ss-tunnel

shadowsocks tools for local port forwarding, C implementation

SYNOPSIS

ss-tunnel [options]

DESCRIPTION

shadowsocks-c is a lightweight and secure socks5 proxy. It is a port of the original shadowsocks created by clowwindy. shadowsocks-c is written in pure C and takes advantage of libuv to achieve both high performance and low resource consumption.

shadowsocks-c consists of five components. ss-tunnel(1) is a tool for local port forwarding. See OPTIONS section for special option needed by ss-tunnel(1). For more information, check out shadowsocks-libev(8).

OPTIONS

Options include all supported platform variants; restrictions are noted below.

-f <pid_file>

Start shadowsocks as a daemon with specific pid file.

-s <server_host>

Set the server's hostname or IP.

-p <server_port>

Set the server's port number.

-l <local_port>

Set the local port number.

-k <password>

Set the password. The server and the client should use the same password.

-t <timeout>

Set the socket timeout in seconds. The default value is 60.

-m <encrypt_method>

Set the cipher. The default is chacha20-ietf-poly1305.

AEAD cipher names from the source (availability depends on the build):

    "aes-128-gcm",
    "aes-192-gcm",
    "aes-256-gcm",
    "2022-blake3-aes-128-gcm",
    "2022-blake3-aes-256-gcm",
    "chacha20-ietf-poly1305",
    "2022-blake3-chacha20-poly1305",
#ifdef FS_HAVE_XCHACHA20IETF
    "xchacha20-ietf-poly1305"
#endif

Legacy stream cipher names recognized by the source (disabled in minimal builds; some require backend support):

    "table",
    "rc4",
    "rc4-md5",
    "aes-128-cfb",
    "aes-192-cfb",
    "aes-256-cfb",
    "aes-128-ctr",
    "aes-192-ctr",
    "aes-256-ctr",
    "bf-cfb",
    "camellia-128-cfb",
    "camellia-192-cfb",
    "camellia-256-cfb",
    "cast5-cfb",
    "des-cfb",
    "idea-cfb",
    "rc2-cfb",
    "seed-cfb",
    "salsa20",
    "chacha20",
    "chacha20-ietf"

The 2022-blake3-* ciphers implement Shadowsocks 2022 (SIP022). They require a base64-encoded pre-shared key supplied with -k: 16 bytes for 2022-blake3-aes-128-gcm and 32 bytes for the other 2022 ciphers. Generate a 32-byte key with openssl rand -base64 32. Passwords are not stretched into keys for these ciphers.

-i <interface>

Send outbound traffic through the specified network interface where supported by the platform.

-c <config_file>

Use a configuration file.

Refer to shadowsocks-c(8) CONFIG FILE section for more details.

-b <local_address>

Specify the local address to use while this client is making outbound connections to the server.

-L <addr:port>

Destination server address and port for local port forwarding.

-a <user_name>

Run as a specific user.

-n <number>

Specify the maximum number of open files. Requires a platform with setrlimit support.

-h

Print help message.

-u

Enable UDP relay.

-U

Enable UDP relay and disable TCP relay.

-v

Enable verbose mode.

-V

Android only: enable VPN socket protection.

-6

Resolve hostname to IPv6 address first.

-A

Deprecated one-time authentication option. Exits with an error; use AEAD ciphers instead.

--fast-open

Enable TCP Fast Open where supported by the operating system.

--mtu <MTU>

Specify the MTU of your network interface.

--no-delay

Enable TCP_NODELAY.

--mptcp

Enable Multipath TCP.

Only available with MPTCP enabled Linux kernel.

--plugin <plugin_name>

Enable SIP003 plugin. (Experimental)

--plugin-opts <plugin_options>

Set SIP003 plugin options. (Experimental)

--reuse-port

Enable port reuse where supported by the operating system.

--tcp-incoming-sndbuf <size>

Set TCP send buffer size for incoming connections.

--tcp-incoming-rcvbuf <size>

Set TCP receive buffer size for incoming connections.

--tcp-outgoing-sndbuf <size>

Set TCP send buffer size for outgoing connections.

--tcp-outgoing-rcvbuf <size>

Set TCP receive buffer size for outgoing connections.

--password <password>

Set the password. The server and the client should use the same password.

--key <key_in_base64>

Set the key directly. The key should be encoded with URL-safe Base64.

--help

Print help message.

EXAMPLE

ss-tunnel(1) can be used to forward DNS queries to a remote DNS server through the shadowsocks tunnel. Here is an example:

# Forward local UDP port 5353 to 8.8.8.8:53 through the ss-server
ss-tunnel -s example.com -p 12345 -l 5353 -k foobar -m aes-256-cfb -L 8.8.8.8:53 -u
 
# Then configure your system to use 127.0.0.1:5353 as the DNS server
dig @127.0.0.1 -p 5353 www.google.com

SEE ALSO

ss-local(1), ss-server(1), ss-redir(1), ss-manager(1), shadowsocks-libev(8), iptables(8), /etc/shadowsocks-libev/config.json