// SPDX-License-Identifier: GPL-2.0-or-later/* * Cryptographic API * * ARC4 Cipher Algorithm * * Jon Oberheide <jon@oberheide.org> */ #include <crypto/arc4.h>#include <linux/export.h>#include <linux/module.h> int arc4_setkey(struct arc4_ctx *ctx, const u8 *in_key, unsigned int key_len){ int i, j = 0, k = 0; ctx->x = 1; ctx->y = 0; for (i = 0; i < 256; i++) ctx->S[i] = i; for (i = 0; i < 256; i++) { u32 a = ctx->S[i]; j = (j + in_key[k] + a) & 0xff; ctx->S[i] = ctx->S[j]; ctx->S[j] = a; if (++k >= key_len) k = 0; } return 0;}EXPORT_SYMBOL(arc4_setkey); void arc4_crypt(struct arc4_ctx *ctx, u8 *out, const u8 *in, unsigned int len){ u32 *const S = ctx->S; u32 x, y, a, b; u32 ty, ta, tb; if (len == 0) return; x = ctx->x; y = ctx->y; a = S[x]; y = (y + a) & 0xff; b = S[y]; do { S[y] = a; a = (a + b) & 0xff; S[x] = b; x = (x + 1) & 0xff; ta = S[x]; ty = (y + ta) & 0xff; tb = S[ty]; *out++ = *in++ ^ S[a]; if (--len == 0) break; y = ty; a = ta; b = tb; } while (true); ctx->x = x; ctx->y = y;}EXPORT_SYMBOL(arc4_crypt); MODULE_DESCRIPTION("ARC4 Cipher Algorithm");MODULE_LICENSE("GPL");
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Cryptographic API
*
* ARC4 Cipher Algorithm
*
* Jon Oberheide <jon@oberheide.org>
*/
#include <crypto/arc4.h>
#include <linux/export.h>
#include <linux/module.h>
int arc4_setkey(struct arc4_ctx *ctx, const u8 *in_key, unsigned int key_len)
{
int i, j = 0, k = 0;
ctx->x = 1;
ctx->y = 0;
for (i = 0; i < 256; i++)
ctx->S[i] = i;
for (i = 0; i < 256; i++) {
u32 a = ctx->S[i];
j = (j + in_key[k] + a) & 0xff;
ctx->S[i] = ctx->S[j];
ctx->S[j] = a;
if (++k >= key_len)
k = 0;
}
return 0;
}
EXPORT_SYMBOL(arc4_setkey);
void arc4_crypt(struct arc4_ctx *ctx, u8 *out, const u8 *in, unsigned int len)
{
u32 *const S = ctx->S;
u32 x, y, a, b;
u32 ty, ta, tb;
if (len == 0)
return;
x = ctx->x;
y = ctx->y;
a = S[x];
y = (y + a) & 0xff;
b = S[y];
do {
S[y] = a;
a = (a + b) & 0xff;
S[x] = b;
x = (x + 1) & 0xff;
ta = S[x];
ty = (y + ta) & 0xff;
tb = S[ty];
*out++ = *in++ ^ S[a];
if (--len == 0)
break;
y = ty;
a = ta;
b = tb;
} while (true);
ctx->x = x;
ctx->y = y;
}
EXPORT_SYMBOL(arc4_crypt);
MODULE_DESCRIPTION("ARC4 Cipher Algorithm");
MODULE_LICENSE("GPL");