refactor package structure

2025-11-09 20:03:49 +01:00
parent c14269e0c6
commit 88d673922a
8 changed files with 38 additions and 21 deletions
--- a/src/commonMain/kotlin/com/infendro/hash/sha1/SHA1.kt
+++ b/src/commonMain/kotlin/com/infendro/hash/sha1/SHA1.kt
@@ -0,0 +1,85 @@
+package com.infendro.hash.sha1
+
+import com.infendro.bytearray.addAll
+import com.infendro.bytearray.toByteArray
+import com.infendro.bytearray.toUIntArray
+import com.infendro.hash.HashFunction
+
+@Suppress("UNUSED")
+object SHA1 : HashFunction() {
+    override val bytes: Int
+        get() = 20
+
+    override fun hash(
+        value: ByteArray,
+    ): ByteArray {
+        var h0 = 0x67452301U
+        var h1 = 0xefcdaB89U
+        var h2 = 0x98badcfeU
+        var h3 = 0x10325476U
+        var h4 = 0xc3d2e1f0U
+        val ml = value.size.toULong() * 8UL
+
+        val paddedValue = buildList {
+            addAll(value)
+            add(0x80.toByte())
+            while (size % 64 != 56) {
+                add(0x00.toByte())
+            }
+            addAll(ml.toByteArray())
+        }
+
+        val chunks = paddedValue
+            .chunked(64)
+        for (chunk in chunks) {
+            val w = buildList {
+                addAll(chunk.toUIntArray())
+                for (i in 16..<80) {
+                    val word = (get(i - 3) xor get(i - 8) xor get(i - 14) xor get(i - 16)).rotateLeft(1)
+                    add(word)
+                }
+            }
+
+            var a = h0
+            var b = h1
+            var c = h2
+            var d = h3
+            var e = h4
+
+            for (i in 0..<80) {
+                val f = when (i) {
+                    in 0..<20 -> (b and c) or (b.inv() and d)
+                    in 20..<40 -> b xor c xor d
+                    in 40..<60 -> (b and c) or (b and d) or (c and d)
+                    else -> b xor c xor d
+                }
+                val k = when (i) {
+                    in 0..<20 -> 0x5a827999U
+                    in 20..<40 -> 0x6ed9eba1U
+                    in 40..<60 -> 0x8f1bbcdcU
+                    else -> 0xca62c1d6U
+                }
+                val temp = a.rotateLeft(5) + f + e + k + w[i]
+                e = d
+                d = c
+                c = b.rotateLeft(30)
+                b = a
+                a = temp
+            }
+
+            h0 += a
+            h1 += b
+            h2 += c
+            h3 += d
+            h4 += e
+        }
+
+        return byteArrayOf(
+            *h0.toByteArray(),
+            *h1.toByteArray(),
+            *h2.toByteArray(),
+            *h3.toByteArray(),
+            *h4.toByteArray(),
+        )
+    }
+}