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2026-08-21 21:46:23 -04:00 · 2026-05-27 20:51:32 -04:00
parent 981f3ea46e
commit 3eb755bc90
6 changed files with 151 additions and 12 deletions
@@ -0,0 +1,116 @@
+package de.caydenno1.xacrypto.hash.sha;
+
+import de.caydenno1.xacrypto.misc.Constants;
+
+import java.nio.charset.StandardCharsets;
+
+public class SHA0 {
+    // we really only need one file. very simple code
+    public static byte[] hash(byte[] data){
+        System.out.println("Beware, SHA0 is deprecated and cryptographically broken. Use at your own risk.");
+        byte[] padded = pad(data);
+
+        int a0 = Constants.SHA0_H[0], a1 = Constants.SHA0_H[1], a2 = Constants.SHA0_H[2], a3 = Constants.SHA0_H[3], a4 = Constants.SHA0_H[4];
+
+        int[] w = new int[80];
+
+        for (int i = 0 ; i < padded.length ; i += 64) {
+
+            for (int j = 0 ; j < 16 ; j++) {
+                int o = i + j * 4;
+                w[j] = ((padded[o] & 0xff) << 24)
+                        | ((padded[o + 1] & 0xff) << 16)
+                        | ((padded[o + 2] & 0xff) << 8)
+                        | (padded[o + 3] & 0xff);
+            }
+
+            for (int t = 16; t < 80; t++) {
+                w[t] = w[t-3] ^ w[t-8] ^ w[t-14] ^ w[t-16];
+            }
+
+            int a = a0, b = a1, c = a2, d = a3, e = a4;
+
+            for (int t = 0 ; t < 80 ; t++) {
+                int f, k;
+
+                if (t < 20) {
+                    f = (b & c);
+                    k = Constants.SHA0_K[0];
+                } else if (t < 40) {
+                    f = b ^ c ^ d;
+                    k = Constants.SHA0_K[1];
+                } else if (t < 60) {
+                    f = (b & c) | (b & d) | (c & d);
+                    k = Constants.SHA0_K[2];
+                } else {
+                    f = b ^ c ^ d;
+                    k = Constants.SHA0_K[3];
+                }
+
+                int temp = de.caydenno1.xacrypto.hash.ROT.ROTL(a, 5);
+                temp += f;
+                temp += e;
+                temp += k;
+                temp += w[t];
+
+                e = d;
+                d = c;
+                c = de.caydenno1.xacrypto.hash.ROT.ROTL(b, 30);
+                b = a;
+                a = temp;
+            }
+
+            a0 += a;
+            a1 += b;
+            a2 += c;
+            a3 += d;
+            a4 += e;
+        }
+
+        return INT2BYTE(a0, a1, a2, a3, a4);
+    }
+
+    public static String hash(String data) {
+        byte[] result = hash(data.getBytes(StandardCharsets.UTF_8));
+        return hex(result);
+    }
+
+    public static String hex(byte[] data) {
+        StringBuilder builder = new StringBuilder();
+        for (byte b : data) builder.append(String.format("%02x", b));
+        return builder.toString();
+    }
+
+    private static byte[] pad(byte[] mesg) {
+        int len = mesg.length;
+        long bit = (long) len * 8;
+
+        int padL = (64 - ((len + 9) % 64)) % 64;
+        byte[] o = new byte[len+padL+9];
+
+        System.arraycopy(mesg,0,o,0,len);
+        o[len] = (byte) 0x80;
+        for (int i = 0; i < 8; i++) {
+            o[o.length - (i+1)] = (byte) (bit >>> (8*i));
+        }
+
+        return o;
+    }
+
+    private static byte[] INT2BYTE(int a,int b,int c,int d,int e) {
+        byte[] out = new byte[20];
+        write(a, out, 0);
+        write(b, out, 4);
+        write(c, out, 8);
+        write(d, out, 12);
+        write(e, out, 16);
+        return out;
+    }
+
+    private static void write(int v, byte[] o, int i) {
+        o[i  ] = (byte)(v >>> 24);
+        o[i+1] = (byte)(v >>> 16);
+        o[i+2] = (byte)(v >>>  8);
+        o[i+3] = (byte)(v       );
+    }
+}