3proxy SSL/TLS Plugin

This plugin can be used to transparently decrypt SSL/TLS data, provide TLS encryption for proxy traffic, and authenticate using client certificates.

For transparent certificate spoofing (MITM):

ssl_mitm - spoof certificates for services started below. Usage without ssl_client_verify is insecure.
ssl_nomitm - do not spoof certificates for services started below

To protect traffic to the server (https:// proxy):

ssl_serv (or ssl_server) - require TLS connection from clients for services below
ssl_noserv (or ssl_noserver) - do not require TLS connection from clients for services below

To use TLS for upstream connections:

ssl_cli (or ssl_client) - establish TLS connection to upstream server for services below
ssl_nocli (or ssl_noclient) - do not establish TLS connection to upstream server for services below

Parameters:

ssl_server_cert /path/to/cert - Server certificate (should not be self-signed and must contain an Alternative Name) for ssl_serv
ssl_server_key /path/to/key - Server certificate key for ssl_server_cert or generated MITM certificate
ssl_client_cert /path/to/cert - Client certificate for authentication on upstream server (used with ssl_cli)
ssl_client_key /path/to/key - Client certificate key for ssl_client_cert
ssl_client_ciphersuites ciphersuites_list - TLS client ciphers for TLS 1.3, e.g., ssl_client_ciphersuites TLS_AES_128_GCM_SHA256
ssl_server_ciphersuites ciphersuites_list - TLS server ciphers for TLS 1.3
ssl_client_cipher_list ciphers_list - TLS client ciphers for TLS 1.2 and below, e.g., ssl_client_cipher_list ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384:DHE-RSA-CHACHA20-POLY1305
ssl_server_cipher_list ciphers_list - TLS server ciphers for TLS 1.2 and below
ssl_client_min_proto_version tls_version - TLS client minimum TLS version (e.g., TLSv1.2)
ssl_server_min_proto_version tls_version - TLS server minimum TLS version (e.g., TLSv1.2)
ssl_client_max_proto_version tls_version - TLS client maximum TLS version (e.g., TLSv1.2)
ssl_server_max_proto_version tls_version - TLS server maximum TLS version (e.g., TLSv1.2)
ssl_client_verify - verify the certificate for the upstream server in TLS client functionality (used with ssl_mitm or ssl_cli)
ssl_client_no_verify - do not verify the certificate for the upstream server in TLS client functionality (default)
ssl_server_verify - require client certificate authentication (mTLS) for ssl_serv
ssl_server_no_verify - do not require client certificate (default)
ssl_server_ca_file /path/to/cafile - CA certificate file for MITM
ssl_server_ca_key /path/to/cakey - key for ssl_server_ca_file MITM CA
ssl_server_ca_dir /path/to/cadir - CA directory for ssl_server_verify
ssl_server_ca_store /path/to/castore - CA store for ssl_server_verify (OpenSSL 3.0+)
ssl_client_ca_file /path/to/cafile - CA file for ssl_client_verify
ssl_client_ca_dir /path/to/cadir - CA directory for ssl_client_verify
ssl_client_ca_store /path/to/castore - CA store for ssl_client_verify (OpenSSL 3.0+)
ssl_client_sni hostname - SNI hostname to send to upstream server (overrides the requested hostname)
ssl_client_alpn protocol1 protocol2 ... - ALPN protocols to negotiate with upstream server (e.g., ssl_client_alpn h2 http/1.1)
ssl_client_mode mode - when to establish TLS connection: 0 - on connect (default), 1 - after authentication, 2 - before data
ssl_certcache /path/to/cache/ - location for the generated MITM certificates cache, optional if ssl_server_ca_file / ssl_server_ca_key are configured. The cache may contain 3 files: 3proxy.pem - public self-signed certificates (used if ssl_server_ca_file is not configured), 3proxy.key - key for public certificates, used if ssl_server_ca_key is not configured, server.key - this key is used if ssl_server_key is not configured to generate spoofed certificates. If server.key is absent, 3proxy.key is used to generate certificates. Generated certificates are placed in the same path.

MITM example:

plugin /path/to/SSLPlugin.so ssl_plugin
ssl_server_ca_file /path/to/cafile
ssl_server_ca_key /path/to/cakey
ssl_mitm
proxy -p3128
ssl_nomitm
proxy -p3129

MITM's traffic with a spoofed certificate for the port 3128 proxy.

https:// proxy example:

plugin /path/to/SSLPlugin.so ssl_plugin
ssl_server_cert path_to_cert
ssl_server_key path_to_key
ssl_serv
proxy -p33128
ssl_noserv
proxy -p3128

Creates an https:// proxy on port 33128 and an http:// proxy on port 3128

TLS client example (connect to upstream via TLS):

plugin /path/to/SSLPlugin.so ssl_plugin
ssl_client_cert /path/to/client.crt
ssl_client_key /path/to/client.key
ssl_client_verify
ssl_client_ca_file /path/to/ca.crt
ssl_cli
proxy -p3128

Creates an HTTP proxy that connects to upstream servers via TLS with client certificate authentication.

mTLS example (require client certificate):

plugin /path/to/SSLPlugin.so ssl_plugin
ssl_server_cert /path/to/server.crt
ssl_server_key /path/to/server.key
ssl_server_ca_file /path/to/ca.crt
ssl_server_verify
ssl_serv
proxy -p3128