Problem:
IPv6 addresses are 4 bytes long and don't fit inside a `sockaddr`, so
`recvfrom` will truncate the address to the first half.
When generating a reply, the remaining half of the address is filled
with garbage and the packet is subsequently delivered to the wrong host,
if not immediately dropped.
Solution:
replace `sockaddr` with `sockaddr_storage`, the latter is guaranteed to
be large enough to hold an IPv6 address and pointers can be cast to
`sockaddr *` when needed.
This allows people to chroot sslh into a path to further harden it.
We have to rework the user logic a bit because we need to look up
the user details *before* we chroot (as we need to read /etc/passwd
files), but do the actual priv dropping *after* we chroot (so we
have permission to make the actual chroot call).
Similarly, we need to open the syslog before we drop privs because
/dev/log won't be available inside the chroot.
When building the source from a checked out tag, eg v1.15, VERSION will
equal v1.15. However, when building from anything other than a tagged
version, you get 'v1.15-4-g50432d5-dirty' meaning I was 4 patches in
front of v1.15, particularly '50432d5' was my current HEAD, and I had
uncommited changes, '-dirty'.
Very useful for folks submitting bug reports on versions they compiled
themselves.
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
Corrected OpenVPN probe to support pre-shared secret
mode (OpenVPN port-sharing code is... wrong). Thanks
to Kai Ellinger for help in investigating and
testing.
Added an actual TLS/SSL probe.
Added configurable --on-timeout protocol
specification.
Added a --anyprot protocol probe (equivalent to what
--ssl was).
Makefile respects the user's compiler and CFLAG
choices (falling back to the current values if
undefined), as well as LDFLAGS.
(Michael Palimaka)
Added "After" and "KillMode" to systemd.sslh.service
(Thomas Weischuh).
Added LSB tags to etc.init.d.sslh
(Thomas Varis).
Added support for configuration file.
New protocol probes can be defined using regular
expressions that match the first packet sent by the
client.
sslh now connects timed out connections to the first
configured protocol instead of 'ssh' (just make sure
ssh is the first defined protocol).
sslh now tries protocols in the order in which they
are defined (just make sure sslh is the last defined
protocol).