1 files changed, 38 insertions, 0 deletions

diff --git a/src/lib/libcrypto/chacha/chacha.c b/src/lib/libcrypto/chacha/chacha.c
new file mode 100644
index 0000000000..d76d64de4a
--- /dev/null
+++ b/src/lib/libcrypto/chacha/chacha.c
@@ -0,0 +1,38 @@
+/*
+ * 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 "chacha-merged.c"
+
+void
+CRYPTO_chacha_20(unsigned char *out, const unsigned char *in, size_t len,
+    const unsigned char key[32], const unsigned char iv[8], size_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)(((uint64_t)counter) >> 32);
+        }
+
+        chacha_encrypt_bytes(&ctx, in, out, (uint32_t)len);
+}