From 8df9996699cdf96887613f99181173295a19bd76 Mon Sep 17 00:00:00 2001 From: Cyrille Bagard Date: Tue, 23 Mar 2021 08:57:58 +0100 Subject: Create methods to deal with hex conversions. --- plugins/pychrysalide/common/Makefile.am | 1 + plugins/pychrysalide/common/hex.c | 186 ++++++++++++++++++++++++++++++++ plugins/pychrysalide/common/hex.h | 39 +++++++ plugins/pychrysalide/common/module.c | 2 + src/common/Makefile.am | 1 + src/common/hex.c | 139 ++++++++++++++++++++++++ src/common/hex.h | 42 ++++++++ tests/common/hex.py | 28 +++++ 8 files changed, 438 insertions(+) create mode 100644 plugins/pychrysalide/common/hex.c create mode 100644 plugins/pychrysalide/common/hex.h create mode 100644 src/common/hex.c create mode 100644 src/common/hex.h create mode 100644 tests/common/hex.py diff --git a/plugins/pychrysalide/common/Makefile.am b/plugins/pychrysalide/common/Makefile.am index 5f54fe8..1fb268d 100644 --- a/plugins/pychrysalide/common/Makefile.am +++ b/plugins/pychrysalide/common/Makefile.am @@ -4,6 +4,7 @@ noinst_LTLIBRARIES = libpychrysacommon.la libpychrysacommon_la_SOURCES = \ bits.h bits.c \ fnv1a.h fnv1a.c \ + hex.h hex.c \ leb128.h leb128.c \ module.h module.c \ packed.h packed.c \ diff --git a/plugins/pychrysalide/common/hex.c b/plugins/pychrysalide/common/hex.c new file mode 100644 index 0000000..6f84c19 --- /dev/null +++ b/plugins/pychrysalide/common/hex.c @@ -0,0 +1,186 @@ + +/* Chrysalide - Outil d'analyse de fichiers binaires + * hex.c - équivalent Python du fichier "common/hex.c" + * + * 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 this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + + +#include "hex.h" + + +#include +#include +#include + + +#include + + +#include "../access.h" +#include "../helpers.h" + + + +/* Encode des données en chaîne hexadécimale. */ +static PyObject *py_hex_encode_hex(PyObject *, PyObject *); + +/* Décode un caractère hexadécimal. */ +static PyObject *py_hex_decode_hex_digit(PyObject *, PyObject *); + + + +/****************************************************************************** +* * +* Paramètres : self = objet Python concerné par l'appel. * +* args = arguments à utiliser pour l'opération. * +* * +* Description : Encode des données en chaîne hexadécimale. * +* * +* Retour : Chaîne hexadécimale. * +* * +* Remarques : - * +* * +******************************************************************************/ + +static PyObject *py_hex_encode_hex(PyObject *self, PyObject *args) +{ + PyObject *result; /* Valeur à retourner */ + int lower; /* Taille des caractères finaux*/ + const char *data; /* Données à traiter */ + Py_ssize_t len; /* Quantité de ces données */ + int ret; /* Bilan de lecture des args. */ + char *buffer; /* Tampon de travail */ + +#define HEX_ENCODE_HEX_METHOD PYTHON_METHOD_DEF \ +( \ + encode_hex, "data, /, lower = True", \ + METH_VARARGS, py_hex, \ + "Convert data to a hex string.\n" \ + "\n" \ + "The *data* has to be a string or a read-only bytes-like object." \ + " The *lower* argument defines the case of the result string.\n" \ + "\n" \ + "This method may be only usefull for the internal test suite as" \ + " there is a native Python alternative:\n" \ + "\n" \ + " b'ABC'.hex()\n" \ + " '414243'" \ +) + + lower = 1; + + ret = PyArg_ParseTuple(args, "s#|p", &data, &len, &lower); + if (!ret) return NULL; + + buffer = malloc((len * 2 + 1) * sizeof(char)); + + encode_hex(data, len, lower, buffer); + + result = PyUnicode_FromString(buffer); + + free(buffer); + + return result; + +} + + +/****************************************************************************** +* * +* Paramètres : self = objet Python concerné par l'appel. * +* args = arguments à utiliser pour l'opération. * +* * +* Description : Décode un caractère hexadécimal. * +* * +* Retour : Bilan de l'opération : valeur en cas de succès, None sinon. * +* * +* Remarques : - * +* * +******************************************************************************/ + +static PyObject *py_hex_decode_hex_digit(PyObject *self, PyObject *args) +{ + PyObject *result; /* Valeur à retourner */ + char byte; /* Valeur hexadécimale */ + int ret; /* Bilan de lecture des args. */ + uint8_t value; /* Valeur brute transcrite */ + bool status; /* Bilan de l'opération */ + +#define HEX_DECODE_HEX_DIGIT_METHOD PYTHON_METHOD_DEF \ +( \ + decode_hex_digit, "chr", \ + METH_VARARGS, py_hex, \ + "Convert a string character to an integer value." \ + "\n" \ + "The *chr* can be a string character of length 1.\n" \ + "\n" \ + "The result is an integer value on success or *None*" \ + " in case of failure." \ +) + + ret = PyArg_ParseTuple(args, "C", &byte); + if (!ret) return NULL; + + status = decode_hex_digit((const char *)&byte, &value); + + if (status) + result = PyLong_FromUnsignedLong(value); + + else + { + result = Py_None; + Py_INCREF(result); + } + + return result; + +} + + +/****************************************************************************** +* * +* Paramètres : - * +* * +* Description : Définit une extension du module 'common' à compléter. * +* * +* Retour : Bilan de l'opération. * +* * +* Remarques : - * +* * +******************************************************************************/ + +bool populate_common_module_with_hex(void) +{ + bool result; /* Bilan à retourner */ + PyObject *module; /* Module à recompléter */ + + static PyMethodDef py_hex_methods[] = { + HEX_ENCODE_HEX_METHOD, + HEX_DECODE_HEX_DIGIT_METHOD, + { NULL } + }; + + module = get_access_to_python_module("pychrysalide.common"); + + result = register_python_module_methods(module, py_hex_methods); + + return result; + +} diff --git a/plugins/pychrysalide/common/hex.h b/plugins/pychrysalide/common/hex.h new file mode 100644 index 0000000..6dee397 --- /dev/null +++ b/plugins/pychrysalide/common/hex.h @@ -0,0 +1,39 @@ + +/* Chrysalide - Outil d'analyse de fichiers binaires + * hex.h - prototypes pour l'équivalent Python du fichier "common/hex.h" + * + * 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 this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + + +#ifndef _PLUGINS_PYCHRYSALIDE_COMMON_HEX_H +#define _PLUGINS_PYCHRYSALIDE_COMMON_HEX_H + + +#include +#include + + + +/* Définit une extension du module 'common' à compléter. */ +bool populate_common_module_with_hex(void); + + + +#endif /* _PLUGINS_PYCHRYSALIDE_COMMON_HEX_H */ diff --git a/plugins/pychrysalide/common/module.c b/plugins/pychrysalide/common/module.c index cc50c43..6ced1b7 100644 --- a/plugins/pychrysalide/common/module.c +++ b/plugins/pychrysalide/common/module.c @@ -27,6 +27,7 @@ #include "bits.h" #include "fnv1a.h" +#include "hex.h" #include "leb128.h" #include "packed.h" #include "pathname.h" @@ -97,6 +98,7 @@ bool populate_common_module(void) result = true; if (result) result = populate_common_module_with_fnv1a(); + if (result) result = populate_common_module_with_hex(); if (result) result = populate_common_module_with_leb128(); if (result) result = populate_common_module_with_pathname(); if (result) result = populate_common_module_with_pearson(); 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 . + */ + + +#include "hex.h" + + +#include + + + +/****************************************************************************** +* * +* 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 . + */ + + +#ifndef _COMMON_HEX_H +#define _COMMON_HEX_H + + +#include +#include +#include + + + +/* 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 */ diff --git a/tests/common/hex.py b/tests/common/hex.py new file mode 100644 index 0000000..f76b6a8 --- /dev/null +++ b/tests/common/hex.py @@ -0,0 +1,28 @@ + +from chrysacase import ChrysalideTestCase +from pychrysalide.common import encode_hex, decode_hex_digit + + +class TestHexValues(ChrysalideTestCase): + """TestCase for common hexadecimal features*""" + + def testHexEncoding(self): + """Convert data to hex string.""" + + ref = b'ABC' + + self.assertEqual(encode_hex(ref), ref.hex()) + + ref = 'ABC' + + self.assertEqual(encode_hex(ref), bytes(ref, 'ascii').hex()) + + ref = 'ABC' + + self.assertEqual(encode_hex(ref, False), bytes(ref, 'ascii').hex().upper()) + + + def testHexDecoding(self): + """Convert a hex string to value.""" + + self.assertEqual(decode_hex_digit('A'), 0xa) -- cgit v0.11.2-87-g4458