text: #ifndef ed25519_ref10_H
  #define ed25519_ref10_H
  
  #include <stddef.h>
  #include <stdint.h>
  
  /*
   fe means field element.
   Here the field is \Z/(2^255-19).
   */
  
  #ifdef HAVE_TI_MODE
  typedef uint64_t fe25519[5];
  #else
  typedef int32_t fe25519[10];
  #endif
  
  void fe25519_invert(fe25519 out, const fe25519 z);
  void fe25519_frombytes(fe25519 h, const unsigned char *s);
  void fe25519_tobytes(unsigned char *s, const fe25519 h);
  
  # include "ed25519_ref10_fe_25_5.h"
  
  /*
   ge means group element.
  
   Here the group is the set of pairs (x,y) of field elements
   satisfying -x^2 + y^2 = 1 + d x^2y^2
   where d = -121665/121666.
  
   Representations:
   ge25519_p2 (projective): (X:Y:Z) satisfying x=X/Z, y=Y/Z
   ge25519_p3 (extended): (X:Y:Z:T) satisfying x=X/Z, y=Y/Z, XY=ZT
   ge25519_p1p1 (completed): ((X:Z),(Y:T)) satisfying x=X/Z, y=Y/T
   ge25519_precomp (Duif): (y+x,y-x,2dxy)
   */
  
  typedef struct {
      fe25519 X;
      fe25519 Y;
      fe25519 Z;
  } ge25519_p2;
  
  typedef struct {
      fe25519 X;
      fe25519 Y;
      fe25519 Z;
      fe25519 T;
  } ge25519_p3;
  
  typedef struct {
      fe25519 X;
      fe25519 Y;
      fe25519 Z;
      fe25519 T;
  } ge25519_p1p1;
  
  typedef struct {
      fe25519 yplusx;
      fe25519 yminusx;
      fe25519 xy2d;
  } ge25519_precomp;
  
  typedef struct {
      fe25519 YplusX;
      fe25519 YminusX;
      fe25519 Z;
      fe25519 T2d;
  } ge25519_cached;
  
  void ge25519_tobytes(unsigned char *s, const ge25519_p2 *h);
  
  void ge25519_p3_tobytes(unsigned char *s, const ge25519_p3 *h);
  
  int ge25519_frombytes(ge25519_p3 *h, const unsigned char *s);
  
  int ge25519_frombytes_negate_vartime(ge25519_p3 *h, const unsigned char *s);
  
  void ge25519_p3_to_cached(ge25519_cached *r, const ge25519_p3 *p);
  
  void ge25519_p1p1_to_p2(ge25519_p2 *r, const ge25519_p1p1 *p);
  
  void ge25519_p1p1_to_p3(ge25519_p3 *r, const ge25519_p1p1 *p);
  
  void ge25519_add(ge25519_p1p1 *r, const ge25519_p3 *p, const ge25519_cached *q);
  
  void ge25519_sub(ge25519_p1p1 *r, const ge25519_p3 *p, const ge25519_cached *q);
  
  void ge25519_scalarmult_base(ge25519_p3 *h, const unsigned char *a);
  
  void ge25519_double_scalarmult_vartime(ge25519_p2 *r, const unsigned char *a,
                                         const ge25519_p3 *A,
                                         const unsigned char *b);
  
  void ge25519_scalarmult(ge25519_p3 *h, const unsigned char *a,
                          const ge25519_p3 *p);
  
  int ge25519_is_canonical(const unsigned char *s);
  
  int ge25519_is_on_curve(const ge25519_p3 *p);
  
  int ge25519_is_on_main_subgroup(const ge25519_p3 *p);
  
  int ge25519_has_small_order(const unsigned char s[32]);
  
  void ge25519_from_uniform(unsigned char s[32], const unsigned char r[32]);
  
  /*
   The set of scalars is \Z/l
   where l = 2^252 + 27742317777372353535851937790883648493.
   */
  
  void sc25519_reduce(unsigned char *s);
  
  void sc25519_muladd(unsigned char *s, const unsigned char *a,
                      const unsigned char *b, const unsigned char *c);
  
  int sc25519_is_canonical(const unsigned char *s);
  
  #endif
  