1 files changed, 110 insertions, 0 deletions
diff --git a/lib/gitlab/auth/ldap/adapter.rb b/lib/gitlab/auth/ldap/adapter.rb
new file mode 100644
index 00000000000..caf2d18c668
--- /dev/null
+++ b/lib/gitlab/auth/ldap/adapter.rb
@@ -0,0 +1,110 @@
+module Gitlab
+  module Auth
+    module LDAP
+      class Adapter
+        attr_reader :provider, :ldap
+
+        def self.open(provider, &block)
+          Net::LDAP.open(config(provider).adapter_options) do |ldap|
+            block.call(self.new(provider, ldap))
+          end
+        end
+
+        def self.config(provider)
+          Gitlab::Auth::LDAP::Config.new(provider)
+        end
+
+        def initialize(provider, ldap = nil)
+          @provider = provider
+          @ldap = ldap || Net::LDAP.new(config.adapter_options)
+        end
+
+        def config
+          Gitlab::Auth::LDAP::Config.new(provider)
+        end
+
+        def users(fields, value, limit = nil)
+          options = user_options(Array(fields), value, limit)
+
+          entries = ldap_search(options).select do |entry|
+            entry.respond_to? config.uid
+          end
+
+          entries.map do |entry|
+            Gitlab::Auth::LDAP::Person.new(entry, provider)
+          end
+        end
+
+        def user(*args)
+          users(*args).first
+        end
+
+        def dn_matches_filter?(dn, filter)
+          ldap_search(base: dn,
+                      filter: filter,
+                      scope: Net::LDAP::SearchScope_BaseObject,
+                      attributes: %w{dn}).any?
+        end
+
+        def ldap_search(*args)
+          # Net::LDAP's `time` argument doesn't work. Use Ruby `Timeout` instead.
+          Timeout.timeout(config.timeout) do
+            results = ldap.search(*args)
+
+            if results.nil?
+              response = ldap.get_operation_result
+
+              unless response.code.zero?
+                Rails.logger.warn("LDAP search error: #{response.message}")
+              end
+
+              []
+            else
+              results
+            end
+          end
+        rescue Net::LDAP::Error => error
+          Rails.logger.warn("LDAP search raised exception #{error.class}: #{error.message}")
+          []
+        rescue Timeout::Error
+          Rails.logger.warn("LDAP search timed out after #{config.timeout} seconds")
+          []
+        end
+
+        private
+
+        def user_options(fields, value, limit)
+          options = {
+            attributes: Gitlab::Auth::LDAP::Person.ldap_attributes(config),
+            base: config.base
+          }
+
+          options[:size] = limit if limit
+
+          if fields.include?('dn')
+            raise ArgumentError, 'It is not currently possible to search the DN and other fields at the same time.' if fields.size > 1
+
+            options[:base] = value
+            options[:scope] = Net::LDAP::SearchScope_BaseObject
+          else
+            filter = fields.map { |field| Net::LDAP::Filter.eq(field, value) }.inject(:|)
+          end
+
+          options.merge(filter: user_filter(filter))
+        end
+
+        def user_filter(filter = nil)
+          user_filter = config.constructed_user_filter if config.user_filter.present?
+
+          if user_filter && filter
+            Net::LDAP::Filter.join(filter, user_filter)
+          elsif user_filter
+            user_filter
+          else
+            filter
+          end
+        end
+      end
+    end
+  end
+end