Add known_hosts post and related scripts.

[blog.git] / posts / Monkeysphere / unhash-known-hosts.sh

diff --git a/posts/Monkeysphere/unhash-known-hosts.sh b/posts/Monkeysphere/unhash-known-hosts.sh
new file mode 100755 (executable)
index 0000000..b4654a6
--- /dev/null
+++ b/posts/Monkeysphere/unhash-known-hosts.sh
@@ -0,0 +1,60 @@
+#!/bin/bash
+#
+# Copyright (C) 2011 W. Trevor King <wking@drexel.edu>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License as
+# published by the Free Software Foundation, either version 3 of the
+# License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this program.  If not, see
+# <http://www.gnu.org/licenses/>.
+
+# Use Monkeysphere IDs in your GnuPG keyring to identify entries in
+# your known_hosts file.
+#
+# usage: unhash-known-hosts.sh path/to/known_hosts
+
+KNOWN_HOSTS="~/.ssh/known_hosts"
+if [ -n "${1}" ]; then
+               KNOWN_HOSTS="${1}"
+fi
+
+GPG_IDS=$(gpg --list-keys ssh | grep pub | sed 's/^[^/]*\///' | sed 's/ .*//')
+if [ -z "${GPG_IDS}" ]; then
+               echo 'no SSH IDs found in GnuPG keyring'
+               exit 1
+fi
+
+declare -A GPG_KEY
+declare -A GPG_UID
+
+for GPG_ID in $GPG_IDS; do
+    GPG_ENTRY=$(gpg --export "${GPG_ID}" | openpgp2ssh)
+               GPG_KEY["${GPG_ENTRY}"]="${GPG_ID}"
+               GPG_UID["${GPG_ID}"]=$(gpg --list-keys "${GPG_ID}" | sed -n 's/^uid *//p')
+done
+
+while read ENTRY; do
+    if [ -n "${ENTRY}" ] && [ "${ENTRY:0:1}" == "|" ]; then
+                               HASH=$(echo "${ENTRY}" | awk '{print $1}')
+                               ALG=$(echo "${ENTRY}" | awk '{print $2}')
+                               KEY=$(echo "${ENTRY}" | awk '{print $3}')
+                               #echo "${ENTRY}"
+                               #echo "ALG: ${ALG}"
+                               #echo "KEY: ${KEY}"
+                               ALG_KEY="${ALG} ${KEY}"
+                               GPG_ID="${GPG_KEY[${ALG_KEY}]}"
+                               if [ -n "${GPG_ID}" ]; then
+                                               echo "GnuPG ID ${GPG_ID} (${GPG_UID[$GPG_ID]}) matches ${HASH}"
+                               else
+                                               echo "did not match ${HASH}"
+                               fi
+               fi
+done < "${KNOWN_HOSTS}"