Frp - A Fast Reverse Proxy To Help You Expose A Local Server Behind A NAT Or Firewall To The Internet
A Fast Reverse Proxy To Help You Expose A Local Server Behind A NAT Or Firewall To The Internet.
Development Statusfrp is under development. Try the latest release version in the master
branch, or use the dev
branch for the version in development.
The protocol might change at a release and we don't promise backwards compatibility. Please check the release log when upgrading the client and the server.
Architecture
Example Usage
Firstly, download the latest programs from Release page according to your operating system and architecture.
Put frps
and frps.ini
onto your server A with public IP.
Put frpc
and frpc.ini
onto your server B in LAN (that can't be connected from public Internet).
Access your computer in LAN by SSH
- Modify
frps.ini
on server A and set thebind_port
to be connected to frp clients:
# frps.ini[common]bind_port = 7000
- Start
frps
on server A:
./frps -c ./frps.ini
- On server B, modify
frpc.ini
to put in yourfrps
server public IP asserver_addr
field:
# frpc.ini[common]server_addr = x.x.x.xserver_port = 7000[ssh]type = tcplocal_ip = 127.0.0.1local_port = 22remote_port = 6000
Note that local_port
(listened on client) and remote_port
(exposed on server) are for traffic goes in/out the frp system, whereas server_port
is used between frps.
- Start
frpc
on server B:
./frpc -c ./frpc.ini
- From another machine, SSH to server B like this (assuming that username is
test
):
ssh -oPort=6000 [email protected]
Visit your web service in LAN by custom domains
Sometimes we want to expose a local web service behind a NAT network to others for testing with your own domain name and unfortunately we can't resolve a domain name to a local IP.
However, we can expose an HTTP(S) service using frp.
- Modify
frps.ini
, set the vhost HTTP port to 8080:
# frps.ini[common]bind_port = 7000vhost_http_port = 8080
- Start
frps
:
./frps -c ./frps.ini
- Modify
frpc.ini
and setserver_addr
to the IP address of the remote frps server. Thelocal_port
is the port of your web service:
# frpc.ini[common]server_addr = x.x.x.xserver_port = 7000[web]type = httplocal_port = 80custom_domains = www.example.com
- Start
frpc
:
./frpc -c ./frpc.ini
-
Resolve A record of
www.example.com
to the public IP of the remote frps server or CNAME record to your origin domain. -
Now visit your local web service using url
http://www.example.com:8080
.
Forward DNS query request
- Modify
frps.ini
:
# frps.ini[common]bind_port = 7000
- Start
frps
:
./frps -c ./frps.ini
- Modify
frpc.ini
and setserver_addr
to the IP address of the remote frps server, forward DNS query request to Google Public DNS server8.8.8.8:53
:
# frpc.ini[common]server_addr = x.x.x.xserver_port = 7000[dns]type = udplocal_ip = 8.8.8.8local_port = 53remote_port = 6000
- Start frpc:
./frpc -c ./frpc.ini
- Test DNS resolution using
dig
command:
dig @x.x.x.x -p 6000 www.google.com
Forward Unix domain socket
Expose a Unix domain socket (e.g. the Docker daemon socket) as TCP.
Configure frps
same as above.
- Start
frpc
with configuration:
# frpc.ini[common]server_addr = x.x.x.xserver_port = 7000[unix_domain_socket]type = tcpremote_port = 6000plugin = unix_domain_socketplugin_unix_path = /var/run/docker.sock
- Test: Get Docker version using
curl
:
curl http://x.x.x.x:6000/version
Expose a simple HTTP file server
Browser your files stored in the LAN, from public Internet.
Configure frps
same as above.
- Start
frpc
with configuration:
# frpc.ini[common]server_addr = x.x.x.xserver_port = 7000[test_static_file]type = tcpremote_port = 6000plugin = static_fileplugin_local_path = /tmp/filesplugin_strip_prefix = staticplugin_http_user = abcplugin_http_passwd = abc
- Visit
http://x.x.x.x:6000/static/
from your browser and specify correct user and password to view files in/tmp/files
on thefrpc
machine.
Enable HTTPS for local HTTP service
- Start
frpc
with configuration:
# frpc.ini[common]server_addr = x.x.x.xserver_port = 7000[test_https2http]type = httpscustom_domains = test.example.complugin = https2httpplugin_local_addr = 127.0.0.1:80plugin_crt_path = ./server.crtplugin_key_path = ./server.keyplugin_host_header_rewrite = 127.0.0.1plugin_header_X-From-Where = frp
- Visit
https://test.example.com
.
Expose your service privately
Some services will be at risk if exposed directly to the public network. With STCP (secret TCP) mode, a preshared key is needed to access the service from another client.
Configure frps
same as above.
- Start
frpc
on machine B with the following config. This example is for exposing the SSH service (port 22), and note thesk
field for the preshared key, and that theremote_port
field is removed here:
# frpc.ini[common]server_addr = x.x.x.xserver_port = 7000[secret_ssh]type = stcpsk = abcdefglocal_ip = 127.0.0.1local_port = 22
- Start another
frpc
(typically on another machine C) with the following config to access the SSH service with a security key (sk
field):
# frpc.ini[common]server_addr = x.x.x.xserver_port = 7000[secret_ssh_visitor]type = stcprole = visitorserver_name = secret_sshsk = abcdefgbind_addr = 127.0.0.1bind_port = 6000
- On machine C, connect to SSH on machine B, using this command:
ssh -oPort=6000 127.0.0.1
P2P Mode
xtcp is designed for transmitting large amounts of data directly between clients. A frps server is still needed, as P2P here only refers the actual data transmission.
Note it can't penetrate all types of NAT devices. You might want to fallback to stcp if xtcp doesn't work.
- In
frps.ini
configure a UDP port for xtcp:
# frps.inibind_udp_port = 7001
- Start
frpc
on machine B, expose the SSH port. Note thatremote_port
field is removed:
# frpc.ini[common]server_addr = x.x.x.xserver_port = 7000[p2p_ssh]type = xtcpsk = abcdefglocal_ip = 127.0.0.1local_port = 22
- Start another
frpc
(typically on another machine C) with the config to connect to SSH using P2P mode:
# frpc.ini[common]server_addr = x.x.x.xserver_port = 7000[p2p_ssh_visitor]type = xtcprole = visitorserver_name = p2p_sshsk = abcdefgbind_addr = 127.0.0.1bind_port = 6000
- On machine C, connect to SSH on machine B, using this command:
ssh -oPort=6000 127.0.0.1
Features
Configuration Files
Read the full example configuration files to find out even more features not described here.
Full configuration file for frps (Server)
Full configuration file for frpc (Client)
Using Environment Variables
Environment variables can be referenced in the configuration file, using Go's standard format:
# frpc.ini[common]server_addr = {{ .Envs.FRP_SERVER_ADDR }}server_port = 7000[ssh]type = tcplocal_ip = 127.0.0.1local_port = 22remote_port = {{ .Envs.FRP_SSH_REMOTE_PORT }}
With the config above, variables can be passed into frpc
program like this:
export FRP_SERVER_ADDR="x.x.x.x"export FRP_SSH_REMOTE_PORT="6000"./frpc -c ./frpc.ini
frpc
will render configuration file template using OS environment variables. Remember to prefix your reference with .Envs
.
Dashboard
Check frp's status and proxies' statistics information by Dashboard.
Configure a port for dashboard to enable this feature:
[common]dashboard_port = 7500# dashboard's username and password are both optional,if not set, default is admin.dashboard_user = admindashboard_pwd = admin
Then visit http://[server_addr]:7500
to see the dashboard, with username and password both being admin
by default.
The Admin UI helps you check and manage frpc's configuration.
Configure an address for admin UI to enable this feature:
[common]admin_addr = 127.0.0.1admin_port = 7400admin_user = adminadmin_pwd = admin
Then visit http://127.0.0.1:7400
to see admin UI, with username and password both being admin
by default.
Monitor
When dashboard is enabled, frps will save monitor data in cache. It will be cleared after process restart.
Prometheus is also supported.
Prometheus
Enable dashboard first, then configure enable_prometheus = true
in frps.ini
.
http://{dashboard_addr}/metrics
will provide prometheus monitor data.
Authenticating the Client
There are 2 authentication methods to authenticate frpc with frps.
You can decide which one to use by configuring authentication_method
under [common]
in frpc.ini
and frps.ini
.
Configuring authenticate_heartbeats = true
under [common]
will use the configured authentication method to add and validate authentication on every heartbeat between frpc and frps.
Configuring authenticate_new_work_conns = true
under [common]
will do the same for every new work connection between frpc and frps.
Token Authentication
When specifying authentication_method = token
under [common]
in frpc.ini
and frps.ini
- token based authentication will be used.
Make sure to specify the same token
in the [common]
section in frps.ini
and frpc.ini
for frpc to pass frps validation
OIDC Authentication
When specifying authentication_method = oidc
under [common]
in frpc.ini
and frps.ini
- OIDC based authentication will be used.
OIDC stands for OpenID Connect, and the flow used is called Client Credentials Grant.
To use this authentication type - configure frpc.ini
and frps.ini
as follows:
# frps.ini[common]authentication_method = oidcoidc_issuer = https://example-oidc-issuer.com/oidc_audience = https://oidc-audience.com/.default
# frpc.ini[common]authentication_method = oidcoidc_client_id = 98692467-37de-409a-9fac-bb2585826f18 # Replace with OIDC client IDoidc_client_secret = oidc_secretoidc_audience = https://oidc-audience.com/.defaultoidc_token_endpoint_url = https://example-oidc-endpoint.com/oauth2/v2.0/token
Encryption and Compression
The features are off by default. You can turn on encryption and/or compression:
# frpc.ini[ssh]type = tcplocal_port = 22remote_port = 6000use_encryption = trueuse_compression = true
TLS
frp supports the TLS protocol between frpc
and frps
since v0.25.0.
Config tls_enable = true
in the [common]
section to frpc.ini
to enable this feature.
For port multiplexing, frp sends a first byte 0x17
to dial a TLS connection.
To enforce frps
to only accept TLS connections - configure tls_only = true
in the [common]
section in frps.ini
.
Hot-Reloading frpc configuration
The admin_addr
and admin_port
fields are required for enabling HTTP API:
# frpc.ini[common]admin_addr = 127.0.0.1admin_port = 7400
Then run command frpc reload -c ./frpc.ini
and wait for about 10 seconds to let frpc
create or update or delete proxies.
Note that parameters in [common] section won't be modified except 'start'.
Get proxy status from client
Use frpc status -c ./frpc.ini
to get status of all proxies. The admin_addr
and admin_port
fields are required for enabling HTTP API.
Only allowing certain ports on the server
allow_ports
in frps.ini
is used to avoid abuse of ports:
# frps.ini[common]allow_ports = 2000-3000,3001,3003,4000-50000
allow_ports
consists of specific ports or port ranges (lowest port number, dash -
, highest port number), separated by comma ,
.
Port Reuse
vhost_http_port
and vhost_https_port
in frps can use same port with bind_port
. frps will detect the connection's protocol and handle it correspondingly.
We would like to try to allow multiple proxies bind a same remote port with different protocols in the future.
Bandwidth Limit
For Each Proxy
# frpc.ini[ssh]type = tcplocal_port = 22remote_port = 6000bandwidth_limit = 1MB
Set bandwidth_limit
in each proxy's configure to enable this feature. Supported units are MB
and KB
.
TCP Stream Multiplexing
frp supports tcp stream multiplexing since v0.10.0 like HTTP2 Multiplexing, in which case all logic connections to the same frpc are multiplexed into the same TCP connection.
You can disable this feature by modify frps.ini
and frpc.ini
:
# frps.ini and frpc.ini, must be same[common]tcp_mux = false
Support KCP Protocol
KCP is a fast and reliable protocol that can achieve the transmission effect of a reduction of the average latency by 30% to 40% and reduction of the maximum delay by a factor of three, at the cost of 10% to 20% more bandwidth wasted than TCP.
KCP mode uses UDP as the underlying transport. Using KCP in frp:
- Enable KCP in frps:
# frps.ini[common]bind_port = 7000# Specify a UDP port for KCP.kcp_bind_port = 7000
The kcp_bind_port
number can be the same number as bind_port
, since bind_port
field specifies a TCP port.
- Configure
frpc.ini
to use KCP to connect to frps:
# frpc.ini[common]server_addr = x.x.x.x# Same as the 'kcp_bind_port' in frps.iniserver_port = 7000protocol = kcp
Connection Pooling
By default, frps creates a new frpc connection to the backend service upon a user request. With connection pooling, frps keeps a certain number of pre-established connections, reducing the time needed to establish a connection.
This feature is suitable for a large number of short connections.
- Configure the limit of pool count each proxy can use in
frps.ini
:
# frps.ini[common]max_pool_count = 5
- Enable and specify the number of connection pool:
# frpc.ini[common]pool_count = 1
Load balancing
Load balancing is supported by group
.
This feature is only available for types tcp
and http
now.
# frpc.ini[test1]type = tcplocal_port = 8080remote_port = 80group = webgroup_key = 123[test2]type = tcplocal_port = 8081remote_port = 80group = webgroup_key = 123
group_key
is used for authentication.
Connections to port 80 will be dispatched to proxies in the same group randomly.
For type tcp
, remote_port
in the same group should be the same.
For type http
, custom_domains
, subdomain
, locations
should be the same.
Service Health Check
Health check feature can help you achieve high availability with load balancing.
Add health_check_type = tcp
or health_check_type = http
to enable health check.
With health check type tcp, the service port will be pinged (TCPing):
# frpc.ini[test1]type = tcplocal_port = 22remote_port = 6000# Enable TCP health checkhealth_check_type = tcp# TCPing timeout secondshealth_check_timeout_s = 3# If health check failed 3 times in a row, the proxy will be removed from frpshealth_check_max_failed = 3# A health check every 10 secondshealth_check_interval_s = 10
With health check type http, an HTTP request will be sent to the service and an HTTP 2xx OK response is expected:
# frpc.ini[web]type = httplocal_ip = 127.0.0.1local_port = 80custom_domains = test.example.com# Enable HTTP health checkhealth_check_type = http# frpc will send a GET request to '/status'# and expect an HTTP 2xx OK responsehealth_check_url = /statushealth_check_timeout_s = 3health_check_max_failed = 3health_check_interval_s = 10
Rewriting the HTTP Host Header
By default frp does not modify the tunneled HTTP requests at all as it's a byte-for-byte copy.
However, speaking of web servers and HTTP requests, your web server might rely on the Host
HTTP header to determine the website to be accessed. frp can rewrite the Host
header when forwarding the HTTP requests, with the host_header_rewrite
field:
# frpc.ini[web]type = httplocal_port = 80custom_domains = test.example.comhost_header_rewrite = dev.example.com
The HTTP request will have the the Host
header rewritten to Host: dev.example.com
when it reaches the actual web server, although the request from the browser probably has Host: test.example.com
.
Setting other HTTP Headers
Similar to Host
, You can override other HTTP request headers with proxy type http
.
# frpc.ini[web]type = httplocal_port = 80custom_domains = test.example.comhost_header_rewrite = dev.example.comheader_X-From-Where = frp
Note that parameter(s) prefixed with header_
will be added to HTTP request headers.
In this example, it will set header X-From-Where: frp
in the HTTP request.
Get Real IP
HTTP X-Forwarded-For
This feature is for http proxy only.
You can get user's real IP from HTTP request headers X-Forwarded-For
and X-Real-IP
.
Proxy Protocol
frp supports Proxy Protocol to send user's real IP to local services. It support all types except UDP.
Here is an example for https service:
# frpc.ini[web]type = httpslocal_port = 443custom_domains = test.example.com# now v1 and v2 are supportedproxy_protocol_version = v2
You can enable Proxy Protocol support in nginx to expose user's real IP in HTTP header X-Real-IP
, and then read X-Real-IP
header in your web service for the real IP.
Require HTTP Basic Auth (Password) for Web Services
Anyone who can guess your tunnel URL can access your local web server unless you protect it with a password.
This enforces HTTP Basic Auth on all requests with the username and password specified in frpc's configure file.
It can only be enabled when proxy type is http.
# frpc.ini[web]type = httplocal_port = 80custom_domains = test.example.comhttp_user = abchttp_pwd = abc
Visit http://test.example.com
in the browser and now you are prompted to enter the username and password.
Custom Subdomain Names
It is convenient to use subdomain
configure for http and https types when many people share one frps server.
# frps.inisubdomain_host = frps.com
Resolve *.frps.com
to the frps server's IP. This is usually called a Wildcard DNS record.
# frpc.ini[web]type = httplocal_port = 80subdomain = test
Now you can visit your web service on test.frps.com
.
Note that if subdomain_host
is not empty, custom_domains
should not be the subdomain of subdomain_host
.
URL Routing
frp supports forwarding HTTP requests to different backend web services by url routing.
locations
specifies the prefix of URL used for routing. frps first searches for the most specific prefix location given by literal strings regardless of the listed order.
# frpc.ini[web01]type = httplocal_port = 80custom_domains = web.example.comlocations = /[web02]type = httplocal_port = 81custom_domains = web.example.comlocations = /news,/about
HTTP requests with URL prefix /news
or /about
will be forwarded to web02 and other requests to web01.
TCP Port Multiplexing
frp supports receiving TCP sockets directed to different proxies on a single port on frps, similar to vhost_http_port
and vhost_https_port
.
The only supported TCP port multiplexing method available at the moment is httpconnect
- HTTP CONNECT tunnel.
When setting tcpmux_httpconnect_port
to anything other than 0 in frps under [common]
, frps will listen on this port for HTTP CONNECT requests.
The host of the HTTP CONNECT request will be used to match the proxy in frps. Proxy hosts can be configured in frpc by configuring custom_domain
and / or subdomain
under type = tcpmux
proxies, when multiplexer = httpconnect
.
For example:
# frps.ini[common]bind_port = 7000tcpmux_httpconnect_port = 1337
# frpc.ini[common]server_addr = x.x.x.xserver_port = 7000[proxy1]type = tcpmuxmultiplexer = httpconnectcustom_domains = test1[proxy2]type = tcpmuxmultiplexer = httpconnectcustom_domains = test2
In the above configuration - frps can be contacted on port 1337 with a HTTP CONNECT header such as:
CONNECT test1 HTTP/1.1\r\n\r\n
and the connection will be routed to proxy1
.
Connecting to frps via HTTP PROXY
frpc can connect to frps using HTTP proxy if you set OS environment variable HTTP_PROXY
, or if http_proxy
is set in frpc.ini file.
It only works when protocol is tcp.
# frpc.ini[common]server_addr = x.x.x.xserver_port = 7000http_proxy = http://user:[email protected]:8080
Range ports mapping
Proxy with names that start with range:
will support mapping range ports.
# frpc.ini[range:test_tcp]type = tcplocal_ip = 127.0.0.1local_port = 6000-6006,6007remote_port = 6000-6006,6007
frpc will generate 8 proxies like test_tcp_0
, test_tcp_1
, ..., test_tcp_7
.
Client Plugins
frpc only forwards requests to local TCP or UDP ports by default.
Plugins are used for providing rich features. There are built-in plugins such as unix_domain_socket
, http_proxy
, socks5
, static_file
and you can see example usage.
Specify which plugin to use with the plugin
parameter. Configuration parameters of plugin should be started with plugin_
. local_ip
and local_port
are not used for plugin.
Using plugin http_proxy:
# frpc.ini[http_proxy]type = tcpremote_port = 6000plugin = http_proxyplugin_http_user = abcplugin_http_passwd = abc
plugin_http_user
and plugin_http_passwd
are configuration parameters used in http_proxy
plugin.
Server Manage Plugins
Read the document.
Find more plugins in gofrp/plugin.
Development Plan
- Log HTTP request information in frps.
Contributing
Interested in getting involved? We would like to help you!
- Take a look at our issues list and consider sending a Pull Request to dev branch.
- If you want to add a new feature, please create an issue first to describe the new feature, as well as the implementation approach. Once a proposal is accepted, create an implementation of the new features and submit it as a pull request.
- Sorry for my poor English. Improvements for this document are welcome, even some typo fixes.
- If you have great ideas, send an email to [email protected].
Note: We prefer you to give your advise in issues, so others with a same question can search it quickly and we don't need to answer them repeatedly.
Via: feedproxy.google.com