aboutsummaryrefslogtreecommitdiff
path: root/lib/ed25519/src/ge.h
diff options
context:
space:
mode:
authorMark Haines <mark.haines@matrix.org>2015-03-03 11:14:50 +0000
committerMark Haines <mark.haines@matrix.org>2015-03-03 11:14:50 +0000
commit3ce450fc1984ac480ae158a40d60e9d42f77f74a (patch)
treeeb120d958eac8361d3760b9ad680fd8dc826d7a3 /lib/ed25519/src/ge.h
parent8bf99544160b1fd787e666b893c5117ab717bc99 (diff)
parent498dfabf9848286be003b42941c323a045d9fa46 (diff)
Merge commit '498dfabf9848286be003b42941c323a045d9fa46' as 'lib/ed25519'
Diffstat (limited to 'lib/ed25519/src/ge.h')
-rw-r--r--lib/ed25519/src/ge.h74
1 files changed, 74 insertions, 0 deletions
diff --git a/lib/ed25519/src/ge.h b/lib/ed25519/src/ge.h
new file mode 100644
index 0000000..17fde2d
--- /dev/null
+++ b/lib/ed25519/src/ge.h
@@ -0,0 +1,74 @@
+#ifndef GE_H
+#define GE_H
+
+#include "fe.h"
+
+
+/*
+ge means group element.
+
+Here the group is the set of pairs (x,y) of field elements (see fe.h)
+satisfying -x^2 + y^2 = 1 + d x^2y^2
+where d = -121665/121666.
+
+Representations:
+ ge_p2 (projective): (X:Y:Z) satisfying x=X/Z, y=Y/Z
+ ge_p3 (extended): (X:Y:Z:T) satisfying x=X/Z, y=Y/Z, XY=ZT
+ ge_p1p1 (completed): ((X:Z),(Y:T)) satisfying x=X/Z, y=Y/T
+ ge_precomp (Duif): (y+x,y-x,2dxy)
+*/
+
+typedef struct {
+ fe X;
+ fe Y;
+ fe Z;
+} ge_p2;
+
+typedef struct {
+ fe X;
+ fe Y;
+ fe Z;
+ fe T;
+} ge_p3;
+
+typedef struct {
+ fe X;
+ fe Y;
+ fe Z;
+ fe T;
+} ge_p1p1;
+
+typedef struct {
+ fe yplusx;
+ fe yminusx;
+ fe xy2d;
+} ge_precomp;
+
+typedef struct {
+ fe YplusX;
+ fe YminusX;
+ fe Z;
+ fe T2d;
+} ge_cached;
+
+void ge_p3_tobytes(unsigned char *s, const ge_p3 *h);
+void ge_tobytes(unsigned char *s, const ge_p2 *h);
+int ge_frombytes_negate_vartime(ge_p3 *h, const unsigned char *s);
+
+void ge_add(ge_p1p1 *r, const ge_p3 *p, const ge_cached *q);
+void ge_sub(ge_p1p1 *r, const ge_p3 *p, const ge_cached *q);
+void ge_double_scalarmult_vartime(ge_p2 *r, const unsigned char *a, const ge_p3 *A, const unsigned char *b);
+void ge_madd(ge_p1p1 *r, const ge_p3 *p, const ge_precomp *q);
+void ge_msub(ge_p1p1 *r, const ge_p3 *p, const ge_precomp *q);
+void ge_scalarmult_base(ge_p3 *h, const unsigned char *a);
+
+void ge_p1p1_to_p2(ge_p2 *r, const ge_p1p1 *p);
+void ge_p1p1_to_p3(ge_p3 *r, const ge_p1p1 *p);
+void ge_p2_0(ge_p2 *h);
+void ge_p2_dbl(ge_p1p1 *r, const ge_p2 *p);
+void ge_p3_0(ge_p3 *h);
+void ge_p3_dbl(ge_p1p1 *r, const ge_p3 *p);
+void ge_p3_to_cached(ge_cached *r, const ge_p3 *p);
+void ge_p3_to_p2(ge_p2 *r, const ge_p3 *p);
+
+#endif