#!/bin/sh
# Nitin Jerath - Aug 2005
#Usage sshUserSetup.sh  -user <user name> [ -hosts \"<space separated hostlist>\" | -hostfile <absolute path of cluster configuration file> ] [ -advanced ]  [ -verify] [ -exverify ] [ -logfile <desired absolute path of logfile> ] [-confirm] [-shared] [-help] [-usePassphrase] [-noPromptPassphrase]
#eg. sshUserSetup.sh -hosts "host1 host2" -user njerath -advanced
#This script is used to setup SSH connectivity from the host on which it is
# run to the specified remote hosts. After this script is run, the user can use # SSH to run commands on the remote hosts or copy files between the local host
# and the remote hosts without being prompted for passwords or confirmations.
# The list of remote hosts and the user name on the remote host is specified as 
# a command line parameter to the script. Note that in case the user on the 
# remote host has its home directory NFS mounted or shared across the remote 
# hosts, this script should be used with -shared option. 
#Specifying the -advanced option on the command line would result in SSH 
# connectivity being setup among the remote hosts which means that SSH can be 
# used to run commands on one remote host from the other remote host or copy 
# files between the remote hosts without being prompted for passwords or 
# confirmations.
#Please note that the script would remove write permissions on the remote hosts
#for the user home directory and ~/.ssh directory for "group" and "others". This
# is an SSH requirement. The user would be explicitly informed about this by the script and prompted to continue. In case the user presses no, the script would exit. In case the user does not want to be prompted, he can use -confirm option.
# As a part of the setup, the script would use SSH to create files within ~/.ssh
# directory of the remote node and to setup the requisite permissions. The 
#script also uses SCP to copy the local host public key to the remote hosts so
# that the remote hosts trust the local host for SSH. At the time, the script 
#performs these steps, SSH connectivity has not been completely setup  hence
# the script would prompt the user for the remote host password. 
#For each remote host, for remote users with non-shared homes this would be 
# done once for SSH and  once for SCP. If the number of remote hosts are x, the 
# user would be prompted  2x times for passwords. For remote users with shared 
# homes, the user would be prompted only twice, once each for SCP and SSH.
#For security reasons, the script does not save passwords and reuse it. Also, 
# for security reasons, the script does not accept passwords redirected from a 
#file. The user has to key in the confirmations and passwords at the prompts.
#The -verify option means that the user just wants to verify whether SSH has 
#been set up. In this case, the script would not setup SSH but would only check
# whether SSH connectivity has been setup from the local host to the remote 
# hosts. The script would run the date command on each remote host using SSH. In
# case the user is prompted for a password or sees a warning message for a 
#particular host, it means SSH connectivity has not been setup correctly for
# that host.
#In case the -verify option is not specified, the script would setup SSH and 
#then do the verification as well.
#In case the user speciies the -exverify option, an exhaustive verification would be done. In that case, the following would be checked:
# 1. SSH connectivity from local host to all remote hosts.
# 2. SSH connectivity from each remote host to itself and other remote hosts.

#echo Parsing command line arguments
numargs=$#

ADVANCED=false
HOSTNAME=`hostname`
CONFIRM=no
SHARED=false
i=1
USR=$USER

if  test -z "$TEMP"
then
  TEMP=/tmp
fi

IDENTITY=id_rsa
LOGFILE=$TEMP/sshUserSetup_`date +%F-%H-%M-%S`.log
VERIFY=false
EXHAUSTIVE_VERIFY=false
HELP=false
PASSPHRASE=no
RERUN_SSHKEYGEN=no
NO_PROMPT_PASSPHRASE=no

while [ $i -le $numargs ]
do
  j=$1 
  if [ $j = "-hosts" ] 
  then
     HOSTS=$2
     shift 1
     i=`expr $i + 1`
  fi
  if [ $j = "-user" ] 
  then
     USR=$2
     shift 1
     i=`expr $i + 1`
   fi
  if [ $j = "-logfile" ] 
  then
     LOGFILE=$2
     shift 1
     i=`expr $i + 1`
   fi
  if [ $j = "-confirm" ] 
  then
     CONFIRM=yes
   fi
  if [ $j = "-hostfile" ] 
  then
     CLUSTER_CONFIGURATION_FILE=$2
     shift 1
     i=`expr $i + 1`
   fi
  if [ $j = "-usePassphrase" ] 
  then
     PASSPHRASE=yes
   fi
  if [ $j = "-noPromptPassphrase" ] 
  then
     NO_PROMPT_PASSPHRASE=yes
   fi
  if [ $j = "-shared" ] 
  then
     SHARED=true
   fi
  if [ $j = "-exverify" ] 
  then
     EXHAUSTIVE_VERIFY=true
   fi
  if [ $j = "-verify" ] 
  then
     VERIFY=true
   fi
  if [ $j = "-advanced" ] 
  then
     ADVANCED=true
   fi
  if [ $j = "-help" ] 
  then
     HELP=true
   fi
  i=`expr $i + 1`
  shift 1
done


if [ $HELP = "true" ]
then
  echo "Usage $0 -user <user name> [ -hosts \"<space separated hostlist>\" | -hostfile <absolute path of cluster configuration file> ] [ -advanced ]  [ -verify] [ -exverify ] [ -logfile <desired absolute path of logfile> ] [-confirm] [-shared] [-help] [-usePassphrase] [-noPromptPassphrase]"
echo "This script is used to setup SSH connectivity from the host on which it is run to the specified remote hosts. After this script is run, the user can use  SSH to run commands on the remote hosts or copy files between the local host and the remote hosts without being prompted for passwords or confirmations.  The list of remote hosts and the user name on the remote host is specified as a command line parameter to the script. "
echo "-user : User on remote hosts. " 
echo "-hosts : Space separated remote hosts list. " 
echo "-hostfile : The user can specify the host names either through the -hosts option or by specifying the absolute path of a cluster configuration file. A sample host file contents are below: " 
echo
echo  "   stacg30 stacg30int 10.1.0.0 stacg30v  -"
echo  "   stacg34 stacg34int 10.1.0.1 stacg34v  -"
echo 
echo " The first column in each row of the host file will be used as the host name."
echo 
echo "-usePassphrase : The user wants to set up passphrase to encrypt the private key on the local host. " 
echo "-noPromptPassphrase : The user does not want to be prompted for passphrase related questions. This is for users who want the default behavior to be followed." 
echo "-shared : In case the user on the remote host has its home directory NFS mounted or shared across the remote hosts, this script should be used with -shared option. " 
echo "  It is possible for the user to determine whether a user's home directory is shared or non-shared. Let us say we want to determine that user user1's home directory is shared across hosts A, B and C."
echo " Follow the following steps:"
echo "    1. On host A, touch ~user1/checkSharedHome.tmp"
echo "    2. On hosts B and C, ls -al ~user1/checkSharedHome.tmp" 
echo "    3. If the file is present on hosts B and C in ~user1 directory and"
echo "       is identical on all hosts A, B, C, it means that the user's home "
echo "       directory is shared."
echo "    4. On host A, rm -f ~user1/checkSharedHome.tmp"
echo " In case the user accidentally passes -shared option for non-shared homes or viceversa,SSH connectivity would only be set up for a subset of the hosts. The user would have to re-run the setyp script with the correct option to rectify this problem."
echo "-advanced :  Specifying the -advanced option on the command line would result in SSH  connectivity being setup among the remote hosts which means that SSH can be used to run commands on one remote host from the other remote host or copy files between the remote hosts without being prompted for passwords or confirmations."
echo "-confirm: The script would remove write permissions on the remote hosts for the user home directory and ~/.ssh directory for "group" and "others". This is an SSH requirement. The user would be explicitly informed about this by the script and prompted to continue. In case the user presses no, the script would exit. In case the user does not want to be prompted, he can use -confirm option."
echo  "As a part of the setup, the script would use SSH to create files within ~/.ssh directory of the remote node and to setup the requisite permissions. The script also uses SCP to copy the local host public key to the remote hosts so that the remote hosts trust the local host for SSH. At the time, the script performs these steps, SSH connectivity has not been completely setup  hence the script would prompt the user for the remote host password.  "
echo "For each remote host, for remote users with non-shared homes this would be done once for SSH and  once for SCP. If the number of remote hosts are x, the user would be prompted  2x times for passwords. For remote users with shared homes, the user would be prompted only twice, once each for SCP and SSH.  For security reasons, the script does not save passwords and reuse it. Also, for security reasons, the script does not accept passwords redirected from a file. The user has to key in the confirmations and passwords at the prompts. "
echo "-verify : -verify option means that the user just wants to verify whether SSH has been set up. In this case, the script would not setup SSH but would only check whether SSH connectivity has been setup from the local host to the remote hosts. The script would run the date command on each remote host using SSH. In case the user is prompted for a password or sees a warning message for a particular host, it means SSH connectivity has not been setup correctly for that host.  In case the -verify option is not specified, the script would setup SSH and then do the verification as well. "
echo "-exverify : In case the user speciies the -exverify option, an exhaustive verification for all hosts would be done. In that case, the following would be checked: "
echo "   1. SSH connectivity from local host to all remote hosts. "
echo "   2. SSH connectivity from each remote host to itself and other remote hosts.  "
echo The -exverify option can be used in conjunction with the -verify option as well to do an exhaustive verification once the setup has been done.  
echo "Taking some examples: Let us say local host is Z, remote hosts are A,B and C. Local user is njerath. Remote users are racqa(non-shared), aime(shared)."
echo "$0 -user racqa -hosts "A B C" -advanced -exverify -confirm"
echo "Script would set up connectivity from Z -> A, Z -> B, Z -> C, A -> A, A -> B, A -> C, B -> A, B -> B, B -> C, C -> A, C -> B, C -> C."
echo "Since user has given -exverify option, all these scenario would be verified too."
echo
echo "Now the user runs : $0 -user racqa -hosts "A B C" -verify"
echo "Since -verify option is given, no SSH setup would be done, only verification of existing setup. Also, since -exverify or -advanced options are not given, script would only verify connectivity from Z -> A, Z -> B, Z -> C"

echo "Now the user runs : $0 -user racqa -hosts "A B C" -verify -advanced"
echo "Since -verify option is given, no SSH setup would be done, only verification of existing setup. Also, since  -advanced options is given, script would verify connectivity from Z -> A, Z -> B, Z -> C, A-> A, A->B, A->C, A->D"

echo "Now the user runs:"
echo "$0 -user aime -hosts "A B C" -confirm -shared"
echo "Script would set up connectivity between  Z->A, Z->B, Z->C only since advanced option is not given."
echo "All these scenarios would be verified too."

exit
fi

if test -z "$HOSTS"
then
   if test -n "$CLUSTER_CONFIGURATION_FILE" && test -f "$CLUSTER_CONFIGURATION_FILE"
   then
      HOSTS=`awk '$1 !~ /^#/ { str = str " " $1 } END { print str }' $CLUSTER_CONFIGURATION_FILE` 
   elif ! test -f "$CLUSTER_CONFIGURATION_FILE"
   then
     echo "Please specify a valid and existing cluster configuration file."
   fi
fi

if  test -z "$HOSTS" || test -z $USR
then
echo "Either user name or host information is missing"
echo "Usage $0 -user <user name> [ -hosts \"<space separated hostlist>\" | -hostfile <absolute path of cluster configuration file> ] [ -advanced ]  [ -verify] [ -exverify ] [ -logfile <desired absolute path of logfile> ] [-confirm] [-shared] [-help] [-usePassphrase] [-noPromptPassphrase]" 
exit 1
fi

if [ -d $LOGFILE ]; then
    echo $LOGFILE is a directory, setting logfile to $LOGFILE/ssh.log
    LOGFILE=$LOGFILE/ssh.log
fi

echo The output of this script is also logged into $LOGFILE | tee -a $LOGFILE

if [ `echo $?` != 0 ]; then
    echo Error writing to the logfile $LOGFILE, Exiting
    exit 1
fi

echo Hosts are $HOSTS | tee -a $LOGFILE
echo user is  $USR | tee -a $LOGFILE
SSH="/usr/bin/ssh"
SCP="/usr/bin/scp"
SSH_KEYGEN="/usr/bin/ssh-keygen"
calculateOS()
{
    platform=`uname -s`
    case "$platform"
    in
       "SunOS")  os=solaris;;
       "Linux")  os=linux;;
       "HP-UX")  os=hpunix;;
         "AIX")  os=aix;;
             *)  echo "Sorry, $platform is not currently supported." | tee -a $LOGFILE
                 exit 1;;
    esac

    echo "Platform:- $platform " | tee -a $LOGFILE
}
calculateOS
BITS=1024
ENCR="rsa"

deadhosts=""
alivehosts=""
if [ $platform = "Linux" ]
then
    PING="/bin/ping"
else
    PING="/usr/sbin/ping"
fi
#bug 9044791
if [ -n "$SSH_PATH" ]; then
    SSH=$SSH_PATH
fi
if [ -n "$SCP_PATH" ]; then
    SCP=$SCP_PATH
fi
if [ -n "$SSH_KEYGEN_PATH" ]; then
    SSH_KEYGEN=$SSH_KEYGEN_PATH
fi
if [ -n "$PING_PATH" ]; then
    PING=$PING_PATH
fi
PATH_ERROR=0
if test ! -x $SSH ; then
    echo "ssh not found at $SSH. Please set the variable SSH_PATH to the correct location of ssh and retry."
    PATH_ERROR=1
fi 
if test ! -x $SCP ; then
    echo "scp not found at $SCP. Please set the variable SCP_PATH to the correct location of scp and retry."
    PATH_ERROR=1
fi 
if test ! -x $SSH_KEYGEN ; then
    echo "ssh-keygen not found at $SSH_KEYGEN. Please set the variable SSH_KEYGEN_PATH to the correct location of ssh-keygen and retry."
    PATH_ERROR=1
fi 
if test ! -x $PING ; then
    echo "ping not found at $PING. Please set the variable PING_PATH to the correct location of ping and retry."
    PATH_ERROR=1
fi 
if [ $PATH_ERROR = 1 ]; then
    echo "ERROR: one or more of the required binaries not found, exiting"
    exit 1
fi
#9044791 end
echo Checking if the remote hosts are reachable | tee -a $LOGFILE
for host in $HOSTS
do
   if [ $platform = "SunOS" ]; then
       $PING -s $host 5 5
   elif [ $platform = "HP-UX" ]; then
       $PING $host -n 5 -m 5
   else
       $PING -c 5 -w 5 $host
   fi
  exitcode=`echo $?`
  if [ $exitcode = 0 ]
  then
     alivehosts="$alivehosts $host"
  else
     deadhosts="$deadhosts $host"
  fi
done

if test -z "$deadhosts"
then
   echo Remote host reachability check succeeded.  | tee -a $LOGFILE
   echo The following hosts are reachable: $alivehosts.  | tee -a $LOGFILE
   echo The following hosts are not reachable: $deadhosts.  | tee -a $LOGFILE
   echo All hosts are reachable. Proceeding further...  | tee -a $LOGFILE
else
   echo Remote host reachability check failed.  | tee -a $LOGFILE
   echo The following hosts are reachable: $alivehosts.  | tee -a $LOGFILE
   echo The following hosts are not reachable: $deadhosts.  | tee -a $LOGFILE
   echo Please ensure that all the hosts are up and re-run the script.  | tee -a $LOGFILE
   echo Exiting now...  | tee -a $LOGFILE
   exit 1
fi

firsthost=`echo $HOSTS | awk '{print $1}; END { }'`
echo firsthost $firsthost
numhosts=`echo $HOSTS | awk '{ }; END {print NF}'`
echo numhosts $numhosts

if [ $VERIFY = "true" ]
then
   echo Since user has specified -verify option, SSH setup would not be done. Only, existing SSH setup would be verified. | tee -a $LOGFILE
   continue
else
echo The script will setup SSH connectivity from the host ''`hostname`'' to all  | tee -a $LOGFILE 
echo the remote hosts. After the script is executed, the user can use SSH to run  | tee -a $LOGFILE 
echo commands on the remote hosts or copy files between this host ''`hostname`'' | tee -a $LOGFILE 
echo and the remote hosts without being prompted for passwords or confirmations. | tee -a $LOGFILE 
echo  | tee -a $LOGFILE 
echo NOTE 1: | tee -a $LOGFILE 
echo As part of the setup procedure, this script will use 'ssh' and 'scp' to copy | tee -a $LOGFILE 
echo files between the local host and the remote hosts. Since the script does not  | tee -a $LOGFILE 
echo store passwords, you may be prompted for the passwords during the execution of  | tee -a $LOGFILE 
echo the script whenever 'ssh' or 'scp' is invoked. | tee -a $LOGFILE 
echo  | tee -a $LOGFILE 
echo NOTE 2: | tee -a $LOGFILE 
echo "AS PER SSH REQUIREMENTS, THIS SCRIPT WILL SECURE THE USER HOME DIRECTORY" | tee -a $LOGFILE 
echo AND THE .ssh DIRECTORY BY REVOKING GROUP AND WORLD WRITE PRIVILEGES TO THESE  | tee -a $LOGFILE 
echo "directories." | tee -a $LOGFILE 
echo  | tee -a $LOGFILE 
echo "Do you want to continue and let the script make the above mentioned changes (yes/no)?" | tee -a $LOGFILE 

if [ "$CONFIRM" = "no" ] 
then 
  read CONFIRM 
else
  echo "Confirmation provided on the command line" | tee -a $LOGFILE
fi 
   
echo  | tee -a $LOGFILE 
echo The user chose ''$CONFIRM'' | tee -a $LOGFILE 

if [ -z "$CONFIRM" -o "$CONFIRM" != "yes" -a "$CONFIRM" != "no" ]
then
  echo "You haven't specified proper input. Please enter 'yes' or 'no'. Exiting...."
  exit 0
fi
if [ "$CONFIRM" = "no" ] 
then 
  echo "SSH setup is not done." | tee -a $LOGFILE 
  exit 1 
else 
  if [ $NO_PROMPT_PASSPHRASE = "yes" ]
  then
    echo "User chose to skip passphrase related questions."  | tee -a $LOGFILE
  else
    if [ $SHARED = "true" ]
    then
	  hostcount=`expr ${numhosts} + 1`
	  PASSPHRASE_PROMPT=`expr 2 \* $hostcount`
    else
	  PASSPHRASE_PROMPT=`expr 2 \* ${numhosts}`
    fi
    echo "Please specify if you want to specify a passphrase for the private key this script will create for the local host. Passphrase is used to encrypt the private key and makes SSH much more secure. Type 'yes' or 'no' and then press enter. In case you press 'yes', you would need to enter the passphrase whenever the script executes ssh or scp. $PASSPHRASE " | tee -a $LOGFILE
    echo "The estimated number of times the user would be prompted for a passphrase is $PASSPHRASE_PROMPT. In addition, if the private-public files are also newly created, the user would have to specify the passphrase on one additional occasion. " | tee -a $LOGFILE
    echo "Enter 'yes' or 'no'." | tee -a $LOGFILE
    if [ "$PASSPHRASE" = "no" ]
    then
      read PASSPHRASE
    else
      echo "Confirmation provided on the command line" | tee -a $LOGFILE
    fi 

    echo  | tee -a $LOGFILE 
    echo The user chose ''$PASSPHRASE'' | tee -a $LOGFILE 
    if [ -z "$PASSPHRASE"  -o "$PASSPHRASE" != "yes" -a "$PASSPHRASE" != "no" ]
    then
      echo "You haven't specified whether to use Passphrase or not. Please specify 'yes' or 'no'. Exiting..."
      exit 0
    fi

    if [ "$PASSPHRASE" = "yes" ] 
    then 
       RERUN_SSHKEYGEN="yes"
#Checking for existence of ${IDENTITY} file
       if test -f  $HOME/.ssh/${IDENTITY}.pub && test -f  $HOME/.ssh/${IDENTITY} 
       then
	     echo "The files containing the client public and private keys already exist on the local host. The current private key may or may not have a passphrase associated with it. In case you remember the passphrase and do not want to re-run ssh-keygen, press 'no' and enter. If you press 'no', the script will not attempt to create any new public/private key pairs. If you press 'yes', the script will remove the old private/public key files existing and create new ones prompting the user to enter the passphrase. If you enter 'yes', any previous SSH user setups would be reset. If you press 'change', the script will associate a new passphrase with the old keys." | tee -a $LOGFILE
	     echo "Press 'yes', 'no' or 'change'" | tee -a $LOGFILE
             read RERUN_SSHKEYGEN 
             echo The user chose ''$RERUN_SSHKEYGEN'' | tee -a $LOGFILE 
	     if [ -z "$RERUN_SSHKEYGEN" -o "$RERUN_SSHKEYGEN" != "yes" -a "$RERUN_SSHKEYGEN" != "no" -a "$RERUN_SSHKEYGEN" != "change" ]
	     then
	       echo "You haven't specified whether to re-run 'ssh-keygen' or not. Please enter 'yes' , 'no' or 'change'. Exiting..."
	       exit 0;
	     fi
       fi 
     else
       if test -f  $HOME/.ssh/${IDENTITY}.pub && test -f  $HOME/.ssh/${IDENTITY} 
       then
         echo "The files containing the client public and private keys already exist on the local host. The current private key may have a passphrase associated with it. In case you find using passphrase inconvenient(although it is more secure), you can change to it empty through this script. Press 'change' if you want the script to change the passphrase for you. Press 'no' if you want to use your old passphrase, if you had one."
         read RERUN_SSHKEYGEN 
         echo The user chose ''$RERUN_SSHKEYGEN'' | tee -a $LOGFILE 
	 if [ -z "$RERUN_SSHKEYGEN" -o "$RERUN_SSHKEYGEN" != "yes" -a "$RERUN_SSHKEYGEN" != "no" -a "$RERUN_SSHKEYGEN" != "change" ]
	 then
	   echo "You haven't specified whether to re-run 'ssh-keygen' or not. Please enter 'yes' , 'no' or 'change'. Exiting..."
	   exit 0
	 fi
       fi
     fi
  fi
  echo Creating .ssh directory on local host, if not present already | tee -a $LOGFILE
  mkdir -p $HOME/.ssh | tee -a $LOGFILE
echo Creating authorized_keys file on local host  | tee -a $LOGFILE
touch $HOME/.ssh/authorized_keys  | tee -a $LOGFILE
echo Changing permissions on authorized_keys to 644 on local host  | tee -a $LOGFILE
chmod 644 $HOME/.ssh/authorized_keys  | tee -a $LOGFILE
mv -f $HOME/.ssh/authorized_keys  $HOME/.ssh/authorized_keys.tmp | tee -a $LOGFILE
echo Creating known_hosts file on local host  | tee -a $LOGFILE
touch $HOME/.ssh/known_hosts  | tee -a $LOGFILE
echo Changing permissions on known_hosts to 644 on local host  | tee -a $LOGFILE
chmod 644 $HOME/.ssh/known_hosts  | tee -a $LOGFILE
mv -f $HOME/.ssh/known_hosts $HOME/.ssh/known_hosts.tmp | tee -a $LOGFILE


echo Creating config file on local host | tee -a $LOGFILE
echo If a config file exists already at $HOME/.ssh/config, it would be backed up to $HOME/.ssh/config.backup.
echo "Host *" > $HOME/.ssh/config.tmp | tee -a $LOGFILE
echo "ForwardX11 no" >> $HOME/.ssh/config.tmp | tee -a $LOGFILE

if test -f $HOME/.ssh/config 
then
  cp -f $HOME/.ssh/config $HOME/.ssh/config.backup
fi

mv -f $HOME/.ssh/config.tmp $HOME/.ssh/config  | tee -a $LOGFILE
chmod 644 $HOME/.ssh/config

if [ "$RERUN_SSHKEYGEN" = "yes" ]
then
  echo Removing old private/public keys on local host | tee -a $LOGFILE
  rm -f $HOME/.ssh/${IDENTITY} | tee -a $LOGFILE
  rm -f $HOME/.ssh/${IDENTITY}.pub | tee -a $LOGFILE
  echo Running SSH keygen on local host | tee -a $LOGFILE
  $SSH_KEYGEN -t $ENCR -b $BITS -f $HOME/.ssh/${IDENTITY}   | tee -a $LOGFILE

elif [ "$RERUN_SSHKEYGEN" = "change" ]
then
    echo Running SSH Keygen on local host to change the passphrase associated with the existing private key | tee -a $LOGFILE
    $SSH_KEYGEN -p -t $ENCR -b $BITS -f $HOME/.ssh/${IDENTITY} | tee -a $LOGFILE
elif test -f  $HOME/.ssh/${IDENTITY}.pub && test -f  $HOME/.ssh/${IDENTITY} 
then
    continue
else
    echo Removing old private/public keys on local host | tee -a $LOGFILE
    rm -f $HOME/.ssh/${IDENTITY} | tee -a $LOGFILE
    rm -f $HOME/.ssh/${IDENTITY}.pub | tee -a $LOGFILE
    echo Running SSH keygen on local host with empty passphrase | tee -a $LOGFILE
    $SSH_KEYGEN -t $ENCR -b $BITS -f $HOME/.ssh/${IDENTITY} -N ''  | tee -a $LOGFILE
fi

if [ $SHARED = "true" ]
then
  if [ $USER = $USR ]
  then
#No remote operations required
    echo Remote user is same as local user | tee -a $LOGFILE
    REMOTEHOSTS=""
    chmod og-w $HOME $HOME/.ssh | tee -a $LOGFILE
  else    
    REMOTEHOSTS="${firsthost}"
  fi
else
  REMOTEHOSTS="$HOSTS"
fi

for host in $REMOTEHOSTS
do
     echo Creating .ssh directory and setting permissions on remote host $host | tee -a $LOGFILE
     echo "THE SCRIPT WOULD ALSO BE REVOKING WRITE PERMISSIONS FOR "group" AND "others" ON THE HOME DIRECTORY FOR $USR. THIS IS AN SSH REQUIREMENT." | tee -a $LOGFILE
     echo The script would create ~$USR/.ssh/config file on remote host $host. If a config file exists already at ~$USR/.ssh/config, it would be backed up to ~$USR/.ssh/config.backup. | tee -a $LOGFILE
     echo The user may be prompted for a password here since the script would be running SSH on host $host. | tee -a $LOGFILE
     $SSH -o StrictHostKeyChecking=no -x -l $USR $host "/bin/sh -c \"  mkdir -p .ssh ; chmod og-w . .ssh;   touch .ssh/authorized_keys .ssh/known_hosts;  chmod 644 .ssh/authorized_keys  .ssh/known_hosts; cp  .ssh/authorized_keys .ssh/authorized_keys.tmp ;  cp .ssh/known_hosts .ssh/known_hosts.tmp; echo \\"Host *\\" > .ssh/config.tmp; echo \\"ForwardX11 no\\" >> .ssh/config.tmp; if test -f  .ssh/config ; then cp -f .ssh/config .ssh/config.backup; fi ; mv -f .ssh/config.tmp .ssh/config\""  | tee -a $LOGFILE
     echo Done with creating .ssh directory and setting permissions on remote host $host. | tee -a $LOGFILE
done

for host in $REMOTEHOSTS
do
  echo Copying local host public key to the remote host $host | tee -a $LOGFILE
  echo The user may be prompted for a password or passphrase here since the script would be using SCP for host $host. | tee -a $LOGFILE

  $SCP $HOME/.ssh/${IDENTITY}.pub  $USR@$host:.ssh/authorized_keys | tee -a $LOGFILE
  echo Done copying local host public key to the remote host $host | tee -a $LOGFILE
done

cat $HOME/.ssh/${IDENTITY}.pub >> $HOME/.ssh/authorized_keys | tee -a $LOGFILE

for host in $HOSTS
do
  if [ "$ADVANCED" = "true" ] 
  then
    echo Creating keys on remote host $host if they do not exist already. This is required to setup SSH on host $host. | tee -a $LOGFILE
    if [ "$SHARED" = "true" ]
    then
      IDENTITY_FILE_NAME=${IDENTITY}_$host
      COALESCE_IDENTITY_FILES_COMMAND="cat .ssh/${IDENTITY_FILE_NAME}.pub >> .ssh/authorized_keys"
    else
      IDENTITY_FILE_NAME=${IDENTITY}
    fi

   $SSH  -o StrictHostKeyChecking=no -x -l $USR $host " /bin/sh -c \"if test -f  .ssh/${IDENTITY_FILE_NAME}.pub && test -f  .ssh/${IDENTITY_FILE_NAME}; then echo; else rm -f .ssh/${IDENTITY_FILE_NAME} ;  rm -f .ssh/${IDENTITY_FILE_NAME}.pub ;  $SSH_KEYGEN -t $ENCR -b $BITS -f .ssh/${IDENTITY_FILE_NAME} -N '' ; fi; ${COALESCE_IDENTITY_FILES_COMMAND} \"" | tee -a $LOGFILE
  else 
#At least get the host keys from all hosts for shared case - advanced option not set
    if test  $SHARED = "true" && test $ADVANCED = "false"
    then
      if [ "$PASSPHRASE" = "yes" ]
      then
	 echo "The script will fetch the host keys from all hosts. The user may be prompted for a passphrase here in case the private key has been encrypted with a passphrase." | tee -a $LOGFILE
      fi
      $SSH  -o StrictHostKeyChecking=no -x -l $USR $host "/bin/sh -c true"
    fi
  fi
done

for host in $REMOTEHOSTS
do
  if test $ADVANCED = "true" && test $SHARED = "false"  
  then
      $SCP $USR@$host:.ssh/${IDENTITY}.pub $HOME/.ssh/${IDENTITY}.pub.$host | tee -a $LOGFILE
      cat $HOME/.ssh/${IDENTITY}.pub.$host >> $HOME/.ssh/authorized_keys | tee -a $LOGFILE
      rm -f $HOME/.ssh/${IDENTITY}.pub.$host | tee -a $LOGFILE
    fi
done

for host in $REMOTEHOSTS
do
   if [ "$ADVANCED" = "true" ]
   then
      if [ "$SHARED" != "true" ]
      then
         echo Updating authorized_keys file on remote host $host | tee -a $LOGFILE
         $SCP $HOME/.ssh/authorized_keys  $USR@$host:.ssh/authorized_keys | tee -a $LOGFILE
      fi 
     echo Updating known_hosts file on remote host $host | tee -a $LOGFILE
     $SCP $HOME/.ssh/known_hosts $USR@$host:.ssh/known_hosts | tee -a $LOGFILE
   fi
   if [ "$PASSPHRASE" = "yes" ]
   then
	 echo "The script will run SSH on the remote machine $host. The user may be prompted for a passphrase here in case the private key has been encrypted with a passphrase." | tee -a $LOGFILE
   fi
     $SSH -x -l $USR $host "/bin/sh -c \"cat .ssh/authorized_keys.tmp >> .ssh/authorized_keys; cat .ssh/known_hosts.tmp >> .ssh/known_hosts; rm -f  .ssh/known_hosts.tmp  .ssh/authorized_keys.tmp\"" | tee -a $LOGFILE
done

cat  $HOME/.ssh/known_hosts.tmp >> $HOME/.ssh/known_hosts | tee -a $LOGFILE
cat  $HOME/.ssh/authorized_keys.tmp >> $HOME/.ssh/authorized_keys | tee -a $LOGFILE
#Added chmod to fix BUG NO 5238814
chmod 644 $HOME/.ssh/authorized_keys
#Fix for BUG NO 5157782
chmod 644 $HOME/.ssh/config
rm -f  $HOME/.ssh/known_hosts.tmp $HOME/.ssh/authorized_keys.tmp | tee -a $LOGFILE
echo SSH setup is complete. | tee -a $LOGFILE
fi
fi

echo                                                                          | tee -a $LOGFILE
echo ------------------------------------------------------------------------ | tee -a $LOGFILE
echo Verifying SSH setup | tee -a $LOGFILE
echo =================== | tee -a $LOGFILE
echo The script will now run the 'date' command on the remote nodes using ssh | tee -a $LOGFILE
echo to verify if ssh is setup correctly. IF THE SETUP IS CORRECTLY SETUP,  | tee -a $LOGFILE
echo THERE SHOULD BE NO OUTPUT OTHER THAN THE DATE AND SSH SHOULD NOT ASK FOR | tee -a $LOGFILE
echo PASSWORDS. If you see any output other than date or are prompted for the | tee -a $LOGFILE
echo password, ssh is not setup correctly and you will need to resolve the  | tee -a $LOGFILE
echo issue and set up ssh again. | tee -a $LOGFILE
echo The possible causes for failure could be:  | tee -a $LOGFILE
echo   1. The server settings in /etc/ssh/sshd_config file do not allow ssh | tee -a $LOGFILE
echo      for user $USR. | tee -a $LOGFILE
echo   2. The server may have disabled public key based authentication.
echo   3. The client public key on the server may be outdated.
echo   4. ~$USR or  ~$USR/.ssh on the remote host may not be owned by $USR.  | tee -a $LOGFILE
echo   5. User may not have passed -shared option for shared remote users or | tee -a $LOGFILE
echo     may be passing the -shared option for non-shared remote users.  | tee -a $LOGFILE
echo   6. If there is output in addition to the date, but no password is asked, | tee -a $LOGFILE
echo   it may be a security alert shown as part of company policy. Append the | tee -a $LOGFILE
echo   "additional text to the <OMS HOME>/sysman/prov/resources/ignoreMessages.txt file." | tee -a $LOGFILE
echo ------------------------------------------------------------------------ | tee -a $LOGFILE
#read -t 30 dummy
  for host in $HOSTS
  do
    echo --$host:-- | tee -a $LOGFILE

     echo Running $SSH -x -l $USR $host date to verify SSH connectivity has been setup from local host to $host.  | tee -a $LOGFILE
     echo "IF YOU SEE ANY OTHER OUTPUT BESIDES THE OUTPUT OF THE DATE COMMAND OR IF YOU ARE PROMPTED FOR A PASSWORD HERE, IT MEANS SSH SETUP HAS NOT BEEN SUCCESSFUL. Please note that being prompted for a passphrase may be OK but being prompted for a password is ERROR." | tee -a $LOGFILE
     if [ "$PASSPHRASE" = "yes" ]
     then
       echo "The script will run SSH on the remote machine $host. The user may be prompted for a passphrase here in case the private key has been encrypted with a passphrase." | tee -a $LOGFILE
     fi
     $SSH -l $USR $host "/bin/sh -c date"  | tee -a $LOGFILE
echo ------------------------------------------------------------------------ | tee -a $LOGFILE
  done


if [ "$EXHAUSTIVE_VERIFY" = "true" ]
then
   for clienthost in $HOSTS
   do

      if [ "$SHARED" = "true" ]
      then
         REMOTESSH="$SSH -i .ssh/${IDENTITY}_${clienthost}"
      else
         REMOTESSH=$SSH
      fi

      for serverhost in  $HOSTS
      do
         echo ------------------------------------------------------------------------ | tee -a $LOGFILE
         echo Verifying SSH connectivity has been setup from $clienthost to $serverhost  | tee -a $LOGFILE
         echo ------------------------------------------------------------------------ | tee -a $LOGFILE
         echo "IF YOU SEE ANY OTHER OUTPUT BESIDES THE OUTPUT OF THE DATE COMMAND OR IF YOU ARE PROMPTED FOR A PASSWORD HERE, IT MEANS SSH SETUP HAS NOT BEEN SUCCESSFUL."  | tee -a $LOGFILE
         $SSH -l $USR $clienthost "$REMOTESSH $serverhost \"/bin/sh -c date\""  | tee -a $LOGFILE
         echo ------------------------------------------------------------------------ | tee -a $LOGFILE
      done  
       echo -Verification from $clienthost complete- | tee -a $LOGFILE
   done
else
   if [ "$ADVANCED" = "true" ]
   then
      if [ "$SHARED" = "true" ]
      then
         REMOTESSH="$SSH -i .ssh/${IDENTITY}_${firsthost}"
      else
         REMOTESSH=$SSH
      fi
     for host in $HOSTS
     do
         echo ------------------------------------------------------------------------ | tee -a $LOGFILE
        echo Verifying SSH connectivity has been setup from $firsthost to $host  | tee -a $LOGFILE
        echo "IF YOU SEE ANY OTHER OUTPUT BESIDES THE OUTPUT OF THE DATE COMMAND OR IF YOU ARE PROMPTED FOR A PASSWORD HERE, IT MEANS SSH SETUP HAS NOT BEEN SUCCESSFUL." | tee -a $LOGFILE
       $SSH -l $USR $firsthost "$REMOTESSH $host \"/bin/sh -c date\"" | tee -a $LOGFILE
         echo ------------------------------------------------------------------------ | tee -a $LOGFILE
    done
    echo -Verification from $clienthost complete- | tee -a $LOGFILE
  fi
fi
echo "SSH verification complete." | tee -a $LOGFILE
