#!/bin/bash

if [ "`id -u`" != "0" ]; then
  echo "Must be run as root"
  exit 1
fi

user="$1"
if [ "$user" == "" ]; then
    user=`cat /root/submissions/user 2>/dev/null`
    if [ "$user" == "" ]; then
	echo "parameter user missing. Usage: $0 <user> [<optional-server-address>] [<force-redo>]"
	exit 1
    fi
fi
if [ "$2" != "" ]; then
    BOCASERVER=$2
else
  if [[ ! -e /etc/bocaip ]] ; then
      echo "O IP do servidor boca nao configurado. Usando bombonera.org"
      BOCASERVER=50.116.19.221
  else
      source /etc/bocaip
      BOCASERVER=$BOCAIP
  fi
fi
if [ "$BOCASERVER" == "" ]; then
    echo "BOCA server not defined. Aborting"
    exit 1
fi

echo "Server at $BOCASERVER"
for i in wget sha256sum cut; do
    p=`which $i`
    if [ -x "$p" ]; then
	echo -n ""
    else
	echo "$i" not found
	exit 1
    fi
done
temp=/root/.temp.`date +%s%N`.txt

mkdir -p /root/.ssh
if [ ! -f /root/.ssh/$BOCASERVER -o ! -f /root/.ssh/$BOCASERVER.pub -o ! -f /root/.ssh/authorized_keys -o "$3" != "" ]; then
    ssh-keygen -q -f /root/.ssh/$BOCASERVER -t rsa -b 4096 -C "${user}@bombonera.org" -N ''
    echo -e "Host $BOCASERVER\n  HostName $BOCASERVER\n  User bocassh\n  IdentityFile /root/.ssh/$BOCASERVER\n" > /root/.ssh/config
    chmod 600 /root/.ssh/config

    if [ -f /root/submissions/code ]; then
	ress=`cat /root/submissions/code`
    else
	read -s -p "Password: " pass
	echo ""
	ress=`echo -n $pass | sha256sum - | cut -f1 -d' '`
    fi
    
    md=`wget -4 --no-check-certificate -t 2 -T 5 -S https://$BOCASERVER/boca/updatessh.php -O /dev/null --save-cookies ${temp}.cookie.txt --keep-session-cookies 2>&1 | grep PHPSESS | tail -n1`
    echo "$md" | grep -q PHPSESS
    if [ "$?" == "0" ]; then
	md=`echo $md | cut -f2 -d'=' | cut -f1 -d';'`
	res=`echo -n "${ress}${md}" | sha256sum - | cut -f1 -d' '`

	echo -n "name=${user}" > $temp
	[ -f /root/submissions/comp ] && echo -n "&comp=`cat /root/submissions/comp`" >> $temp
	echo -n "&password=$res" >> $temp
	echo -n "&data=" >> $temp
	cat /root/.ssh/$BOCASERVER.pub | uuencode -m zzzzzzzzzz | grep -v "begin-base64.*zzzzzzzzzz" | perl -MURI::Escape -lne 'print uri_escape($_)' >> $temp

	wget -4 --no-check-certificate -t 2 -T 5 "https://$BOCASERVER/boca/updatessh.php" --load-cookies ${temp}.cookie.txt --keep-session-cookies --save-cookies ${temp}.cookie.txt -O ${temp}.out --post-file=$temp >/dev/null 2>/dev/null
	rm -f $temp
	rm -f ${temp}.cookie.txt
	grep -qi incorrect ${temp}.out
	res=$?
	if [ "$res" == "0" ]; then
	    rm ${temp}.out
	    echo "$BOCASERVER: User or password incorrect"
	    exit 3
	fi
	grep -qi ssh-rsa ${temp}.out
	if [ "$?" == "0" ]; then
	    grep -i ssh-rsa ${temp}.out >> /root/.ssh/authorized_keys
	    chmod 700 /root/.ssh
	    chmod 600 /root/.ssh/authorized_keys
	fi
	rm ${temp}.out
    else
	echo "$BOCASERVER: connection failed"
	exit 2
    fi
    echo "authentication successful"
fi

if [ -f /etc/ssh/sshd_config ]; then
    grep -iq "^[[:space:]]*AllowUsers" /etc/ssh/sshd_config
    if [ "$?" != "0" ]; then
	grep -v -i "^[[:space:]]*AllowUsers" /etc/ssh/sshd_config | grep -v -i "^[[:space:]]*PermitRootLogin" | grep -v -i "^[[:space:]]*PasswordAuthentication" > /etc/ssh/sshd_config.tmp
	echo "AllowUsers root" >> /etc/ssh/sshd_config.tmp
	echo "PasswordAuthentication no" >> /etc/ssh/sshd_config.tmp
	echo "PermitRootLogin yes" >> /etc/ssh/sshd_config.tmp
	mv /etc/ssh/sshd_config.tmp /etc/ssh/sshd_config
	service ssh restart
    fi
fi

porta=5000
while [ $porta -lt 6000 ]; do
    pids=`ps auxw | grep "ssh -v -f -N" | grep ${BOCASERVER} | awk '{print $2;}'`
    if [ "$pids" != "" ]; then
	kill -9 $pids
    fi
    echo "Trying $porta"
    ssh -v -f -N -o UserKnownHostsFile=/dev/null -o PasswordAuthentication=no -o StrictHostKeyChecking=no -R ${porta}:localhost:22 bocassh@${BOCASERVER} >$temp 2>&1
    for k in 1 2 3 4 5 6 7 8; do
	sleep 1
	grep -q "remote forward.*for:" $temp
	if [ $? == 0 ]; then
	    break
	fi
    done
    grep -q "remote forward success for:" $temp
    if [ $? == 0 ]; then
	echo "Forward successful at $porta"
	break
    fi
    let "porta = $porta + 1"
done
exit 0