| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| |
| #include <nffs/nffs.h> |
| #include <nffs/os.h> |
| |
| int |
| nffs_crc_flash(uint16_t initial_crc, uint8_t area_idx, uint32_t area_offset, |
| uint32_t len, uint16_t *out_crc) |
| { |
| uint32_t chunk_len; |
| uint16_t crc; |
| int rc; |
| |
| crc = initial_crc; |
| |
| /* Copy data in chunks small enough to fit in the flash buffer. */ |
| while (len > 0) { |
| if (len > sizeof nffs_flash_buf) { |
| chunk_len = sizeof nffs_flash_buf; |
| } else { |
| chunk_len = len; |
| } |
| |
| STATS_INC(nffs_stats, nffs_readcnt_crc); |
| rc = nffs_flash_read(area_idx, area_offset, nffs_flash_buf, chunk_len); |
| if (rc != 0) { |
| return rc; |
| } |
| |
| crc = nffs_os_crc16_ccitt(crc, nffs_flash_buf, chunk_len, 0); |
| |
| area_offset += chunk_len; |
| len -= chunk_len; |
| } |
| |
| *out_crc = crc; |
| return 0; |
| } |
| |
| uint16_t |
| nffs_crc_disk_block_hdr(const struct nffs_disk_block *disk_block) |
| { |
| uint16_t crc; |
| |
| crc = nffs_os_crc16_ccitt(0, disk_block, NFFS_DISK_BLOCK_OFFSET_CRC, 0); |
| |
| return crc; |
| } |
| |
| static int |
| nffs_crc_disk_block(const struct nffs_disk_block *disk_block, |
| uint8_t area_idx, uint32_t area_offset, |
| uint16_t *out_crc) |
| { |
| uint16_t crc; |
| int rc; |
| |
| crc = nffs_crc_disk_block_hdr(disk_block); |
| |
| rc = nffs_crc_flash(crc, area_idx, area_offset + sizeof *disk_block, |
| disk_block->ndb_data_len, &crc); |
| if (rc != 0) { |
| return rc; |
| } |
| |
| /* Finish CRC */ |
| crc = nffs_os_crc16_ccitt(crc, NULL, 0, 1); |
| |
| *out_crc = crc; |
| return 0; |
| } |
| |
| int |
| nffs_crc_disk_block_validate(const struct nffs_disk_block *disk_block, |
| uint8_t area_idx, uint32_t area_offset) |
| { |
| uint16_t crc; |
| int rc; |
| |
| rc = nffs_crc_disk_block(disk_block, area_idx, area_offset, &crc); |
| if (rc != 0) { |
| return rc; |
| } |
| |
| if (crc != disk_block->ndb_crc16) { |
| return FS_ECORRUPT; |
| } |
| |
| return 0; |
| } |
| |
| void |
| nffs_crc_disk_block_fill(struct nffs_disk_block *disk_block, const void *data) |
| { |
| uint16_t crc16; |
| |
| crc16 = nffs_crc_disk_block_hdr(disk_block); |
| crc16 = nffs_os_crc16_ccitt(crc16, data, disk_block->ndb_data_len, 1); |
| |
| disk_block->ndb_crc16 = crc16; |
| } |
| |
| static uint16_t |
| nffs_crc_disk_inode_hdr(const struct nffs_disk_inode *disk_inode) |
| { |
| uint16_t crc; |
| |
| crc = nffs_os_crc16_ccitt(0, disk_inode, NFFS_DISK_INODE_OFFSET_CRC, 1); |
| |
| return crc; |
| } |
| |
| static int |
| nffs_crc_disk_inode(const struct nffs_disk_inode *disk_inode, |
| uint8_t area_idx, uint32_t area_offset, |
| uint16_t *out_crc) |
| { |
| uint16_t crc; |
| int rc; |
| |
| crc = nffs_crc_disk_inode_hdr(disk_inode); |
| |
| rc = nffs_crc_flash(crc, area_idx, area_offset + sizeof *disk_inode, |
| disk_inode->ndi_filename_len, &crc); |
| if (rc != 0) { |
| return rc; |
| } |
| |
| /* Finish CRC */ |
| crc = nffs_os_crc16_ccitt(crc, NULL, 0, 1); |
| |
| *out_crc = crc; |
| return 0; |
| } |
| |
| int |
| nffs_crc_disk_inode_validate(const struct nffs_disk_inode *disk_inode, |
| uint8_t area_idx, uint32_t area_offset) |
| { |
| uint16_t crc; |
| int rc; |
| |
| rc = nffs_crc_disk_inode(disk_inode, area_idx, area_offset, &crc); |
| if (rc != 0) { |
| return rc; |
| } |
| |
| if (crc != disk_inode->ndi_crc16) { |
| return FS_ECORRUPT; |
| } |
| |
| return 0; |
| } |
| |
| void |
| nffs_crc_disk_inode_fill(struct nffs_disk_inode *disk_inode, |
| const char *filename) |
| { |
| uint16_t crc16; |
| |
| crc16 = nffs_crc_disk_inode_hdr(disk_inode); |
| crc16 = nffs_os_crc16_ccitt(crc16, filename, |
| disk_inode->ndi_filename_len, 1); |
| |
| disk_inode->ndi_crc16 = crc16; |
| } |