| /* |
| * 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 <cutils/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; |
| } |