Method Name:
shared_ciphers
Method Signature:
shared_ciphers()
Parameters:
None
Return Value:
- A list of tuples of ciphers, their TLS (also still called as SSL) protocol version, number of secret bits used.
- None if invoked before the SSL handshake.
Overview:
- The method shared_ciphers() returns a list of tuples containing the ciphers, the TLS protocol version and the number of secret bits shared with the peer.
- It does not make sense to call this method on a server socket before or after connections are accepted.
- However, this method works and retrieves the list of ciphers shared with the peer in the following scenarios:
- A client socket connecting to a server. The method returns the list of tuples containing cipher information After the SSL handshake
- A server creating a client socket for a request from client.
Example:
|
# Example Python program that gets the cipher information # used in a secure communication through SSLScoket import socket import ssl import platform
# SSL context cx = ssl.SSLContext(); cx.verify_mode = ssl.CERT_REQUIRED;
# Check for OS X platform if platform.system().lower() == 'darwin': import certifi import os
# Load the CA certificates used for validating the peer's certificate cx.load_verify_locations( cafile=os.path.relpath(certifi.where()), capath=None, cadata=None);
# Make a secure socket to connect to the server s = socket.socket(); ss = cx.wrap_socket(s);
# Connect to the server ss.connect(("example.com", 443)); shared_ciphers = ss.shared_ciphers(); print("List of shared ciphers :"); print(shared_ciphers); |
Output:
|
List of shared ciphers : [('TLS_AES_256_GCM_SHA384', 'TLSv1.3', 256), ('TLS_CHACHA20_POLY1305_SHA256', 'TLSv1.3', 256), ('TLS_AES_128_GCM_SHA256', 'TLSv1.3', 128), ('ECDHE-ECDSA-AES256-GCM-SHA384', 'TLSv1.2', 256), ('ECDHE-RSA-AES256-GCM-SHA384', 'TLSv1.2', 256), ('DHE-RSA-AES256-GCM-SHA384', 'TLSv1.2', 256), ('ECDHE-ECDSA-CHACHA20-POLY1305', 'TLSv1.2', 256), ('ECDHE-RSA-CHACHA20-POLY1305', 'TLSv1.2', 256), ('DHE-RSA-CHACHA20-POLY1305', 'TLSv1.2', 256), ('ECDHE-ECDSA-AES128-GCM-SHA256', 'TLSv1.2', 128), ('ECDHE-RSA-AES128-GCM-SHA256', 'TLSv1.2', 128), ('DHE-RSA-AES128-GCM-SHA256', 'TLSv1.2', 128), ('ECDHE-ECDSA-AES256-SHA384', 'TLSv1.2', 256), ('ECDHE-RSA-AES256-SHA384', 'TLSv1.2', 256), ('DHE-RSA-AES256-SHA256', 'TLSv1.2', 256), ('ECDHE-ECDSA-AES128-SHA256', 'TLSv1.2', 128), ('ECDHE-RSA-AES128-SHA256', 'TLSv1.2', 128), ('DHE-RSA-AES128-SHA256', 'TLSv1.2', 128), ('ECDHE-ECDSA-AES256-SHA', 'TLSv1.0', 256), ('ECDHE-RSA-AES256-SHA', 'TLSv1.0', 256), ('DHE-RSA-AES256-SHA', 'SSLv3', 256), ('ECDHE-ECDSA-AES128-SHA', 'TLSv1.0', 128), ('ECDHE-RSA-AES128-SHA', 'TLSv1.0', 128), ('DHE-RSA-AES128-SHA', 'SSLv3', 128), ('AES256-GCM-SHA384', 'TLSv1.2', 256), ('AES128-GCM-SHA256', 'TLSv1.2', 128), ('AES256-SHA256', 'TLSv1.2', 256), ('AES128-SHA256', 'TLSv1.2', 128), ('AES256-SHA', 'SSLv3', 256), ('AES128-SHA', 'SSLv3', 128)] |