# frozen_string_literal: true module ActiveRecord module Sanitization extend ActiveSupport::Concern module ClassMethods # Accepts an array or string of SQL conditions and sanitizes # them into a valid SQL fragment for a WHERE clause. # # sanitize_sql_for_conditions(["name=? and group_id=?", "foo'bar", 4]) # # => "name='foo''bar' and group_id=4" # # sanitize_sql_for_conditions(["name=:name and group_id=:group_id", name: "foo'bar", group_id: 4]) # # => "name='foo''bar' and group_id='4'" # # sanitize_sql_for_conditions(["name='%s' and group_id='%s'", "foo'bar", 4]) # # => "name='foo''bar' and group_id='4'" # # sanitize_sql_for_conditions("name='foo''bar' and group_id='4'") # # => "name='foo''bar' and group_id='4'" def sanitize_sql_for_conditions(condition) return nil if condition.blank? case condition when Array; sanitize_sql_array(condition) else condition end end alias :sanitize_sql :sanitize_sql_for_conditions # Accepts an array, hash, or string of SQL conditions and sanitizes # them into a valid SQL fragment for a SET clause. # # sanitize_sql_for_assignment(["name=? and group_id=?", nil, 4]) # # => "name=NULL and group_id=4" # # sanitize_sql_for_assignment(["name=:name and group_id=:group_id", name: nil, group_id: 4]) # # => "name=NULL and group_id=4" # # Post.sanitize_sql_for_assignment({ name: nil, group_id: 4 }) # # => "`posts`.`name` = NULL, `posts`.`group_id` = 4" # # sanitize_sql_for_assignment("name=NULL and group_id='4'") # # => "name=NULL and group_id='4'" def sanitize_sql_for_assignment(assignments, default_table_name = table_name) case assignments when Array; sanitize_sql_array(assignments) when Hash; sanitize_sql_hash_for_assignment(assignments, default_table_name) else assignments end end # Accepts an array, or string of SQL conditions and sanitizes # them into a valid SQL fragment for an ORDER clause. # # sanitize_sql_for_order(["field(id, ?)", [1,3,2]]) # # => "field(id, 1,3,2)" # # sanitize_sql_for_order("id ASC") # # => "id ASC" def sanitize_sql_for_order(condition) if condition.is_a?(Array) && condition.first.to_s.include?("?") disallow_raw_sql!( [condition.first], permit: connection.column_name_with_order_matcher ) # Ensure we aren't dealing with a subclass of String that might # override methods we use (e.g. Arel::Nodes::SqlLiteral). if condition.first.kind_of?(String) && !condition.first.instance_of?(String) condition = [String.new(condition.first), *condition[1..-1]] end Arel.sql(sanitize_sql_array(condition)) else condition end end # Sanitizes a hash of attribute/value pairs into SQL conditions for a SET clause. # # sanitize_sql_hash_for_assignment({ status: nil, group_id: 1 }, "posts") # # => "`posts`.`status` = NULL, `posts`.`group_id` = 1" def sanitize_sql_hash_for_assignment(attrs, table) c = connection attrs.map do |attr, value| type = type_for_attribute(attr) value = type.serialize(type.cast(value)) "#{c.quote_table_name_for_assignment(table, attr)} = #{c.quote(value)}" end.join(", ") end # Sanitizes a +string+ so that it is safe to use within an SQL # LIKE statement. This method uses +escape_character+ to escape all occurrences of "\", "_" and "%". # # sanitize_sql_like("100%") # # => "100\\%" # # sanitize_sql_like("snake_cased_string") # # => "snake\\_cased\\_string" # # sanitize_sql_like("100%", "!") # # => "100!%" # # sanitize_sql_like("snake_cased_string", "!") # # => "snake!_cased!_string" def sanitize_sql_like(string, escape_character = "\\") pattern = Regexp.union(escape_character, "%", "_") string.gsub(pattern) { |x| [escape_character, x].join } end # Accepts an array of conditions. The array has each value # sanitized and interpolated into the SQL statement. # # sanitize_sql_array(["name=? and group_id=?", "foo'bar", 4]) # # => "name='foo''bar' and group_id=4" # # sanitize_sql_array(["name=:name and group_id=:group_id", name: "foo'bar", group_id: 4]) # # => "name='foo''bar' and group_id=4" # # sanitize_sql_array(["name='%s' and group_id='%s'", "foo'bar", 4]) # # => "name='foo''bar' and group_id='4'" def sanitize_sql_array(ary) statement, *values = ary if values.first.is_a?(Hash) && /:\w+/.match?(statement) replace_named_bind_variables(statement, values.first) elsif statement.include?("?") replace_bind_variables(statement, values) elsif statement.blank? statement else statement % values.collect { |value| connection.quote_string(value.to_s) } end end def disallow_raw_sql!(args, permit: connection.column_name_matcher) # :nodoc: unexpected = nil args.each do |arg| next if arg.is_a?(Symbol) || Arel.arel_node?(arg) || permit.match?(arg.to_s) (unexpected ||= []) << arg end return unless unexpected if allow_unsafe_raw_sql == :deprecated ActiveSupport::Deprecation.warn( "Dangerous query method (method whose arguments are used as raw " \ "SQL) called with non-attribute argument(s): " \ "#{unexpected.map(&:inspect).join(", ")}. Non-attribute " \ "arguments will be disallowed in Rails 6.1. This method should " \ "not be called with user-provided values, such as request " \ "parameters or model attributes. Known-safe values can be passed " \ "by wrapping them in Arel.sql()." ) else raise(ActiveRecord::UnknownAttributeReference, "Query method called with non-attribute argument(s): " + unexpected.map(&:inspect).join(", ") ) end end private def replace_bind_variables(statement, values) raise_if_bind_arity_mismatch(statement, statement.count("?"), values.size) bound = values.dup c = connection statement.gsub(/\?/) do replace_bind_variable(bound.shift, c) end end def replace_bind_variable(value, c = connection) if ActiveRecord::Relation === value value.to_sql else quote_bound_value(value, c) end end def replace_named_bind_variables(statement, bind_vars) statement.gsub(/(:?):([a-zA-Z]\w*)/) do |match| if $1 == ":" # skip postgresql casts match # return the whole match elsif bind_vars.include?(match = $2.to_sym) replace_bind_variable(bind_vars[match]) else raise PreparedStatementInvalid, "missing value for :#{match} in #{statement}" end end end def quote_bound_value(value, c = connection) if value.respond_to?(:map) && !value.acts_like?(:string) quoted = value.map { |v| c.quote(v) } if quoted.empty? c.quote(nil) else quoted.join(",") end else c.quote(value) end end def raise_if_bind_arity_mismatch(statement, expected, provided) unless expected == provided raise PreparedStatementInvalid, "wrong number of bind variables (#{provided} for #{expected}) in: #{statement}" end end end end end