| /* |
| * 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 <crc/crc8.h> |
| |
| #include "fcb/fcb.h" |
| #include "fcb_priv.h" |
| |
| /* |
| * Given offset in flash area, fill in rest of the fcb_entry, and crc8 over |
| * the data. |
| */ |
| int |
| fcb_elem_crc8(struct fcb *fcb, struct fcb_entry *loc, uint8_t *c8p) |
| { |
| uint8_t tmp_str[FCB_TMP_BUF_SZ]; |
| int cnt; |
| int blk_sz; |
| uint8_t crc8; |
| uint16_t len; |
| uint32_t off; |
| uint32_t end; |
| int rc; |
| |
| if (loc->fe_elem_off + 2 > loc->fe_area->fa_size) { |
| return FCB_ERR_NOVAR; |
| } |
| rc = flash_area_read_is_empty(loc->fe_area, loc->fe_elem_off, tmp_str, 2); |
| if (rc < 0) { |
| return FCB_ERR_FLASH; |
| } else if (rc == 1) { |
| return FCB_ERR_NOVAR; |
| } |
| |
| cnt = fcb_get_len(tmp_str, &len); |
| loc->fe_data_off = loc->fe_elem_off + fcb_len_in_flash(fcb, cnt); |
| loc->fe_data_len = len; |
| |
| crc8 = crc8_init(); |
| crc8 = crc8_calc(crc8, tmp_str, cnt); |
| |
| off = loc->fe_data_off; |
| end = loc->fe_data_off + len; |
| for (; off < end; off += blk_sz) { |
| blk_sz = end - off; |
| if (blk_sz > sizeof(tmp_str)) { |
| blk_sz = sizeof(tmp_str); |
| } |
| |
| rc = flash_area_read(loc->fe_area, off, tmp_str, blk_sz); |
| if (rc) { |
| return FCB_ERR_FLASH; |
| } |
| crc8 = crc8_calc(crc8, tmp_str, blk_sz); |
| } |
| *c8p = crc8; |
| |
| return 0; |
| } |
| |
| int |
| fcb_elem_info(struct fcb *fcb, struct fcb_entry *loc) |
| { |
| int rc; |
| uint8_t crc8; |
| uint8_t fl_crc8; |
| uint32_t off; |
| |
| rc = fcb_elem_crc8(fcb, loc, &crc8); |
| if (rc) { |
| return rc; |
| } |
| off = loc->fe_data_off + fcb_len_in_flash(fcb, loc->fe_data_len); |
| |
| rc = flash_area_read(loc->fe_area, off, &fl_crc8, sizeof(fl_crc8)); |
| if (rc) { |
| return FCB_ERR_FLASH; |
| } |
| |
| if (fl_crc8 != crc8) { |
| return FCB_ERR_CRC; |
| } |
| return 0; |
| } |