Closes #6 by adding support for ssh-keyscan(1) to the add-host-key co…

…mmand.
rerun-modules · Dec 4, 2012 · f1dbe3f · f1dbe3f
1 parent bfbca21
commit f1dbe3f
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Showing 6 changed files with 61 additions and 18 deletions.
diff --git a/commands/add-host-key/metadata b/commands/add-host-key/metadata
@@ -3,4 +3,4 @@
 # Sun Nov 18 08:46:36 PST 2012
 NAME=add-host-key
 DESCRIPTION="Adds a public key to the specified known hosts file"
-OPTIONS="hostname public-key type known-hosts-file"
+OPTIONS="hostname type known-hosts-file host-key"
diff --git a/commands/add-host-key/options.sh b/commands/add-host-key/options.sh
@@ -1,7 +1,7 @@
 # Generated by stubbs:add-option. Do not edit, if using stubbs.
-# Created: Sun Nov 18 09:05:34 PST 2012
+# Created: Mon Dec  3 15:36:32 PST 2012
 #
-#/ usage: ssh:add-host-key  --hostname <>  --public-key <> [ --type <dsa>] [ --known-hosts-file <$HOME/.ssh/known_hosts>] 
+#/ usage: ssh:add-host-key  --hostname <> [ --type <dsa>] [ --known-hosts-file <$HOME/.ssh/known_hosts>] [ --host-key <>] 
 
 # _rerun_options_parse_ - Parse the command arguments and set option variables.
 #
@@ -23,9 +23,9 @@ rerun_options_parse() {
         OPT="$1"
         case "$OPT" in
             --hostname) rerun_option_check $# ; HOSTNAME=$2 ; shift ;;
-            --public-key) rerun_option_check $# ; PUBLIC_KEY=$2 ; shift ;;
             --type) rerun_option_check $# ; TYPE=$2 ; shift ;;
             --known-hosts-file) rerun_option_check $# ; KNOWN_HOSTS_FILE=$2 ; shift ;;
+            --host-key) rerun_option_check $# ; HOST_KEY=$2 ; shift ;;
             # help option
             -?)
                 rerun_option_usage
@@ -43,7 +43,6 @@ rerun_options_parse() {
     [ -z "$KNOWN_HOSTS_FILE" ] && KNOWN_HOSTS_FILE="$HOME/.ssh/known_hosts"
     # Check required options are set
     [ -z "$HOSTNAME" ] && { echo >&2 "missing required option: --hostname" ; return 2 ; }
-    [ -z "$PUBLIC_KEY" ] && { echo >&2 "missing required option: --public-key" ; return 2 ; }
     # If option variables are declared exportable, export them.
 
     #
@@ -53,8 +52,8 @@ rerun_options_parse() {
 
 # Initialize the options variables to null.
 HOSTNAME=
-PUBLIC_KEY=
 TYPE=
 KNOWN_HOSTS_FILE=
+HOST_KEY=
 
 
diff --git a/commands/add-host-key/script b/commands/add-host-key/script
@@ -10,7 +10,7 @@
 # and show its options.
 # 
 #/ command: ssh:add-host-key: "Adds a public key to the specified known hosts file"
-#/ usage: rerun ssh:add-host-key  --hostname <>  --public-key <> [ --type <dsa>] [ --known-hosts-file <$HOME/.ssh/known_hosts>] 
+#/ usage: rerun ssh:add-host-key  --hostname <> [ --type <dsa>] [ --known-hosts-file <$HOME/.ssh/known_hosts>] [ --host-key <>] 
 
 # Load common functions
 # ---------------------
@@ -47,7 +47,7 @@ set -o nounset -o pipefail
 # declared by `rerun` or by the option parser function.
 
 #/ rerun-variables: RERUN, RERUN_VERSION, RERUN_MODULES, RERUN_MODULE_DIR
-#/ option-variables: HOSTNAME PUBLIC_KEY TYPE KNOWN_HOSTS_FILE
+#/ option-variables: HOSTNAME TYPE KNOWN_HOSTS_FILE HOST_KEY
 
 # The `rerun_options_parse` function processes the command line
 # arguments. Each accepted command line flag results in setting 
@@ -63,18 +63,24 @@ rerun_options_parse "$@"
 # Put the command implementation here.
 # - - -
 
+# If the host key was not provided on the command line use ssh-keyscan(1) to acquire it.
+if [[ -z $HOST_KEY ]]
+then
+  HOST_KEY=$(ssh-keyscan -t ${TYPE} ${HOSTNAME} 2>/dev/null | cut -d' ' -f3)
+fi
+
 if [[ -r ${KNOWN_HOSTS_FILE} ]]
 then
   # Eliminate other entries for this key, if they are not identical to the one specified.
 
-  if grep -q "^${HOSTNAME} ssh-${TYPE} ${PUBLIC_KEY}$" ${KNOWN_HOSTS_FILE}
+  if grep -q "^${HOSTNAME} ssh-${TYPE} ${HOST_KEY}$" ${KNOWN_HOSTS_FILE}
   then
     echo "INFO: entry already exists, skipping" 1>&2
   else
     TMP_KNOWN_HOSTS_FILE=$(mktemp)
 
     # Ignore the exit code since it's an indeterminate indication of success in this case.
-    if fgrep -v "${PUBLIC_KEY}" ${KNOWN_HOSTS_FILE} > ${TMP_KNOWN_HOSTS_FILE}
+    if fgrep -v "${HOST_KEY}" ${KNOWN_HOSTS_FILE} > ${TMP_KNOWN_HOSTS_FILE}
     then
       :
     fi
@@ -88,7 +94,7 @@ then
     rm -f ${TMP_KNOWN_HOSTS_FILE}
 
     # Compose and append the entry to the specified known hosts file.
-    echo "${HOSTNAME} ssh-${TYPE} ${PUBLIC_KEY}" >> ${KNOWN_HOSTS_FILE}
+    echo "${HOSTNAME} ssh-${TYPE} ${HOST_KEY}" >> ${KNOWN_HOSTS_FILE}
 
     echo "INFO: replaced existing entrie(s)" 1>&2
   fi
@@ -97,7 +103,7 @@ else
   [[ -d $(dirname ${KNOWN_HOSTS_FILE}) ]] || mkdir $(dirname ${KNOWN_HOSTS_FILE}) && chmod 700 $(dirname ${KNOWN_HOSTS_FILE})
 
   # Create the known hosts file with default permissions, if it doesn't already exist.
-  echo "${HOSTNAME} ssh-${TYPE} ${PUBLIC_KEY}" > ${KNOWN_HOSTS_FILE} 
+  echo "${HOSTNAME} ssh-${TYPE} ${HOST_KEY}" > ${KNOWN_HOSTS_FILE} 
 
   echo "INFO: added entry to new known hosts file" 1>&2
 fi

diff --git a/metadata b/metadata
@@ -3,7 +3,7 @@
 NAME=ssh
 DESCRIPTION="Rerun module for managing secure shell client and server usage"
 INTERPRETER="bash"
-VERSION=1.0.1
+VERSION=1.1.1
 REQUIRES=
 EXTERNALS=
 META_MODULE=
diff --git a/options/host-key/metadata b/options/host-key/metadata
@@ -0,0 +1,12 @@
+# option metadata
+# generated by stubbs:add-option
+# Mon Dec  3 15:36:04 PST 2012
+NAME=host-key
+DESCRIPTION="Public key of the specified host"
+ARGUMENTS=true
+REQUIRED=false
+SHORT=
+LONG=host-key
+DEFAULT=
+EXPORT=false
+
diff --git a/tests/add-host-key-1-test.sh b/tests/add-host-key-1-test.sh
@@ -14,31 +14,57 @@
 
 describe "add-host-key"
 
-it_works_with_a_new_key_and_a_duplicate() {
+# Tests generating a DSA public host key and adding it to a temporary known hosts file.
+it_works_with_a_new_and_duplicate_key() {
   # Generate a new key-pair into a temporary directory.
   TMPDIR=$(mktemp -d)
   rerun ssh:keygen --key-file ${TMPDIR}/id_dsa
 
   # Get the fields from the generated public key file.
   TYPE=$(cut -d' ' -f1 < ${TMPDIR}/id_dsa.pub | cut -d- -f2)
   PUBLIC_KEY=$(cut -d' ' -f2 < ${TMPDIR}/id_dsa.pub)
-  COMMENT=$(cut -d' ' -f3- < ${TMPDIR}/id_dsa.pub)
 
   # Add the key to a new empty known hosts file and make sure its the same as the original public key:
-  rerun ssh:add-host-key --public-key "${PUBLIC_KEY}" --known-hosts-file ${TMPDIR}/.ssh/known_hosts --type ${TYPE} --hostname localhost
+  rerun ssh:add-host-key --host-key "${PUBLIC_KEY}" --known-hosts-file ${TMPDIR}/.ssh/known_hosts --type ${TYPE} --hostname localhost
   echo "localhost ssh-${TYPE} ${PUBLIC_KEY}" > ${TMPDIR}/known_hosts.test
   diff ${TMPDIR}/known_hosts.test ${TMPDIR}/.ssh/known_hosts
 
   # Add the key a second time and make sure its the same as the original public key thus proving a duplicate entry was avoided:
-  rerun ssh:add-host-key --public-key "${PUBLIC_KEY}" --known-hosts-file ${TMPDIR}/.ssh/known_hosts --type ${TYPE} --hostname localhost
+  rerun ssh:add-host-key --host-key "${PUBLIC_KEY}" --known-hosts-file ${TMPDIR}/.ssh/known_hosts --type ${TYPE} --hostname localhost
   echo "localhost ssh-${TYPE} ${PUBLIC_KEY}" > ${TMPDIR}/known_hosts.test
   diff ${TMPDIR}/known_hosts.test ${TMPDIR}/.ssh/known_hosts
 
   # Add the key a third time with a different hostname proving the existing entry is replaced:
-  rerun ssh:add-host-key --public-key "${PUBLIC_KEY}" --known-hosts-file ${TMPDIR}/.ssh/known_hosts --type ${TYPE} --hostname $HOSTNAME
+  rerun ssh:add-host-key --host-key "${PUBLIC_KEY}" --known-hosts-file ${TMPDIR}/.ssh/known_hosts --type ${TYPE} --hostname $HOSTNAME
   echo "$HOSTNAME ssh-${TYPE} ${PUBLIC_KEY}" > ${TMPDIR}/known_hosts.test
   diff ${TMPDIR}/known_hosts.test ${TMPDIR}/.ssh/known_hosts
 
   rm -rf ${TMPDIR}
 }
 
+# Tests using ssh-keyscan(1) to get the localhost's DSA public host key and add it to a temporary known hosts file
+it_works_when_no_host_key_is_provided() {
+  # Generate a new key-pair into a temporary directory.
+  TMPDIR=$(mktemp -d)
+
+  # Get the fields from the generated public key file.
+  TYPE=dsa
+  PUBLIC_KEY=$(ssh-keyscan -t dsa localhost 2>/dev/null | cut  -d' ' -f3)
+
+  # Add the key to a new empty known hosts file and make sure its the same as the original public key:
+  rerun ssh:add-host-key --known-hosts-file ${TMPDIR}/.ssh/known_hosts --type ${TYPE} --hostname localhost
+  echo "localhost ssh-${TYPE} ${PUBLIC_KEY}" > ${TMPDIR}/known_hosts.test
+  diff ${TMPDIR}/known_hosts.test ${TMPDIR}/.ssh/known_hosts
+
+  # Add the key a second time and make sure its the same as the original public key thus proving a duplicate entry was avoided:
+  rerun ssh:add-host-key --known-hosts-file ${TMPDIR}/.ssh/known_hosts --type ${TYPE} --hostname localhost
+  echo "localhost ssh-${TYPE} ${PUBLIC_KEY}" > ${TMPDIR}/known_hosts.test
+  diff ${TMPDIR}/known_hosts.test ${TMPDIR}/.ssh/known_hosts
+
+  # Add the key a third time with a different hostname proving the existing entry is replaced:
+  rerun ssh:add-host-key --known-hosts-file ${TMPDIR}/.ssh/known_hosts --type ${TYPE} --hostname $HOSTNAME
+  echo "$HOSTNAME ssh-${TYPE} ${PUBLIC_KEY}" > ${TMPDIR}/known_hosts.test
+  diff ${TMPDIR}/known_hosts.test ${TMPDIR}/.ssh/known_hosts
+
+  rm -rf ${TMPDIR}
+}