v4.19.13 snapshot.
diff --git a/crypto/salsa20_generic.c b/crypto/salsa20_generic.c
new file mode 100644
index 0000000..8c77bc7
--- /dev/null
+++ b/crypto/salsa20_generic.c
@@ -0,0 +1,213 @@
+/*
+ * 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:
+ * http://www.ecrypt.eu.org/stream/
+ * http://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)];
+
+ if (dst != src)
+ memcpy(dst, src, bytes);
+
+ while (bytes >= SALSA20_BLOCK_SIZE) {
+ salsa20_block(state, stream);
+ crypto_xor(dst, (const u8 *)stream, SALSA20_BLOCK_SIZE);
+ bytes -= SALSA20_BLOCK_SIZE;
+ dst += SALSA20_BLOCK_SIZE;
+ }
+ if (bytes) {
+ salsa20_block(state, stream);
+ crypto_xor(dst, (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, true);
+
+ salsa20_init(state, ctx, walk.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);
+}
+
+module_init(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");