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-rw-r--r--plugins/encodings/base64.c139
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diff --git a/plugins/encodings/base64.c b/plugins/encodings/base64.c
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+
+/* Chrysalide - Outil d'analyse de fichiers binaires
+ * base64.c - calculs d'encodages en base 64
+ *
+ * Copyright (C) 2020 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 "base64.h"
+
+
+
+/******************************************************************************
+* *
+* Paramètres : input = données d'entrée à traiter. *
+* output = données sortantes constituées. [OUT] *
+* alphabet = alphabet d'encodage mis à disposition. *
+* *
+* Description : Procède à l'encodage d'un contenu en base 64. *
+* *
+* Retour : Bilan de l'opération : true en cas de réussite, false sinon. *
+* *
+* Remarques : - *
+* *
+******************************************************************************/
+
+bool _base64_encode(const sized_binary_t *input, sized_string_t *output, const sized_string_t *alphabet)
+{
+ bool result; /* Bilan à retourner */
+ const bin_t *src; /* Tête de lecture #1 */
+ const bin_t *alpha; /* Tête de lecture #2 */
+ bin_t *iter; /* Tête d'écriture */
+ size_t i; /* Boucle de parcours */
+
+ result = (alphabet->len == 64);
+ if (!result) goto exit;
+
+ /* Création du réceptacle */
+
+ output->len = input->len * 4 / 3;
+
+ if (output->len % 4 != 0)
+ output->len += (4 - output->len % 4);
+
+ output->data = malloc((output->len + 1) * sizeof(bin_t));
+
+ /* Encodage du corps du message */
+
+ src = input->static_bin_data;
+ alpha = alphabet->static_bin_data;
+
+ iter = output->bin_data;
+
+ if (input->len > 2)
+ for (i = 0; i < (input->len - 2); i += 3)
+ {
+ *iter++ = alpha[(src[i] >> 2) & 0x3f];
+
+ *iter++ = alpha[((src[i] & 0x03) << 4) | ((src[i + 1] & 0xf0) >> 4)];
+
+ *iter++ = alpha[((src[i + 1] & 0x0f) << 2) | ((src[i + 2] & 0xc0) >> 6)];
+
+ *iter++ = alpha[src[i + 2] & 0x3f];
+
+ }
+ else
+ i = 0;
+
+ /* Bourrage final ? */
+
+ if (i < input->len)
+ {
+ *iter++ = alpha[(src[i] >> 2) & 0x3f];
+
+ if (i == (input->len - 1))
+ {
+ *iter++ = alpha[((src[i] & 0x03) << 4)];
+ *iter++ = '=';
+ }
+ else
+ {
+ *iter++ = alpha[((src[i] & 0x03) << 4) | ((src[i + 1] & 0xf0) >> 4)];
+ *iter++ = alpha[((src[i + 1] & 0x0f) << 2)];
+ }
+
+ *iter++ = '=';
+ }
+
+ *iter = 0x00;
+
+ exit:
+
+ return result;
+
+}
+
+
+/******************************************************************************
+* *
+* Paramètres : input = données d'entrée à traiter. *
+* output = données sortantes constituées. [OUT] *
+* *
+* Description : Procède à l'encodage par défaut d'un contenu en base 64. *
+* *
+* Retour : Bilan de l'opération : true en cas de réussite, false sinon. *
+* *
+* Remarques : - *
+* *
+******************************************************************************/
+
+bool base64_encode(const sized_binary_t *input, sized_string_t *output)
+{
+ bool result; /* Bilan à retourner */
+
+ const sized_string_t alphabet = {
+ .static_data = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/",
+ .len = 64
+ };
+
+ result = _base64_encode(input, output, &alphabet);
+
+ return result;
+
+}