Fix endianness of IPv6

holepunchto · Oct 26, 2021 · e6b5682 · e6b5682
1 parent 32dc030
commit e6b5682
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Showing 2 changed files with 15 additions and 15 deletions.
diff --git a/index.js b/index.js
@@ -47,14 +47,14 @@ const ipv6 = {
   decode (state) {
     if (state.end - state.start < 16) throw new Error('Out of bounds')
     return (
-      c.uint16.decode(state).toString(16) + ':' +
-      c.uint16.decode(state).toString(16) + ':' +
-      c.uint16.decode(state).toString(16) + ':' +
-      c.uint16.decode(state).toString(16) + ':' +
-      c.uint16.decode(state).toString(16) + ':' +
-      c.uint16.decode(state).toString(16) + ':' +
-      c.uint16.decode(state).toString(16) + ':' +
-      c.uint16.decode(state).toString(16)
+      (state.buffer[state.start++] * 256 + state.buffer[state.start++]).toString(16) + ':' +
+      (state.buffer[state.start++] * 256 + state.buffer[state.start++]).toString(16) + ':' +
+      (state.buffer[state.start++] * 256 + state.buffer[state.start++]).toString(16) + ':' +
+      (state.buffer[state.start++] * 256 + state.buffer[state.start++]).toString(16) + ':' +
+      (state.buffer[state.start++] * 256 + state.buffer[state.start++]).toString(16) + ':' +
+      (state.buffer[state.start++] * 256 + state.buffer[state.start++]).toString(16) + ':' +
+      (state.buffer[state.start++] * 256 + state.buffer[state.start++]).toString(16) + ':' +
+      (state.buffer[state.start++] * 256 + state.buffer[state.start++]).toString(16)
     )
   }
 }
@@ -106,8 +106,8 @@ function encodeIPv6 (state, string) {
       else if (c >= 0x61 && c <= 0x66) n = n * 0x10 + (c - /* a */ 0x61 + 10)
     }
 
-    state.buffer[state.start++] = n
     state.buffer[state.start++] = n >>> 8
+    state.buffer[state.start++] = n
 
     if (i < string.length && string.charCodeAt(i) === /* : */ 0x3a) {
       i++

diff --git a/test.mjs b/test.mjs
@@ -21,27 +21,27 @@ test('ipv4', (t) => {
 
 test('ipv6', (t) => {
   const ip = '1:2:3:4:5:6:7:8'
-  const buf = Buffer.from([1, 0, 2, 0, 3, 0, 4, 0, 5, 0, 6, 0, 7, 0, 8, 0])
+  const buf = Buffer.from([0, 1, 0, 2, 0, 3, 0, 4, 0, 5, 0, 6, 0, 7, 0, 8])
 
   t.alike(c.encode(ipv6, ip), buf)
   t.alike(c.decode(ipv6, buf), ip)
 
   t.test('abbreviated', (t) => {
-    const buf = Buffer.from([1, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 7, 0, 8, 0])
+    const buf = Buffer.from([0, 1, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 7, 0, 8])
 
     t.alike(c.encode(ipv6, '1:2::7:8'), buf)
     t.alike(c.decode(ipv6, buf), '1:2:0:0:0:0:7:8')
   })
 
   t.test('prefix abbreviated', (t) => {
-    const buf = Buffer.from([0, 0, 0, 0, 0, 0, 0, 0, 5, 0, 6, 0, 7, 0, 8, 0])
+    const buf = Buffer.from([0, 0, 0, 0, 0, 0, 0, 0, 0, 5, 0, 6, 0, 7, 0, 8])
 
     t.alike(c.encode(ipv6, '::5:6:7:8'), buf)
     t.alike(c.decode(ipv6, buf), '0:0:0:0:5:6:7:8')
   })
 
   t.test('suffix abbreviated', (t) => {
-    const buf = Buffer.from([1, 0, 2, 0, 3, 0, 4, 0, 0, 0, 0, 0, 0, 0, 0, 0])
+    const buf = Buffer.from([0, 1, 0, 2, 0, 3, 0, 4, 0, 0, 0, 0, 0, 0, 0, 0])
 
     t.alike(c.encode(ipv6, '1:2:3:4::'), buf)
     t.alike(c.decode(ipv6, buf), '1:2:3:4:0:0:0:0')
@@ -55,14 +55,14 @@ test('ipv6', (t) => {
   })
 
   t.test('lowercase hex', (t) => {
-    const buf = Buffer.from([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xcd, 0xab])
+    const buf = Buffer.from([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xab, 0xcd])
 
     t.alike(c.encode(ipv6, '::abcd'), buf)
     t.alike(c.decode(ipv6, buf), '0:0:0:0:0:0:0:abcd')
   })
 
   t.test('uppercase hex', (t) => {
-    const buf = Buffer.from([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xcd, 0xab])
+    const buf = Buffer.from([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xab, 0xcd])
 
     t.alike(c.encode(ipv6, '::ABCD'), buf)
     t.alike(c.decode(ipv6, buf), '0:0:0:0:0:0:0:abcd')