| /* |
| * |
| * Copyright (c) 2013-2017 Nest Labs, Inc. |
| * All rights reserved. |
| * |
| * Licensed 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. |
| */ |
| |
| /** |
| * @file |
| * This file implements an object for Verhoeff's check-digit |
| * algorithm for base-32 strings. |
| * |
| */ |
| |
| #include <stdint.h> |
| #include <stdio.h> |
| #include <string.h> |
| #include <ctype.h> |
| |
| #include "Verhoeff.h" |
| |
| #ifndef VERHOEFF32_NO_MULTIPLY_TABLE |
| |
| uint8_t Verhoeff32::sMultiplyTable[] = |
| { |
| 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, |
| 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 0, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 16, |
| 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 0, 1, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 16, 17, |
| 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 0, 1, 2, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 16, 17, 18, |
| 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 0, 1, 2, 3, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 16, 17, 18, 19, |
| 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 0, 1, 2, 3, 4, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 16, 17, 18, 19, 20, |
| 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 0, 1, 2, 3, 4, 5, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 16, 17, 18, 19, 20, 21, |
| 7, 8, 9, 10, 11, 12, 13, 14, 15, 0, 1, 2, 3, 4, 5, 6, 23, 24, 25, 26, 27, 28, 29, 30, 31, 16, 17, 18, 19, 20, 21, 22, |
| 8, 9, 10, 11, 12, 13, 14, 15, 0, 1, 2, 3, 4, 5, 6, 7, 24, 25, 26, 27, 28, 29, 30, 31, 16, 17, 18, 19, 20, 21, 22, 23, |
| 9, 10, 11, 12, 13, 14, 15, 0, 1, 2, 3, 4, 5, 6, 7, 8, 25, 26, 27, 28, 29, 30, 31, 16, 17, 18, 19, 20, 21, 22, 23, 24, |
| 10, 11, 12, 13, 14, 15, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 26, 27, 28, 29, 30, 31, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, |
| 11, 12, 13, 14, 15, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 27, 28, 29, 30, 31, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, |
| 12, 13, 14, 15, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 28, 29, 30, 31, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, |
| 13, 14, 15, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 29, 30, 31, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, |
| 14, 15, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 30, 31, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, |
| 15, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 31, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, |
| 16, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 0, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, |
| 17, 16, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 1, 0, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, |
| 18, 17, 16, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 2, 1, 0, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, |
| 19, 18, 17, 16, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 20, 3, 2, 1, 0, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, |
| 20, 19, 18, 17, 16, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 4, 3, 2, 1, 0, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, |
| 21, 20, 19, 18, 17, 16, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22, 5, 4, 3, 2, 1, 0, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, |
| 22, 21, 20, 19, 18, 17, 16, 31, 30, 29, 28, 27, 26, 25, 24, 23, 6, 5, 4, 3, 2, 1, 0, 15, 14, 13, 12, 11, 10, 9, 8, 7, |
| 23, 22, 21, 20, 19, 18, 17, 16, 31, 30, 29, 28, 27, 26, 25, 24, 7, 6, 5, 4, 3, 2, 1, 0, 15, 14, 13, 12, 11, 10, 9, 8, |
| 24, 23, 22, 21, 20, 19, 18, 17, 16, 31, 30, 29, 28, 27, 26, 25, 8, 7, 6, 5, 4, 3, 2, 1, 0, 15, 14, 13, 12, 11, 10, 9, |
| 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 31, 30, 29, 28, 27, 26, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0, 15, 14, 13, 12, 11, 10, |
| 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 31, 30, 29, 28, 27, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0, 15, 14, 13, 12, 11, |
| 27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 31, 30, 29, 28, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0, 15, 14, 13, 12, |
| 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 31, 30, 29, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0, 15, 14, 13, |
| 29, 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 31, 30, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0, 15, 14, |
| 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 31, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0, 15, |
| 31, 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0, |
| }; |
| |
| #endif // VERHOEFF32_NO_MULTIPLY_TABLE |
| |
| uint8_t Verhoeff32::sPermTable[] = |
| { |
| // Detects all single digit and adjacent transposition errors, and 97.076613% of jump transposition errors. |
| 7, 2, 1, 30, 16, 20, 27, 11, 31, 6, 8, 13, 29, 5, 10, 21, 22, 3, 24, 0, 23, 25, 12, 9, 28, 14, 4, 15, 17, 18, 19, 26, |
| }; |
| |
| int8_t Verhoeff32::sCharToValTable[] = |
| { |
| // NOTE: table starts at ASCII 30h |
| 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, -1, -1, -1, -1, -1, -1, |
| -1, 10, 11, 12, 13, 14, 15, 16, 17, -1, 18, 19, 20, 21, 22, -1, |
| 23, -1, 24, 25, 26, 27, 28, 29, 30, 31, -1, -1, -1, -1, -1, -1, |
| -1, 10, 11, 12, 13, 14, 15, 16, 17, -1, 18, 19, 20, 21, 22, -1, |
| 23, -1, 24, 25, 26, 27, 28, 29, 30, 31 |
| }; |
| |
| char Verhoeff32::sValToCharTable[] = "0123456789ABCDEFGHJKLMNPRSTUVWXY"; |
| |
| char Verhoeff32::ComputeCheckChar(const char *str) |
| { |
| return ComputeCheckChar(str, strlen(str)); |
| } |
| |
| char Verhoeff32::ComputeCheckChar(const char *str, size_t strLen) |
| { |
| int c = 0; |
| |
| for (size_t i = 1; i <= strLen; i++) |
| { |
| char ch = str[strLen - i]; |
| |
| int val = CharToVal(ch); |
| if (val < 0) |
| return 0; // invalid character |
| |
| int p = Verhoeff::Permute(val, sPermTable, Base, i); |
| |
| #ifdef VERHOEFF32_NO_MULTIPLY_TABLE |
| c = Verhoeff::DihedralMultiply(c, p, PolygonSize); |
| #else |
| c = sMultiplyTable[c * Base + p]; |
| #endif |
| } |
| |
| c = Verhoeff::DihedralInvert(c, PolygonSize); |
| |
| return ValToChar(c); |
| } |
| |
| bool Verhoeff32::ValidateCheckChar(char checkChar, const char *str) |
| { |
| return ValidateCheckChar(checkChar, str, strlen(str)); |
| } |
| |
| bool Verhoeff32::ValidateCheckChar(char checkChar, const char *str, size_t strLen) |
| { |
| return (ComputeCheckChar(str, strLen) == checkChar); |
| } |
| |
| bool Verhoeff32::ValidateCheckChar(const char *str) |
| { |
| return ValidateCheckChar(str, strlen(str)); |
| } |
| |
| bool Verhoeff32::ValidateCheckChar(const char *str, size_t strLen) |
| { |
| if (strLen == 0) |
| return false; |
| return ValidateCheckChar(str[strLen - 1], str, strLen - 1); |
| } |
| |
| int Verhoeff32::CharToVal(char ch) |
| { |
| if (ch >= '0' && ch <= 'y') |
| return sCharToValTable[(int)ch - '0']; |
| else |
| return -1; |
| } |
| |
| char Verhoeff32::ValToChar(int val) |
| { |
| if (val >= 0 && val < Base) |
| return sValToCharTable[val]; |
| else |
| return 0; |
| } |
