支付宝移动支付，服务端对异步通知信息验签的时候验签失败
支付宝异步通知数据形式如下，
$arr=array ( 'discount' => '0.00', 'payment_type' => '1', 'subject' => '测试02', 'trade_no' => '2016031.............2958619', 'buyer_email' => '18776152065', 'gmt_create' => '2016-03-14 17:04:52', 'notify_type' => 'trade_status_sync', 'quantity' => '1', 'out_trade_no' => '16031238100064254059', 'seller_id' => '2099122451677261', 'notify_time' => '2016-03-14 17:04:53', 'body' => '测试02', 'trade_status' => 'TRADE_SUCCESS', 'is_total_fee_adjust' => 'N', 'total_fee' => '0.01', 'gmt_payment' => '2016-03-14 17:04:52', 'seller_email' => '[email protected]', 'price' => '0.01', 'buyer_id' => '2065912804441725', 'notify_id' => '2cf4b6638.............c176e3f3lk2', 'use_coupon' => 'N', 'sign_type' => 'RSA', 'sign' => 'Q3uCDyyCs/nODpHaUeCb1HqGINlQ3AxOr40MUN.............Br40MU=', )
对数组按KEY首字母排序
ksort($arr);
按官方文档做法，排除掉sign_type,sign然后拼成下面形式的待签名支付串 $SemiFinishedSign
body=Hello&buyer_email=13788888888&buyer_id=2088002007013600 ................................................................................. trade_no=2014040311001004361525&trade_status=TRADE_FINISHED&use_coupon=N
执行下面代码验签！
$pukey=file_get_contents('alipay_public_key.pem');
$publickey=openssl_pkey_get_public($pukey);
$verify=(bool)openssl_verify($SemiFinishedSign, base64_decode($arr['sign']), $publickey);
echo $verify?'验签成功':'验签失败';
用于支付的公私钥都没有问题，对任意字符，openssl_sign();openssl_verify();都能通过
但是验签总是失败
--------------------------更新 2016-03-15-----------------------------------------
已解决，文档中说，验签用的是支付宝公钥，并不是RSA公钥，申请接口的人没有给我支付宝公钥，我一直以为用RSA公钥，我用错了，上传公钥，然后复制支付宝公钥下来用于验证签名。
转载：https://segmentfault.com/q/1010000004607880
参考：
https://doc.open.alipay.com/doc2/detail?treeId=59&articleId=103927&docType=1
https://doc.open.alipay.com/doc2/detail.htm?spm=a219a.7629140.0.0.F1IOBD&treeId=58&articleId=103596&docType=1