commit 3c308ccb2107ae68f1660f3a0676d532c1b2ddc1
Author: afonya2 <adamhir@freemail.hu>
Date:   Thu May 15 17:24:37 2025 +0200

    hello git

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..0f634cf
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,3 @@
+package-lock.json
+node_modules/
+test.txt
\ No newline at end of file
diff --git a/IGA.ts b/IGA.ts
new file mode 100644
index 0000000..a616cb1
--- /dev/null
+++ b/IGA.ts
@@ -0,0 +1,209 @@
+type padding = {
+    padding: number[]
+    seed: number
+}
+
+type verifyOut = {
+    valid: boolean
+    reason: string
+}
+
+function modMul(n: number, x: number, m: number): number {
+    let out = 0
+    for (let i = 0; i < x; i++) {
+        out = out + n
+        out = out % m
+    }
+    return out
+}
+
+class randomGenerator {
+    state = 0
+    seen: number[] = []
+    constructor(seed: number) {
+        this.state = seed
+    }
+
+    next(): number {
+        let temp = modMul(this.state, 6967, 65536)
+        if (this.seen.length >= 65536) {
+            this.seen = []
+        }
+        while (this.seen.includes(temp)) {
+            temp++
+            temp = temp % 65536
+        }
+        this.seen.push(temp)
+        this.state = temp
+        return this.state
+    }
+}
+
+function generatePadding(len: number, seed?: number): padding {
+    if (seed == undefined) {
+        seed = Math.floor(Math.random() * 65535)
+    }
+    let out: number[] = []
+    let generator = new randomGenerator(seed)
+    for (let i = 0; i < len; i++) {
+        let n = generator.next()
+        out.push(n)
+    }
+    return {
+        padding: out,
+        seed: seed
+    }
+}
+
+function copy(input: number[]): number[] {
+    let out: number[] = []
+    for (let i = 0; i < input.length; i++) {
+        out[i] = input[i]
+    }
+    return out
+}
+
+function dec2bin(dec: number): string {
+    return (dec >>> 0).toString(2);
+}
+function bin2dec(bin: string): number {
+    return parseInt(bin, 2)
+}
+function fixbin(bin: string, len: number): string {
+    let out = bin
+    while (out.length < len) {
+        out = "0" + out
+    }
+    return out.substring(out.length-len, out.length)
+}
+function bin2hex(bin: string): string {
+    let chars = ["0","1","2","3","4","5","6","7","8","9","A","B","C","D","E","F"]
+    let hex = ""
+    while (bin.length > 3) {
+        let n = bin2dec(bin.substring(0, 4))
+        hex += chars[n]
+        bin = bin.substring(4, bin.length)
+    }
+    return hex
+}
+function hex2bin(hex: string): string {
+    let chars = ["0","1","2","3","4","5","6","7","8","9","A","B","C","D","E","F"]
+    let bin = ""
+    for (let i = 0; i < hex.length; i++) {
+        bin += fixbin(dec2bin(chars.indexOf(hex[i].toUpperCase())), 4)        
+    }
+    return bin
+}
+
+function checksum(input: string) {
+    let state: string[] = []
+    for (let i = 0; i < 16; i++) {
+        state.push("0")
+    }
+    let bin = ""
+    for (let i = 0; i < input.length; i++) {
+        bin += dec2bin(input.charCodeAt(i))
+    }
+    while (bin.length > 0) {
+        state.splice(0, 1)
+        state.push(bin[0])
+        if (state[0] == "1") {
+            state[8] = state[8] == "1" ? "0" : "1"
+            state[6] = state[6] == "1" ? "0" : "1"
+            state[1] = state[1] == "1" ? "0" : "1"
+        }
+        bin = bin.substring(1, bin.length)
+    }
+    return state.join("")
+}
+
+function hash(input: string, salt: number = 0, iterations: number = 32, len: number = 32, seed?: number): string {
+    if (len*4%16 != 0) {
+        throw new Error("Invalid length")
+    }
+    if (len < 16) {
+        throw new Error("Length must be at least 16")
+    }
+    const padding = generatePadding(len, seed);
+    let hash: number[] = []
+    for (let i = 0; i < padding.padding.length; i++) {
+        hash[i] = padding.padding[i]
+    }
+    let plus = hash.length
+    for (let i = 0; i < input.length; i++) {
+        hash[plus+i] = input.charCodeAt(i)
+    }
+    for (let i = 0; i < iterations; i++) {
+        let state = copy(hash)
+        for (let ii = 0; ii < hash.length; ii++) {
+            let temp = state[ii] + (state[ii+1] ? state[ii+1] : state[0]) + salt
+            while (temp > 65536) {
+                temp -= i==0 ? 2411 : (state[ii-1] ? state[ii-1] : state[state.length-1])
+            }
+            hash[ii] = temp
+        }
+    }
+    const pSeed = fixbin(dec2bin(padding.seed), 16)
+    let sumAdd = ""
+    for (let i = 0; sumAdd.length < 16 && i < padding.padding.length; i++) {
+        sumAdd += padding.padding[i].toString(16)
+    }
+    sumAdd = sumAdd.substring(0, 16).toUpperCase()
+    const sum = checksum(input + sumAdd)
+    let bin = ""
+    for (let i = 0; bin.length < len*4-32; i++) {
+        bin += hash[i] ? fixbin(dec2bin(hash[i]), 16) : "0000000000000000"
+    }
+    const outBin = pSeed + bin + sum
+    const out = bin2hex(outBin)
+    return out
+}
+
+function verifyHash(input: string, inHash: string, salt: number = 0, iterations: number = 32, len: number = 32): verifyOut {
+    if (len*4%16 != 0) {
+        throw new Error("Invalid length")
+    }
+    if (len < 16) {
+        throw new Error("Length must be at least 16")
+    }
+    if (inHash.length != len) {
+        throw new Error("The hash is not " + len + " long")
+    }
+    const hBin = hex2bin(inHash)
+    const pSeed = bin2dec(hBin.substring(0, 16))
+    const inSum = hBin.substring(hBin.length-16, hBin.length)
+    const padding = generatePadding(len, pSeed);
+    let sumAdd = ""
+    for (let i = 0; sumAdd.length < 16 && i < padding.padding.length; i++) {
+        sumAdd += padding.padding[i].toString(16)
+    }
+    sumAdd = sumAdd.substring(0, 16).toUpperCase()
+    const sum = checksum(input + sumAdd)
+    if (inSum != sum) {
+        return {
+            valid: false,
+            reason: "Checksum does not match"
+        }
+    }
+    const verifyHash = hash(input, salt, iterations, len, pSeed)
+    if (inHash == verifyHash) {
+        return {
+            valid: true,
+            reason: ""
+        }
+    } else {
+        return {
+            valid: false,
+            reason: "Hash does not match"
+        }
+    }
+}
+
+export default {
+    hash,
+    verifyHash
+}
+
+export type {
+    verifyOut
+}
\ No newline at end of file
diff --git a/hash.ts b/hash.ts
new file mode 100644
index 0000000..97ef32f
--- /dev/null
+++ b/hash.ts
@@ -0,0 +1,62 @@
+import IGA from './IGA';
+import fs from 'fs';
+
+const args = process.argv.slice(2)
+const version = "1.1"
+
+function printHelp() {
+    console.log("IGA commandline tool v" + version)
+    console.log("Usage: tsx hash.ts <hash|verify> <input file> [<hash to verify>] [options]");
+    console.log("Options:");
+    console.log("[<salt = 0>] [<iterations = 32>] [<length of the hash = 32>]");
+}
+
+if (args[0] == "hash") {
+    if (args.length < 2) {
+        console.log("Not enough arguments");
+        printHelp()
+        process.exit(0)
+    }
+    if (!fs.existsSync(args[1])) {
+        console.log("File not found: " + args[1])
+        process.exit(0)
+    }
+    let fileData = fs.readFileSync(args[1], 'utf8');
+    let salt = args[2] ? parseInt(args[2]) : 0
+    let iterations = args[3] ? parseInt(args[3]) : 32
+    let len = args[4] ? parseInt(args[4]) : 32
+    try {
+        let hash = IGA.hash(fileData, salt, iterations, len)
+        console.log(hash)
+    } catch (e) {
+        console.error("Error while creating hash: " + e.stack)
+    }
+} else if (args[0] == "verify") {
+    if (args.length < 3) {
+        console.log("Not enough arguments");
+        printHelp()
+        process.exit(0)
+    }
+    if (!fs.existsSync(args[1])) {
+        console.log("File not found: " + args[1])
+        process.exit(0)
+    }
+    let fileData = fs.readFileSync(args[1], 'utf8');
+    let hashToVerify = args[2]
+    let salt = args[3] ? parseInt(args[3]) : 0
+    let iterations = args[4] ? parseInt(args[4]) : 32
+    let len = args[5] ? parseInt(args[5]) : 32
+    try {
+        let verify = IGA.verifyHash(fileData, hashToVerify, salt, iterations, len)
+        if (verify.valid) {
+            console.log("Hash is valid!")
+        } else {
+            console.log("Hash is invalid!")
+            console.log("Reason: " + verify.reason)
+        }
+    } catch (e) {
+        console.error("Error while verifying hash: " + e.stack)
+    }
+} else {
+    printHelp()
+}
\ No newline at end of file
diff --git a/package.json b/package.json
new file mode 100644
index 0000000..38561a6
--- /dev/null
+++ b/package.json
@@ -0,0 +1,5 @@
+{
+  "dependencies": {
+    "@types/node": "^22.15.17"
+  }
+}