package main
import (
"fmt"
"time"
"net/http"
"strconv"
"io/ioutil"
"encoding/json"
"errors"
"crypto/rsa"
"crypto/rand"
//"math/big"
)
func main() {
if err := Login("username", "password"); err != nil {
fmt.Println(err)
}
}
func Login(username, password string) error {
doNotCache := strconv.FormatInt(time.Now().UnixNano() / int64(time.Millisecond), 10)
// Get RSA Key
resp, err := http.PostForm("https://steamcommunity.com/login/getrsakey/", map[string][]string{
"donotcache": {doNotCache},
"username": {username},
})
if err != nil {
return err
}
content, err := ioutil.ReadAll(resp.Body)
if err != nil {
return err
}
var decoded map[string]interface{}
err = json.Unmarshal(content, &decoded)
if err != nil {
return err
}
if decoded["success"] != true {
return errors.New("Failed to retrieve RSA key.")
}
// Set encryption variables
var privateKey *rsa.PrivateKey
var publicKey *rsa.PublicKey
var plain_text, encrypted []byte
plain_text = []byte(password)
// Generate Private Key
if privateKey, err = rsa.GenerateKey(rand.Reader, 1024); err != nil {
return err
}
privateKey.Precompute()
if err = privateKey.Validate(); err != nil {
return err
}
publicKey.N = decoded["publickey_mod"].(string) // <- This is not right, I need to create a modulus from the publickey_mod string and it needs to be of type big.Int
publicKey.E = decoded["publickey_exp"].(int)
encrypted, err = rsa.EncryptPKCS1v15(rand.Reader, publicKey, plain_text)
if err != nil {
return err
}
fmt.Printf("PKCS1 Encrypted [%s] to \n[%x]\n", string(plain_text), encrypted)
return nil
}

$key = array(
'n' => new Math_BigInteger($curl->response->publickey_mod,16),
'e' => new Math_BigInteger($curl->response->publickey_exp,16)
);
// Define exponent
define('CRYPT_RSA_EXPONENT', 010001);
// Load the key
$rsa->loadKey($key)
// Set settings
$rsa->setEncryptionMode(CRYPT_RSA_ENCRYPTION_PKCS1);
$rsa->setHash('sha256');
// Encrypt password
$encrypted_password = base64_encode($rsa->encrypt($password));

publicKey.N, _ = new(big.Int).SetString(decoded["publickey_mod"].(string), 16 /* = base 16 */)
// json numbers are float64 by default unless you use a struct and force a type
publicKey.E = int(decoded["publickey_exp"].(float64))