swift-re常见的加密解密

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 2024/10/09 

swift-re常见的加密解密

在xcode里用swift写了点加密解密，以后都放着这里了。。

RC4

import Foundation
class RC4 {
    var state = [UInt8](repeating: 0, count: 256)
    init(key: [UInt8]) {
        var j:Int = 0
        for i in 0..<256 {
            state[i] = UInt8(i)
        }
        for i in 0..<256 {
            j = (j + Int(state[i]) + Int(key[i % key.count])) % 256
            state.swapAt(i, j)
        }
    }
    func encrypt(data: inout [UInt8]){
        var x: Int = 0
        var y: Int = 0
        for i in 0..<data.count {
            x = (x + 1) % 256
            y = (y + Int(state[x])) % 256
            let temp = state[x]
            state[x]=state[y]
            state[y]=temp
            let t = state[(Int(state[x]) + Int(state[y])) % 256]
            data[i] = data[i] ^ t
            
        }
    }
}
let key: [UInt8] = Array("qwq".utf8)
let rc4=RC4(key: key)
var text: [UInt8] = Array("straw".utf8)
rc4.encrypt(data: &text)
for i in 0..<text.count{
    var texthex=String(format: "0x%02x", text[i])
    print("\(texthex)")
}

TEA

加密

import Foundation
var flag: String = "liufeiyu"
var hexArray:[UInt8?]=[]
for ch in flag{
    hexArray.append(ch.asciiValue)
}
var v0:UInt32
var v1:UInt32
var sum:UInt32 = 0
//print(hexArray)
var I32Array:[UInt32]=[]
for i in stride(from: 0, to: hexArray.count, by: 4) {
    let byte1 = UInt32(hexArray[i]!)
    let byte2 = UInt32(hexArray[i + 1]!) << 8
    let byte3 = UInt32(hexArray[i + 2]!) << 16
    let byte4 = UInt32(hexArray[i + 3]!) << 24
    I32Array.append(byte1 | byte2 | byte3 | byte4)
}
print(I32Array)
let key: [UInt32] = [0x1,0x1,0x4,0x5]
for i in 0..<I32Array.count/2{
    v0=I32Array[2*i]
    v1=I32Array[2*i+1];
    for _ in 0..<32 {
        sum = UInt32((UInt64(sum) + UInt64(0x9e3779b9)) & 0xFFFFFFFF)
        v0 &+= UInt32((((UInt64(v1) << 4) + UInt64(key[0])) ^ (UInt64(v1) + UInt64(sum)) ^ ((UInt64(v1) >> 5) + UInt64(key[1])))&0xFFFFFFFF)
        v1 &+= UInt32((((UInt64(v0) << 4) + UInt64(key[2])) ^ (UInt64(v0) + UInt64(sum)) ^ ((UInt64(v0) >> 5) + UInt64(key[3])))&0xFFFFFFFF)
    }
    I32Array[2*i]=v0
    I32Array[2*i+1]=v1
}
print(I32Array)

还没包装，等后面有时间包装一下

解密

import Foundation
let key: [UInt32] = [0x1,0x1,0x4,0x5]
var pw: [UInt32] = [0x5f031f51,0xae732304,0xa6bdef67,0x15c0218b,0x4ec46f64,0x8bfccb46,0x90eebc4a,0xa9aa0c03 ]
var v0:UInt32
var v1:UInt32
var sum:UInt32 = 0
for i in 0..<pw.count/2{
    v0=pw[2*i]
    v1=pw[2*i+1];
    sum=UInt32(UInt64(32*0x9E3779B9)&0xFFFFFFFF)
    for _ in 0..<32 {
        v1 &-= UInt32((((UInt64(v0) << 4) + UInt64(key[2])) ^ (UInt64(v0) + UInt64(sum)) ^ ((UInt64(v0) >> 5) + UInt64(key[3])))&0xFFFFFFFF)
//        print(v1)
        v0 &-= UInt32((((UInt64(v1) << 4) + UInt64(key[0])) ^ (UInt64(v1) + UInt64(sum)) ^ ((UInt64(v1) >> 5) + UInt64(key[1])))&0xFFFFFFFF)
//        print(v0)
        sum = UInt32((UInt64(sum) + UInt64(0x61C88647)) & 0xFFFFFFFF)
//        print(sum)
            }
    for j in 0...3{
        var v0hex=String(format: "%c", (v0>>(j*8))&0xff)
        print(v0hex,terminator: "")
    }
    for j in 0...3{
        var v1hex=String(format: "%c", (v1>>(j*8))&0xff)
        print(v1hex,terminator: "")
    }
}

被swift的检测恶心了，数据溢出或者类型不匹配直接报错，必须全加一遍类型修正。

原文作者：Straw

原文链接：https://straw-233.github.io/2024/10/09/swift-re%E5%B8%B8%E8%A7%81%E7%9A%84%E5%8A%A0%E5%AF%86%E8%A7%A3%E5%AF%86/

发表日期：October 9th 2024, 8:29:28 pm

更新日期：October 13th 2024, 6:41:57 pm

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CATALOG

1. swift-re常见的加密解密
1. 1.1. RC4
2. 1.2. TEA
  1. 1.2.1. 加密
  2. 1.2.2. 解密