diff --git a/hash/hash_blake2b.c b/hash/hash_blake2b.c
index 69b254ed..3c7b7578 100644
--- a/hash/hash_blake2b.c
+++ b/hash/hash_blake2b.c
@@ -28,53 +28,45 @@
 #endif
 
 /**
- * @define bb
  * @brief the size of a data block in bytes
  */
 #define bb 128
 
 /**
- * @define KK_MAX
  * @brief max key length for BLAKE2b
  */
 #define KK_MAX 64
 
 /**
- * @define NN_MAX
  * @brief max length of BLAKE2b digest in bytes
  */
 #define NN_MAX 64
 
 /**
- * @define CEIL
  * @brief ceiling division macro without floats
  *
  * @param a dividend
- * @param divisor
+ * @param b divisor
  */
 #define CEIL(a, b) (((a) / (b)) + ((a) % (b) != 0))
 
 /**
- * @define MIN
  * @brief returns minimum value
  */
 #define MIN(a, b) ((a) < (b) ? (a) : (b))
 
 /**
- * @define MAX
  * @brief returns maximum value
  */
 #define MAX(a, b) ((a) > (b) ? (a) : (b))
 
 /**
- * @define ROTR64
  * @brief macro to rotate 64-bit ints to the right
  * Ripped from RFC 7693
  */
 #define ROTR64(n, offset) (((n) >> (offset)) ^ ((n) << (64 - (offset))))
 
 /**
- * @define U128_ZERO
  * @brief zero-value initializer for u128 type
  */
 #define U128_ZERO \
@@ -344,7 +336,8 @@ static int BLAKE2B(uint8_t *dest, block_t *d, size_t dd, u128 ll, uint8_t kk,
     return 0;
 }
 
-/* @brief blake2b hash function
+/**
+ * @brief blake2b hash function
  *
  * This is the front-end function that sets up the argument for BLAKE2B().
  *
@@ -398,7 +391,7 @@ uint8_t *blake2b(const uint8_t *message, size_t len, const uint8_t *key,
     /* If there is a secret key it occupies the first block */
     for (i = 0; i < kk; i++)
     {
-        long_hold = message[i];
+        long_hold = key[i];
         long_hold <<= 8 * (i % 8);
 
         word_in_block = (i % bb) / 8;
@@ -449,15 +442,14 @@ static void assert_bytes(const uint8_t *expected, const uint8_t *actual,
     {
         assert(expected[i] == actual[i]);
     }
-
-    printf("All tests have successfully passed!\n");
 }
 
 /**
- * @brief Main function
- * @returns 0 on exit
+ * @brief testing function
+ *
+ * @returns void
  */
-int main()
+static void test()
 {
     uint8_t *digest = NULL;
 
@@ -476,5 +468,84 @@ int main()
 
     free(digest);
 
+    uint8_t key[64] = {
+        0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a,
+        0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15,
+        0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x20,
+        0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b,
+        0x2c, 0x2d, 0x2e, 0x2f, 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36,
+        0x37, 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f};
+    uint8_t key_answer[64] = {
+        0x10, 0xeb, 0xb6, 0x77, 0x00, 0xb1, 0x86, 0x8e, 0xfb, 0x44, 0x17,
+        0x98, 0x7a, 0xcf, 0x46, 0x90, 0xae, 0x9d, 0x97, 0x2f, 0xb7, 0xa5,
+        0x90, 0xc2, 0xf0, 0x28, 0x71, 0x79, 0x9a, 0xaa, 0x47, 0x86, 0xb5,
+        0xe9, 0x96, 0xe8, 0xf0, 0xf4, 0xeb, 0x98, 0x1f, 0xc2, 0x14, 0xb0,
+        0x05, 0xf4, 0x2d, 0x2f, 0xf4, 0x23, 0x34, 0x99, 0x39, 0x16, 0x53,
+        0xdf, 0x7a, 0xef, 0xcb, 0xc1, 0x3f, 0xc5, 0x15, 0x68};
+
+    digest = blake2b(NULL, 0, key, 64, 64);
+    assert_bytes(key_answer, digest, 64);
+
+    free(digest);
+
+    uint8_t zero[1] = {0};
+    uint8_t zero_key[64] = {
+        0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a,
+        0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15,
+        0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x20,
+        0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b,
+        0x2c, 0x2d, 0x2e, 0x2f, 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36,
+        0x37, 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f};
+    uint8_t zero_answer[64] = {
+        0x96, 0x1f, 0x6d, 0xd1, 0xe4, 0xdd, 0x30, 0xf6, 0x39, 0x01, 0x69,
+        0x0c, 0x51, 0x2e, 0x78, 0xe4, 0xb4, 0x5e, 0x47, 0x42, 0xed, 0x19,
+        0x7c, 0x3c, 0x5e, 0x45, 0xc5, 0x49, 0xfd, 0x25, 0xf2, 0xe4, 0x18,
+        0x7b, 0x0b, 0xc9, 0xfe, 0x30, 0x49, 0x2b, 0x16, 0xb0, 0xd0, 0xbc,
+        0x4e, 0xf9, 0xb0, 0xf3, 0x4c, 0x70, 0x03, 0xfa, 0xc0, 0x9a, 0x5e,
+        0xf1, 0x53, 0x2e, 0x69, 0x43, 0x02, 0x34, 0xce, 0xbd};
+
+    digest = blake2b(zero, 1, zero_key, 64, 64);
+    assert_bytes(zero_answer, digest, 64);
+
+    free(digest);
+
+    uint8_t filled[64] = {
+        0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a,
+        0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15,
+        0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x20,
+        0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b,
+        0x2c, 0x2d, 0x2e, 0x2f, 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36,
+        0x37, 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f};
+    uint8_t filled_key[64] = {
+        0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a,
+        0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15,
+        0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x20,
+        0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b,
+        0x2c, 0x2d, 0x2e, 0x2f, 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36,
+        0x37, 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f};
+    uint8_t filled_answer[64] = {
+        0x65, 0x67, 0x6d, 0x80, 0x06, 0x17, 0x97, 0x2f, 0xbd, 0x87, 0xe4,
+        0xb9, 0x51, 0x4e, 0x1c, 0x67, 0x40, 0x2b, 0x7a, 0x33, 0x10, 0x96,
+        0xd3, 0xbf, 0xac, 0x22, 0xf1, 0xab, 0xb9, 0x53, 0x74, 0xab, 0xc9,
+        0x42, 0xf1, 0x6e, 0x9a, 0xb0, 0xea, 0xd3, 0x3b, 0x87, 0xc9, 0x19,
+        0x68, 0xa6, 0xe5, 0x09, 0xe1, 0x19, 0xff, 0x07, 0x78, 0x7b, 0x3e,
+        0xf4, 0x83, 0xe1, 0xdc, 0xdc, 0xcf, 0x6e, 0x30, 0x22};
+
+    digest = blake2b(filled, 64, filled_key, 64, 64);
+    assert_bytes(filled_answer, digest, 64);
+
+    free(digest);
+
+    printf("All tests have successfully passed!\n");
+}
+
+/**
+ * @brief main function
+ *
+ * @returns 0 on successful program exit
+ */
+int main()
+{
+    test();
     return 0;
 }