I'm doing summer cryptography research and I am have been looking for a security analysis of the Guillou-Quisquater (GQ) digital signature scheme, but I have been unable to find one.


Since this is not a very common digital signature scheme I will mention the protocol.



> 
> GQ: Public: $n,e,I$ has function $H$, where $I \equiv S^{e} \mod n$
> 
> 
> Private: $s$
> 
> 
> Signature: $(x,y)$ where $x \equiv r^{e} \mod n, c=h(m,x)$, and $y \equiv rS^{c} \mod n$
> 
> 
> To verify: Check that $y^{e} \equiv x I^{h(m,x)} \mod n$ (this works because $y^{e} \equiv (rS^{c})^{e} \equiv r^{e}S^{ce} \equiv xI^{c}$)
> 
> 
> 


Any references to papers in which this could be found would be very helpful.
Thank you!



Is there a security analysis of the GQ digital signature scheme?
[M. Bellare, A. Palacio - GQ and Schnorr Identification Schemes: Proofs of Security against Impersonation under Active and Concurrent Attacks](http://cseweb.ucsd.edu/~mihir/papers/gq.pdf)


