Webサイトをスキャンして、開いているポートを確認しようとしています。ループを使用しているときにこのロジックが機能しない理由がわかりません

すべての接続に対して、新しいソケットを使用する必要があります

def scanner(ip, port):
    s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    s.settimeout(10)

    if s.connect_ex((ip, port)):
        print(port, "is closed.")
    else:
        print(port, "is open.")

    s.close()

編集： Stackoverflowでこの答えも見つけました：複数の接続に同じソケットを使用できますか？

他の小さな変更を加えた完全なコード

import socket

# --- functions ---

def scanner(ip, port):
    s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    s.settimeout(10)

    if s.connect_ex((ip, port)):
        print(port, "is closed.")
    else:
        print(port, "is open.")

    s.close()

# --- main ---

port_list = {
    1: "TCP Port Service Multiplexer (TCPMUX)",
    5: "Remote Job Entry (RJE)",
    7: "ECHO",
    18: "Message Send Protocol (MSP)",
    20: "FTP -- Data",
    21: "FTP -- Control",
    22: "SSH Remote Login Protocol",
    23: "Telnet",
    25: "Simple Mail Transfer Protocol (SMTP)",
    29: "MSG ICP",
    37: "Time",
    42: "Host Name Server (Nameserv)",
    43: "WhoIs",
    49: "Login Host Protocol (Login)",
    53: "Domain Name System (DNS)",
    69: "Trivial File Transfer Protocol (TFTP)",
    70: "Gopher Services",
    79: "Finger",
    80: "HTTP",
    103: "X.400 Standard",
    108: "SNA Gateway Access Server",
    109: "POP2",
    110: "POP3",
    115: "Simple File Transfer Protocol (SFTP)",
    118: "SQL Services",
    119: "Newsgroup (NNTP)",
    137: "NetBIOS Name Service",
    139: "NetBIOS Datagram Service",
    143: "Interim Mail Access Protocol (IMAP)",
    150: "NetBIOS Session Service",
    156: "SQL Server",
    161: "SNMP",
    179: "Border Gateway Protocol (BGP)",
    190: "Gateway Access Control Protocol (GACP)",
    194: "Internet Relay Chat (IRC)",
    197: "Directory Location Service (DLS)",
    389: "Lightweight Directory Access Protocol (LDAP)",
    396: "Novell Netware over IP",
    443: "HTTPS",
    444: "Simple Network Paging Protocol (SNPP)",
    445: "Microsoft-DS",
    458: "Apple QuickTime",
    546: "DHCP Client",
    547: "DHCP Server",
    563: "SNEWS",
    569: "MSN",
    1080: "Socks",
}

ip = input("IP Address: ")

print("List of commonly used ports: ")
for port, name  in port_list.items():
    print(port, name)

for port in port_list:
    scanner(ip, port)

ところで： Linuxでは、に短い名前の一般的なポートがあります/etc/services。Windowsでは、似たようなものになっているはずservicesです。おそらく、名前のファイルもあります。

このファイルの一部：

tcpmux      1/tcp               # TCP port service multiplexer
echo        7/tcp
echo        7/udp
discard     9/tcp       sink null
discard     9/udp       sink null
systat      11/tcp      users
daytime     13/tcp
daytime     13/udp
netstat     15/tcp
qotd        17/tcp      quote
msp         18/tcp              # message send protocol
msp         18/udp
chargen     19/tcp      ttytst source
chargen     19/udp      ttytst source
ftp-data    20/tcp
ftp         21/tcp
fsp         21/udp      fspd
ssh         22/tcp              # SSH Remote Login Protocol