HTTP header improvements (#294)

[akkoma] / docs / docs / installation / openbsd_en.md

# Installing on OpenBSD

This guide describes the installation and configuration of akkoma (and the required software to run it) on a single OpenBSD 6.6 server.

For any additional information regarding commands and configuration files mentioned here, check the man pages [online](https://man.openbsd.org/) or directly on your server with the man command.

{! installation/generic_dependencies.include !}

### Preparing the system
#### Required software

To install them, run the following command (with doas or as root):

```
pkg_add elixir gmake git postgresql-server postgresql-contrib cmake ffmpeg ImageMagick
```

Akkoma requires a reverse proxy, OpenBSD has relayd in base (and is used in this guide) and packages/ports are available for nginx (www/nginx) and apache (www/apache-httpd). Independently of the reverse proxy, [acme-client(1)](https://man.openbsd.org/acme-client) can be used to get a certificate from Let's Encrypt.

#### Optional software

Per [`docs/installation/optional/media_graphics_packages.md`](../installation/optional/media_graphics_packages.md):
  * ImageMagick
  * ffmpeg
  * exiftool

To install the above:

```
pkg_add ImageMagick ffmpeg p5-Image-ExifTool
```

#### Creating the akkoma user
Akkoma will be run by a dedicated user, \_akkoma. Before creating it, insert the following lines in login.conf:
```
akkoma:\
        :datasize-max=1536M:\
        :datasize-cur=1536M:\
        :openfiles-max=4096
```
This creates a "akkoma" login class and sets higher values than default for datasize and openfiles (see [login.conf(5)](https://man.openbsd.org/login.conf)), this is required to avoid having akkoma crash some time after starting.

Create the \_akkoma user, assign it the akkoma login class and create its home directory (/home/\_akkoma/): `useradd -m -L akkoma _akkoma`

#### Clone akkoma's directory
Enter a shell as the \_akkoma user. As root, run `su _akkoma -;cd`. Then clone the repository with `git clone https://akkoma.dev/AkkomaGang/akkoma.git`. Akkoma is now installed in /home/\_akkoma/akkoma/, it will be configured and started at the end of this guide.

#### PostgreSQL
Start a shell as the \_postgresql user (as root run `su _postgresql -` then run the `initdb` command to initialize postgresql:
You will need to specify pgdata directory to the default (/var/postgresql/data) with the `-D <path>` and set the user to postgres with the `-U <username>` flag. This can be done as follows:

```
initdb -D /var/postgresql/data -U postgres
```
If you are not using the default directory, you will have to update the `datadir` variable in the /etc/rc.d/postgresql script.

When this is done, enable postgresql so that it starts on boot and start it. As root, run:
```
rcctl enable postgresql
rcctl start postgresql
```
To check that it started properly and didn't fail right after starting, you can run `ps aux | grep postgres`, there should be multiple lines of output.

#### httpd
httpd will have three fuctions:

  * redirect requests trying to reach the instance over http to the https URL
  * serve a robots.txt file
  * get Let's Encrypt certificates, with acme-client

Insert the following config in httpd.conf:
```
# $OpenBSD: httpd.conf,v 1.17 2017/04/16 08:50:49 ajacoutot Exp $

ext_inet="<IPv4 address>"
ext_inet6="<IPv6 address>"

server "default" {
        listen on $ext_inet port 80 # Comment to disable listening on IPv4
        listen on $ext_inet6 port 80 # Comment to disable listening on IPv6
        listen on 127.0.0.1 port 80 # Do NOT comment this line

        log syslog
        directory no index

        location "/.well-known/acme-challenge/*" {
                root "/acme"
                request strip 2
        }

        location "/robots.txt" { root "/htdocs/local/" }
        location "/*" { block return 302 "https://$HTTP_HOST$REQUEST_URI" }
}

types {
}
```
Do not forget to change *<IPv4/6 address\>* to your server's address(es). If httpd should only listen on one protocol family, comment one of the two first *listen* options.

Create the /var/www/htdocs/local/ folder and write the content of your robots.txt in /var/www/htdocs/local/robots.txt.
Check the configuration with `httpd -n`, if it is OK enable and start httpd (as root):
```
rcctl enable httpd
rcctl start httpd
```

#### acme-client
acme-client is used to get SSL/TLS certificates from Let's Encrypt.
Insert the following configuration in /etc/acme-client.conf:
```
#
# $OpenBSD: acme-client.conf,v 1.4 2017/03/22 11:14:14 benno Exp $
#

authority letsencrypt-<domain name> {
        #agreement url "https://letsencrypt.org/documents/LE-SA-v1.2-November-15-2017.pdf"
        api url "https://acme-v02.api.letsencrypt.org/directory"
        account key "/etc/acme/letsencrypt-privkey-<domain name>.pem"
}

domain <domain name> {
        domain key "/etc/ssl/private/<domain name>.key"
        domain certificate "/etc/ssl/<domain name>.crt"
        domain full chain certificate "/etc/ssl/<domain name>.fullchain.pem"
        sign with letsencrypt-<domain name>
        challengedir "/var/www/acme/"
}
```
Replace *<domain name\>* by the domain name you'll use for your instance. As root, run `acme-client -n` to check the config, then `acme-client -ADv <domain name>` to create account and domain keys, and request a certificate for the first time.
Make acme-client run everyday by adding it in /etc/daily.local. As root, run the following command: `echo "acme-client <domain name>" >> /etc/daily.local`.

Relayd will look for certificates and keys based on the address it listens on (see next part), the easiest way to make them available to relayd is to create a link, as root run:
```
ln -s /etc/ssl/<domain name>.fullchain.pem /etc/ssl/<IP address>.crt
ln -s /etc/ssl/private/<domain name>.key /etc/ssl/private/<IP address>.key
```
This will have to be done for each IPv4 and IPv6 address relayd listens on.

#### relayd
relayd will be used as the reverse proxy sitting in front of akkoma.
Insert the following configuration in /etc/relayd.conf:
```
# $OpenBSD: relayd.conf,v 1.4 2018/03/23 09:55:06 claudio Exp $

ext_inet="<IPv4 address>"
ext_inet6="<IPv6 address>"

table <akkoma_server> { 127.0.0.1 }
table <httpd_server> { 127.0.0.1 }

http protocol plerup { # Protocol for upstream akkoma server
        #tcp { nodelay, sack, socket buffer 65536, backlog 128 } # Uncomment and adjust as you see fit
        tls ciphers "ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305"
        tls ecdhe secp384r1

        # Forward some paths to the local server (as akkoma won't respond to them as you might want)
        pass request quick path "/robots.txt" forward to <httpd_server>

        # Append a bunch of headers
        match request header append "X-Forwarded-For" value "$REMOTE_ADDR" # This two header and the next one are not strictly required by akkoma but adding them won't hurt
        match request header append "X-Forwarded-By" value "$SERVER_ADDR:$SERVER_PORT"

        match response header append "X-XSS-Protection" value "0"
        match response header append "X-Permitted-Cross-Domain-Policies" value "none"
        match response header append "X-Frame-Options" value "DENY"
        match response header append "X-Content-Type-Options" value "nosniff"
        match response header append "Referrer-Policy" value "same-origin"
        match response header append "Content-Security-Policy" value "default-src 'none'; base-uri 'none'; form-action 'self'; img-src 'self' data: https:; media-src 'self' https:; style-src 'self' 'unsafe-inline'; font-src 'self'; script-src 'self'; connect-src 'self' wss://CHANGEME.tld; upgrade-insecure-requests;" # Modify "CHANGEME.tld" and set your instance's domain here
        match request header append "Connection" value "upgrade"
        #match response header append "Strict-Transport-Security" value "max-age=63072000; includeSubDomains; preload" # Uncomment this only after you get HTTPS working.

        # If you do not want remote frontends to be able to access your Akkoma backend server, comment these lines
        match response header append "Access-Control-Allow-Origin" value "*"
        match response header append "Access-Control-Allow-Methods" value "POST, PUT, DELETE, GET, PATCH, OPTIONS"
        match response header append "Access-Control-Allow-Headers" value "Authorization, Content-Type, Idempotency-Key"
        match response header append "Access-Control-Expose-Headers" value "Link, X-RateLimit-Reset, X-RateLimit-Limit, X-RateLimit-Remaining, X-Request-Id"
        # Stop commenting lines here
}

relay wwwtls {
        listen on $ext_inet port https tls # Comment to disable listening on IPv4
        listen on $ext_inet6 port https tls # Comment to disable listening on IPv6

        protocol plerup

        forward to <akkoma_server> port 4000 check http "/" code 200
        forward to <httpd_server> port 80 check http "/robots.txt" code 200
}
```
Again, change *<IPv4/6 address\>* to your server's address(es) and comment one of the two *listen* options if needed. Also change *wss://CHANGEME.tld* to *wss://<your instance's domain name\>*.
Check the configuration with `relayd -n`, if it is OK enable and start relayd (as root):
```
rcctl enable relayd
rcctl start relayd
```

#### pf
Enabling and configuring pf is highly recommended.
In /etc/pf.conf, insert the following configuration:
```
# Macros
if="<network interface>"
authorized_ssh_clients="any"

# Skip traffic on loopback interface
set skip on lo

# Default behavior
set block-policy drop
block in log all
pass out quick

# Security features
match in all scrub (no-df random-id)
block in log from urpf-failed

# Rules
pass in quick on $if inet proto icmp to ($if) icmp-type { echoreq unreach paramprob trace } # ICMP
pass in quick on $if inet6 proto icmp6 to ($if) icmp6-type { echoreq unreach paramprob timex toobig } # ICMPv6
pass in quick on $if proto tcp to ($if) port { http https } # relayd/httpd
pass in quick on $if proto tcp from $authorized_ssh_clients to ($if) port ssh
```
Replace *<network interface\>* by your server's network interface name (which you can get with ifconfig). Consider replacing the content of the authorized\_ssh\_clients macro by, for exemple, your home IP address, to avoid SSH connection attempts from bots.

Check pf's configuration by running `pfctl -nf /etc/pf.conf`, load it with `pfctl -f /etc/pf.conf` and enable pf at boot with `rcctl enable pf`.

#### Configure and start akkoma
Enter a shell as \_akkoma (as root `su _akkoma -`) and enter akkoma's installation directory (`cd ~/akkoma/`).

Then follow the main installation guide:

  * run `mix deps.get`
  * run `MIX_ENV=prod mix pleroma.instance gen` and enter your instance's information when asked
  * copy config/generated\_config.exs to config/prod.secret.exs. The default values should be sufficient but you should edit it and check that everything seems OK.
  * exit your current shell back to a root one and run `psql -U postgres -f /home/_akkoma/akkoma/config/setup_db.psql` to setup the database.
  * return to a \_akkoma shell into akkoma's installation directory (`su _akkoma -;cd ~/akkoma`) and run `MIX_ENV=prod mix ecto.migrate`

As \_akkoma in /home/\_akkoma/akkoma, you can now run `LC_ALL=en_US.UTF-8 MIX_ENV=prod mix phx.server` to start your instance.
In another SSH session/tmux window, check that it is working properly by running `ftp -MVo - http://127.0.0.1:4000/api/v1/instance`, you should get json output. Double-check that *uri*'s value is your instance's domain name.

##### Starting akkoma at boot
An rc script to automatically start akkoma at boot hasn't been written yet, it can be run in a tmux session (tmux is in base).


#### Create administrative user

If your instance is up and running, you can create your first user with administrative rights with the following command as the \_akkoma user.
```
LC_ALL=en_US.UTF-8 MIX_ENV=prod mix pleroma.user new <username> <your@emailaddress> --admin
```

{! installation/frontends.include !}

#### Further reading

{! installation/further_reading.include !}

{! support.include !}