Generating additional constraints in algebraic cryptanalysis using SAT oracles

We describe a new technique aimed to generate new constraints which augment with the original set of constraints for a problem of algebraic cryptanalysis. In case the original problem is reduced to a system of Multivariate Quadratic equations over GF(2), the generated constraints can be in the form of linear equations over two-element field. If the considered problem is reduced to SAT, then new constraints are in the form of logic equivalences, anti-equivalences or unit resolvents. In both cases we demonstrate that new constraints generated by the proposed technique can decrease the complexity estimation of attacks on considered functions.