crypto_rol.c

Go to the documentation of this file.

// SPDX-FileCopyrightText: 2016 pancake <pancake@nopcode.org>
// SPDX-License-Identifier: LGPL-3.0-only
 
#include <rz_lib.h>
#include <rz_crypto.h>
#include <rz_util.h>
 
#define NAME "rol"
 
enum { MAX_rol_KEY_SIZE = 32768 };
 
struct rol_state {
    ut8 key[MAX_rol_KEY_SIZE];
    int key_size;
};
 
static bool rol_init_state(struct rol_state *const state, const ut8 *key, int keylen) {
    if (!state || !key || keylen < 1 || keylen > MAX_rol_KEY_SIZE) {
        return false;
    }
    int i;
    state->key_size = keylen;
    for (i = 0; i < keylen; i++) {
        state->key[i] = key[i];
    }
    return true;
}
 
static void rol_crypt(struct rol_state *const state, const ut8 *inbuf, ut8 *outbuf, int buflen) {
    int i;
    for (i = 0; i < buflen; i++) {
        ut8 count = state->key[i % state->key_size] & 7;
        ut8 inByte = inbuf[i];
        outbuf[i] = (inByte << count) | (inByte >> ((8 - count) & 7));
    }
}
 
static bool rol_set_key(RzCrypto *cry, const ut8 *key, int keylen, int mode, int direction) {
    rz_return_val_if_fail(cry->user && key, false);
    struct rol_state *st = (struct rol_state *)cry->user;
 
    cry->dir = direction;
    return rol_init_state(st, key, keylen);
}
 
static int rol_get_key_size(RzCrypto *cry) {
    rz_return_val_if_fail(cry->user, 0);
    struct rol_state *st = (struct rol_state *)cry->user;
 
    return st->key_size;
}
 
static bool rol_use(const char *algo) {
    return !strcmp(algo, NAME);
}
 
static bool update(RzCrypto *cry, const ut8 *buf, int len) {
    rz_return_val_if_fail(cry->user, false);
    struct rol_state *st = (struct rol_state *)cry->user;
 
    if (cry->dir) {
        eprintf("Use ROR algorithm to decrypt\n");
        return false;
    }
    ut8 *obuf = calloc(1, len);
    if (!obuf) {
        return false;
    }
    rol_crypt(st, buf, obuf, len);
    rz_crypto_append(cry, obuf, len);
    free(obuf);
    return true;
}
 
static bool rol_init(RzCrypto *cry) {
    rz_return_val_if_fail(cry, false);
 
    cry->user = RZ_NEW0(struct rol_state);
    return cry->user != NULL;
}
 
static bool rol_fini(RzCrypto *cry) {
    rz_return_val_if_fail(cry, false);
 
    free(cry->user);
    return true;
}
 
RzCryptoPlugin rz_crypto_plugin_rol = {
    .name = NAME,
    .author = "pancake",
    .license = "LGPL-3",
    .set_key = rol_set_key,
    .get_key_size = rol_get_key_size,
    .use = rol_use,
    .update = update,
    .final = update,
    .init = rol_init,
    .fini = rol_fini,
};
 
#ifndef RZ_PLUGIN_INCORE
RZ_API RzLibStruct rizin_plugin = {
    .type = RZ_LIB_TYPE_CRYPTO,
    .data = &rz_crypto_plugin_rol,
    .version = RZ_VERSION
};
#endif