; + } + //Corrupt the scondary GPT header + r = gpt_set_state(fd, SECONDARY_GPT, GPT_BAD_SIGNATURE); + if (r) { + fprintf(stderr, "%s: Corrupting secondary GPT header failed\n", + __func__); + goto EXIT; + } + break; + case UPDATE_FINALIZE: + //Undo the changes we had made in the UPDATE_MAIN stage so that the + //primary/backup GPT headers once again point to the same set of + //partitions + fprintf(stderr, "%s: Finalizing partitions\n", + __func__); + r = gpt2_set_boot_chain(fd, NORMAL_BOOT); + if (r < 0) { + fprintf(stderr, "%s: Setting secondary GPT to normal boot failed\n", + __func__); + goto EXIT; + } + + r = gpt_set_state(fd, SECONDARY_GPT, GPT_OK); + if (r) { + fprintf(stderr, "%s: Fixing secondary GPT header failed\n", + __func__); + goto EXIT; + } + break; + default:; + } + +EXIT: + if (fd >= 0) { + fsync(fd); + close(fd); + } + return r; +} + +int add_lun_to_update_list(char *lun_path, struct update_data *dat) +{ + uint32_t i = 0; + struct stat st; + if (!lun_path || !dat){ + fprintf(stderr, "%s: Invalid data", + __func__); + return -1; + } + if (stat(lun_path, &st)) { + fprintf(stderr, "%s: Unable to access %s. Skipping adding to list", + __func__, + lun_path); + return -1; + } + if (dat->num_valid_entries == 0) { + fprintf(stderr, "%s: Copying %s into lun_list[%d]\n", + __func__, + lun_path, + i); + strlcpy(dat->lun_list[0], lun_path, + PATH_MAX * sizeof(char)); + dat->num_valid_entries = 1; + } else { + for (i = 0; (i < dat->num_valid_entries) && + (dat->num_valid_entries < MAX_LUNS - 1); i++) { + //Check if the current LUN is not already part + //of the lun list + if (!strncmp(lun_path,dat->lun_list[i], + strlen(dat->lun_list[i]))) { + //LUN already in list..Return + return 0; + } + } + fprintf(stderr, "%s: Copying %s into lun_list[%d]\n", + __func__, + lun_path, + dat->num_valid_entries); + //Add LUN path lun list + strlcpy(dat->lun_list[dat->num_valid_entries], lun_path, + PATH_MAX * sizeof(char)); + dat->num_valid_entries++; + } + return 0; +} + +int prepare_boot_update(enum boot_update_stage stage) +{ + int is_ufs = gpt_utils_is_ufs_device(); + struct stat ufs_dir_stat; + struct update_data data; + int rcode = 0; + uint32_t i = 0; + int is_error = 0; + const char ptn_swap_list[][MAX_GPT_NAME_SIZE] = { PTN_SWAP_LIST }; + //Holds /dev/block/bootdevice/by-name/*bak entry + char buf[PATH_MAX] = {0}; + //Holds the resolved path of the symlink stored in buf + char real_path[PATH_MAX] = {0}; + + if (!is_ufs) { + //emmc device. Just pass in path to mmcblk0 + return prepare_partitions(stage, BLK_DEV_FILE); + } else { + //Now we need to find the list of LUNs over + //which the boot critical images are spread + //and set them up for failsafe updates.To do + //this we find out where the symlinks for the + //each of the paths under + ///dev/block/bootdevice/by-name/PTN_SWAP_LIST + //actually point to. + fprintf(stderr, "%s: Running on a UFS device\n", + __func__); + memset(&data, '\0', sizeof(struct update_data)); + for (i=0; i < ARRAY_SIZE(ptn_swap_list); i++) { + //XBL on UFS does not follow the convention + //of being loaded based on well known GUID'S. + //We take care of switching the UFS boot LUN + //explicitly later on. + if (!strncmp(ptn_swap_list[i], + PTN_XBL, + strlen(PTN_XBL))) + continue; + snprintf(buf, sizeof(buf), + "%s/%sbak", + BOOT_DEV_DIR, + ptn_swap_list[i]); + if (stat(buf, &ufs_dir_stat)) { + continue; + } + if (readlink(buf, real_path, sizeof(real_path) - 1) < 0) + { + fprintf(stderr, "%s: readlink error. Skipping %s", + __func__, + strerror(errno)); + } else { + if(strlen(real_path) < PATH_TRUNCATE_LOC + 1){ + fprintf(stderr, "Unknown path.Skipping :%s:\n", + real_path); + } else { + real_path[PATH_TRUNCATE_LOC] = '\0'; + add_lun_to_update_list(real_path, &data); + } + } + memset(buf, '\0', sizeof(buf)); + memset(real_path, '\0', sizeof(real_path)); + } + for (i=0; i < data.num_valid_entries; i++) { + fprintf(stderr, "%s: Preparing %s for update stage %d\n", + __func__, + data.lun_list[i], + stage); + rcode = prepare_partitions(stage, data.lun_list[i]); + if (rcode != 0) + { + fprintf(stderr, "%s: Failed to prepare %s.Continuing..\n", + __func__, + data.lun_list[i]); + is_error = 1; + } + } + } + if (is_error) + return -1; + return 0; +} + +//Given a parttion name(eg: rpm) get the path to the block device that +//represents the GPT disk the partition resides on. In the case of emmc it +//would be the default emmc dev(/dev/block/mmcblk0). In the case of UFS we look +//through the /dev/block/bootdevice/by-name/ tree for partname, and resolve +//the path to the LUN from there. +static int get_dev_path_from_partition_name(const char *partname, + char *buf, + size_t buflen) +{ + struct stat st; + char path[PATH_MAX] = {0}; + if (!partname || !buf || buflen < ((PATH_TRUNCATE_LOC) + 1)) { + ALOGE("%s: Invalid argument", __func__); + goto error; + } + if (gpt_utils_is_ufs_device()) { + //Need to find the lun that holds partition partname + snprintf(path, sizeof(path), + "%s/%s", + BOOT_DEV_DIR, + partname); + if (stat(path, &st)) { + goto error; + } + if (readlink(path, buf, buflen) < 0) + { + goto error; + } else { + buf[PATH_TRUNCATE_LOC] = '\0'; + } + } else { + snprintf(buf, buflen, BLK_DEV_FILE); + } + return 0; + +error: + return -1; +} + +int gpt_utils_get_partition_map(vector<string>& ptn_list, + map<string, vector<string>>& partition_map) { + char devpath[PATH_MAX] = {'\0'}; + map<string, vector<string>>::iterator it; + if (ptn_list.size() < 1) { + fprintf(stderr, "%s: Invalid ptn list\n", __func__); + goto error; + } + //Go through the passed in list + for (uint32_t i = 0; i < ptn_list.size(); i++) + { + //Key in the map is the path to the device that holds the + //partition + if (get_dev_path_from_partition_name(ptn_list[i].c_str(), + devpath, + sizeof(devpath))) { + //Not necessarily an error. The partition may just + //not be present. + continue; + } + string path = devpath; + it = partition_map.find(path); + if (it != partition_map.end()) { + it->second.push_back(ptn_list[i]); + } else { + vector<string> str_vec; + str_vec.push_back( ptn_list[i]); + partition_map.insert(pair<string, vector<string>> + (path, str_vec)); + } + memset(devpath, '\0', sizeof(devpath)); + } + return 0; +error: + return -1; +} + +//Get the block size of the disk represented by decsriptor fd +static uint32_t gpt_get_block_size(int fd) +{ + uint32_t block_size = 0; + if (fd < 0) { + ALOGE("%s: invalid descriptor", + __func__); + goto error; + } + if (ioctl(fd, BLKSSZGET, &block_size) != 0) { + ALOGE("%s: Failed to get GPT dev block size : %s", + __func__, + strerror(errno)); + goto error; + } + return block_size; +error: + return 0; +} + +//Write the GPT header present in the passed in buffer back to the +//disk represented by fd +static int gpt_set_header(uint8_t *gpt_header, int fd, + enum gpt_instance instance) +{ + uint32_t block_size = 0; + off64_t gpt_header_offset = 0; + if (!gpt_header || fd < 0) { + ALOGE("%s: Invalid arguments", + __func__); + goto error; + } + block_size = gpt_get_block_size(fd); + if (block_size == 0) { + ALOGE("%s: Failed to get block size", __func__); + goto error; + } + if (instance == PRIMARY_GPT) + gpt_header_offset = block_size; + else + gpt_header_offset = lseek64(fd, 0, SEEK_END) - block_size; + if (gpt_header_offset <= 0) { + ALOGE("%s: Failed to get gpt header offset",__func__); + goto error; + } + if (blk_rw(fd, 1, gpt_header_offset, gpt_header, block_size)) { + ALOGE("%s: Failed to write back GPT header", __func__); + goto error; + } + return 0; +error: + return -1; +} + +//Read out the GPT header for the disk that contains the partition partname +static uint8_t* gpt_get_header(const char *partname, enum gpt_instance instance) +{ + uint8_t* hdr = NULL; + char devpath[PATH_MAX] = {0}; + int64_t hdr_offset = 0; + uint32_t block_size = 0; + int fd = -1; + if (!partname) { + ALOGE("%s: Invalid partition name", __func__); + goto error; + } + if (get_dev_path_from_partition_name(partname, devpath, sizeof(devpath)) + != 0) { + ALOGE("%s: Failed to resolve path for %s", + __func__, + partname); + goto error; + } + fd = open(devpath, O_RDWR); + if (fd < 0) { + ALOGE("%s: Failed to open %s : %s", + __func__, + devpath, + strerror(errno)); + goto error; + } + block_size = gpt_get_block_size(fd); + if (block_size == 0) + { + ALOGE("%s: Failed to get gpt block size for %s", + __func__, + partname); + goto error; + } + + hdr = (uint8_t*)malloc(block_size); + if (!hdr) { + ALOGE("%s: Failed to allocate memory for gpt header", + __func__); + } + if (instance == PRIMARY_GPT) + hdr_offset = block_size; + else { + hdr_offset = lseek64(fd, 0, SEEK_END) - block_size; + } + if (hdr_offset < 0) { + ALOGE("%s: Failed to get gpt header offset", + __func__); + goto error; + } + if (blk_rw(fd, 0, hdr_offset, hdr, block_size)) { + ALOGE("%s: Failed to read GPT header from device", + __func__); + goto error; + } + close(fd); + return hdr; +error: + if (fd >= 0) + close(fd); + if (hdr) + free(hdr); + return NULL; +} + +//Returns the partition entry array based on the +//passed in buffer which contains the gpt header. +//The fd here is the descriptor for the 'disk' which +//holds the partition +static uint8_t* gpt_get_pentry_arr(uint8_t *hdr, int fd) +{ + uint64_t pentries_start = 0; + uint32_t pentry_size = 0; + uint32_t block_size = 0; + uint32_t pentries_arr_size = 0; + uint8_t *pentry_arr = NULL; + int rc = 0; + if (!hdr) { + ALOGE("%s: Invalid header", __func__); + goto error; + } + if (fd < 0) { + ALOGE("%s: Invalid fd", __func__); + goto error; + } + block_size = gpt_get_block_size(fd); + if (!block_size) { + ALOGE("%s: Failed to get gpt block size for", + __func__); + goto error; + } + pentries_start = GET_8_BYTES(hdr + PENTRIES_OFFSET) * block_size; + pentry_size = GET_4_BYTES(hdr + PENTRY_SIZE_OFFSET); + pentries_arr_size = + GET_4_BYTES(hdr + PARTITION_COUNT_OFFSET) * pentry_size; + pentry_arr = (uint8_t*)calloc(1, pentries_arr_size); + if (!pentry_arr) { + ALOGE("%s: Failed to allocate memory for partition array", + __func__); + goto error; + } + rc = blk_rw(fd, 0, + pentries_start, + pentry_arr, + pentries_arr_size); + if (rc) { + ALOGE("%s: Failed to read partition entry array", + __func__); + goto error; + } + return pentry_arr; +error: + if (pentry_arr) + free(pentry_arr); + return NULL; +} + +static int gpt_set_pentry_arr(uint8_t *hdr, int fd, uint8_t* arr) +{ + uint32_t block_size = 0; + uint64_t pentries_start = 0; + uint32_t pentry_size = 0; + uint32_t pentries_arr_size = 0; + int rc = 0; + if (!hdr || fd < 0 || !arr) { + ALOGE("%s: Invalid argument", __func__); + goto error; + } + block_size = gpt_get_block_size(fd); + if (!block_size) { + ALOGE("%s: Failed to get gpt block size for", + __func__); + goto error; + } + pentries_start = GET_8_BYTES(hdr + PENTRIES_OFFSET) * block_size; + pentry_size = GET_4_BYTES(hdr + PENTRY_SIZE_OFFSET); + pentries_arr_size = + GET_4_BYTES(hdr + PARTITION_COUNT_OFFSET) * pentry_size; + rc = blk_rw(fd, 1, + pentries_start, + arr, + pentries_arr_size); + if (rc) { + ALOGE("%s: Failed to read partition entry array", + __func__); + goto error; + } + return 0; +error: + return -1; +} + + + +//Allocate a handle used by calls to the "gpt_disk" api's +struct gpt_disk * gpt_disk_alloc() +{ + struct gpt_disk *disk; + disk = (struct gpt_disk *)malloc(sizeof(struct gpt_disk)); + if (!disk) { + ALOGE("%s: Failed to allocate memory", __func__); + goto end; + } + memset(disk, 0, sizeof(struct gpt_disk)); +end: + return disk; +} + +//Free previously allocated/initialized handle +void gpt_disk_free(struct gpt_disk *disk) +{ + if (!disk) + return; + if (disk->hdr) + free(disk->hdr); + if (disk->hdr_bak) + free(disk->hdr_bak); + if (disk->pentry_arr) + free(disk->pentry_arr); + if (disk->pentry_arr_bak) + free(disk->pentry_arr_bak); + free(disk); + return; +} + +//fills up the passed in gpt_disk struct with information about the +//disk represented by path dev. Returns 0 on success and -1 on error. +int gpt_disk_get_disk_info(const char *dev, struct gpt_disk *dsk) +{ + + struct gpt_disk *disk = NULL; + int fd = -1; + uint32_t gpt_header_size = 0; + uint32_t crc_zero; + + crc_zero = crc32(0L, Z_NULL, 0); + if (!dsk || !dev) { + ALOGE("%s: Invalid arguments", __func__); + goto error; + } + disk = dsk; + disk->hdr = gpt_get_header(dev, PRIMARY_GPT); + if (!disk->hdr) { + ALOGE("%s: Failed to get primary header", __func__); + goto error; + } + gpt_header_size = GET_4_BYTES(disk->hdr + HEADER_SIZE_OFFSET); + disk->hdr_crc = crc32(crc_zero, disk->hdr, gpt_header_size); + disk->hdr_bak = gpt_get_header(dev, SECONDARY_GPT); + if (!disk->hdr_bak) { + ALOGE("%s: Failed to get backup header", __func__); + goto error; + } + disk->hdr_bak_crc = crc32(crc_zero, disk->hdr_bak, gpt_header_size); + + //Descriptor for the block device. We will use this for further + //modifications to the partition table + if (get_dev_path_from_partition_name(dev, + disk->devpath, + sizeof(disk->devpath)) != 0) { + ALOGE("%s: Failed to resolve path for %s", + __func__, + dev); + goto error; + } + fd = open(disk->devpath, O_RDWR); + if (fd < 0) { + ALOGE("%s: Failed to open %s: %s", + __func__, + disk->devpath, + strerror(errno)); + goto error; + } + disk->pentry_arr = gpt_get_pentry_arr(disk->hdr, fd); + if (!disk->pentry_arr) { + ALOGE("%s: Failed to obtain partition entry array", + __func__); + goto error; + } + disk->pentry_arr_bak = gpt_get_pentry_arr(disk->hdr_bak, fd); + if (!disk->pentry_arr_bak) { + ALOGE("%s: Failed to obtain backup partition entry array", + __func__); + goto error; + } + disk->pentry_size = GET_4_BYTES(disk->hdr + PENTRY_SIZE_OFFSET); + disk->pentry_arr_size = + GET_4_BYTES(disk->hdr + PARTITION_COUNT_OFFSET) * + disk->pentry_size; + disk->pentry_arr_crc = GET_4_BYTES(disk->hdr + PARTITION_CRC_OFFSET); + disk->pentry_arr_bak_crc = GET_4_BYTES(disk->hdr_bak + + PARTITION_CRC_OFFSET); + disk->block_size = gpt_get_block_size(fd); + close(fd); + disk->is_initialized = GPT_DISK_INIT_MAGIC; + return 0; +error: + if (fd >= 0) + close(fd); + return -1; +} + +//Get pointer to partition entry from a allocated gpt_disk structure +uint8_t* gpt_disk_get_pentry(struct gpt_disk *disk, + const char *partname, + enum gpt_instance instance) +{ + uint8_t *ptn_arr = NULL; + if (!disk || !partname || disk->is_initialized != GPT_DISK_INIT_MAGIC) { + ALOGE("%s: Invalid argument",__func__); + goto error; + } + ptn_arr = (instance == PRIMARY_GPT) ? + disk->pentry_arr : disk->pentry_arr_bak; + return (gpt_pentry_seek(partname, ptn_arr, + ptn_arr + disk->pentry_arr_size , + disk->pentry_size)); +error: + return NULL; +} + +//Update CRC values for the various components of the gpt_disk +//structure. This function should be called after any of the fields +//have been updated before the structure contents are written back to +//disk. +int gpt_disk_update_crc(struct gpt_disk *disk) +{ + uint32_t gpt_header_size = 0; + uint32_t crc_zero; + crc_zero = crc32(0L, Z_NULL, 0); + if (!disk || (disk->is_initialized != GPT_DISK_INIT_MAGIC)) { + ALOGE("%s: invalid argument", __func__); + goto error; + } + //Recalculate the CRC of the primary partiton array + disk->pentry_arr_crc = crc32(crc_zero, + disk->pentry_arr, + disk->pentry_arr_size); + //Recalculate the CRC of the backup partition array + disk->pentry_arr_bak_crc = crc32(crc_zero, + disk->pentry_arr_bak, + disk->pentry_arr_size); + //Update the partition CRC value in the primary GPT header + PUT_4_BYTES(disk->hdr + PARTITION_CRC_OFFSET, disk->pentry_arr_crc); + //Update the partition CRC value in the backup GPT header + PUT_4_BYTES(disk->hdr_bak + PARTITION_CRC_OFFSET, + disk->pentry_arr_bak_crc); + //Update the CRC value of the primary header + gpt_header_size = GET_4_BYTES(disk->hdr + HEADER_SIZE_OFFSET); + //Header CRC is calculated with its own CRC field set to 0 + PUT_4_BYTES(disk->hdr + HEADER_CRC_OFFSET, 0); + PUT_4_BYTES(disk->hdr_bak + HEADER_CRC_OFFSET, 0); + disk->hdr_crc = crc32(crc_zero, disk->hdr, gpt_header_size); + disk->hdr_bak_crc = crc32(crc_zero, disk->hdr_bak, gpt_header_size); + PUT_4_BYTES(disk->hdr + HEADER_CRC_OFFSET, disk->hdr_crc); + PUT_4_BYTES(disk->hdr_bak + HEADER_CRC_OFFSET, disk->hdr_bak_crc); + return 0; +error: + return -1; +} + +//Write the contents of struct gpt_disk back to the actual disk +int gpt_disk_commit(struct gpt_disk *disk) +{ + int fd = -1; + if (!disk || (disk->is_initialized != GPT_DISK_INIT_MAGIC)){ + ALOGE("%s: Invalid args", __func__); + goto error; + } + fd = open(disk->devpath, O_RDWR); + if (fd < 0) { + ALOGE("%s: Failed to open %s: %s", + __func__, + disk->devpath, + strerror(errno)); + goto error; + } + //Write the primary header + if(gpt_set_header(disk->hdr, fd, PRIMARY_GPT) != 0) { + ALOGE("%s: Failed to update primary GPT header", + __func__); + goto error; + } + //Write back the primary partition array + if (gpt_set_pentry_arr(disk->hdr, fd, disk->pentry_arr)) { + ALOGE("%s: Failed to write primary GPT partition arr", + __func__); + goto error; + } + //Write back the secondary header + if(gpt_set_header(disk->hdr_bak, fd, SECONDARY_GPT) != 0) { + ALOGE("%s: Failed to update secondary GPT header", + __func__); + goto error; + } + //Write back the secondary partition array + if (gpt_set_pentry_arr(disk->hdr_bak, fd, disk->pentry_arr_bak)) { + ALOGE("%s: Failed to write secondary GPT partition arr", + __func__); + goto error; + } + close(fd); + return 0; +error: + if (fd >= 0) + close(fd); + return -1; +} |