INSTALL

# Table of Contents

In this document (see INSTALL.html for the formatted version of this INSTALL file):

- Requirements
- Installation overview
- Dependencies
- What gets installed
- For more information
- Starting and stopping the authentication daemon
- Guidelines for using other package managers

## Requirements

See the README file for a general description of this library. The following software should be installed before building the Courier authentication library:

- The current version of gcc (http://www.gnu.org/software/gcc/)
- The GNU linker (http://www.gnu.org/software/binutils/)
- Libtool (http://www.gnu.org/software/libtool/). Additional, libtool's `libltdl` library, and its development files, must be installed. On some platforms this is a separate package. On Fedora, this is the `libtool-ltdl-devel` package, for example.
- GNU make (http://www.gnu.org/software/make/)
- The "`expect`" command. `expect` is usually included with most systems. `Expect` can be downloaded from `http://expect.nist.gov/` if it's not installed on your system. This utility is used to change system login passwords, by scripting the `passwd` command. If you do not have `expect` installed you will not be able to change system login passwords. However non-system authentication modules (LDAP, PostgreSQL, and others) will work.
- Courier Unicode Library. Before installing this package, download and install https://www.courier-mta.org/unicode/.

Courier-authlib uses Libtool to build shared libraries. Libtool must be installed, together with its `libltdl` library and its header files.

On non-Linux platforms the GNU linker is also required. Courier-authlib's build script uses some GNU linker-specific options. It's possible to manually specify the native linker's equivalent options manually, if they exist. If the native linker does not have the equivalent options, the GNU linker will have to be installed.

On the other hand, GNU make will be required in almost every case. SYSV-derived make variants (probably) will not work.

The same line of logic also applies to gcc. So, strictly speaking, only a basic C compiler, GNU make and libtool, are really needed to build courier-authlib. Still, try the following before giving up if problems occur when building this package:

1. Install a recent version of the GNU linker
2. Install the current version of Libtool
3. Install the current version of gcc

## Installation overview

### rpm and deb packages

These are not the same packages as the ones from the distributions' repositories. These packages carry a higher internal revision level in order to prevent them from getting upgraded by the distributions' packages. This packaging exists in order to have a convenient way of updating after a release without waiting for the distributions' packages to get built.

NOTE: If a distribution package is already installed it should be removed completely before switching to the upstream version (dnf remove or apt purge). Preserve any existing configuration files, beforehand, in order to restore it after switching packages. This applies to all Courier packages. A switch to this courier-authlib package requires switching to the courier-unicode package too.

NOTE: These packages use their own, generic, installation layout that may deviate slightly from the package installation conventions preferred by the distributions.

### rpm

Run `dnf install rpm-build` if it's not installed already, then:

    rpmbuild -ta courier-authlib-VERSION.tar.bz2

If this fails due to any missing dependencies, install them. This builds: the main (runtime libraries); a subpackage for each authentication module (LDAP, MySQL, etc...); the development (link libraries, header files) package. All development libraries needed to build all authentication modules must be installed to build the rpms, but do not need to be installed at runtime unless the corresponding authentication module rpm is also installed.

This creates rpms that can be installed with "rpm -U":

- The "courier-authlib" package with the commands and standard authentication modules.
- The "courier-authlib-devel" package with development libraries and header files.
- The "courier-authlib-config-username-groupname package. This is a metapackage that captures the user/group used by the authentication library (daemon/daemon) by default. The dependencies on the metapackage are set up in a way to prevent unitended updates to an incompatible newer version that's configured with different user and group names.
- Other "courier-authlib-name" authentication modules.

#### Using non-default courier username and groupname

Pass --define "mailuser courier" and --define "mailgroup courier" options to rpmbuild to build the library with a non-default user and group name.

### deb

Run "apt install devscripts debhelper", if they're not installed already. Create an empty directory and copy/move the tarball into it:

    $ mkdir tmp
    $ mv courier-authlib-VERSION.tar.bz2 tmp
    $ cd tmp

Unpack the tarball and cd into the unpacked subdirectory:

    $ tar xvf courier-authlib-VERSION.tar.bz2
    $ cd courier-authlib-VERSION

Run the `courier-debuild` script, which is a wrapper for `debuild`, and forwards its parameters to it:

    $ ./courier-debuild -us -uc

NOTE: the above steps must be followed strictly. The courier-debuild script expects the distributed tarball in its parent directory.

This eventually produces a deb subdirectory with .deb packages that can be installed with "dpkg -i":

- The "libcourier-auth" package with the commands and standard authentication modules; and "libcourier-auth-<N>" with versioned client shared libraries.
- The "libcourier-auth-dev" package with development libraries and header files.
- Other "libcourier-auth-name" authentication modules.
- The "libcourier-auth-config-mailuser-mailgroup" package. This package sets up the reserved user and group id the library and the rest of the Courier packages use. When the built .deb packages get manually installed directly with dpkg this "config" package must get installed first, by itself, followed by the rest of the packages. Higher level tools, like apt should figure this out by themselves.

    $ DEBGCC=10 ./courier-debuild -us -uc

Setting the `DEBGCC` environment variable selects a non-default gcc version.

NOTE: all Courier packages should be built using the same version of gcc.

#### Using non-default courier username and groupname

    $ mailuser=courier mailgroup=courier ./courier-debuild -us -uc

Setting the `mailuser` and `mailgroup` environment builds the library with a non-default user and group name.

### Maintainer Mode (see README in the git repository to set up)

make rpm or make deb, as appropriate, will:

1. Increment an internal release number.

2. Run make dist.

3. Proceed and build a new release, creating the native packages in the rpm or deb subdirectory.

4. Execute either $HOME/bin/rpmrepos.sh or $HOME/bin/debrepos.sh. This can be a script that does nothing, or it's intended to be the maintainer's script that pushes out the packages to a repository.

### Manual installation

The following sequence of commands should be sufficient to install courier-authlib in most cases:

    ./configure [options] [variable=value]*...
    make
    make install
    make install-configure

> NOTE: On the BSD family, GNU make is usually the 'gmake' command. Use the 'gmake' command, instead of 'make'.

The '`make install-configure`' command is required; it installs and updates the configuration files; this command must be executed when installing courier-authlib for the first time, and when upgrading from an older version.

### Configuration options

The configure script takes the usual `autoconf` options: `--prefix`, `--bindir`, and the rest of the usual toolchain options. The default installation directories should be sufficient, though.

DO NOT USE the `--disable-static`, or `--enable-static=no` option. Both static and shared library options must be enabled for courier-authlib to build properly (but see "Post-installation cleanup" below).

#### `--without-stdheaderdir`

The default configuration installs development files in `/usr/local/include` (see "What gets installed", below). This directory is usually in the compiler's search path for header files. This option must be specified if the compiler does NOT search for header files in `/usr/local/include` by default.

This option must also be specified if other configuration options (such as `--prefix` or `--includedir`) specify a different installation directory, and the new directory is also not searched by the compiler, by default

#### `--with-mailuser=userid, --with-mailgroup=groupid`

"userid" is a reserved system username, "groupid" is a reserved system groupname. These two options should be used before installing Courier for the first time. These options are not required before installing Courier-IMAP or SqWebMail.

These options specify the user/group that will own the configuration files, and the socket that authentication daemon process listens on. This is a key part of Courier's security model.

These options should not be necessary if upgrading from an earlier version of Courier and/or this authentication library. The default userid and groupid are computed as follows:

- If an earlier version of the Courier authentication library is already installed in the same directory, the userid and the groupid is the same as the earlier version, otherwise:
- The userid is the first userid from the following list which exists in the system: courier, daemon, adm, bin, root; and the groupid is the first groupid from the following list which exists in the system: courier, daemon, adm, sys, root.

When installing Courier authentication library for the first time, it is highly recommended to create a "courier" userid and groupid, so that specifying these options will not be necessary.

#### `VARIABLE=``value`

Environment variables may be set either before running the configure script, or by providing the environment variables as parameters to the configure script. Example:

>     ./configure --with-mailuser=mail --with-mailgroup=mail \
>          CC=gcc-10 CXX=g++-10 LDFLAGS=-L/opt/fsf/lib \
>          MAKE=gmake

The `CC` and `CXX` environment variables specify the C compiler that will be used to compile the authentication library. `LDFLAGS` specifies additiona linker flags, etc...

## Dependencies

On a minimum, bare-bones system, the Courier authentication library builds support for garden-variety authentication against system accounts (from the system's password file, `/etc/passwd`).

If the `configure` script detects that certain optional software components are installed, additional authentication modules will be built and installed. This chapter describes what needs to be installed in order to build the optional authentication modules.

> NOTE: In all cases, it is not sufficient to install the runtime support libraries for the following components. In order to build the authentication modules the DEVELOPMENT LIBRARIES for the following software packages must be installed. The development libraries are usually a separate package, that must be installed in addition to the package that adds alleged support for the following software libraries.

- GDBM or Berkeley DB library - The `userdb` authentication module will be built if either library is installed. The `userdb` authentication module includes Perl scripts that maintain a list of available accounts in plain text files. A Perl script then compiles the account list into a binary database, either GDBM or DB, which is then used to look up account information.
- OpenLDAP - The LDAP authentication modules requires OpenLDAP client libraries to be installed. Sometimes there's some confusion when commercial LDAP servers are used, which come with their own development toolkits, which use a different API than OpenLDAP. Even if a commercial LDAP server is used to provide LDAP services, OpenLDAP is still required to enable LDAP services in Courier.
- MySQL, PostgreSQL, and SQLite - The MySQL, PostgreSQL, and SQLite authentication modules require, obviously, MySQL/PostgreSQL/SQLite development libraries.

## What gets installed

- `/usr/local/etc/authlib` - the configuration files.
- `/usr/local/sbin` - the authdaemond startup script; several utility programs (courierlogger, authconfig, authtest, authenumerate); and userdb scripts.
- `/usr/local/lib/courier-authlib` - various authentication modules, as shared libraries.
- `/usr/local/libexec/courier-authlib` - some miscellaneous stuff.
- `/usr/local/var/authdaemon` - a subdirectory that contains the filesystem socket which authdaemond listens on.
- `/usr/local/include` - a header file that Courier packages will use to build against courier-authlib.

Toolchain options to the `configure` script may be used to select alternative installation directories for these components.

### Post-installation cleanup

On most systems, after running `make install-configure` all static libraries can be removed from the `/usr/local/lib/courier-authlib` directory:

`rm -rf /usr/local/lib/courier-authlib/*.a`

The Courier authentication library uses only the shared libraries. The static versions of the shared libraries are not used. They are installed by default, via libtool, but are not really needed. On most platforms the libtool files, "*.la" can also be removed. Do not remove any soft links.

## For more information

Following "`make install`", see the `README_authlib.html` file for details on setting up the authentication modules. The `README_authlib.html` file gets assembled as part of the build process.

Before proceding to install any other packages, be sure to verify that the authentication library is working by running the `authtest` command, as documented in the `README_authlib.html` file.

## Starting and stopping the authentication daemon

Arrangements must be made to run the `courier-authlib.sysvinit` script with "start" and "stop" parameters at system startup and shutdown. `make install` does not install this script from the source directory, it needs to be installed manually.

## Guidelines for using other package managers

The recommended way to build packages can be inferred from the RPM build script. It is summarized here for convenience:

- Decide whether or not Courier-specific userid and groupid needs to be created, and, if so, make the necessary arrangements.
- Ensure that all prerequisite development libraries are available.
- Run the `configure` script, run `make`, then `make install` as usual.
- Copy the "`sysconftool`" script somewhere into the installation tree. A good place would be `%libexecdir%/courier-authlib`. This is the '`make install-upgrade`' command. Don't run this at build time. Instead, arrange for the package installation script to run the "`sysconftool %sysconfdir%/authlib/*.dist`" after the package is installed OR UPGRADED.
- The "`authdaemond`", "`authenumerate`", and "`authtest`" commands can be renamed, to avoid name clashes.
- There are two types of libraries that get installed in `%libdir%`:
  1. Common libraries that application link with, `libcourier*`.
  2. Dynamically-loaded authentication modules: `libauth*`.

  Remove all static libraries from `%libdir%/courier-authlib`. Keep the `*.la` and `*.so` for `libcourier*`, and include them in a devel subpackage. Remove `*.la` and `*.so` for all `libauth*` libraries, they are not needed.

Now, create the installable packages, as follows:

- `%libdir%/courier-authlib/libauthldap*` goes into the LDAP subpackage.
- `%libdir%/courier-authlib/libauthmysql*` goes into the MySQL subpackage.
- `%libdir%/courier-authlib/libauthsqlite*` goes into the SQLite subpackage.
- `%libdir%/courier-authlib/libauthpgsql*` goes into the PostgreSQL subpackage.
- `%libdir%/courier-authlib/libauthuserdb*` goes into the userdb subpackage.
- Everything else can go into the main package. Optionally, the `courierauthconfig` binary, stuff in `%includedir%`, and in `%mandir%/man3`, can go into a devel subpackage.