diff options
author | Cyrille Bagard <nocbos@gmail.com> | 2021-03-23 07:57:58 (GMT) |
---|---|---|
committer | Cyrille Bagard <nocbos@gmail.com> | 2021-03-23 07:57:58 (GMT) |
commit | 8df9996699cdf96887613f99181173295a19bd76 (patch) | |
tree | 8015ff855566f9581a00630f591a919d38f7a8ec /src | |
parent | eb470f2e5e790ba107171a3ae8c5ed27a72ed8f8 (diff) |
Create methods to deal with hex conversions.
Diffstat (limited to 'src')
-rw-r--r-- | src/common/Makefile.am | 1 | ||||
-rw-r--r-- | src/common/hex.c | 139 | ||||
-rw-r--r-- | src/common/hex.h | 42 |
3 files changed, 182 insertions, 0 deletions
diff --git a/src/common/Makefile.am b/src/common/Makefile.am index 2162d8c..3379eed 100644 --- a/src/common/Makefile.am +++ b/src/common/Makefile.am @@ -13,6 +13,7 @@ libcommon_la_SOURCES = \ endianness.h endianness.c \ environment.h environment.c \ extstr.h extstr.c \ + hex.h hex.c \ ibuf.h ibuf.c \ io.h io.c \ fnv1a.h fnv1a.c \ diff --git a/src/common/hex.c b/src/common/hex.c new file mode 100644 index 0000000..afa23a8 --- /dev/null +++ b/src/common/hex.c @@ -0,0 +1,139 @@ + +/* Chrysalide - Outil d'analyse de fichiers binaires + * hex.c - construction et interprétation de chaînes hexadécimales + * + * Copyright (C) 2021 Cyrille Bagard + * + * This file is part of Chrysalide. + * + * Chrysalide is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 3 of the License, or + * (at your option) any later version. + * + * Chrysalide is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with Chrysalide. If not, see <http://www.gnu.org/licenses/>. + */ + + +#include "hex.h" + + +#include <ctype.h> + + + +/****************************************************************************** +* * +* Paramètres : src = source de données à considérer. * +* len = quantité de ces données à traiter. * +* lower = spécifie un encodage à l'aide de minuscules. * +* dst = zone allouée pour les données résultantes. [OUT] * +* * +* Description : Encode des données en chaîne hexadécimale. * +* * +* Retour : - * +* * +* Remarques : - * +* * +******************************************************************************/ + +void encode_hex(const char *src, size_t len, bool lower, char *dst) +{ + size_t i; /* Boucle de parcours #1 */ + uint8_t index; /* Indice de recherche */ + + /** + * base = "".join([ "%02X" % i for i in range(256) ]) + * encoded = "\n".join([ base[i : i + 32] for i in range(0, 512, 32) ]) + * print(encoded) + */ + const char encoding_lookup[] = { + "000102030405060708090A0B0C0D0E0F" + "101112131415161718191A1B1C1D1E1F" + "202122232425262728292A2B2C2D2E2F" + "303132333435363738393A3B3C3D3E3F" + "404142434445464748494A4B4C4D4E4F" + "505152535455565758595A5B5C5D5E5F" + "606162636465666768696A6B6C6D6E6F" + "707172737475767778797A7B7C7D7E7F" + "808182838485868788898A8B8C8D8E8F" + "909192939495969798999A9B9C9D9E9F" + "A0A1A2A3A4A5A6A7A8A9AAABACADAEAF" + "B0B1B2B3B4B5B6B7B8B9BABBBCBDBEBF" + "C0C1C2C3C4C5C6C7C8C9CACBCCCDCECF" + "D0D1D2D3D4D5D6D7D8D9DADBDCDDDEDF" + "E0E1E2E3E4E5E6E7E8E9EAEBECEDEEEF" + "F0F1F2F3F4F5F6F7F8F9FAFBFCFDFEFF" + }; + + for (i = 0; i < len; i++) + { + index = src[i]; + + if (lower) + { + (*dst++) = tolower(encoding_lookup[index * 2]); + (*dst++) = tolower(encoding_lookup[index * 2 + 1]); + } + else + { + (*dst++) = encoding_lookup[index * 2]; + (*dst++) = encoding_lookup[index * 2 + 1]; + } + + } + + *dst = '\0'; + +} + + +/****************************************************************************** +* * +* Paramètres : digit = caractère hexadécimale à transcrire. * +* value = valeur récupérée. [OUT] * +* * +* Description : Décode un caractère hexadécimal. * +* * +* Retour : Bilan de l'opération. * +* * +* Remarques : - * +* * +******************************************************************************/ + +bool decode_hex_digit(const char *digit, uint8_t *value) +{ + bool result; /* Validité à retourner */ + + switch (*digit) + { + case '0' ... '9': + *value = (*digit) - '0'; + result = true; + break; + + case 'a' ... 'f': + *value = 0xa + (*digit) - 'a'; + result = true; + break; + + case 'A' ... 'F': + *value = 0xa + (*digit) - 'A'; + result = true; + break; + + default: + result = false; + break; + + } + + return result; + +} diff --git a/src/common/hex.h b/src/common/hex.h new file mode 100644 index 0000000..97cd0da --- /dev/null +++ b/src/common/hex.h @@ -0,0 +1,42 @@ + +/* Chrysalide - Outil d'analyse de fichiers binaires + * hex.h - prototypes pour la construction et l'interprétation de chaînes hexadécimales + * + * Copyright (C) 2021 Cyrille Bagard + * + * This file is part of Chrysalide. + * + * Chrysalide is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 3 of the License, or + * (at your option) any later version. + * + * Chrysalide is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with Chrysalide. If not, see <http://www.gnu.org/licenses/>. + */ + + +#ifndef _COMMON_HEX_H +#define _COMMON_HEX_H + + +#include <stdbool.h> +#include <stddef.h> +#include <stdint.h> + + + +/* Encode des données en chaîne hexadécimale. */ +void encode_hex(const char *, size_t, bool, char *); + +/* Décode un caractère hexadécimal. */ +bool decode_hex_digit(const char *, uint8_t *); + + + +#endif /* _COMMON_HEX_H */ |