From 87d308708712ff6075c4dd54b0519b47fdad8816 Mon Sep 17 00:00:00 2001 From: Oleksandr Suvorov Date: Thu, 26 Mar 2020 12:44:27 +0200 Subject: Backports v5.4.27 Backports generated by toradex backports f6e8852f1ef28e6d3c9bae8400eb6a87a6b0c3e7 against mainline kernel tag v5.4.27 Signed-off-by: Oleksandr Suvorov --- compat/lib-crypto-arc4.c | 74 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 74 insertions(+) create mode 100644 compat/lib-crypto-arc4.c (limited to 'compat/lib-crypto-arc4.c') diff --git a/compat/lib-crypto-arc4.c b/compat/lib-crypto-arc4.c new file mode 100644 index 0000000..c2020f1 --- /dev/null +++ b/compat/lib-crypto-arc4.c @@ -0,0 +1,74 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Cryptographic API + * + * ARC4 Cipher Algorithm + * + * Jon Oberheide + */ + +#include +#include + +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_LICENSE("GPL"); -- cgit v1.2.3