From 0993e9e14605533360e66c61ba00561665e9ae48 Mon Sep 17 00:00:00 2001
From: Acrimon <joel.wejdenstal@gmail.com>
Date: Wed, 13 May 2020 01:08:33 +0200
Subject: [PATCH] Fix #556

---
 server/Cargo.toml           |  2 +-
 server/src/auth_provider.rs | 24 +++++++-----------------
 2 files changed, 8 insertions(+), 18 deletions(-)

diff --git a/server/Cargo.toml b/server/Cargo.toml
index 128ca49644..165513ac2f 100644
--- a/server/Cargo.toml
+++ b/server/Cargo.toml
@@ -35,4 +35,4 @@ authc = { git = "https://gitlab.com/veloren/auth.git", rev = "65571ade0d954a0e0b
 libsqlite3-sys = { version = "0.9.1", features = ["bundled"] }
 diesel = { version = "1.4.3", features = ["sqlite"] }
 diesel_migrations = "1.4.0"
-dotenv = "0.15.0"
\ No newline at end of file
+dotenv = "0.15.0"
diff --git a/server/src/auth_provider.rs b/server/src/auth_provider.rs
index 03c3db9960..61623b6076 100644
--- a/server/src/auth_provider.rs
+++ b/server/src/auth_provider.rs
@@ -5,24 +5,14 @@ use log::error;
 use std::str::FromStr;
 
 fn derive_uuid(username: &str) -> Uuid {
-    let mut state: [u8; 16] = [
-        52, 17, 19, 239, 52, 17, 19, 239, 52, 17, 19, 239, 52, 17, 19, 239,
-    ];
-    for mix_byte_1 in username.as_bytes() {
-        for i in 0..16 {
-            let mix_byte_step: u8 = mix_byte_1
-                .wrapping_pow(239)
-                .wrapping_mul((i as u8).wrapping_pow(43));
-            let mix_byte_2 = state[(i + mix_byte_step as usize) % 16];
-            let rot_step: u8 = mix_byte_1
-                .wrapping_pow(29)
-                .wrapping_mul((i as u8).wrapping_pow(163));
-            state[i] = (state[i] ^ mix_byte_1)
-                .wrapping_mul(mix_byte_2)
-                .rotate_left(rot_step as u32);
-        }
+    let mut state = 144066263297769815596495629667062367629;
+
+    for byte in username.as_bytes() {
+        state ^= *byte as u128;
+        state = state.wrapping_mul(309485009821345068724781371);
     }
-    Uuid::from_slice(&state).unwrap()
+
+    Uuid::from_slice(&state.to_be_bytes()).unwrap()
 }
 
 pub struct AuthProvider {