diff --git a/src/libsodium/crypto_generichash/blake2/ref/generichash_blake2b.c b/src/libsodium/crypto_generichash/blake2/ref/generichash_blake2b.c
index bd2c795f..8329ba38 100644
--- a/src/libsodium/crypto_generichash/blake2/ref/generichash_blake2b.c
+++ b/src/libsodium/crypto_generichash/blake2/ref/generichash_blake2b.c
@@ -7,10 +7,9 @@
 #include "blake2.h"
 
 int
-crypto_generichash_blake2b(unsigned char *out, const unsigned char *in,
-                           const unsigned char *key,
-                           size_t outlen, unsigned long long inlen,
-                           size_t keylen)
+crypto_generichash_blake2b(unsigned char *out, size_t outlen,
+                           const unsigned char *in, unsigned long long inlen,
+                           const unsigned char *key, size_t keylen)
 {
     if (outlen <= 0U || outlen > BLAKE2B_OUTBYTES ||
         keylen > BLAKE2B_KEYBYTES || inlen > UINT64_MAX) {
@@ -26,8 +25,7 @@ crypto_generichash_blake2b(unsigned char *out, const unsigned char *in,
 int
 crypto_generichash_blake2b_init(crypto_generichash_blake2b_state *state,
                                 const unsigned char *key,
-                                const size_t keylen,
-                                const size_t outlen)
+                                const size_t keylen, const size_t outlen)
 {
     if (outlen <= 0U || outlen > BLAKE2B_OUTBYTES ||
         keylen > BLAKE2B_KEYBYTES) {
diff --git a/src/libsodium/crypto_generichash/crypto_generichash.c b/src/libsodium/crypto_generichash/crypto_generichash.c
index b4ba0671..541eec80 100644
--- a/src/libsodium/crypto_generichash/crypto_generichash.c
+++ b/src/libsodium/crypto_generichash/crypto_generichash.c
@@ -2,11 +2,11 @@
 #include "crypto_generichash.h"
 
 int
-crypto_generichash(unsigned char *out, const unsigned char *in,
-                   const unsigned char *key,
-                   size_t outlen, unsigned long long inlen, size_t keylen)
+crypto_generichash(unsigned char *out, size_t outlen, const unsigned char *in,
+                   unsigned long long inlen, const unsigned char *key,
+                   size_t keylen)
 {
-    return crypto_generichash_blake2b(out, in, key, outlen, inlen, keylen);
+    return crypto_generichash_blake2b(out, outlen, in, inlen, key, keylen);
 }
 
 int
diff --git a/src/libsodium/include/sodium/crypto_generichash.h b/src/libsodium/include/sodium/crypto_generichash.h
index 77212338..e9b082b4 100644
--- a/src/libsodium/include/sodium/crypto_generichash.h
+++ b/src/libsodium/include/sodium/crypto_generichash.h
@@ -11,10 +11,9 @@
 
 typedef crypto_generichash_blake2b_state crypto_generichash_state;
 
-int crypto_generichash(unsigned char *out, const unsigned char *in,
-                       const unsigned char *key,
-                       size_t outlen, unsigned long long inlen,
-                       size_t keylen);
+int crypto_generichash(unsigned char *out, size_t outlen,
+                       const unsigned char *in, unsigned long long inlen,
+                       const unsigned char *key, size_t keylen);
 
 int crypto_generichash_init(crypto_generichash_blake2b_state *state,
                             const unsigned char *key,
diff --git a/src/libsodium/include/sodium/crypto_generichash_blake2b.h b/src/libsodium/include/sodium/crypto_generichash_blake2b.h
index 1dba21fe..a8a15d62 100644
--- a/src/libsodium/include/sodium/crypto_generichash_blake2b.h
+++ b/src/libsodium/include/sodium/crypto_generichash_blake2b.h
@@ -30,17 +30,14 @@ CRYPTO_ALIGN(64) typedef struct {
 #ifdef __cplusplus
 extern "C" {
 #endif
-int crypto_generichash_blake2b_ref(unsigned char *out,
+int crypto_generichash_blake2b_ref(unsigned char *out, size_t outlen,
                                    const unsigned char *in,
-                                   const unsigned char *key,
-                                   size_t outlen,
                                    unsigned long long inlen,
-                                   size_t keylen);
+                                   const unsigned char *key, size_t keylen);
 
 int crypto_generichash_blake2b_init(crypto_generichash_blake2b_state *state,
                                     const unsigned char *key,
-                                    const size_t keylen,
-                                    const size_t outlen);
+                                    const size_t keylen, const size_t outlen);
 
 int crypto_generichash_blake2b_update(crypto_generichash_blake2b_state *state,
                                       const unsigned char *in,
diff --git a/test/default/generichash.c b/test/default/generichash.c
index 61fe7b9e..26cc2d05 100644
--- a/test/default/generichash.c
+++ b/test/default/generichash.c
@@ -15,8 +15,9 @@ int main(void)
 
     for(i = 0; i < MAXLEN; ++i) {
         in[i]=i;
-        crypto_generichash(out, in, k, 1 + i % crypto_generichash_BYTES_MAX,
-                           i, 1 + i % crypto_generichash_KEYBYTES_MAX);
+        crypto_generichash(out, 1 + i % crypto_generichash_BYTES_MAX,
+                           in, i,
+                           k, 1 + i % crypto_generichash_KEYBYTES_MAX);
         for (j = 0;j < 1 + i % crypto_generichash_BYTES_MAX;++j) {
             printf("%02x",(unsigned int) out[j]);
         }