initial commit

1 files changed, 77 insertions, 0 deletions

diff --git a/code/crypto/chacha/chacha.c b/code/crypto/chacha/chacha.c
new file mode 100644
index 0000000..fba03c9
--- /dev/null
+++ b/code/crypto/chacha/chacha.c
@@ -0,0 +1,77 @@
+/* $OpenBSD: chacha.c,v 1.7 2015/12/09 14:07:55 bcook Exp $ */
+/*
+ * Copyright (c) 2014 Joel Sing <jsing@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <stdint.h>
+
+#include <chacha.h>
+
+#include "chacha-merged.c"
+
+void
+ChaCha_set_key(ChaCha_ctx *ctx, const unsigned char *key, uint32_t keybits)
+{
+	chacha_keysetup((chacha_ctx *)ctx, key, keybits);
+	ctx->unused = 0;
+}
+
+void
+ChaCha_set_iv(ChaCha_ctx *ctx, const unsigned char *iv,
+    const unsigned char *counter)
+{
+	chacha_ivsetup((chacha_ctx *)ctx, iv, counter);
+	ctx->unused = 0;
+}
+
+void
+ChaCha(ChaCha_ctx *ctx, unsigned char *out, const unsigned char *in, size_t len)
+{
+	unsigned char *k;
+	int i, l;
+
+	/* Consume remaining keystream, if any exists. */
+	if (ctx->unused > 0) {
+		k = ctx->ks + 64 - ctx->unused;
+		l = (len > ctx->unused) ? ctx->unused : len;
+		for (i = 0; i < l; i++)
+			*(out++) = *(in++) ^ *(k++);
+		ctx->unused -= l;
+		len -= l;
+	}
+
+	chacha_encrypt_bytes((chacha_ctx *)ctx, in, out, (uint32_t)len);
+}
+
+void
+CRYPTO_chacha_20(unsigned char *out, const unsigned char *in, size_t len,
+    const unsigned char key[32], const unsigned char iv[8], uint64_t counter)
+{
+	struct chacha_ctx ctx;
+
+	/*
+	 * chacha_ivsetup expects the counter to be in u8. Rather than
+	 * converting size_t to u8 and then back again, pass a counter of
+	 * NULL and manually assign it afterwards.
+	 */
+	chacha_keysetup(&ctx, key, 256);
+	chacha_ivsetup(&ctx, iv, NULL);
+	if (counter != 0) {
+		ctx.input[12] = (uint32_t)counter;
+		ctx.input[13] = (uint32_t)(counter >> 32);
+	}
+
+	chacha_encrypt_bytes(&ctx, in, out, (uint32_t)len);
+}