Pre-built binaries
==================
Docker images of `master` and of the tagged versions are
available directly from [Github](https://github.com/yrutschle/sslh/pkgs/container/sslh).
Windows binaries for Cygwin are graciously produced by
nono303 on his [repository](https://github.com/nono303/sslh).
Compile and install
===================
Dependencies
------------
`sslh` uses:
* [libconfig](http://www.hyperrealm.com/libconfig/). For
Debian this is contained in package `libconfig-dev`. You
can compile with or without it using USELIBCONFIG in the
Makefile.
* [libwrap](http://packages.debian.org/source/unstable/tcp-wrappers).
For Debian, this is contained in packages
`libwrap0-dev`. You
can compile with or without it using USELIBWRAP in the
Makefile.
* [libsystemd](http://packages.debian.org/source/unstable/libsystemd-dev), in package `libsystemd-dev`. You
can compile with or without it using USESYSTEMD in the
Makefile.
* [libcap](http://packages.debian.org/source/unstable/libcap-dev), in package `libcap-dev`. You can compile with or without it using USELIBCAP in the Makefile
* libbsd, to enable to change the process name (as shown in
`ps`, so each forked process shows what protocol and what
connection it is serving),
which requires `libbsd` at runtime, and `libbsd-dev` at
compile-time.
* libpcre2, in package `libpcre-dev`. You can compile
with or without it using ENABLE_REGEX in the Makefile.
* libev-dev, in package `libev-dev`. If you build a binary
specifically and do not build `sslh-ev`, you don't need
this.
For OpenSUSE, these are contained in packages libconfig9 and
libconfig-dev in repository
For Fedora, you'll need packages `libconfig` and
`libconfig-devel`:
yum install libconfig libconfig-devel
If you want to rebuild `sslh-conf.c` (after a `make
distclean` for example), you will also need to add
[conf2struct](https://www.rutschle.net/tech/conf2struct/README.html)
(v1.5) to your path.
The test scripts are written in Perl, and will require
IO::Socket::INET6 (libio-socket-inet6-perl in Debian).
Compilation
-----------
After this, the Makefile should work:
make install
There are a couple of configuration options at the beginning
of the Makefile:
* `USELIBWRAP` compiles support for host access control (see
`hosts_access(3)`), you will need `libwrap` headers and
library to compile (`libwrap0-dev` in Debian).
* `USELIBCONFIG` compiles support for the configuration
file. You will need `libconfig` headers to compile
(`libconfig8-dev` in Debian).
* `USESYSTEMD` compiles support for using systemd socket activation.
You will need `systemd` headers to compile (`systemd-devel` in Fedora).
* `USELIBBSD` compiles support for updating the process name (as shown
by `ps`).
Generating the configuration parser
-----------------------------------
The configuration file and command line parser is generated
by `conf2struct`, from `sslhconf.cfg`, which generates
`sslh-conf.c` and `sslh-conf.h`. The resulting files are
included in the source so `sslh` can be built without
`conf2struct` installed.
Further, to prevent build issues, `sslh-conf.[ch]` has no
dependency to `sslhconf.cfg` in the Makefile. In the event
of adding configuration settings, they need to be
regenerated using `make c2s`.
Binaries
--------
The Makefile produces three different executables: `sslh-fork`,
`sslh-select` and `sslh-ev`:
* `sslh-fork` forks a new process for each incoming connection.
It is well-tested and very reliable, but incurs the overhead
of many processes.
If you are going to use `sslh` for a "small" setup (less than
a dozen ssh connections and a low-traffic https server) then
`sslh-fork` is probably more suited for you.
* `sslh-select` uses only one thread, which monitors all
connections at once. It only incurs a 16 byte overhead per
connection. Also, if it stops, you'll lose all connections,
which means you can't upgrade it remotely. If you are going
to use `sslh` on a "medium" setup (a few hundreds of
connections), or if you are on a system where forking is
expensive (e.g. Windows), `sslh-select` will be better.
* `sslh-ev` is similar to `sslh-select`, but uses `libev` as
a backend. This allows using specific kernel APIs that
allow to manage thousands of connections concurrently.
Installation
------------
* In general:
make
cp sslh-fork /usr/local/sbin/sslh
cp basic.cfg /etc/sslh.cfg
vi /etc/sslh.cfg
* For Debian:
cp scripts/etc.init.d.sslh /etc/init.d/sslh
* For CentOS:
cp scripts/etc.rc.d.init.d.sslh.centos /etc/rc.d/init.d/sslh
You might need to create links in /etc/rc.d so that the server
start automatically at boot-up, e.g. under Debian:
update-rc.d sslh defaults