我们用openresty做网关，有提供单向https（证书配在ELB）和双向TLS的访问模式，会有来自手机Android和iOS APP的访问，还有一些非手机Android设备的访问。
最近没有更改/更新过代码，突然持续报错（日志如下），证书感觉没有问题，单向https和双向TLS的访问均能正常处理，没有搜到有效的解决方式，担心受到攻击，求大神解惑。
019/05/21 20:07:20 [crit] 14298#14298: *556855245 SSL_do_handshake() failed (SSL: error:04091068:rsa routines:int_rsa_verify:bad signature error:1417B07B:SSL routines:tls_process_cert_verify:bad signature) while SSL handshaking, client: 10.126.195.131, server: 0.0.0.0:443
2019/05/21 20:07:20 [crit] 14301#14301: *556855244 SSL_do_handshake() failed (SSL: error:04091068:rsa routines:int_rsa_verify:bad signature error:1417B07B:SSL routines:tls_process_cert_verify:bad signature) while SSL handshaking, client: 10.126.194.173, server: 0.0.0.0:443
2019/05/21 20:07:20 [crit] 14298#14298: *556855241 SSL_do_handshake() failed (SSL: error:04091068:rsa routines:int_rsa_verify:bad signature error:1417B07B:SSL routines:tls_process_cert_verify:bad signature) while SSL handshaking, client: 10.126.195.131, server: 0.0.0.0:443
2019/05/21 20:07:20 [crit] 14298#14298: *556855274 SSL_do_handshake() failed (SSL: error:1417D102:SSL routines:tls_process_client_hello:unsupported protocol) while SSL handshaking, client: 10.126.194.173, server: 0.0.0.0:443
2019/05/21 20:07:20 [crit] 14298#14298: *556855272 SSL_do_handshake() failed (SSL: error:1417D102:SSL routines:tls_process_client_hello:unsupported protocol) while SSL handshaking, client: 10.126.195.131, server: 0.0.0.0:443
2019/05/21 20:07:20 [crit] 14298#14298: *556855273 SSL_do_handshake() failed (SSL: error:1417D102:SSL routines:tls_process_client_hello:unsupported protocol) while SSL handshaking, client: 10.126.194.173, server: 0.0.0.0:443
版本信息如下：
openresty/1.13.6.2
nginx/1.12.1
OpenSSL 1.0.2k-fips
