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Apache uses port 80 for plain http connections and port 443 for TLS/SSL connections by default. To make this service available from other computers or the Internet your have to allow Apache through the firewall like this: | Apache uses port 80 for plain http connections and port 443 for TLS/SSL connections by default. To make this service available from other computers or the Internet your have to allow Apache through the firewall like this: | ||
To open the firewall at each boot: | |||
For plain HTTP connections: | For plain HTTP connections: | ||
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For TLS/SSL connections: | For TLS/SSL connections: | ||
# firewall-cmd --permanent --add-service=https | # firewall-cmd --permanent --add-service=https | ||
To open the firewall right now: | |||
For plain HTTP connections: | |||
# firewall-cmd --add-service=http | |||
For TLS/SSL connections: | |||
# firewall-cmd --add-service=https | |||
Remember that if your server is running behind a NAT router, you will also need to configure your router to forward the HTTP and HTTPS ports to your server if you wish to allow access from outside your local network. | Remember that if your server is running behind a NAT router, you will also need to configure your router to forward the HTTP and HTTPS ports to your server if you wish to allow access from outside your local network. |
Revision as of 12:39, 29 August 2014
The Apache HTTP Server is one of the most commonly-used web servers. This page acts as a quick start guide to deploying and configuring Apache on Fedora. For (many) more details, please see upstream's extensive documentation.
Installation
$ su # yum install httpd
If you want TLS/SSL support, you can also install mod_ssl
, which is based on OpenSSL. Alternatives are mod_gnutls
(uses GnuTLS) and mod_nss
(uses NSS).
# yum install mod_ssl
To have the server start at each boot:
# systemctl enable httpd.service
To start the server now:
# systemctl start httpd.service
At this point, you should be able to browse to http://localhost on the server and access the Apache test page. You will most likely not be able to access the server from any other host, yet: we will change this later.
Create a self signed TLS/SSL certificate
If you want to use TLS/SSL, you will need a server certificate. The simplest choice is to create a 'self-signed' certificate; this does not require you to deal with a certificate signing authority, but means no system will trust your server by default. You may publish and/or note down the key's fingerprint and verify it each time you connect to your server.
# cd /etc/pki/tls/certs # make testcert
If your server already has a valid certificate and you want to replace it, pass SERIAL= to set a different serial number so that clients notice the change in certificate and update to the new one without failing. The first certificate you generate will likely have had a serial number of 0, so the first time you replace it, set it to 1, then increment each time you replace it after that.
# cd /etc/pki/tls/certs # make testcert SERIAL=1
Answer the questions as they come up, but don't sweat the answers too much (more detailed documentation can explain what the various fields in a TLS certificate mean, if you are interested). After completing this, you should have new files /etc/pki/tls/certs/localhost.crt
and /etc/pki/tls/private/localhost.key
- the former is your self-signed server certificate, and the latter is the corresponding private key.
The default configuration of mod_ssl uses the filenames generated by make testcert
, so no further configuration is needed.
Keys generated in this way have a passphrase (you will be asked to enter one during generation). Any time you start or restart Apache (including any time the system is booted), you will have to enter this passphrase: Apache startup will not proceed unless it is entered. If you find this impractical, you can strip the passphrase from the key:
Back up the key first # cp localhost.key localhost.key.bak # openssl rsa -in localhost.key -out localhost.key.new # mv localhost.key.new localhost.key # restorecon localhost.key
If you do this, it is essential that you guard the localhost.key
file carefully, as anyone who gains access to it can impersonate your server and intercept 'secure' traffic. Ensure it is owned by root.root and has permissions 0600, be very careful about security of backups, and restrict access to the server machine as strictly as you can (this is a good security practice in any case).
If you want to have a certificate signed by some authority which will be trusted by others, you can generate a certificate signing request (CSR) instead of a certificate by running make certreq
instead of make testcert
. You can then provide that CSR to the signing authority and they will provide you with a signed certificate: you should either save this certificate as /etc/pki/tls/certs/localhost.crt
, or save it as another filename and modify the mod_ssl configuration to point to the correct file (see below).
Install an existing certificate
If you already have a certificate generated on another computer, move the certificate and the key file to the correct folder, and ensure their SELinux contexts, ownerships and permissions are correct:
# mv key_file.key /etc/pki/tls/private/localhost.key # restorecon /etc/pki/tls/private/localhost.key # chown root.root /etc/pki/tls/private/localhost.key # chmod 0600 /etc/pki/tls/private/localhost.key # mv certificate.crt /etc/pki/tls/certs/localhost.crt # restorecon /etc/pki/tls/private/localhost.crt # chown root.root /etc/pki/tls/private/localhost.crt # chmod 0600 /etc/pki/tls/private/localhost.crt
Installing webapps
You probably want to run something on your web server. Many of the most popular 'web applications' are packaged for Fedora. Using the packaged versions of web applications is usually recommended: they will be configured following the distribution's best practices which help to ensure the security of the installation, for instance by installing static files to locations the web server does not have the ability to write to, and doing access control with configuration files rather than .htaccess
files, which are slightly more vulnerable to attack.
Packaged web applications will also be configured to work with SELinux, which provides significant security benefits.
You will also receive updates through the usual Fedora update process, making it easier to keep your installation up to date.
They will also often have the default configuration tweaked according to Fedora's conventions, meaning you have to do less work to get the application up and running.
Most web applications are simply packaged according to their name. For example, you can install Wordpress with:
# yum install wordpress
Packaged web applications will usually provide Fedora-specific instructions in a documentation file - for instance, Wordpress provides the files /usr/share/doc/wordpress/README.fedora
and /usr/share/doc/wordpress/README.fedora-multiuser
. It is always a good idea to read these files!
Packaged web applications usually restrict access by default so you can access them only from the server host itself, to ensure you can run all initial configuration safely and things like administration interfaces are not left accessible to the public. For information on how to broaden access, see below.
Web applications commonly require the use of a database server. This wiki contains information on installing and configuring PostgreSQL and MariaDB on Fedora.
Configuration
/etc/httpd/conf/httpd.conf
is the main Apache configuration file. It includes all the files in /etc/httpd/conf.d/
: if the same setting is specified in both /etc/httpd/conf/httpd.conf
and a file in /etc/httpd/conf.d/
, the setting from the /etc/httpd/conf.d/
file will win. Files in /etc/httpd/conf.d/
are read in alphabetical order: a setting from /etc/httpd/conf.d/z-foo.conf
will win over a setting from /etc/httpd/conf.d/foo.conf
, which will win over a setting from /etc/httpd/conf.d/99-foo.conf
, which will win over a setting from /etc/httpd/conf.d/00-foo.conf
.
It is usually best practice never to modify /etc/httpd/conf/httpd.conf
or any of the /etc/httpd/conf.d
files shipped by Fedora packages directly. If you make any local changes to these files, then any changes to them in newer package versions will not be directly applied: instead a .rpmnew
file will be created and you will have to merge the changes manually. It is usually better instead to create a new file in /etc/httpd/conf.d
which will take precedence over the file you wish to 'modify', and make your settings there. For instance, to change a setting specified in /etc/httpd/conf.d/foo.conf
you could create the file /etc/httpd/conf.d/z-foo-local.conf
and place your setting in that file. We will see an example of this next.
After making any changes to your server configuration, you should run:
# apachectl reload
to apply the changes. Certain changes may require Apache to be fully restarted:
# systemctl restart httpd.service
TLS/SSL configuration
The default TLS/SSL configuration is contained in the file /etc/httpd/conf.d/ssl.conf
(if you are using mod_ssl
). If you examine that file, you will see the directives that specify where the TLS/SSL certificate and key are located:
SSLCertificateFile /etc/pki/tls/certs/localhost.crt SSLCertificateKeyFile /etc/pki/tls/private/localhost.key
If you look carefully, you will see that these directives are actually enclosed in a block defining a virtual host:
<VirtualHost _default_:443> ... SSLCertificateFile /etc/pki/tls/certs/localhost.crt ... SSLCertificateKeyFile /etc/pki/tls/private/localhost.key ... </VirtualHost>
If we wanted to define a different location for these files, we could edit the lines in /etc/httpd/conf.d/ssl.conf
directly, but it would be better to create a new file /etc/httpd/conf.d/z-ssl-local.conf
:
<VirtualHost _default_:443> SSLCertificateFile /etc/pki/tls/certs/www.myhost.org.crt SSLCertificateKeyFile /etc/pki/tls/private/www.myhost.org.key </VirtualHost>
This file will override those two settings for the _default_:443 virtual host; all other settings from ssl.conf
will be kept.
Settings for individual virtual hosts
If you want a specific virtual host to use SSL/TLS with a different certificate from the default, open that virtual host's configuration file, usually /etc/httpd/conf.d/hostname.conf
, and insert these lines between <VirtualHost hostname:port> and </VirtualHost>:
SSLEngine on SSLCertificateFile /etc/pki/tls/certs/hostname.crt
SSLCertificateKeyFile /etc/pki/tls/private/hostname.key
Enabling access to web applications
Fedora-packaged web applications are usually configured such that, by default, access is allowed only from localhost. Typically you will find that there is a file /etc/httpd/conf.d/webapp.conf
with the following (among other settings):
<Directory /usr/share/webapp> <IfModule mod_authz_core.c> # Apache 2.4 Require local </IfModule> <IfModule !mod_authz_core.c> # Apache 2.2 Order Deny,Allow Deny from all Allow from 127.0.0.1 Allow from ::1 </IfModule> </Directory>
Before allowing general access to the webapp, ensure you have configured it correctly and the administration interface and other sensitive areas are not accessible without appropriate authentication. Also remember to ensure your database configuration is secure, if the application uses a database. To broaden access to the application, you can create a file /etc/httpd/conf.d/z-webapp-allow.conf
. To allow access to all systems on a typical local network, you could write:
<Directory /usr/share/webapp> <IfModule mod_authz_core.c> # Apache 2.4 Require local Require ip 192.168.1 </IfModule> <IfModule !mod_authz_core.c> # Apache 2.2 Order Deny,Allow Deny from all Allow from 127.0.0.1 Allow from ::1 Allow from 192.168.1 </IfModule> </Directory>
Once you are sure the application is correctly configured, this configuration will allow access from any host:
<Directory /usr/share/webapp> <IfModule mod_authz_core.c> # Apache 2.4 Require all granted </IfModule> <IfModule !mod_authz_core.c> # Apache 2.2 Order Deny,Allow Allow from all </IfModule> </Directory>
Opening firewall ports
Apache uses port 80 for plain http connections and port 443 for TLS/SSL connections by default. To make this service available from other computers or the Internet your have to allow Apache through the firewall like this:
To open the firewall at each boot:
For plain HTTP connections:
# firewall-cmd --permanent --add-service=http
For TLS/SSL connections:
# firewall-cmd --permanent --add-service=https
To open the firewall right now:
For plain HTTP connections:
# firewall-cmd --add-service=http
For TLS/SSL connections:
# firewall-cmd --add-service=https
Remember that if your server is running behind a NAT router, you will also need to configure your router to forward the HTTP and HTTPS ports to your server if you wish to allow access from outside your local network.
Disable test page
To disable the test page comment out all the lines in the file /etc/httpd/conf.d/welcome.conf