递归免费3级域名

有趣的DNSliangdong@smzdm.
com域名www.
smzdm.
com.
根域顶级域二级域三级域域名实战-解析域名digwww.
smzdm.
com域名是递归解析的域名服务器实战-递归解析dig@198.
41.
0.
4www.
smzdm.
comdig@192.
12.
94.
30www.
smzdm.
comdig@101.
226.
220.
13www.
smzdm.
comdig@198.
41.
0.
4c4b0af8c607ae831.
vip.
jiasule.
orgdig@199.
19.
57.
1c4b0af8c607ae831.
vip.
jiasule.
orgdig@117.
21.
219.
80c4b0af8c607ae831.
vip.
jiasule.
orgcurl'https://112.
90.
216.
108'-H'Host:www.
smzdm.
com'--insecureDNS架构.
非递归NS.
com非递归NS.
smzdm.
com非递归NS运营商/自建递归NS234电脑1总结客户端没有递归特性/etc/resolv.
conf配置的nameserver必须是递归的根级/顶级服务器是非递归的了解DNS协议包结构查询与应答总结53端口,支持UDP、TCP,操作系统api默认采用udpudp无状态,可以伪造应答造成dns污染实战:PYTHON构造DNS请求1,创建UDPSOCKETimportsocketimportdns.
message,dns.
rrset#UDPsocketsock=socket.
socket(socket.
AF_INET,socket.
SOCK_DGRAM)2,发送DNS请求dns_server=('8.
8.
8.
8',53)domain='www.
google.
com.
com'#DNSrequestrequest=dns.
message.
make_query(domain,'A')sock.
sendto(request.
to_wire(),dns_server)3,接收DNS应答#DNSresponseresponse=sock.
recv(1024)response=dns.
message.
from_wire(response)print(response)4、分析应答id31228opcodeQUERYrcodeNOERRORflagsQRRDRA;QUESTIONwww.
google.
com.
com.
INA;ANSWERwww.
google.
com.
com.
117INA199.
59.
148.
14;AUTHORITY;ADDITIONAL彩蛋:GFW