Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 212 insertions, 0 deletions

diff --git a/crypto/salsa20_generic.c b/crypto/salsa20_generic.c
new file mode 100644
index 000000000..3418869da
--- /dev/null
+++ b/crypto/salsa20_generic.c
@@ -0,0 +1,212 @@
+/*
+ * Salsa20: Salsa20 stream cipher algorithm
+ *
+ * Copyright (c) 2007 Tan Swee Heng <thesweeheng@gmail.com>
+ *
+ * Derived from:
+ * - salsa20.c: Public domain C code by Daniel J. Bernstein <djb@cr.yp.to>
+ *
+ * Salsa20 is a stream cipher candidate in eSTREAM, the ECRYPT Stream
+ * Cipher Project. It is designed by Daniel J. Bernstein <djb@cr.yp.to>.
+ * More information about eSTREAM and Salsa20 can be found here:
+ *   https://www.ecrypt.eu.org/stream/
+ *   https://cr.yp.to/snuffle.html
+ *
+ * This program 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 2 of the License, or (at your option)
+ * any later version.
+ *
+ */
+
+#include <asm/unaligned.h>
+#include <crypto/internal/skcipher.h>
+#include <linux/module.h>
+
+#define SALSA20_IV_SIZE        8
+#define SALSA20_MIN_KEY_SIZE  16
+#define SALSA20_MAX_KEY_SIZE  32
+#define SALSA20_BLOCK_SIZE    64
+
+struct salsa20_ctx {
+	u32 initial_state[16];
+};
+
+static void salsa20_block(u32 *state, __le32 *stream)
+{
+	u32 x[16];
+	int i;
+
+	memcpy(x, state, sizeof(x));
+
+	for (i = 0; i < 20; i += 2) {
+		x[ 4] ^= rol32((x[ 0] + x[12]),  7);
+		x[ 8] ^= rol32((x[ 4] + x[ 0]),  9);
+		x[12] ^= rol32((x[ 8] + x[ 4]), 13);
+		x[ 0] ^= rol32((x[12] + x[ 8]), 18);
+		x[ 9] ^= rol32((x[ 5] + x[ 1]),  7);
+		x[13] ^= rol32((x[ 9] + x[ 5]),  9);
+		x[ 1] ^= rol32((x[13] + x[ 9]), 13);
+		x[ 5] ^= rol32((x[ 1] + x[13]), 18);
+		x[14] ^= rol32((x[10] + x[ 6]),  7);
+		x[ 2] ^= rol32((x[14] + x[10]),  9);
+		x[ 6] ^= rol32((x[ 2] + x[14]), 13);
+		x[10] ^= rol32((x[ 6] + x[ 2]), 18);
+		x[ 3] ^= rol32((x[15] + x[11]),  7);
+		x[ 7] ^= rol32((x[ 3] + x[15]),  9);
+		x[11] ^= rol32((x[ 7] + x[ 3]), 13);
+		x[15] ^= rol32((x[11] + x[ 7]), 18);
+		x[ 1] ^= rol32((x[ 0] + x[ 3]),  7);
+		x[ 2] ^= rol32((x[ 1] + x[ 0]),  9);
+		x[ 3] ^= rol32((x[ 2] + x[ 1]), 13);
+		x[ 0] ^= rol32((x[ 3] + x[ 2]), 18);
+		x[ 6] ^= rol32((x[ 5] + x[ 4]),  7);
+		x[ 7] ^= rol32((x[ 6] + x[ 5]),  9);
+		x[ 4] ^= rol32((x[ 7] + x[ 6]), 13);
+		x[ 5] ^= rol32((x[ 4] + x[ 7]), 18);
+		x[11] ^= rol32((x[10] + x[ 9]),  7);
+		x[ 8] ^= rol32((x[11] + x[10]),  9);
+		x[ 9] ^= rol32((x[ 8] + x[11]), 13);
+		x[10] ^= rol32((x[ 9] + x[ 8]), 18);
+		x[12] ^= rol32((x[15] + x[14]),  7);
+		x[13] ^= rol32((x[12] + x[15]),  9);
+		x[14] ^= rol32((x[13] + x[12]), 13);
+		x[15] ^= rol32((x[14] + x[13]), 18);
+	}
+
+	for (i = 0; i < 16; i++)
+		stream[i] = cpu_to_le32(x[i] + state[i]);
+
+	if (++state[8] == 0)
+		state[9]++;
+}
+
+static void salsa20_docrypt(u32 *state, u8 *dst, const u8 *src,
+			    unsigned int bytes)
+{
+	__le32 stream[SALSA20_BLOCK_SIZE / sizeof(__le32)];
+
+	while (bytes >= SALSA20_BLOCK_SIZE) {
+		salsa20_block(state, stream);
+		crypto_xor_cpy(dst, src, (const u8 *)stream,
+			       SALSA20_BLOCK_SIZE);
+		bytes -= SALSA20_BLOCK_SIZE;
+		dst += SALSA20_BLOCK_SIZE;
+		src += SALSA20_BLOCK_SIZE;
+	}
+	if (bytes) {
+		salsa20_block(state, stream);
+		crypto_xor_cpy(dst, src, (const u8 *)stream, bytes);
+	}
+}
+
+static void salsa20_init(u32 *state, const struct salsa20_ctx *ctx,
+			 const u8 *iv)
+{
+	memcpy(state, ctx->initial_state, sizeof(ctx->initial_state));
+	state[6] = get_unaligned_le32(iv + 0);
+	state[7] = get_unaligned_le32(iv + 4);
+}
+
+static int salsa20_setkey(struct crypto_skcipher *tfm, const u8 *key,
+			  unsigned int keysize)
+{
+	static const char sigma[16] = "expand 32-byte k";
+	static const char tau[16] = "expand 16-byte k";
+	struct salsa20_ctx *ctx = crypto_skcipher_ctx(tfm);
+	const char *constants;
+
+	if (keysize != SALSA20_MIN_KEY_SIZE &&
+	    keysize != SALSA20_MAX_KEY_SIZE)
+		return -EINVAL;
+
+	ctx->initial_state[1] = get_unaligned_le32(key + 0);
+	ctx->initial_state[2] = get_unaligned_le32(key + 4);
+	ctx->initial_state[3] = get_unaligned_le32(key + 8);
+	ctx->initial_state[4] = get_unaligned_le32(key + 12);
+	if (keysize == 32) { /* recommended */
+		key += 16;
+		constants = sigma;
+	} else { /* keysize == 16 */
+		constants = tau;
+	}
+	ctx->initial_state[11] = get_unaligned_le32(key + 0);
+	ctx->initial_state[12] = get_unaligned_le32(key + 4);
+	ctx->initial_state[13] = get_unaligned_le32(key + 8);
+	ctx->initial_state[14] = get_unaligned_le32(key + 12);
+	ctx->initial_state[0]  = get_unaligned_le32(constants + 0);
+	ctx->initial_state[5]  = get_unaligned_le32(constants + 4);
+	ctx->initial_state[10] = get_unaligned_le32(constants + 8);
+	ctx->initial_state[15] = get_unaligned_le32(constants + 12);
+
+	/* space for the nonce; it will be overridden for each request */
+	ctx->initial_state[6] = 0;
+	ctx->initial_state[7] = 0;
+
+	/* initial block number */
+	ctx->initial_state[8] = 0;
+	ctx->initial_state[9] = 0;
+
+	return 0;
+}
+
+static int salsa20_crypt(struct skcipher_request *req)
+{
+	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+	const struct salsa20_ctx *ctx = crypto_skcipher_ctx(tfm);
+	struct skcipher_walk walk;
+	u32 state[16];
+	int err;
+
+	err = skcipher_walk_virt(&walk, req, false);
+
+	salsa20_init(state, ctx, req->iv);
+
+	while (walk.nbytes > 0) {
+		unsigned int nbytes = walk.nbytes;
+
+		if (nbytes < walk.total)
+			nbytes = round_down(nbytes, walk.stride);
+
+		salsa20_docrypt(state, walk.dst.virt.addr, walk.src.virt.addr,
+				nbytes);
+		err = skcipher_walk_done(&walk, walk.nbytes - nbytes);
+	}
+
+	return err;
+}
+
+static struct skcipher_alg alg = {
+	.base.cra_name		= "salsa20",
+	.base.cra_driver_name	= "salsa20-generic",
+	.base.cra_priority	= 100,
+	.base.cra_blocksize	= 1,
+	.base.cra_ctxsize	= sizeof(struct salsa20_ctx),
+	.base.cra_module	= THIS_MODULE,
+
+	.min_keysize		= SALSA20_MIN_KEY_SIZE,
+	.max_keysize		= SALSA20_MAX_KEY_SIZE,
+	.ivsize			= SALSA20_IV_SIZE,
+	.chunksize		= SALSA20_BLOCK_SIZE,
+	.setkey			= salsa20_setkey,
+	.encrypt		= salsa20_crypt,
+	.decrypt		= salsa20_crypt,
+};
+
+static int __init salsa20_generic_mod_init(void)
+{
+	return crypto_register_skcipher(&alg);
+}
+
+static void __exit salsa20_generic_mod_fini(void)
+{
+	crypto_unregister_skcipher(&alg);
+}
+
+subsys_initcall(salsa20_generic_mod_init);
+module_exit(salsa20_generic_mod_fini);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION ("Salsa20 stream cipher algorithm");
+MODULE_ALIAS_CRYPTO("salsa20");
+MODULE_ALIAS_CRYPTO("salsa20-generic");