makehosts

#!/bin/bash
# Read from a list of domain names, and use dig to create a hosts file that can be used 
# instead of DNS.
domains="${domains-domains}"
blacklist="${blacklist-blacklist}"
badlist="${badlist-badlist}"
if ! ls domains >/dev/null 2>/dev/null; then
  echo "You need to make a list of domain names (websites, like google.com), "
  echo "and put it in a file called \"domains\" (not domains.txt) in the "
  echo "working directory (currently $(pwd)/). "
  echo "You can also run the addomains script to add as many domains as you want,"
  echo "and then optimize it with the optdomains script."
  echo "When you have a domains file, run this script again."
  echo "If you absolutely need to run makehosts against a file other than 'domains',"
  echo "you can run: domains=/path/to/my/domainsfile $0"
  exit 1
fi
mkdir -p old
mv hosts old/hosts.backedup$(date +%y%m%d%s) 2>/dev/null
echo "# This hosts file generated by makehosts (by george) on $(date | sed 's/\ \ /\ 0/')." > hosts
echo -n Generating hosts file. . .\ 
dom=0
ips=0
dtim=0
stim=$(date +%s)
lnum=$(wc -l $domains | gawk '{print $1}')
wnum=$(wc -w $domains | gawk '{print $1}')
if [ "$lnum" != "$wnum" ]; then 
  echo "Please run the optdomains script, and make sure you have only"
  echo "one domain on each line of the 'domains' file."
  exit 1
fi
while read domain; do
  if [ -n "$1" -a "$1" == "-v" ]; then
    echo -n "$domain "
    verbose=yes
  fi
  grep -iq "^$domain$" "$blacklist" && continue # skip domains on the blacklist
  grep -iq "^$domain$" "$badlist" && (echo "127.0.0.1 $domain www.$domain" >> hosts) && continue # malware/bad domains
  list=$(dig +short $domain)
  for ipaddr in $list; do 
    if (echo $ipaddr | grep -e '^[0-9]\+\.[0-9]\+\.[0-9]\+\.[0-9]\+$' >/dev/null); then
      echo $ipaddr $domain www.$domain >> hosts
      let ips=$ips+1
    else 
      if [ -n "$verbose" ]; then 
        echo -n +\   #this is not an error, it just shows some extra info.
      fi
    fi
  done
  if [ $lnum -ge 250 -a $dtim -eq 0 ]; then 
    dtim=1
  elif [ $lnum -lt 250 ]; then 
    echo -n .\ 
  else 
    echo -n .\ 
    dtim=0
  fi
  let dom=$dom+1
done < $domains
etim=$(date +%s)
let tim=$etim-$stim
echo -n "# $dom domains resolved to $ips IPs in about $tim seconds. Finished $(date | sed 's/\ \ /\ 0/')." >> hosts
echo done.
echo "Tadah! All done. " >&2
echo "$dom domains resolved to $ips IPs in about $tim seconds." >&2
# To use this script, make a list of domain names in a file called 'domains'. Put 
# one domain name on each line of the file, and do not include www.blah domains, 
# as www.'s will be automatically added for each domain on the list.