/* radare - LGPL - Copyright 2024-2026 - pancake */

#include <r_lib.h>
#include <r_muta.h>
#include <r_hash.h>
#include <r_endian.h>

typedef struct {
	const char *name;
	enum CRC_PRESETS preset;
	int digest_size;
} CrcAlgorithm;

static const CrcAlgorithm crc_algorithms[] = {
	{ "crc8smbus", CRC_PRESET_8_SMBUS, 1 },
	{ "crc15can", CRC_PRESET_15_CAN, 2 },
	{ "crc16", CRC_PRESET_16, 2 },
	{ "crc16hdlc", CRC_PRESET_16_HDLC, 2 },
	{ "crc16usb", CRC_PRESET_16_USB, 2 },
	{ "crc16citt", CRC_PRESET_16_CITT, 2 },
	{ "crc24", CRC_PRESET_24, 3 },
	{ "crc32", CRC_PRESET_32, 4 },
	{ "crc32c", CRC_PRESET_32C, 4 },
	{ "crc32ecma267", CRC_PRESET_32_ECMA_267, 4 },
	{ "crc32bzip2", CRC_PRESET_CRC32_BZIP2, 4 },
	{ "crc32d", CRC_PRESET_CRC32D, 4 },
	{ "crc32mpeg2", CRC_PRESET_CRC32_MPEG2, 4 },
	{ "crc32posix", CRC_PRESET_CRC32_POSIX, 4 },
	{ "crc32q", CRC_PRESET_CRC32Q, 4 },
	{ "crc32jamcrc", CRC_PRESET_CRC32_JAMCRC, 4 },
	{ "crc32xfer", CRC_PRESET_CRC32_XFER, 4 },
	{ "crc64", CRC_PRESET_CRC64, 8 },
	{ "crc64ecma", CRC_PRESET_CRC64_ECMA182, 8 },
	{ "crc64we", CRC_PRESET_CRC64_WE, 8 },
	{ "crc64xz", CRC_PRESET_CRC64_XZ, 8 },
	{ "crc64iso", CRC_PRESET_CRC64_ISO, 8 },
};

static const CrcAlgorithm *crc_find(const char *algo) {
	const size_t amount = sizeof (crc_algorithms) / sizeof (crc_algorithms[0]);
	size_t i;
	for (i = 0; i < amount; i++) {
		if (!strcmp (algo, crc_algorithms[i].name)) {
			return &crc_algorithms[i];
		}
	}
	return NULL;
}

static bool crc_check(const char *algo) {
	return crc_find (algo) != NULL;
}

static bool crc_update(RMutaSession *ms, const ut8 *buf, int len) {
	const CrcAlgorithm *algo = ms->subtype? crc_find (ms->subtype): NULL;
	if (!algo) {
		return false;
	}
	utcrc result = r_hash_crc_preset (buf, len, algo->preset);
	ut8 digest[8] = { 0 };
	switch (algo->digest_size) {
	case 1: digest[0] = (ut8)result; break;
	case 2: r_write_be16 (digest, (ut16)result); break;
	case 3: r_write_be24 (digest, (ut32)result); break;
	case 4: r_write_be32 (digest, (ut32)result); break;
	case 8: r_write_be64 (digest, (ut64)result); break;
	default: return false; /* Invalid digest size */
	}
	r_muta_session_append (ms, digest, algo->digest_size);
	return true;
}

RMutaPlugin r_muta_plugin_crc = {
	.meta = {
		.name = "crc",
		.desc = "CRC8/CRC15/CRC16/CRC24/CRC32/CRC64 hash algorithms",
		.author = "pancake",
		.license = "MIT",
	},
	.type = R_MUTA_TYPE_HASH,
	.implements = "crc8smbus,crc15can,crc16,crc16hdlc,crc16usb,crc16citt,crc24,crc32,crc32c,crc32ecma267,crc32bzip2,crc32d,crc32mpeg2,crc32posix,crc32q,crc32jamcrc,crc32xfer,crc64,crc64ecma,crc64we,crc64xz,crc64iso",
	.check = crc_check,
	.update = crc_update,
	.end = crc_update
};

#ifndef R2_PLUGIN_INCORE
R_API RLibStruct radare_plugin = {
	.type = R_LIB_TYPE_CRYPTO,
	.data = &r_muta_plugin_crc,
	.version = R2_VERSION
};
#endif