Ich habe die Aufgabe, einen einfachen Mail-Client zu schreiben und über Sockets eine Verbindung zu einem Google SMTP-Server herzustellen (ohne die SMTP-Lib zu verwenden). Das Ausgeben eines MAIL FROM-Befehls an einen Google SMTP-Server erfordert jedoch SSL oder TLS, und dies ist der Teil, den ich nicht herausfinden kann. Ich versuche, Pythons ssl.wrap_socket () -Methode so zu verwenden ....

# Create socket called clientSocket and establish a TCP connection with mailserver
clientSocket = socket(AF_INET, SOCK_STREAM)
ssl_clientSocket = ssl.wrap_socket(clientSocket) 
ssl_clientSocket.connect((mailserver, port))

... was nicht funktioniert. Ich bin mir ziemlich sicher, dass ich die Parameter ca_certs und ca_reqs einschließen muss, bin mir aber nicht sicher. Und wenn ja, wie erhalte ich diese Zertifikate? Muss ich openssl herunterladen und eines generieren? Hat jemand Erfahrung damit? Hier ist der gesamte Code, um auf der sicheren Seite zu sein.

from socket import *
import ssl

msg = "\r\n I love computer networks!"
endmsg = "\r\n.\r\n"

# Choose a mail server (e.g. Google mail server) and call it mailserver
mailserver = "smtp.gmail.com"
port = 587

# Create socket called clientSocket and establish a TCP connection with mailserver
clientSocket = socket(AF_INET, SOCK_STREAM)
ssl_clientSocket = ssl.wrap_socket(clientSocket) 
ssl_clientSocket.connect((mailserver, port))

recv = ssl_clientSocket.recv(1024)
print
print recv

# If the first three numbers of what we receive from the SMTP server are not
# '220', we have a problem
if recv[:3] != '220':
    print '220 reply not received from server.'

# Send HELO command and print server response.
heloCommand = 'HELO Alice\r\n'
ssl_clientSocket.send(heloCommand)
recv1 = ssl_clientSocket.recv(1024)
print recv1

# If the first three numbers of the response from the server are not
# '250', we have a problem
if recv1[:3] != '250':
    print '250 reply not received from server.'

# Send MAIL FROM command and print server response.
mailFromCommand = 'MAIL From: [email protected]\r\n'
ssl_clientSocket.send(mailFromCommand)
recv2 = ssl_clientSocket.recv(1024)
print recv2

# If the first three numbers of the response from the server are not
# '250', we have a problem
if recv2[:3] != '250':
    print '250 reply not received from server.'

# Send RCPT TO command and print server response.
rcptToCommand = 'RCPT To: [email protected]\r\n'
ssl_clientSocket.send(rcptToCommand)
recv3 = ssl_clientSocket.recv(1024)
print recv3

# If the first three numbers of the response from the server are not
# '250', we have a problem
if recv3[:3] != '250':
    print '250 reply not received from server.'

# Send DATA command and print server response.
dataCommand = 'DATA\r\n'
ssl_clientSocket.send(dataCommand)
recv4 = ssl_clientSocket.recv(1024)
print recv4

# If the first three numbers of the response from the server are not
# '250', we have a problem
if recv4[:3] != '250':
    print '250 reply not received from server.'

# Send message data.
ssl_clientSocket.send(msg)

# Message ends with a single period.
ssl_clientSocket.send(endmsg)

# Send QUIT command and get server response.
quitCommand = 'QUIT\r\n'
ssl_clientSocket.send(quitCommand)
recv5 = ssl_clientSocket.recv(I1024)
print recv5

# If the first three numbers of the response from the server are not
# '250', we have a problem
if recv5[:3] != '221':
    print '221 reply not received from server.'