Paypal订阅IPN返回无效

正如标题所述，我对Paypal有问题，IPN返回已验证订阅支付方式。到目前为止，对于我所做的每一个订阅IPN，它都返回了INVALID和数据。问题是，对于相同的代码，例如，将按钮从_xclick-subscriptions更改为_donations会给我一个经过验证的结果。

我一直在寻找一段时间来解决我的问题，但一直找不到。事情是这样的——我创建了一个订阅按钮，将用户引导到贝宝（在本例中为沙盒），然后在那里付款，付款后他们可以选择返回网站。这是按钮的代码。

<form action="https://www.sandbox.paypal.com/cgi-bin/webscr" method="post">
<input type="image" src="https://www.paypal.com/en_US/i/btn/x-click-but20.gif" border="0" name="submit" alt="Make payments with PayPal - it's fast, free and secure!">
<input type="hidden" name="cmd" value="_xclick-subscriptions">
<input type="hidden" name="business" value="mail@url.com"> 
<input type="hidden" name="item_name" value="Monthly Sub">
<input type="hidden" name="no_note" value="1">
<input type="hidden" name="currency_code" value="USD">
<input type="hidden" name="a3" value="10.00"> 
<input type="hidden" name="p3" value="1"> 
<input type="hidden" name="t3" value="M"> 
<input type="hidden" name="src" value="1"> 
<input type="hidden" name="sra" value="1">
<input type="hidden" name="rm" value="2">
<input type="hidden" name="return" value="http://url.com/thanks.php">
</form>

由于这对我来说是一个不错的问题，我已经将按钮分解为具有几乎基本的必需值，直到我能够真正让它返回验证而不是无效。以下是我作为IPN侦听器使用的代码。

define("DEBUG", 1);
define("USE_SANDBOX", 1);
define("LOG_FILE", "./ipn.log");
// Read POST data
// reading posted data directly from $_POST causes serialization
// issues with array data in POST. Reading raw POST data from input stream instead.
$raw_post_data = file_get_contents('php://input');
$raw_post_array = explode('&', $raw_post_data);
$myPost = array();
foreach ($raw_post_array as $keyval) {
    $keyval = explode ('=', $keyval);
    if (count($keyval) == 2)
        $myPost[$keyval[0]] = urldecode($keyval[1]);
}
// read the post from PayPal system and add 'cmd'
$req = 'cmd=_notify-validate';
if(function_exists('get_magic_quotes_gpc')) {
    $get_magic_quotes_exists = true;
}
foreach ($myPost as $key => $value) {
    if($get_magic_quotes_exists == true && get_magic_quotes_gpc() == 1) {
        $value = urlencode(stripslashes($value));
    } else {
        $value = urlencode($value);
    }
    $req .= "&$key=$value";
}
// Post IPN data back to PayPal to validate the IPN data is genuine
// Without this step anyone can fake IPN data
if(USE_SANDBOX == true) {
    $paypal_url = "https://www.sandbox.paypal.com/cgi-bin/webscr";
} else {
    $paypal_url = "https://www.paypal.com/cgi-bin/webscr";
}
$ch = curl_init($paypal_url);
if ($ch == FALSE) {
    return FALSE;
}
curl_setopt($ch, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_1_1);
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_RETURNTRANSFER,1);
curl_setopt($ch, CURLOPT_POSTFIELDS, $req);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 1);
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 2);
curl_setopt($ch, CURLOPT_FORBID_REUSE, 1);
if(DEBUG == true) {
    curl_setopt($ch, CURLOPT_HEADER, 1);
    curl_setopt($ch, CURLINFO_HEADER_OUT, 1);
}
// Set TCP timeout to 30 seconds
curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 30);
curl_setopt($ch, CURLOPT_HTTPHEADER, array('Connection: Close'));
$res = curl_exec($ch);
if (curl_errno($ch) != 0) // cURL error
    {
    if(DEBUG == true) { 
        error_log(date('[Y-m-d H:i e] '). "Can't connect to PayPal to validate IPN message: " . curl_error($ch) . PHP_EOL, 3, LOG_FILE);
    }
    curl_close($ch);
    exit;
} else {
        // Log the entire HTTP response if debug is switched on.
        if(DEBUG == true) {
            error_log(date('[Y-m-d H:i e] '). "HTTP request of validation request:". curl_getinfo($ch, CURLINFO_HEADER_OUT) ." for IPN payload: $req" . PHP_EOL, 3, LOG_FILE);
            error_log(date('[Y-m-d H:i e] '). "HTTP response of validation request: $res" . PHP_EOL, 3, LOG_FILE);
            // Split response headers and payload
            list($headers, $res) = explode("'r'n'r'n", $res, 2);
        }
        curl_close($ch);
}
// Inspect IPN validation result and act accordingly
if (strcmp ($res, "VERIFIED") == 0) {
    if(DEBUG == true) {
        error_log(date('[Y-m-d H:i e] '). "Verified IPN: $req ". PHP_EOL, 3, LOG_FILE);
    }
} else if (strcmp ($res, "INVALID") == 0) {
    if(DEBUG == true) {
        error_log(date('[Y-m-d H:i e] '). "Invalid IPN: $req" . PHP_EOL, 3, LOG_FILE);
    }
}

正如我前面所说，_donations的cmd值返回VERIFIED，但_xclick-subscriptions返回INVALID和数据。我在这里有一个返回的数据示例。

cmd=_notify-validate&txn_type=subscr_signup&subscr_id=I-SFYTVAKSSYGK&last_name=lastname&residence_country=US&mc_currency=USD&item_name=Monthly+Sub&business=mail%40url.com&amount3=10.00&recurring=1&address_street=1+Main+St&payer_status=verified&payer_email=name%40email.com&address_status=confirmed&first_name=firstname&receiver_email=mail%40url.com&address_country_code=US&payer_id=SYPW3V3BVWTJW&address_city=San+Jose&reattempt=1&address_state=CA&subscr_date=07%3A33%3A13+Aug+27%2C+2014+PDT&address_zip=95131&charset=windows-1252&period3=1+M&address_country=United+States&mc_amount3=10.00&address_name=firstname+lastname&auth=AwIHoldf-BK2GZqtPhPo0O2g3go74cV9ZOLRYhHTJdKDM5EP0YHuqHLo23RYPfQs-3YDnvhjVf.J3AtydGfvDfA&form_charset=UTF-8

老实说，我不知道从现在开始该去哪里，所以非常感谢任何和所有的帮助！