include/pbc_mnt.h

   1 //requires
   2 // * gmp.h
   3 #ifndef __PBC_MNT_H__
   4 #define __PBC_MNT_H__
   5
   6 struct pbc_cm_s {
   7   mpz_t q; //curve defined over F_q
   8   mpz_t n; //has order n (= q - t + 1) in F_q (and r^2 in F_q^k)
   9   mpz_t h; //h * r = n, r is prime
  10   mpz_t r;
  11   int D; //discrminant needed to find j-invariant
  12   int k; //embedding degree
  13 };
  14
  15 typedef struct pbc_cm_s *pbc_cm_ptr;
  16 typedef struct pbc_cm_s pbc_cm_t[1];
  17
  18 /*@manual cminfo
  19 Initializes 'cm'.
  20 */
  21 void pbc_cm_init(pbc_cm_t cm);
  22 /*@manual cminfo
  23 Clears 'cm'.
  24 */
  25 void pbc_cm_clear(pbc_cm_t cm);
  26
  27 /*@manual cminfo
  28 For a given discriminant D, searches for type D pairings suitable for
  29 cryptography (MNT curves of embedding degree 6).
  30 The group order is at most 'bitlimit' bits. For each set of CM parameters
  31 found, call 'callback' with +pbc_cm_t+ and given +void *+. If the callback
  32 returns nonzero, stops search and returns that value.
  33 Otherwise returns 0.
  34 */
  35 int pbc_cm_search_d(int (*callback)(pbc_cm_ptr, void *), void *data,
  36   unsigned int D, unsigned int bitlimit);
  37
  38 /*@manual cminfo
  39 For a given discriminant D, searches for type G pairings suitable for
  40 cryptography (Freeman curve).
  41 The group order is at most 'bitlimit' bits. For each set of CM parameters
  42 found, call 'callback' with +pbc_cm_t+ and given +void *+. If the callback
  43 returns nonzero, stops search and returns that value.
  44 Otherwise returns 0.
  45 */
  46 int pbc_cm_search_g(int (*callback)(pbc_cm_ptr, void *), void *data,
  47   unsigned int D, unsigned int bitlimit);
  48
  49 #endif //__PBC_MNT_H__