1 files changed, 23 insertions, 0 deletions
diff --git a/libblake_blake2xb_digest.c b/libblake_blake2xb_digest.c
new file mode 100644
index 0000000..b9a65ec
--- /dev/null
+++ b/libblake_blake2xb_digest.c
@@ -0,0 +1,23 @@
+/* See LICENSE file for copyright and license details. */
+#include "common.h"
+
+void
+libblake_blake2xb_digest(const struct libblake_blake2xb_state *state,
+                         uint_least32_t i /* start 0, increase by 1 until i * 64 >= desired hash length */,
+                         uint_least8_t len /* desired hash MIN(length - i * 64, 64) */,
+                         unsigned char output[static len] /* output for hash offset by i * 64 */)
+{
+	struct libblake_blake2xb_state xstate;
+	struct libblake_blake2xb_params xparams;
+
+	xparams = state->xof_params;
+	xparams.node_offset = i;
+	xparams.digest_len = len;
+
+	libblake_internal_blake2xb_init0(&xstate, &xparams);
+
+	xstate.b2b.f[0] = UINT_LEAST64_C(0xFFFFffffFFFFffff);
+	xstate.b2b.t[0] = (uint_least64_t)state->xof_params.digest_len & UINT_LEAST64_C(0xFFFFffffFFFFffff);
+	libblake_internal_blake2b_compress(&xstate.b2b, state->intermediate);
+	libblake_internal_blake2b_output_digest(&xstate.b2b, (size_t)len, output);
+}