使用VB.NET+SRP6实现魔兽世界账号注册的密码验证问题求助

核心问题排查 #

1. SQL参数绑定错误：原代码中SQL语句的第三个字段是salt，但参数误用了@pass，还错误地在加密关闭时传入明文密码——AzerothCore的account表采用SRP6验证机制，仅需存储salt和verifier，不需要明文密码。
2. SRP6算法BigInteger处理缺陷：字节数组转BigInteger时未处理符号位问题，导致计算出的verifier不符合游戏端验证规则。

修复后的代码 #

1. RegisterUser方法修复 #

Public Sub RegisterUser()
    Dim conStr = "Server=" + Data.Settings.MySQLServerHost + ";Uid=" + Data.Settings.MySQLServerUser + ";Database=" + Data.Settings.AuthDatabase + ";Port=" + Data.Settings.MySQLServerPort + ";Pwd=" + Data.Settings.MySQLServerPassword + ";"
    Dim salt(31) As Byte
    Using rng As New RNGCryptoServiceProvider()
        rng.GetBytes(salt)
    End Using
    ' 计算SRP6验证值
    Dim verifier As Byte() = SRP6.CalculateSRP6Verifier(TextAccountCreateName.Text, TextAccountPasswordCreate.Text, salt)

    Try
        Using conn As New MySqlConnection(conStr)
            Using cmd As New MySqlCommand()
                cmd.Connection = conn
                Select Case Data.Settings.SelectedCore
                    Case Cores.AzerothCore
                        ' 修正参数与字段的对应关系，移除错误的明文密码逻辑
                        cmd.CommandText = "INSERT INTO account (username, email, salt, verifier) VALUES (@user,@ema,@salt,@verif)"
                        cmd.Parameters.AddWithValue("@user", TextAccountCreateName.Text.ToUpper()) ' 强制存储大写用户名
                        cmd.Parameters.AddWithValue("@ema", TextAccountEmailCreate.Text)
                        cmd.Parameters.AddWithValue("@salt", salt)
                        cmd.Parameters.AddWithValue("@verif", verifier)
                    Case Else
                        Exit Sub
                End Select
                conn.Open()
                cmd.ExecuteNonQuery()
            End Using
        End Using
    Catch ex As Exception
        MsgBox(ex.Message)
    End Try
End Sub

2. SRP6类修复 #

Imports System.Security.Cryptography
Imports System.Numerics
Public Class SRP6
    Public Shared Function CalculateSRP6Verifier(ByVal username As String, ByVal password As String, ByVal salt As Byte()) As Byte()
        ' AzerothCore标准SRP6常量
        Dim g As BigInteger = 7
        Dim N As BigInteger = BigInteger.Parse("894B645E89E1535BBDAD5B8B290650530801B18EBFBF5E8FAB3C82872A3E9BB7", Globalization.NumberStyles.HexNumber)
        
        ' 1. 计算H1 = SHA1(大写用户名:大写密码)
        Dim h1 As Byte() = SHA1.Create().ComputeHash(Text.Encoding.UTF8.GetBytes(username.ToUpper() & ":" & password.ToUpper()))
        
        ' 2. 计算H2 = SHA1(salt + H1)
        Dim h2 As Byte() = SHA1.Create().ComputeHash(salt.Concat(h1).ToArray())
        
        ' 3. 将H2转为无符号BigInteger（添加0字节避免符号位干扰）
        Dim h2Bytes = h2.Reverse().Concat({CByte(0)}).ToArray()
        Dim h2Int As New BigInteger(h2Bytes)
        
        ' 4. 计算verifier = g^H2 mod N
        Dim verifier As BigInteger = BigInteger.ModPow(g, h2Int, N)
        
        ' 5. 将verifier转为32字节大端格式（匹配AzerothCore存储要求）
        Dim verifierBytes = verifier.ToByteArray()
        ' 移除可能存在的符号位字节
        If verifierBytes.Length > 32 Then
            Array.Resize(verifierBytes, 32)
        End If
        ' 反转并补全到32字节
        verifierBytes = verifierBytes.Reverse().ToArray()
        If verifierBytes.Length < 32 Then
            Array.Resize(verifierBytes, 32)
        End If
        
        Return verifierBytes
    End Function
End Class

关键修复说明 #

• 用户名强制大写：按照数据库规则将用户名转为大写后存储，确保与游戏端验证逻辑一致。
• 修正SQL参数映射：将salt字段与@salt参数正确绑定，彻底移除明文密码存储逻辑，符合SRP6的安全设计。
• BigInteger符号位处理：转换字节数组时添加额外0字节，避免BigInteger将最高位识别为符号位导致计算错误；同时保证最终verifier为32字节大端格式，匹配AzerothCore的存储规则。

内容的提问来源于stack exchange，提问作者Evolution-Team