1 files changed, 56 insertions, 0 deletions
diff --git a/lib/blake2/blake2s.h b/lib/blake2/blake2s.h
new file mode 100644
index 0000000..64b4156
--- /dev/null
+++ b/lib/blake2/blake2s.h
@@ -0,0 +1,56 @@
+#pragma once
+
+#include <stddef.h>
+#include <stdint.h>
+
+struct BLAKE2s_param {
+  uint8_t outlen; // digest length
+  uint8_t keylen; // key length
+  uint8_t fanout;
+  uint8_t depth;
+  uint32_t leaf_length;
+  uint32_t node_offset;
+  uint16_t node_offset_ex;
+  uint8_t node_depth;
+  uint8_t inner_length;
+  uint64_t salt;
+  uint64_t personalization;
+};
+
+struct BLAKE2s_ctx {
+  uint8_t b[64]; // input buffer
+  size_t c;      // pointer for b[]
+  uint32_t h[8]; // chained state vector h
+  uint32_t t[2]; // total number of bytes
+  struct BLAKE2s_param param; // parameter block
+};
+
+/**
+ * 3.1 Mixing Function G
+ */
+void G(uint32_t V[16], unsigned a, unsigned b, unsigned c, unsigned d, uint32_t x, uint32_t y);
+
+/**
+ * 3.2 Compression Function F
+ * @param t: 2w-bit offset counter t
+ * @param f: final block indicator flag f
+ */
+void F(struct BLAKE2s_ctx *context, uint32_t m[16], uint32_t f);
+
+int BLAKE2s_init(struct BLAKE2s_ctx *ctx, uint8_t outlen, const void *key, uint8_t keylen);
+void BLAKE2s_update(struct BLAKE2s_ctx *ctx, const void *d, size_t dd);
+void BLAKE2s_final(struct BLAKE2s_ctx *ctx, void *out);
+
+// All-in-one convenience function.
+static inline int
+BLAKE2s(void *out, uint8_t outlen,       // return buffer for digest
+        const void *key, uint8_t keylen, // optional secret key
+        const void *in, size_t inlen)    // data to be hashed
+{
+  struct BLAKE2s_ctx ctx;
+  if (BLAKE2s_init(&ctx, outlen, key, keylen)) return -1;
+  BLAKE2s_update(&ctx, in, inlen);
+  BLAKE2s_final(&ctx, out);
+
+  return 0;
+}