diff --git a/collab.rb b/collab.rb
index fe151e2..691436a 100644
--- a/collab.rb
+++ b/collab.rb
@@ -2,13 +2,13 @@ require 'fileutils'
 
 POSIX_NAME_PREFIX = "emacs"
 
-
 $user_count = 0
 $users = []
 $id_map = {}
 
-
-## User manipulation
+#####################
+# User manipulation #
+#####################
 
 class User
   attr_accessor :id, :path, :posixname
@@ -47,7 +47,9 @@ def remove_user(id)
   $user_count -= 1
 end
 
-## Key manipulation
+####################
+# Key manipulation #
+####################
 
 class SSHKey
   attr_accessor :cipher, :pubkey, :comment
@@ -57,17 +59,83 @@ class SSHKey
     @pubkey  = pubkey
     @comment = comment
   end
-end
 
-def get_ssh_keys(id)
-  user = get_user(id)
-  extract_ssh_keys("#{user.path}/.ssh/authorized_keys").each do |k|
-    puts k.comment
+  def ==(o)
+    o.class == self.class && o.attrs == attrs
+  end
+  
+  def pretty
+    "#{@cipher} #{@comment}"
+  end
+  
+  def to_s
+    "ssh-#{@cipher} #{@pubkey} #{@comment}"
+  end
+
+  def attrs
+    [@cipher, @pubkey, @comment]
   end
 end
 
-def extract_ssh_keys(file)
+def get_ssh_keyfile(user,mode,&block)
+  file = File.open("#{user.path}/.ssh/authorized_keys",mode)
+  return file unless block_given?
+  yield(file)
+ensure
+  file.close
+end
+
+def get_ssh_pubkeys(user)
+  extract_ssh_pubkeys("#{user.path}/.ssh/authorized_keys")
+end
+
+def add_ssh_pubkey(user,key)
+  if not valid_pubkey? key then raise "Public key not valid" end
+  get_ssh_keyfile(user,"a") do |key_file|
+    key_file << "#{key.to_s}\n"
+  end
+end
+
+def reset_pubkeys(user)
+  FileUtils.rm "#{user.path}/.ssh/authorized_keys"
+  FileUtils.touch "#{user.path}/.ssh/authorized_keys"
+  FileUtils.chown_R user.id, user.id, "#{user.path}/.ssh"
+end
+
+def remove_ssh_pubkey(user,key)
+  keys = get_ssh_pubkeys(user)
+  reset_pubkeys(user)
+  keys.each{ |k| unless k == key then add_ssh_pubkey(user,k) end}
+end
+
+def remove_ssh_pubkey_by_key
+end
+
+def remove_ssh_pubkey_by_comment
+end
+
+def valid_pubkey?(key)
+  IO.popen("ssh-keygen -qlf -","r+") do |io|
+    io.write key.to_s
+    io.close_write
+    io.read
+  end
+  if $?.to_i == 0
+    true
+  else
+    false
+  end
+end
+
+def extract_ssh_pubkeys(file)
   File.open(file,"r") do |f|
     f.read.split("\n").select{ |line| line[0..2] == "ssh" }.map{ |ks| k = ks.split(" "); SSHKey.new(k[0][4..6], k[1], k[2]) }
   end
 end
+
+##################
+
+
+remove_user 5
+add_user 5
+add_ssh_pubkey(get_user(5), "ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQC7ZKN2fKcUQUaQqDjNCQQBSdqBVGX7lprNCJmceDBfybhbnuZJ8KvzJJIJIIbzqheW5BVCfkWJY6OgkpAumLWSRCS5n2+AnDHwQgpKDS93OeV+9/kattVtsVUBZaghymyJ2UfA0r918dkxcT9SZbNSl9raiDUUmj3JY8UM219BQP7BRqoZ6e/YZz9lO7ORy6yQT6fIMaVOaZcoDPr6oyNJfadm9POvS/Wl63onoRI9dzpHQG9RuHCcUhHJhkGtzY7GeRWc85WqA9Q4vYo0SK5Je9BG1cvAAVTfV+eYEJEiSDMwWj60roH0C3/ipmzxD/kWqg6YBJWL+XAyQkDnmbuD christoffermadsen@strawberry.thedevcave.net")