securityutils.cpp

一个WinCE6。0下的IP phone的源代码

//
// Copyright (c) Microsoft Corporation.  All rights reserved.
//
//
// Use of this sample source code is subject to the terms of the Microsoft
// license agreement under which you licensed this sample source code. If
// you did not accept the terms of the license agreement, you are not
// authorized to use this sample source code. For the terms of the license,
// please see the license agreement between you and Microsoft or, if applicable,
// see the LICENSE.RTF on your install media or the root of your tools installation.
// THE SAMPLE SOURCE CODE IS PROVIDED "AS IS", WITH NO WARRANTIES.
//
#include "securityutils.h"
#include "Cred.h"
#include "commonmacros.h"

#define MAX_USERNAME 15
#define MAX_DOMAIN   12

/*------------------------------------------------------------------------------
    GetPlaintextCredentials
    
    Get the credentials from CredMan
------------------------------------------------------------------------------*/
HRESULT GetPlaintextCredentials(
    WCHAR *wszDomainBuffer, 
    UINT    cchDomainBuffer,
    WCHAR *wszUserBuffer, 
    UINT    cchUserBuffer,
    WCHAR *wszPasswordBuffer, 
    UINT cchPasswordBuffer
    )
{
    CRED   *pCredPassword   = NULL;
    HRESULT hr              = S_OK;
    WCHAR  *pwchDomainUserNameSeparator = NULL;

    if (
        wszDomainBuffer   == NULL ||
        wszUserBuffer     == NULL ||
        wszPasswordBuffer == NULL
        )
    {
        return E_POINTER;
    }

    if (
        cchDomainBuffer == 0 ||
        cchUserBuffer   == 0 ||
        cchPasswordBuffer == 0
       )
    {
        return E_INVALIDARG;
    }
    
    //Read the credentials
    DWORD dwRes = CredRead(
        L"",
        1,
        CRED_TYPE_PLAINTEXT_PASSWORD,
        CRED_FLAG_NO_DEFAULT | CRED_FLAG_NO_IMPLICIT_DEFAULT,
        &pCredPassword
        );

    if (dwRes != ERROR_SUCCESS)
    {
        hr = HRESULT_FROM_WIN32(GetLastError());
        goto exit;
    }

    PREFAST_ASSERT(pCredPassword != NULL);

    //Fill the password buffer
    if (pCredPassword->pBlob != NULL)
    {
        StringCchCopy(wszPasswordBuffer, cchPasswordBuffer, (WCHAR*)pCredPassword->pBlob);
    }
    else
    {
        //if NULL password we fail
        hr = E_FAIL;
        goto exit;
    }
    
    //Parse the domainusername
    PREFAST_ASSERT(pCredPassword->wszUser);
    pwchDomainUserNameSeparator = wcschr(pCredPassword->wszUser, L'\\');
    
    if (pwchDomainUserNameSeparator != NULL)
    {
        *pwchDomainUserNameSeparator = 0;
        pwchDomainUserNameSeparator++;
        StringCchCopy(wszUserBuffer, cchUserBuffer, pwchDomainUserNameSeparator);
    }
    
    StringCchCopy(wszDomainBuffer, cchDomainBuffer, pCredPassword->wszUser);

exit:

    if (pCredPassword != NULL)
    {
        CredFree((BYTE*)pCredPassword);
    }
    
    return hr;
}

/*------------------------------------------------------------------------------
    WriteCredentials
    
    Writes the credentials to CredMan
------------------------------------------------------------------------------*/
HRESULT WriteCredentials(
    const WCHAR *c_wszDomain,
    const WCHAR *c_wszUsername,
    const WCHAR *c_wszPassword
    )
{
    HRESULT hr = S_OK;
    CRED credPassword = {0};
    INT cchDomain     = 0,
        cchUser       = 0,
        cchPass       = 0;


    if (
        c_wszDomain   == NULL ||
        c_wszUsername == NULL ||
        c_wszPassword == NULL
        )
    {
        hr = E_POINTER;
        goto exit;
    }
    
    cchDomain     = wcslen(c_wszDomain);
    cchUser       = wcslen(c_wszUsername);
    cchPass       = wcslen(c_wszPassword);

    DWORD dwResult    = S_OK;
    WCHAR wszDomainUsername[MAX_PATH] = L"";

    if ((cchDomain + cchUser) >= (ARRAYSIZE(wszDomainUsername)-1))
    {
        hr = E_INVALIDARG;
        goto exit;
    }
    
    StringCchCopy (wszDomainUsername, _countof(wszDomainUsername), c_wszDomain);
    wszDomainUsername[cchDomain] = L'\\';
    StringCchCopy(wszDomainUsername + cchDomain + 1, _countof(wszDomainUsername) - cchDomain - 1, c_wszUsername);

    //first write the credential as a domain password that is keyed off domain name
    credPassword.dwVersion   = CRED_VER_1;
    credPassword.dwType      = CRED_TYPE_PLAINTEXT_PASSWORD;  //we'll update the domain password later
    credPassword.wszUser     = wszDomainUsername;           
    credPassword.dwUserLen   = cchDomain + cchUser + 1 + 1;
    credPassword.wszTarget   = L"";                
    credPassword.dwTargetLen = 1;
    credPassword.pBlob       = (BYTE*)c_wszPassword;
    credPassword.dwBlobSize  = (cchPass + 1) * sizeof(WCHAR);
    credPassword.dwFlags     = CRED_FLAG_PERSIST | CRED_FLAG_TRUSTED;

    dwResult = CredWrite(
        &credPassword,
        0
        );

    if (dwResult != ERROR_SUCCESS)
    {
        ASSERT(FALSE);
        hr = HRESULT_FROM_WIN32(GetLastError());
        goto exit;
    }

    //now write the credential as a domain password (Kerb and NTLM)
    credPassword.dwType      = CRED_TYPE_DOMAIN_PASSWORD;
    credPassword.dwFlags    &= ~CRED_FLAG_TRUSTED; //allow untrusted apps to use cached creds
    
    dwResult = CredWrite(
        &credPassword,
        0
        );

    if (dwResult != ERROR_SUCCESS)
    {
        ASSERT(FALSE);
        hr = HRESULT_FROM_WIN32(GetLastError());
        goto exit;
    }

exit:
    return hr;
}

//Helper function
HRESULT GetLoggedInUserInformation(
    WCHAR *wszOutBuf, 
    UINT    cchBuf, 
    UINT    fItemToGet
    )
{
    CRED   *pCredDomain = NULL;
    HRESULT hr          = S_OK;
    DWORD   dwRes       = 0;
    WCHAR  *pwchDomain  = NULL, 
           *pwchCopy    = NULL;
    UINT    cchCopy     = 0;
    
    if (! wszOutBuf)
    {
        ASSERT(FALSE);
        return E_POINTER;
    }

    dwRes = CredRead(
        L"",
        1,
        CRED_TYPE_DOMAIN_PASSWORD,
        CRED_FLAG_NO_DEFAULT | CRED_FLAG_NO_IMPLICIT_DEFAULT,
        &pCredDomain
        );
    if (dwRes != ERROR_SUCCESS)
    {
        hr = HRESULT_FROM_WIN32(GetLastError());
        goto exit;
    }

    if (! pCredDomain || !pCredDomain->wszUser)
    {
        ASSERT(FALSE);
        hr = E_FAIL;
        goto exit;
    }
    
    pwchDomain = wcschr(pCredDomain->wszUser, L'\\');
    if (! pwchDomain)
    {
        DEBUGMSG(1, (L"We found default domain cred's but NO domain"));
        ASSERT(FALSE);
        hr = E_FAIL;
    }

    switch (fItemToGet)
    {
    case CRED_ITEM_DOMAINUSERNAME:
        pwchCopy = pCredDomain->wszUser;
        cchCopy  = cchBuf;
        break;
        
    case CRED_ITEM_DOMAIN:
        pwchCopy = pCredDomain->wszUser;
        cchCopy  = pwchDomain - pCredDomain->wszUser;
        break;
        
    case CRED_ITEM_USERNAME:
        pwchCopy = pwchDomain + 1;
        cchCopy  = cchBuf;
        break;

    default:
        ASSERT(FALSE);
        hr = E_INVALIDARG;
        goto exit;
    }

    StringCchCopy(wszOutBuf, min(cchBuf, cchCopy), pwchCopy);

exit:    
    if (pCredDomain)
    {
        CredFree((BYTE*)pCredDomain);        
    }

    return hr;
}

BOOL PhoneHasCredentials()
{
    WCHAR wszBuf[3] = L"";
    HRESULT hr      = S_OK;

    hr = GetLoggedInUserInformation(
        wszBuf, 
        ARRAYSIZE(wszBuf),
        CRED_ITEM_DOMAINUSERNAME
        );

    return (SUCCEEDED(hr) && wszBuf[0]);
}