Windows客户端开发--通过CREDENTIAL保存用户名和密码

向右看齐 2022-07-14 12:11 343阅读 0赞

做windows客户端，尤其是c/s开发，几乎都要接触到用户的登录。需要用户名和密码，那么我们往往要对用户名和密码就行保存。

**方案1：写入ini配置文件**  
用过配置文件保存用户名和密码，密码肯定是不能实明文了，需要采用一定的加密算法。  
但是，这是最大的麻烦，就是很容易被破解，反加密，得到用户的密码。  
如何读取ini文件，请看：[http://blog.csdn.net/wangshubo1989/article/details/47255823][http_blog.csdn.net_wangshubo1989_article_details_47255823]

**方案2：写入数据口**  
可以通过写入数据库的方法，比如写入sqlite。  
弊端和写入ini大差不差，就是容易被破解。

std::string last_name;
      bool success = accounts_tb_->Get(kLastUserNameSqlKey, &last_name);
      if (success) 
      {
        if (!last_name.empty()) {
          return last_team_from_cache;
        }
      }

**方案3：qt中的QSettings**  
在qt中，我们可以使用QSettings来保存用户名和密码：

const static QString SETTING_ACCOUNT_ID = "account_id";
    QSettings *settings = new QSettings();
    settings->setValue(SETTING_ACCOUNT_ID, id);
    
    QString id = settings->value(SETTING_ACCOUNT_ID, "").toString();

**方案4：windows系统上的PCREDENTIALW**

文件夹：  
WinCred.h

PCREDENTIALW介绍：  
The CREDENTIAL structure contains an individual credential.  
原型：

typedef struct _CREDENTIAL {
      DWORD                 Flags;
      DWORD                 Type;
      LPTSTR                TargetName;
      LPTSTR                Comment;
      FILETIME              LastWritten;
      DWORD                 CredentialBlobSize;
      LPBYTE                CredentialBlob;
      DWORD                 Persist;
      DWORD                 AttributeCount;
      PCREDENTIAL_ATTRIBUTE Attributes;
      LPTSTR                TargetAlias;
      LPTSTR                UserName;
    } CREDENTIAL, *PCREDENTIAL;

我们注意关注UserName和CredentialBlob：  
**CredentialBlob**  
Secret data for the credential. The CredentialBlob member can be both read and written.

If the Type member is CRED\_TYPE\_DOMAIN\_PASSWORD, this member contains the plaintext Unicode password for UserName. The CredentialBlob and CredentialBlobSize members do not include a trailing zero character. Also, for CRED\_TYPE\_DOMAIN\_PASSWORD, this member can only be read by the authentication packages.  
If the Type member is CRED\_TYPE\_DOMAIN\_CERTIFICATE, this member contains the clear test Unicode PIN for UserName. The CredentialBlob and CredentialBlobSize members do not include a trailing zero character. Also, this member can only be read by the authentication packages.  
If the Type member is CRED\_TYPE\_GENERIC, this member is defined by the application.  
Credentials are expected to be portable. Applications should ensure that the data in CredentialBlob is portable. The application defines the byte-endian and alignment of the data in CredentialBlob.

**UserName**  
The user name of the account used to connect to TargetName.  
If the credential Type is CRED\_TYPE\_DOMAIN\_PASSWORD, this member can be either a DomainName\\UserName or a UPN.  
If the credential Type is CRED\_TYPE\_DOMAIN\_CERTIFICATE, this member must be a marshaled certificate reference created by calling CredMarshalCredential with a CertCredential.  
If the credential Type is CRED\_TYPE\_GENERIC, this member can be non-NULL, but the credential manager ignores the member.  
This member cannot be longer than CRED\_MAX\_USERNAME\_LENGTH (513) characters.

更多的资料去看看msdn:  
[https://msdn.microsoft.com/en-us/library/windows/desktop/aa374788(v=vs.85).aspx][https_msdn.microsoft.com_en-us_library_windows_desktop_aa374788_v_vs.85_.aspx]

**CredWrite函数**  
作用：  
The CredWrite function creates a new credential or modifies an existing credential in the user’s credential set.  
原型：

BOOL CredWrite(
      _In_ PCREDENTIAL Credential,
      _In_ DWORD       Flags
    );

**CredRead函数**  
作用：  
The CredRead function reads a credential from the user’s credential set.  
原型：

BOOL CredRead(
      _In_  LPCTSTR     TargetName,
      _In_  DWORD       Type,
      _In_  DWORD       Flags,
      _Out_ PCREDENTIAL *Credential
    );

**保存用户名和密码**

bool SaveAccount(const std::string& username, const std::string& password) 
    {
        char password_chars[255] = { 0 };
        wchar_t username_wstrs[255] = { 0 };
        wchar_t target_name_wstrs[1024] = { 0 };
    
        // password
        strcpy(password_chars, password.c_str());
        DWORD cbCreds = 1 + strlen(password_chars);
    
        // username
        std::wstring username_wstr = nbase::UTF8ToUTF16(username);
        wcscpy(username_wstrs, username_wstr.c_str());
    
        // target name
        std::wstring target_name_wstr = L"MyApp";
        wcscpy(target_name_wstrs, target_name_wstr.c_str());
    
        CREDENTIALW cred = { 0 };
        cred.Type = CRED_TYPE_GENERIC;
        cred.TargetName = target_name_wstrs;
        cred.CredentialBlobSize = cbCreds;
        cred.CredentialBlob = (LPBYTE)password_chars;
        cred.Persist = CRED_PERSIST_LOCAL_MACHINE;
        cred.UserName = username_wstrs;
    
        return ::CredWriteW(&cred, 0);
    }

**读取用户名和密码**

bool GetAccount(std::string& username, std::string& password)
    {
        wchar_t username_wstrs[255] = { 0 };
        wchar_t target_name_wstrs[1024] = { 0 };
    
        // target name
        std::wstring target_name_wstr = L"MyApp";
    
        PCREDENTIALW pcred;
    
        BOOL success = false;
        do {
            success = ::CredReadW(target_name_wstr.c_str(), CRED_TYPE_GENERIC, 0, &pcred);
            if (!success)
            {
                break;
            }
            username = nbase::UTF16ToUTF8(pcred->UserName);
    
            std::string pwd((char*)pcred->CredentialBlob, pcred->CredentialBlobSize);
            password = pwd;
            ::CredFree(pcred);
            return true;
        } while (0);
    
        return false;
    }

[http_blog.csdn.net_wangshubo1989_article_details_47255823]: http://blog.csdn.net/wangshubo1989/article/details/47255823
[https_msdn.microsoft.com_en-us_library_windows_desktop_aa374788_v_vs.85_.aspx]: https://msdn.microsoft.com/en-us/library/windows/desktop/aa374788%28v=vs.85%29.aspx