如何在 Go 中实现无填充的 AES-ECB 加密？

package main

import (
    "crypto/aes"
    "encoding/base64"
    "log"
)

func AesEncryptECB(origData []byte, key []byte) string {
    cipher, _ := aes.NewCipher(generateKey(key))
    length := (len(origData) + aes.BlockSize) / aes.BlockSize
    plain := make([]byte, length*aes.BlockSize)
    copy(plain, origData)

    encrypted := make([]byte, len(plain))
    // Block encryption
    for bs, be := 0, cipher.BlockSize(); bs <= len(origData); bs, be = bs+cipher.BlockSize(), be+cipher.BlockSize() {
        cipher.Encrypt(encrypted[bs:be], plain[bs:be])
    }

    return base64.StdEncoding.EncodeToString(encrypted)
}

func AesDecryptECB(str string, key []byte) (decrypted []byte) {
    encrypted, _ := base64.StdEncoding.DecodeString(str)

    cipher, _ := aes.NewCipher(generateKey(key))
    decrypted = make([]byte, len(encrypted))
    for bs, be := 0, cipher.BlockSize(); bs < len(encrypted); bs, be = bs+cipher.BlockSize(), be+cipher.BlockSize() {
        cipher.Decrypt(decrypted[bs:be], encrypted[bs:be])
    }

    trim := 0
    if len(decrypted) > 0 {
        trim = len(decrypted) - int(decrypted[len(decrypted)-1])
    }
    return decrypted[:trim]
}

func generateKey(key []byte) (genKey []byte) {
    genKey = make([]byte, 16)
    copy(genKey, key)
    for i := 16; i < len(key); {
        for j := 0; j < 16 && i < len(key); j, i = j+1, i+1 {
            genKey[j] ^= key[i]
        }
    }
    return genKey
}

func main() {
    origin := []byte("406BF0AD11310101220213481000320000")
    key := []byte("ER2Fb6ts3ECX")

    encrypted := AesEncryptECB(origin, key)
    log.Println("encrypted: ", encrypted)
    decrypted := AesDecryptECB(encrypted, key)
    log.Println("decrypted: ", string(decrypted))
}