Drop ssh-vulnkey

Drop ssh-vulnkey and the associated ssh/ssh-add/sshd integration
code, leaving only basic configuration file compatibility, since it
has been nearly six years since the original vulnerability and this
code is not likely to be of much value any more.  See
https://lists.debian.org/debian-devel/2013/09/msg00240.html for my
full reasoning.

1 files changed, 0 insertions, 242 deletions

diff --git a/ssh-vulnkey.1 b/ssh-vulnkey.1
deleted file mode 100644
index bcb9d31c6..000000000
--- a/ssh-vulnkey.1
+++ /dev/null
@@ -1,242 +0,0 @@
-.\" Copyright (c) 2008 Canonical Ltd.  All rights reserved.
-.\"
-.\" Redistribution and use in source and binary forms, with or without
-.\" modification, are permitted provided that the following conditions
-.\" are met:
-.\" 1. Redistributions of source code must retain the above copyright
-.\"    notice, this list of conditions and the following disclaimer.
-.\" 2. Redistributions in binary form must reproduce the above copyright
-.\"    notice, this list of conditions and the following disclaimer in the
-.\"    documentation and/or other materials provided with the distribution.
-.\"
-.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
-.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
-.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
-.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
-.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
-.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
-.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-.\"
-.Dd $Mdocdate: May 12 2008 $
-.Dt SSH-VULNKEY 1
-.Os
-.Sh NAME
-.Nm ssh-vulnkey
-.Nd check blacklist of compromised keys
-.Sh SYNOPSIS
-.Nm
-.Op Fl q | Fl v
-.Ar file ...
-.Nm
-.Fl a
-.Sh DESCRIPTION
-.Nm
-checks a key against a blacklist of compromised keys.
-.Pp
-A substantial number of keys are known to have been generated using a broken
-version of OpenSSL distributed by Debian which failed to seed its random
-number generator correctly.
-Keys generated using these OpenSSL versions should be assumed to be
-compromised.
-This tool may be useful in checking for such keys.
-.Pp
-Keys that are compromised cannot be repaired; replacements must be generated
-using
-.Xr ssh-keygen 1 .
-Make sure to update
-.Pa authorized_keys
-files on all systems where compromised keys were permitted to authenticate.
-.Pp
-The argument list will be interpreted as a list of paths to public key files
-or
-.Pa authorized_keys
-files.
-If no suitable file is found at a given path,
-.Nm
-will append
-.Pa .pub
-and retry, in case it was given a private key file.
-If no files are given as arguments,
-.Nm
-will check
-.Pa ~/.ssh/id_rsa ,
-.Pa ~/.ssh/id_dsa ,
-.Pa ~/.ssh/identity ,
-.Pa ~/.ssh/authorized_keys
-and
-.Pa ~/.ssh/authorized_keys2 ,
-as well as the system's host keys if readable.
-.Pp
-If
-.Dq -
-is given as an argument,
-.Nm
-will read from standard input.
-This can be used to process output from
-.Xr ssh-keyscan 1 ,
-for example:
-.Pp
-.Dl $ ssh-keyscan -t rsa remote.example.org | ssh-vulnkey -
-.Pp
-Unless the
-.Cm PermitBlacklistedKeys
-option is used,
-.Xr sshd 8
-will reject attempts to authenticate with keys in the compromised list.
-.Pp
-The output from
-.Nm
-looks like this:
-.Pp
-.Bd -literal -offset indent
-/etc/ssh/ssh_host_key:1: COMPROMISED: RSA1 2048 xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx root@host
-/home/user/.ssh/id_dsa:1: Not blacklisted: DSA 1024 xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx /home/user/.ssh/id_dsa.pub
-/home/user/.ssh/authorized_keys:3: Unknown (blacklist file not installed): RSA 1024 xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx user@host
-.Ed
-.Pp
-Each line is of the following format (any lines beginning with
-.Dq #
-should be ignored by scripts):
-.Pp
-.Dl Ar filename : Ns Ar line : Ar status : Ar type Ar size Ar fingerprint Ar comment
-.Pp
-It is important to distinguish between the possible values of
-.Ar status :
-.Pp
-.Bl -tag -width Ds
-.It COMPROMISED
-These keys are listed in a blacklist file, normally because their
-corresponding private keys are well-known.
-Replacements must be generated using
-.Xr ssh-keygen 1 .
-.It Not blacklisted
-A blacklist file exists for this key type and size, but this key is not
-listed in it.
-Unless there is some particular reason to believe otherwise, this key
-may be used safely.
-(Note that DSA keys used with the broken version of OpenSSL distributed
-by Debian may be compromised in the event that anyone captured a network
-trace, even if they were generated with a secure version of OpenSSL.)
-.It Unknown (blacklist file not installed)
-No blacklist file exists for this key type and size.
-You should find a suitable published blacklist and install it before
-deciding whether this key is safe to use.
-.El
-.Pp
-The options are as follows:
-.Bl -tag -width Ds
-.It Fl a
-Check keys of all users on the system.
-You will typically need to run
-.Nm
-as root to use this option.
-For each user,
-.Nm
-will check
-.Pa ~/.ssh/id_rsa ,
-.Pa ~/.ssh/id_dsa ,
-.Pa ~/.ssh/identity ,
-.Pa ~/.ssh/authorized_keys
-and
-.Pa ~/.ssh/authorized_keys2 .
-It will also check the system's host keys.
-.It Fl q
-Quiet mode.
-Normally,
-.Nm
-outputs the fingerprint of each key scanned, with a description of its
-status.
-This option suppresses that output.
-.It Fl v
-Verbose mode.
-Normally,
-.Nm
-does not output anything for keys that are not listed in their corresponding
-blacklist file (although it still produces output for keys for which there
-is no blacklist file, since their status is unknown).
-This option causes
-.Nm
-to produce output for all keys.
-.El
-.Sh EXIT STATUS
-.Nm
-will exit zero if any of the given keys were in the compromised list,
-otherwise non-zero.
-.Sh BLACKLIST FILE FORMAT
-The blacklist file may start with comments, on lines starting with
-.Dq # .
-After these initial comments, it must follow a strict format:
-.Pp
-.Bl -bullet -offset indent -compact
-.It
-All the lines must be exactly the same length (20 characters followed by a
-newline) and must be in sorted order.
-.It
-Each line must consist of the lower-case hexadecimal MD5 key fingerprint,
-without colons, and with the first 12 characters removed (that is, the least
-significant 80 bits of the fingerprint).
-.El
-.Pp
-The key fingerprint may be generated using
-.Xr ssh-keygen 1 :
-.Pp
-.Dl $ ssh-keygen -l -f /path/to/key
-.Pp
-This strict format is necessary to allow the blacklist file to be checked
-quickly, using a binary-search algorithm.
-.Sh FILES
-.Bl -tag -width Ds
-.It Pa ~/.ssh/id_rsa
-If present, contains the protocol version 2 RSA authentication identity of
-the user.
-.It Pa ~/.ssh/id_dsa
-If present, contains the protocol version 2 DSA authentication identity of
-the user.
-.It Pa ~/.ssh/identity
-If present, contains the protocol version 1 RSA authentication identity of
-the user.
-.It Pa ~/.ssh/authorized_keys
-If present, lists the public keys (RSA/DSA) that can be used for logging in
-as this user.
-.It Pa ~/.ssh/authorized_keys2
-Obsolete name for
-.Pa ~/.ssh/authorized_keys .
-This file may still be present on some old systems, but should not be
-created if it is missing.
-.It Pa /etc/ssh/ssh_host_rsa_key
-If present, contains the protocol version 2 RSA identity of the system.
-.It Pa /etc/ssh/ssh_host_dsa_key
-If present, contains the protocol version 2 DSA identity of the system.
-.It Pa /etc/ssh/ssh_host_key
-If present, contains the protocol version 1 RSA identity of the system.
-.It Pa /usr/share/ssh/blacklist. Ns Ar TYPE Ns Pa - Ns Ar LENGTH
-If present, lists the blacklisted keys of type
-.Ar TYPE
-.Pf ( Dq RSA
-or
-.Dq DSA )
-and bit length
-.Ar LENGTH .
-The format of this file is described above.
-RSA1 keys are converted to RSA before being checked in the blacklist.
-Note that the fingerprints of RSA1 keys are computed differently, so you
-will not be able to find them in the blacklist by hand.
-.It Pa /etc/ssh/blacklist. Ns Ar TYPE Ns Pa - Ns Ar LENGTH
-Same as
-.Pa /usr/share/ssh/blacklist. Ns Ar TYPE Ns Pa - Ns Ar LENGTH ,
-but may be edited by the system administrator to add new blacklist entries.
-.El
-.Sh SEE ALSO
-.Xr ssh-keygen 1 ,
-.Xr sshd 8
-.Sh AUTHORS
-.An -nosplit
-.An Colin Watson Aq cjwatson@ubuntu.com
-.Pp
-Florian Weimer suggested the option to check keys of all users, and the idea
-of processing
-.Xr ssh-keyscan 1
-output.