Merge pull request #408 from elyscape/feature/pw_hash

(MODULES-1737) Add pw_hash() function

1 files changed, 56 insertions, 0 deletions

diff --git a/lib/puppet/parser/functions/pw_hash.rb b/lib/puppet/parser/functions/pw_hash.rb
new file mode 100644
index 0000000..ad3e393
--- /dev/null
+++ b/lib/puppet/parser/functions/pw_hash.rb
@@ -0,0 +1,56 @@
+Puppet::Parser::Functions::newfunction(
+  :pw_hash,
+  :type => :rvalue,
+  :arity => 3,
+  :doc => "Hashes a password using the crypt function. Provides a hash
+  usable on most POSIX systems.
+
+  The first argument to this function is the password to hash. If it is
+  undef or an empty string, this function returns undef.
+
+  The second argument to this function is which type of hash to use. It
+  will be converted into the appropriate crypt(3) hash specifier. Valid
+  hash types are:
+
+  |Hash type            |Specifier|
+  |---------------------|---------|
+  |MD5                  |1        |
+  |SHA-256              |5        |
+  |SHA-512 (recommended)|6        |
+
+  The third argument to this function is the salt to use.
+
+  Note: this uses the Puppet Master's implementation of crypt(3). If your
+  environment contains several different operating systems, ensure that they
+  are compatible before using this function.") do |args|
+    raise ArgumentError, "pw_hash(): wrong number of arguments (#{args.size} for 3)" if args.size != 3
+    raise ArgumentError, "pw_hash(): first argument must be a string" unless args[0].is_a? String or args[0].nil?
+    raise ArgumentError, "pw_hash(): second argument must be a string" unless args[1].is_a? String
+    hashes = { 'md5'     => '1',
+               'sha-256' => '5',
+               'sha-512' => '6' }
+    hash_type = hashes[args[1].downcase]
+    raise ArgumentError, "pw_hash(): #{args[1]} is not a valid hash type" if hash_type.nil?
+    raise ArgumentError, "pw_hash(): third argument must be a string" unless args[2].is_a? String
+    raise ArgumentError, "pw_hash(): third argument must not be empty" if args[2].empty?
+    raise ArgumentError, "pw_hash(): characters in salt must be in the set [a-zA-Z0-9./]" unless args[2].match(/\A[a-zA-Z0-9.\/]+\z/)
+
+    password = args[0]
+    return nil if password.nil? or password.empty?
+
+    # handle weak implementations of String#crypt
+    if 'test'.crypt('$1$1') != '$1$1$Bp8CU9Oujr9SSEw53WV6G.'
+      # JRuby < 1.7.17
+      if RUBY_PLATFORM == 'java'
+        # override String#crypt for password variable
+        def password.crypt(salt)
+          # puppetserver bundles Apache Commons Codec
+          org.apache.commons.codec.digest.Crypt.crypt(self.to_java_bytes, salt)
+        end
+      else
+        # MS Windows and other systems that don't support enhanced salts
+        raise Puppet::ParseError, 'system does not support enhanced salts'
+      end
+    end
+    password.crypt("$#{hash_type}$#{args[2]}")
+end