php - 使用 HTTP_X_SIGNATURE 验证 Coinbase IPN

Question

我已经为比特币交易集成了 Coinbase，除了已经实现的其他安全功能之外，我还想使用他们的签名来验证 IPN 是否真的来自他们。

他们的支持表明“验证 x_signature header 中是否包含正确的签名。包含的签名将使用以下公钥完成:https://www.coinbase.com/coinbase.pub。”

使用 openssl_verify documentation ，我将以下内容放在一起:

function verifyX_SIGNATURE()
{
    // $data and $signature are assumed to contain the data and the signature

    // fetch public key from certificate and ready it
    $fp = fopen("https://www.coinbase.com/coinbase.pub", "r");
    $cert = fread($fp, 8192);
    fclose($fp);

    $pubkeyid = openssl_pkey_get_public($cert);

    // from $_SERVER['HTTP_X_SIGNATURE'] header (data masked)
    $signature = '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';

    // IPN sent in JSON (data masked)
    $data = '{"order":{"id":"BWU44QUL","created_at":"2015-02-11T14:49:41-08:00","status":"completed","event":{"type":"completed"},"total_btc":{"cents":345660.0,"currency_iso":"BTC"},"total_native":{"cents":30.0,"currency_iso":"USD"},"total_payout":{"cents":0.0,"currency_iso":"USD"},"custom":"1089215012665154939","receive_address":"QRwGZSkh3eoj4XTJFk1rZsy74zTouHY5HA","button":{"type":"buy_now","subscription":false,"repeat":null,"name":"30 karma","description":"30 karma @ $0.01 USD each","id":"9bd1d424582687qac22c3037u5axacf1"},"refund_address":"1Fn2ou3rZRStYgtq8v6Taz47drueyQzrF2","transaction":{"id":"54b8441c7dsfbb9b38105022","hash":"ad9d5d6671b6764fc122923fff90a5b7cdb5ec531eb42cd92bda937465b98d76","confirmations":0}}}';

    // state whether signature is okay or not
    $ok = openssl_verify($data, $signature, $pubkeyid);

    if ($ok == 1) {
        echo "good";
    } elseif ($ok == 0) {
        echo "bad";
    } else {
        echo "ugly, error checking signature";
    }
    // free the key from memory
    openssl_free_key($pubkeyid);
}

这不是验证(即打印“错误”)并且他们的 API 库没有函数。我已经屏蔽了数据，但对于我在此过程中做错了什么的任何建议，我将不胜感激。提前谢谢你。

Answer 1

openssl_verify适用于原始二进制字符串，而不是其 base64 表示。在将它传递给 openssl_verify 之前，只需对 $signature 进行 base64_decode，就可以了。

除此之外，第三个参数接受常规 PEM 字符串 key ，因此只需将其直接传递给该方法即可。