oauth2_proxy/README.md
2014-11-09 21:12:36 -05:00

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google_auth_proxy
=================
A reverse proxy that provides authentication using Google OAuth2 to validate
individual accounts, or a whole google apps domain.
[![Build Status](https://secure.travis-ci.org/bitly/google_auth_proxy.png?branch=master)](http://travis-ci.org/bitly/google_auth_proxy)
## Architecture
```
_______ ___________________ __________
|Nginx| ----> |google_auth_proxy| ----> |upstream|
------- ------------------- ----------
||
\/
[google oauth2 api]
```
## Installation
1. [Install Go](http://golang.org/doc/install)
2. `$ go get github.com/bitly/google_auth_proxy`. This should put the binary in `$GOROOT/bin`
## OAuth Configuration
You will need to register an OAuth application with google, and configure it with Redirect URI(s) for the domain you
intend to run `google_auth_proxy` on.
1. Create a new project: https://console.developers.google.com/project
2. Under "APIs & Auth", choose "Credentials"
3. Now, choose "Create new Client ID"
* The Application Type should be **Web application**
* Enter your domain in the Authorized Javascript Origins `https://internal.yourcompany.com`
* Enter the correct Authorized Redirect URL `https://internal.yourcompany.com/oauth2/callback`
* NOTE: `google_auth_proxy` will _only_ callback on the path `/oauth2/callback`
4. Under "APIs & Auth" choose "Consent Screen"
* Fill in the necessary fields and Save (this is _required_)
5. Take note of the **Client ID** and **Client Secret**
## Configuration
`google_auth_proxy` can be configured via [config file](#config-file), [command line options](#command-line-options) or [environment variables](#environment-variables).
### Config File
An example [google_auth_proxy.cfg](contrib/google_auth_proxy.cfg.example) config file is in the contrib directory. It can be used by specifying `-config=/etc/google_auth_proxy.cfg`
### Command Line Options
```
Usage of google_auth_proxy:
-authenticated-emails-file="": authenticate against emails via file (one per line)
-client-id="": the Google OAuth Client ID: ie: "123456.apps.googleusercontent.com"
-client-secret="": the OAuth Client Secret
-config="": path to config file
-cookie-domain="": an optional cookie domain to force cookies to (ie: .yourcompany.com)
-cookie-expire=168h0m0s: expire timeframe for cookie
-cookie-https-only=false: set HTTPS only cookie
-cookie-secret="": the seed string for secure cookies
-google-apps-domain=: authenticate against the given Google apps domain (may be given multiple times)
-htpasswd-file="": additionally authenticate against a htpasswd file. Entries must be created with "htpasswd -s" for SHA encryption
-http-address="127.0.0.1:4180": <addr>:<port> to listen on for HTTP clients
-pass-basic-auth=true: pass HTTP Basic Auth, X-Forwarded-User and X-Forwarded-Email information to upstream
-redirect-url="": the OAuth Redirect URL. ie: "https://internalapp.yourcompany.com/oauth2/callback"
-upstream=: the http url(s) of the upstream endpoint. If multiple, routing is based on path
-version=false: print version string
```
### Environment variables
The environment variables `GOOGLE_AUTH_PROXY_CLIENT_ID`, `GOOGLE_AUTH_PROXY_CLIENT_SECRET`, `GOOGLE_AUTH_PROXY_COOKIE_SECRET`, `GOOGLE_AUTH_PROXY_COOKIE_DOMAIN` and `GOOGLE_AUTH_PROXY_COOKIE_EXPIRE` can be used in place of the corresponding command-line arguments.
### Example Nginx Configuration
This example has a [Nginx](http://nginx.org/) SSL endpoint proxying to `google_auth_proxy` on port `4180`.
`google_auth_proxy` then authenticates requests for an upstream application running on port `8080`. The external
endpoint for this example would be `https://internal.yourcompany.com/`.
An example Nginx config follows. Note the use of `Strict-Transport-Security` header to pin requests to SSL
via [HSTS](http://en.wikipedia.org/wiki/HTTP_Strict_Transport_Security):
```
server {
listen 443 default ssl;
server_name internal.yourcompany.com;
ssl_certificate /path/to/cert.pem;
ssl_certificate_key /path/to/cert.key;
add_header Strict-Transport-Security max-age=1209600;
location / {
proxy_pass http://127.0.0.1:4180;
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Scheme $scheme;
proxy_connect_timeout 1;
proxy_send_timeout 30;
proxy_read_timeout 30;
}
}
```
The command line to run `google_auth_proxy` would look like this:
```bash
./google_auth_proxy \
--redirect-url="https://internal.yourcompany.com/oauth2/callback" \
--google-apps-domain="yourcompany.com" \
--upstream=http://127.0.0.1:8080/ \
--cookie-secret=... \
--cookie-secure=true \
--client-id=... \
--client-secret=...
```
## Endpoint Documentation
Google Auth Proxy responds directly to the following endpoints. All other endpoints will be proxied upstream when authenticated.
* /ping - returns an 200 OK response
* /oauth2/sign_in - the login page, which also doubles as a sign out page (it clears cookies)
* /oauth2/start - a URL that will redirect to start the OAuth cycle
* /oauth2/callback - the URL used at the end of the OAuth cycle