From c000e6bb85d10161f2816cc44b966adac7628791 Mon Sep 17 00:00:00 2001
From: Orson Peters <orsonpeters@gmail.com>
Date: Fri, 11 Jan 2013 22:32:39 +0100
Subject: [PATCH] work on seed generation

---
 fe_isnonzero.c |   4 +-
 keypair.c      |   2 +
 open.c         |  33 -----
 sc_muladd.c    | 366 -------------------------------------------------
 sc_reduce.c    | 273 ------------------------------------
 test.c         |   9 +-
 verify.c       |  69 +++++-----
 verify.h       |   7 +-
 8 files changed, 50 insertions(+), 713 deletions(-)
 delete mode 100644 open.c
 delete mode 100644 sc_muladd.c
 delete mode 100644 sc_reduce.c

diff --git a/fe_isnonzero.c b/fe_isnonzero.c
index 074fee8..e8a4ce1 100644
--- a/fe_isnonzero.c
+++ b/fe_isnonzero.c
@@ -1,5 +1,5 @@
 #include "fe.h"
-#include "verify.h"
+#include "consttime_cmp.h"
 
 
 /*
@@ -16,5 +16,5 @@ int fe_isnonzero(const fe f)
 {
   unsigned char s[32];
   fe_tobytes(s,f);
-  return crypto_verify_32(s,zero);
+  return consttime_cmp_32(s, zero);
 }
diff --git a/keypair.c b/keypair.c
index cf5ceae..77e19d1 100644
--- a/keypair.c
+++ b/keypair.c
@@ -2,6 +2,8 @@
 #include "sha512.h"
 #include "ge.h"
 
+
+
 int ed25519_create_keypair(unsigned char *verify_key, unsigned char *sign_key, unsigned char *seed)
 {
   unsigned char h[64];
diff --git a/open.c b/open.c
deleted file mode 100644
index 456be43..0000000
--- a/open.c
+++ /dev/null
@@ -1,33 +0,0 @@
-#include "ed25519.h"
-#include "sha512.h"
-#include "ge.h"
-#include "sc.h"
-#include "verify.h"
-
-int ed25519_verify(const unsigned char *signature, const unsigned char *message, unsigned int message_len, const unsigned char *verify_key)
-{
-  unsigned char h[64];
-  unsigned char checker[32];
-  sha512_ctx hash;
-  ge_p3 A;
-  ge_p2 R;
-
-  if (signature[63] & 224) return -1;
-  if (ge_frombytes_negate_vartime(&A,verify_key) != 0) return -1;
-
-  sha512_init(&hash);
-  sha512_update(&hash, signature, 32);
-  sha512_update(&hash, verify_key, 32);
-  sha512_update(&hash, message, message_len);
-  sha512_final(&hash, h);
-
-  sc_reduce(h);
-
-  ge_double_scalarmult_vartime(&R,h,&A,signature + 32);
-  ge_tobytes(checker, &R);
-  if (crypto_verify_32(checker, signature) != 0) {
-    return -1;
-  }
-
-  return 0;
-}
diff --git a/sc_muladd.c b/sc_muladd.c
deleted file mode 100644
index 67dc4d4..0000000
--- a/sc_muladd.c
+++ /dev/null
@@ -1,366 +0,0 @@
-#include "sc.h"
-#include "pstdint.h"
-
-static uint64_t load_3(const unsigned char *in)
-{
-  uint64_t result;
-  result = (uint64_t) in[0];
-  result |= ((uint64_t) in[1]) << 8;
-  result |= ((uint64_t) in[2]) << 16;
-  return result;
-}
-
-static uint64_t load_4(const unsigned char *in)
-{
-  uint64_t result;
-  result = (uint64_t) in[0];
-  result |= ((uint64_t) in[1]) << 8;
-  result |= ((uint64_t) in[2]) << 16;
-  result |= ((uint64_t) in[3]) << 24;
-  return result;
-}
-
-/*
-Input:
-  a[0]+256*a[1]+...+256^31*a[31] = a
-  b[0]+256*b[1]+...+256^31*b[31] = b
-  c[0]+256*c[1]+...+256^31*c[31] = c
-
-Output:
-  s[0]+256*s[1]+...+256^31*s[31] = (ab+c) mod l
-  where l = 2^252 + 27742317777372353535851937790883648493.
-*/
-
-void sc_muladd(unsigned char *s,const unsigned char *a,const unsigned char *b,const unsigned char *c)
-{
-  int64_t a0 = 2097151 & load_3(a);
-  int64_t a1 = 2097151 & (load_4(a + 2) >> 5);
-  int64_t a2 = 2097151 & (load_3(a + 5) >> 2);
-  int64_t a3 = 2097151 & (load_4(a + 7) >> 7);
-  int64_t a4 = 2097151 & (load_4(a + 10) >> 4);
-  int64_t a5 = 2097151 & (load_3(a + 13) >> 1);
-  int64_t a6 = 2097151 & (load_4(a + 15) >> 6);
-  int64_t a7 = 2097151 & (load_3(a + 18) >> 3);
-  int64_t a8 = 2097151 & load_3(a + 21);
-  int64_t a9 = 2097151 & (load_4(a + 23) >> 5);
-  int64_t a10 = 2097151 & (load_3(a + 26) >> 2);
-  int64_t a11 = (load_4(a + 28) >> 7);
-  int64_t b0 = 2097151 & load_3(b);
-  int64_t b1 = 2097151 & (load_4(b + 2) >> 5);
-  int64_t b2 = 2097151 & (load_3(b + 5) >> 2);
-  int64_t b3 = 2097151 & (load_4(b + 7) >> 7);
-  int64_t b4 = 2097151 & (load_4(b + 10) >> 4);
-  int64_t b5 = 2097151 & (load_3(b + 13) >> 1);
-  int64_t b6 = 2097151 & (load_4(b + 15) >> 6);
-  int64_t b7 = 2097151 & (load_3(b + 18) >> 3);
-  int64_t b8 = 2097151 & load_3(b + 21);
-  int64_t b9 = 2097151 & (load_4(b + 23) >> 5);
-  int64_t b10 = 2097151 & (load_3(b + 26) >> 2);
-  int64_t b11 = (load_4(b + 28) >> 7);
-  int64_t c0 = 2097151 & load_3(c);
-  int64_t c1 = 2097151 & (load_4(c + 2) >> 5);
-  int64_t c2 = 2097151 & (load_3(c + 5) >> 2);
-  int64_t c3 = 2097151 & (load_4(c + 7) >> 7);
-  int64_t c4 = 2097151 & (load_4(c + 10) >> 4);
-  int64_t c5 = 2097151 & (load_3(c + 13) >> 1);
-  int64_t c6 = 2097151 & (load_4(c + 15) >> 6);
-  int64_t c7 = 2097151 & (load_3(c + 18) >> 3);
-  int64_t c8 = 2097151 & load_3(c + 21);
-  int64_t c9 = 2097151 & (load_4(c + 23) >> 5);
-  int64_t c10 = 2097151 & (load_3(c + 26) >> 2);
-  int64_t c11 = (load_4(c + 28) >> 7);
-  int64_t s0;
-  int64_t s1;
-  int64_t s2;
-  int64_t s3;
-  int64_t s4;
-  int64_t s5;
-  int64_t s6;
-  int64_t s7;
-  int64_t s8;
-  int64_t s9;
-  int64_t s10;
-  int64_t s11;
-  int64_t s12;
-  int64_t s13;
-  int64_t s14;
-  int64_t s15;
-  int64_t s16;
-  int64_t s17;
-  int64_t s18;
-  int64_t s19;
-  int64_t s20;
-  int64_t s21;
-  int64_t s22;
-  int64_t s23;
-  int64_t carry0;
-  int64_t carry1;
-  int64_t carry2;
-  int64_t carry3;
-  int64_t carry4;
-  int64_t carry5;
-  int64_t carry6;
-  int64_t carry7;
-  int64_t carry8;
-  int64_t carry9;
-  int64_t carry10;
-  int64_t carry11;
-  int64_t carry12;
-  int64_t carry13;
-  int64_t carry14;
-  int64_t carry15;
-  int64_t carry16;
-  int64_t carry17;
-  int64_t carry18;
-  int64_t carry19;
-  int64_t carry20;
-  int64_t carry21;
-  int64_t carry22;
-
-  s0 = c0 + a0*b0;
-  s1 = c1 + a0*b1 + a1*b0;
-  s2 = c2 + a0*b2 + a1*b1 + a2*b0;
-  s3 = c3 + a0*b3 + a1*b2 + a2*b1 + a3*b0;
-  s4 = c4 + a0*b4 + a1*b3 + a2*b2 + a3*b1 + a4*b0;
-  s5 = c5 + a0*b5 + a1*b4 + a2*b3 + a3*b2 + a4*b1 + a5*b0;
-  s6 = c6 + a0*b6 + a1*b5 + a2*b4 + a3*b3 + a4*b2 + a5*b1 + a6*b0;
-  s7 = c7 + a0*b7 + a1*b6 + a2*b5 + a3*b4 + a4*b3 + a5*b2 + a6*b1 + a7*b0;
-  s8 = c8 + a0*b8 + a1*b7 + a2*b6 + a3*b5 + a4*b4 + a5*b3 + a6*b2 + a7*b1 + a8*b0;
-  s9 = c9 + a0*b9 + a1*b8 + a2*b7 + a3*b6 + a4*b5 + a5*b4 + a6*b3 + a7*b2 + a8*b1 + a9*b0;
-  s10 = c10 + a0*b10 + a1*b9 + a2*b8 + a3*b7 + a4*b6 + a5*b5 + a6*b4 + a7*b3 + a8*b2 + a9*b1 + a10*b0;
-  s11 = c11 + a0*b11 + a1*b10 + a2*b9 + a3*b8 + a4*b7 + a5*b6 + a6*b5 + a7*b4 + a8*b3 + a9*b2 + a10*b1 + a11*b0;
-  s12 = a1*b11 + a2*b10 + a3*b9 + a4*b8 + a5*b7 + a6*b6 + a7*b5 + a8*b4 + a9*b3 + a10*b2 + a11*b1;
-  s13 = a2*b11 + a3*b10 + a4*b9 + a5*b8 + a6*b7 + a7*b6 + a8*b5 + a9*b4 + a10*b3 + a11*b2;
-  s14 = a3*b11 + a4*b10 + a5*b9 + a6*b8 + a7*b7 + a8*b6 + a9*b5 + a10*b4 + a11*b3;
-  s15 = a4*b11 + a5*b10 + a6*b9 + a7*b8 + a8*b7 + a9*b6 + a10*b5 + a11*b4;
-  s16 = a5*b11 + a6*b10 + a7*b9 + a8*b8 + a9*b7 + a10*b6 + a11*b5;
-  s17 = a6*b11 + a7*b10 + a8*b9 + a9*b8 + a10*b7 + a11*b6;
-  s18 = a7*b11 + a8*b10 + a9*b9 + a10*b8 + a11*b7;
-  s19 = a8*b11 + a9*b10 + a10*b9 + a11*b8;
-  s20 = a9*b11 + a10*b10 + a11*b9;
-  s21 = a10*b11 + a11*b10;
-  s22 = a11*b11;
-  s23 = 0;
-
-  carry0 = (s0 + (1<<20)) >> 21; s1 += carry0; s0 -= carry0 << 21;
-  carry2 = (s2 + (1<<20)) >> 21; s3 += carry2; s2 -= carry2 << 21;
-  carry4 = (s4 + (1<<20)) >> 21; s5 += carry4; s4 -= carry4 << 21;
-  carry6 = (s6 + (1<<20)) >> 21; s7 += carry6; s6 -= carry6 << 21;
-  carry8 = (s8 + (1<<20)) >> 21; s9 += carry8; s8 -= carry8 << 21;
-  carry10 = (s10 + (1<<20)) >> 21; s11 += carry10; s10 -= carry10 << 21;
-  carry12 = (s12 + (1<<20)) >> 21; s13 += carry12; s12 -= carry12 << 21;
-  carry14 = (s14 + (1<<20)) >> 21; s15 += carry14; s14 -= carry14 << 21;
-  carry16 = (s16 + (1<<20)) >> 21; s17 += carry16; s16 -= carry16 << 21;
-  carry18 = (s18 + (1<<20)) >> 21; s19 += carry18; s18 -= carry18 << 21;
-  carry20 = (s20 + (1<<20)) >> 21; s21 += carry20; s20 -= carry20 << 21;
-  carry22 = (s22 + (1<<20)) >> 21; s23 += carry22; s22 -= carry22 << 21;
-
-  carry1 = (s1 + (1<<20)) >> 21; s2 += carry1; s1 -= carry1 << 21;
-  carry3 = (s3 + (1<<20)) >> 21; s4 += carry3; s3 -= carry3 << 21;
-  carry5 = (s5 + (1<<20)) >> 21; s6 += carry5; s5 -= carry5 << 21;
-  carry7 = (s7 + (1<<20)) >> 21; s8 += carry7; s7 -= carry7 << 21;
-  carry9 = (s9 + (1<<20)) >> 21; s10 += carry9; s9 -= carry9 << 21;
-  carry11 = (s11 + (1<<20)) >> 21; s12 += carry11; s11 -= carry11 << 21;
-  carry13 = (s13 + (1<<20)) >> 21; s14 += carry13; s13 -= carry13 << 21;
-  carry15 = (s15 + (1<<20)) >> 21; s16 += carry15; s15 -= carry15 << 21;
-  carry17 = (s17 + (1<<20)) >> 21; s18 += carry17; s17 -= carry17 << 21;
-  carry19 = (s19 + (1<<20)) >> 21; s20 += carry19; s19 -= carry19 << 21;
-  carry21 = (s21 + (1<<20)) >> 21; s22 += carry21; s21 -= carry21 << 21;
-
-  s11 += s23 * 666643;
-  s12 += s23 * 470296;
-  s13 += s23 * 654183;
-  s14 -= s23 * 997805;
-  s15 += s23 * 136657;
-  s16 -= s23 * 683901;
-  s23 = 0;
-
-  s10 += s22 * 666643;
-  s11 += s22 * 470296;
-  s12 += s22 * 654183;
-  s13 -= s22 * 997805;
-  s14 += s22 * 136657;
-  s15 -= s22 * 683901;
-  s22 = 0;
-
-  s9 += s21 * 666643;
-  s10 += s21 * 470296;
-  s11 += s21 * 654183;
-  s12 -= s21 * 997805;
-  s13 += s21 * 136657;
-  s14 -= s21 * 683901;
-  s21 = 0;
-
-  s8 += s20 * 666643;
-  s9 += s20 * 470296;
-  s10 += s20 * 654183;
-  s11 -= s20 * 997805;
-  s12 += s20 * 136657;
-  s13 -= s20 * 683901;
-  s20 = 0;
-
-  s7 += s19 * 666643;
-  s8 += s19 * 470296;
-  s9 += s19 * 654183;
-  s10 -= s19 * 997805;
-  s11 += s19 * 136657;
-  s12 -= s19 * 683901;
-  s19 = 0;
-
-  s6 += s18 * 666643;
-  s7 += s18 * 470296;
-  s8 += s18 * 654183;
-  s9 -= s18 * 997805;
-  s10 += s18 * 136657;
-  s11 -= s18 * 683901;
-  s18 = 0;
-
-  carry6 = (s6 + (1<<20)) >> 21; s7 += carry6; s6 -= carry6 << 21;
-  carry8 = (s8 + (1<<20)) >> 21; s9 += carry8; s8 -= carry8 << 21;
-  carry10 = (s10 + (1<<20)) >> 21; s11 += carry10; s10 -= carry10 << 21;
-  carry12 = (s12 + (1<<20)) >> 21; s13 += carry12; s12 -= carry12 << 21;
-  carry14 = (s14 + (1<<20)) >> 21; s15 += carry14; s14 -= carry14 << 21;
-  carry16 = (s16 + (1<<20)) >> 21; s17 += carry16; s16 -= carry16 << 21;
-
-  carry7 = (s7 + (1<<20)) >> 21; s8 += carry7; s7 -= carry7 << 21;
-  carry9 = (s9 + (1<<20)) >> 21; s10 += carry9; s9 -= carry9 << 21;
-  carry11 = (s11 + (1<<20)) >> 21; s12 += carry11; s11 -= carry11 << 21;
-  carry13 = (s13 + (1<<20)) >> 21; s14 += carry13; s13 -= carry13 << 21;
-  carry15 = (s15 + (1<<20)) >> 21; s16 += carry15; s15 -= carry15 << 21;
-
-  s5 += s17 * 666643;
-  s6 += s17 * 470296;
-  s7 += s17 * 654183;
-  s8 -= s17 * 997805;
-  s9 += s17 * 136657;
-  s10 -= s17 * 683901;
-  s17 = 0;
-
-  s4 += s16 * 666643;
-  s5 += s16 * 470296;
-  s6 += s16 * 654183;
-  s7 -= s16 * 997805;
-  s8 += s16 * 136657;
-  s9 -= s16 * 683901;
-  s16 = 0;
-
-  s3 += s15 * 666643;
-  s4 += s15 * 470296;
-  s5 += s15 * 654183;
-  s6 -= s15 * 997805;
-  s7 += s15 * 136657;
-  s8 -= s15 * 683901;
-  s15 = 0;
-
-  s2 += s14 * 666643;
-  s3 += s14 * 470296;
-  s4 += s14 * 654183;
-  s5 -= s14 * 997805;
-  s6 += s14 * 136657;
-  s7 -= s14 * 683901;
-  s14 = 0;
-
-  s1 += s13 * 666643;
-  s2 += s13 * 470296;
-  s3 += s13 * 654183;
-  s4 -= s13 * 997805;
-  s5 += s13 * 136657;
-  s6 -= s13 * 683901;
-  s13 = 0;
-
-  s0 += s12 * 666643;
-  s1 += s12 * 470296;
-  s2 += s12 * 654183;
-  s3 -= s12 * 997805;
-  s4 += s12 * 136657;
-  s5 -= s12 * 683901;
-  s12 = 0;
-
-  carry0 = (s0 + (1<<20)) >> 21; s1 += carry0; s0 -= carry0 << 21;
-  carry2 = (s2 + (1<<20)) >> 21; s3 += carry2; s2 -= carry2 << 21;
-  carry4 = (s4 + (1<<20)) >> 21; s5 += carry4; s4 -= carry4 << 21;
-  carry6 = (s6 + (1<<20)) >> 21; s7 += carry6; s6 -= carry6 << 21;
-  carry8 = (s8 + (1<<20)) >> 21; s9 += carry8; s8 -= carry8 << 21;
-  carry10 = (s10 + (1<<20)) >> 21; s11 += carry10; s10 -= carry10 << 21;
-
-  carry1 = (s1 + (1<<20)) >> 21; s2 += carry1; s1 -= carry1 << 21;
-  carry3 = (s3 + (1<<20)) >> 21; s4 += carry3; s3 -= carry3 << 21;
-  carry5 = (s5 + (1<<20)) >> 21; s6 += carry5; s5 -= carry5 << 21;
-  carry7 = (s7 + (1<<20)) >> 21; s8 += carry7; s7 -= carry7 << 21;
-  carry9 = (s9 + (1<<20)) >> 21; s10 += carry9; s9 -= carry9 << 21;
-  carry11 = (s11 + (1<<20)) >> 21; s12 += carry11; s11 -= carry11 << 21;
-
-  s0 += s12 * 666643;
-  s1 += s12 * 470296;
-  s2 += s12 * 654183;
-  s3 -= s12 * 997805;
-  s4 += s12 * 136657;
-  s5 -= s12 * 683901;
-  s12 = 0;
-
-  carry0 = s0 >> 21; s1 += carry0; s0 -= carry0 << 21;
-  carry1 = s1 >> 21; s2 += carry1; s1 -= carry1 << 21;
-  carry2 = s2 >> 21; s3 += carry2; s2 -= carry2 << 21;
-  carry3 = s3 >> 21; s4 += carry3; s3 -= carry3 << 21;
-  carry4 = s4 >> 21; s5 += carry4; s4 -= carry4 << 21;
-  carry5 = s5 >> 21; s6 += carry5; s5 -= carry5 << 21;
-  carry6 = s6 >> 21; s7 += carry6; s6 -= carry6 << 21;
-  carry7 = s7 >> 21; s8 += carry7; s7 -= carry7 << 21;
-  carry8 = s8 >> 21; s9 += carry8; s8 -= carry8 << 21;
-  carry9 = s9 >> 21; s10 += carry9; s9 -= carry9 << 21;
-  carry10 = s10 >> 21; s11 += carry10; s10 -= carry10 << 21;
-  carry11 = s11 >> 21; s12 += carry11; s11 -= carry11 << 21;
-
-  s0 += s12 * 666643;
-  s1 += s12 * 470296;
-  s2 += s12 * 654183;
-  s3 -= s12 * 997805;
-  s4 += s12 * 136657;
-  s5 -= s12 * 683901;
-  s12 = 0;
-
-  carry0 = s0 >> 21; s1 += carry0; s0 -= carry0 << 21;
-  carry1 = s1 >> 21; s2 += carry1; s1 -= carry1 << 21;
-  carry2 = s2 >> 21; s3 += carry2; s2 -= carry2 << 21;
-  carry3 = s3 >> 21; s4 += carry3; s3 -= carry3 << 21;
-  carry4 = s4 >> 21; s5 += carry4; s4 -= carry4 << 21;
-  carry5 = s5 >> 21; s6 += carry5; s5 -= carry5 << 21;
-  carry6 = s6 >> 21; s7 += carry6; s6 -= carry6 << 21;
-  carry7 = s7 >> 21; s8 += carry7; s7 -= carry7 << 21;
-  carry8 = s8 >> 21; s9 += carry8; s8 -= carry8 << 21;
-  carry9 = s9 >> 21; s10 += carry9; s9 -= carry9 << 21;
-  carry10 = s10 >> 21; s11 += carry10; s10 -= carry10 << 21;
-
-  s[0] = (unsigned char) (s0 >> 0);
-  s[1] = (unsigned char) (s0 >> 8);
-  s[2] = (unsigned char) ((s0 >> 16) | (s1 << 5));
-  s[3] = (unsigned char) (s1 >> 3);
-  s[4] = (unsigned char) (s1 >> 11);
-  s[5] = (unsigned char) ((s1 >> 19) | (s2 << 2));
-  s[6] = (unsigned char) (s2 >> 6);
-  s[7] = (unsigned char) ((s2 >> 14) | (s3 << 7));
-  s[8] = (unsigned char) (s3 >> 1);
-  s[9] = (unsigned char) (s3 >> 9);
-  s[10] = (unsigned char) ((s3 >> 17) | (s4 << 4));
-  s[11] = (unsigned char) (s4 >> 4);
-  s[12] = (unsigned char) (s4 >> 12);
-  s[13] = (unsigned char) ((s4 >> 20) | (s5 << 1));
-  s[14] = (unsigned char) (s5 >> 7);
-  s[15] = (unsigned char) ((s5 >> 15) | (s6 << 6));
-  s[16] = (unsigned char) (s6 >> 2);
-  s[17] = (unsigned char) (s6 >> 10);
-  s[18] = (unsigned char) ((s6 >> 18) | (s7 << 3));
-  s[19] = (unsigned char) (s7 >> 5);
-  s[20] = (unsigned char) (s7 >> 13);
-  s[21] = (unsigned char) (s8 >> 0);
-  s[22] = (unsigned char) (s8 >> 8);
-  s[23] = (unsigned char) ((s8 >> 16) | (s9 << 5));
-  s[24] = (unsigned char) (s9 >> 3);
-  s[25] = (unsigned char) (s9 >> 11);
-  s[26] = (unsigned char) ((s9 >> 19) | (s10 << 2));
-  s[27] = (unsigned char) (s10 >> 6);
-  s[28] = (unsigned char) ((s10 >> 14) | (s11 << 7));
-  s[29] = (unsigned char) (s11 >> 1);
-  s[30] = (unsigned char) (s11 >> 9);
-  s[31] = (unsigned char) (s11 >> 17);
-}
diff --git a/sc_reduce.c b/sc_reduce.c
deleted file mode 100644
index 312e537..0000000
--- a/sc_reduce.c
+++ /dev/null
@@ -1,273 +0,0 @@
-#include "sc.h"
-#include "pstdint.h"
-
-static uint64_t load_3(const unsigned char *in)
-{
-  uint64_t result;
-  result = (uint64_t) in[0];
-  result |= ((uint64_t) in[1]) << 8;
-  result |= ((uint64_t) in[2]) << 16;
-  return result;
-}
-
-static uint64_t load_4(const unsigned char *in)
-{
-  uint64_t result;
-  result = (uint64_t) in[0];
-  result |= ((uint64_t) in[1]) << 8;
-  result |= ((uint64_t) in[2]) << 16;
-  result |= ((uint64_t) in[3]) << 24;
-  return result;
-}
-
-/*
-Input:
-  s[0]+256*s[1]+...+256^63*s[63] = s
-
-Output:
-  s[0]+256*s[1]+...+256^31*s[31] = s mod l
-  where l = 2^252 + 27742317777372353535851937790883648493.
-  Overwrites s in place.
-*/
-
-void sc_reduce(unsigned char *s)
-{
-  int64_t s0 = 2097151 & load_3(s);
-  int64_t s1 = 2097151 & (load_4(s + 2) >> 5);
-  int64_t s2 = 2097151 & (load_3(s + 5) >> 2);
-  int64_t s3 = 2097151 & (load_4(s + 7) >> 7);
-  int64_t s4 = 2097151 & (load_4(s + 10) >> 4);
-  int64_t s5 = 2097151 & (load_3(s + 13) >> 1);
-  int64_t s6 = 2097151 & (load_4(s + 15) >> 6);
-  int64_t s7 = 2097151 & (load_3(s + 18) >> 3);
-  int64_t s8 = 2097151 & load_3(s + 21);
-  int64_t s9 = 2097151 & (load_4(s + 23) >> 5);
-  int64_t s10 = 2097151 & (load_3(s + 26) >> 2);
-  int64_t s11 = 2097151 & (load_4(s + 28) >> 7);
-  int64_t s12 = 2097151 & (load_4(s + 31) >> 4);
-  int64_t s13 = 2097151 & (load_3(s + 34) >> 1);
-  int64_t s14 = 2097151 & (load_4(s + 36) >> 6);
-  int64_t s15 = 2097151 & (load_3(s + 39) >> 3);
-  int64_t s16 = 2097151 & load_3(s + 42);
-  int64_t s17 = 2097151 & (load_4(s + 44) >> 5);
-  int64_t s18 = 2097151 & (load_3(s + 47) >> 2);
-  int64_t s19 = 2097151 & (load_4(s + 49) >> 7);
-  int64_t s20 = 2097151 & (load_4(s + 52) >> 4);
-  int64_t s21 = 2097151 & (load_3(s + 55) >> 1);
-  int64_t s22 = 2097151 & (load_4(s + 57) >> 6);
-  int64_t s23 = (load_4(s + 60) >> 3);
-  int64_t carry0;
-  int64_t carry1;
-  int64_t carry2;
-  int64_t carry3;
-  int64_t carry4;
-  int64_t carry5;
-  int64_t carry6;
-  int64_t carry7;
-  int64_t carry8;
-  int64_t carry9;
-  int64_t carry10;
-  int64_t carry11;
-  int64_t carry12;
-  int64_t carry13;
-  int64_t carry14;
-  int64_t carry15;
-  int64_t carry16;
-
-  s11 += s23 * 666643;
-  s12 += s23 * 470296;
-  s13 += s23 * 654183;
-  s14 -= s23 * 997805;
-  s15 += s23 * 136657;
-  s16 -= s23 * 683901;
-  s23 = 0;
-
-  s10 += s22 * 666643;
-  s11 += s22 * 470296;
-  s12 += s22 * 654183;
-  s13 -= s22 * 997805;
-  s14 += s22 * 136657;
-  s15 -= s22 * 683901;
-  s22 = 0;
-
-  s9 += s21 * 666643;
-  s10 += s21 * 470296;
-  s11 += s21 * 654183;
-  s12 -= s21 * 997805;
-  s13 += s21 * 136657;
-  s14 -= s21 * 683901;
-  s21 = 0;
-
-  s8 += s20 * 666643;
-  s9 += s20 * 470296;
-  s10 += s20 * 654183;
-  s11 -= s20 * 997805;
-  s12 += s20 * 136657;
-  s13 -= s20 * 683901;
-  s20 = 0;
-
-  s7 += s19 * 666643;
-  s8 += s19 * 470296;
-  s9 += s19 * 654183;
-  s10 -= s19 * 997805;
-  s11 += s19 * 136657;
-  s12 -= s19 * 683901;
-  s19 = 0;
-
-  s6 += s18 * 666643;
-  s7 += s18 * 470296;
-  s8 += s18 * 654183;
-  s9 -= s18 * 997805;
-  s10 += s18 * 136657;
-  s11 -= s18 * 683901;
-  s18 = 0;
-
-  carry6 = (s6 + (1<<20)) >> 21; s7 += carry6; s6 -= carry6 << 21;
-  carry8 = (s8 + (1<<20)) >> 21; s9 += carry8; s8 -= carry8 << 21;
-  carry10 = (s10 + (1<<20)) >> 21; s11 += carry10; s10 -= carry10 << 21;
-  carry12 = (s12 + (1<<20)) >> 21; s13 += carry12; s12 -= carry12 << 21;
-  carry14 = (s14 + (1<<20)) >> 21; s15 += carry14; s14 -= carry14 << 21;
-  carry16 = (s16 + (1<<20)) >> 21; s17 += carry16; s16 -= carry16 << 21;
-
-  carry7 = (s7 + (1<<20)) >> 21; s8 += carry7; s7 -= carry7 << 21;
-  carry9 = (s9 + (1<<20)) >> 21; s10 += carry9; s9 -= carry9 << 21;
-  carry11 = (s11 + (1<<20)) >> 21; s12 += carry11; s11 -= carry11 << 21;
-  carry13 = (s13 + (1<<20)) >> 21; s14 += carry13; s13 -= carry13 << 21;
-  carry15 = (s15 + (1<<20)) >> 21; s16 += carry15; s15 -= carry15 << 21;
-
-  s5 += s17 * 666643;
-  s6 += s17 * 470296;
-  s7 += s17 * 654183;
-  s8 -= s17 * 997805;
-  s9 += s17 * 136657;
-  s10 -= s17 * 683901;
-  s17 = 0;
-
-  s4 += s16 * 666643;
-  s5 += s16 * 470296;
-  s6 += s16 * 654183;
-  s7 -= s16 * 997805;
-  s8 += s16 * 136657;
-  s9 -= s16 * 683901;
-  s16 = 0;
-
-  s3 += s15 * 666643;
-  s4 += s15 * 470296;
-  s5 += s15 * 654183;
-  s6 -= s15 * 997805;
-  s7 += s15 * 136657;
-  s8 -= s15 * 683901;
-  s15 = 0;
-
-  s2 += s14 * 666643;
-  s3 += s14 * 470296;
-  s4 += s14 * 654183;
-  s5 -= s14 * 997805;
-  s6 += s14 * 136657;
-  s7 -= s14 * 683901;
-  s14 = 0;
-
-  s1 += s13 * 666643;
-  s2 += s13 * 470296;
-  s3 += s13 * 654183;
-  s4 -= s13 * 997805;
-  s5 += s13 * 136657;
-  s6 -= s13 * 683901;
-  s13 = 0;
-
-  s0 += s12 * 666643;
-  s1 += s12 * 470296;
-  s2 += s12 * 654183;
-  s3 -= s12 * 997805;
-  s4 += s12 * 136657;
-  s5 -= s12 * 683901;
-  s12 = 0;
-
-  carry0 = (s0 + (1<<20)) >> 21; s1 += carry0; s0 -= carry0 << 21;
-  carry2 = (s2 + (1<<20)) >> 21; s3 += carry2; s2 -= carry2 << 21;
-  carry4 = (s4 + (1<<20)) >> 21; s5 += carry4; s4 -= carry4 << 21;
-  carry6 = (s6 + (1<<20)) >> 21; s7 += carry6; s6 -= carry6 << 21;
-  carry8 = (s8 + (1<<20)) >> 21; s9 += carry8; s8 -= carry8 << 21;
-  carry10 = (s10 + (1<<20)) >> 21; s11 += carry10; s10 -= carry10 << 21;
-
-  carry1 = (s1 + (1<<20)) >> 21; s2 += carry1; s1 -= carry1 << 21;
-  carry3 = (s3 + (1<<20)) >> 21; s4 += carry3; s3 -= carry3 << 21;
-  carry5 = (s5 + (1<<20)) >> 21; s6 += carry5; s5 -= carry5 << 21;
-  carry7 = (s7 + (1<<20)) >> 21; s8 += carry7; s7 -= carry7 << 21;
-  carry9 = (s9 + (1<<20)) >> 21; s10 += carry9; s9 -= carry9 << 21;
-  carry11 = (s11 + (1<<20)) >> 21; s12 += carry11; s11 -= carry11 << 21;
-
-  s0 += s12 * 666643;
-  s1 += s12 * 470296;
-  s2 += s12 * 654183;
-  s3 -= s12 * 997805;
-  s4 += s12 * 136657;
-  s5 -= s12 * 683901;
-  s12 = 0;
-
-  carry0 = s0 >> 21; s1 += carry0; s0 -= carry0 << 21;
-  carry1 = s1 >> 21; s2 += carry1; s1 -= carry1 << 21;
-  carry2 = s2 >> 21; s3 += carry2; s2 -= carry2 << 21;
-  carry3 = s3 >> 21; s4 += carry3; s3 -= carry3 << 21;
-  carry4 = s4 >> 21; s5 += carry4; s4 -= carry4 << 21;
-  carry5 = s5 >> 21; s6 += carry5; s5 -= carry5 << 21;
-  carry6 = s6 >> 21; s7 += carry6; s6 -= carry6 << 21;
-  carry7 = s7 >> 21; s8 += carry7; s7 -= carry7 << 21;
-  carry8 = s8 >> 21; s9 += carry8; s8 -= carry8 << 21;
-  carry9 = s9 >> 21; s10 += carry9; s9 -= carry9 << 21;
-  carry10 = s10 >> 21; s11 += carry10; s10 -= carry10 << 21;
-  carry11 = s11 >> 21; s12 += carry11; s11 -= carry11 << 21;
-
-  s0 += s12 * 666643;
-  s1 += s12 * 470296;
-  s2 += s12 * 654183;
-  s3 -= s12 * 997805;
-  s4 += s12 * 136657;
-  s5 -= s12 * 683901;
-  s12 = 0;
-
-  carry0 = s0 >> 21; s1 += carry0; s0 -= carry0 << 21;
-  carry1 = s1 >> 21; s2 += carry1; s1 -= carry1 << 21;
-  carry2 = s2 >> 21; s3 += carry2; s2 -= carry2 << 21;
-  carry3 = s3 >> 21; s4 += carry3; s3 -= carry3 << 21;
-  carry4 = s4 >> 21; s5 += carry4; s4 -= carry4 << 21;
-  carry5 = s5 >> 21; s6 += carry5; s5 -= carry5 << 21;
-  carry6 = s6 >> 21; s7 += carry6; s6 -= carry6 << 21;
-  carry7 = s7 >> 21; s8 += carry7; s7 -= carry7 << 21;
-  carry8 = s8 >> 21; s9 += carry8; s8 -= carry8 << 21;
-  carry9 = s9 >> 21; s10 += carry9; s9 -= carry9 << 21;
-  carry10 = s10 >> 21; s11 += carry10; s10 -= carry10 << 21;
-
-  s[0] = (unsigned char) (s0 >> 0);
-  s[1] = (unsigned char) (s0 >> 8);
-  s[2] = (unsigned char) ((s0 >> 16) | (s1 << 5));
-  s[3] = (unsigned char) (s1 >> 3);
-  s[4] = (unsigned char) (s1 >> 11);
-  s[5] = (unsigned char) ((s1 >> 19) | (s2 << 2));
-  s[6] = (unsigned char) (s2 >> 6);
-  s[7] = (unsigned char) ((s2 >> 14) | (s3 << 7));
-  s[8] = (unsigned char) (s3 >> 1);
-  s[9] = (unsigned char) (s3 >> 9);
-  s[10] = (unsigned char) ((s3 >> 17) | (s4 << 4));
-  s[11] = (unsigned char) (s4 >> 4);
-  s[12] = (unsigned char) (s4 >> 12);
-  s[13] = (unsigned char) ((s4 >> 20) | (s5 << 1));
-  s[14] = (unsigned char) (s5 >> 7);
-  s[15] = (unsigned char) ((s5 >> 15) | (s6 << 6));
-  s[16] = (unsigned char) (s6 >> 2);
-  s[17] = (unsigned char) (s6 >> 10);
-  s[18] = (unsigned char) ((s6 >> 18) | (s7 << 3));
-  s[19] = (unsigned char) (s7 >> 5);
-  s[20] = (unsigned char) (s7 >> 13);
-  s[21] = (unsigned char) (s8 >> 0);
-  s[22] = (unsigned char) (s8 >> 8);
-  s[23] = (unsigned char) ((s8 >> 16) | (s9 << 5));
-  s[24] = (unsigned char) (s9 >> 3);
-  s[25] = (unsigned char) (s9 >> 11);
-  s[26] = (unsigned char) ((s9 >> 19) | (s10 << 2));
-  s[27] = (unsigned char) (s10 >> 6);
-  s[28] = (unsigned char) ((s10 >> 14) | (s11 << 7));
-  s[29] = (unsigned char) (s11 >> 1);
-  s[30] = (unsigned char) (s11 >> 9);
-  s[31] = (unsigned char) (s11 >> 17);
-}
diff --git a/test.c b/test.c
index 2ff5f25..282edd4 100644
--- a/test.c
+++ b/test.c
@@ -6,10 +6,17 @@
 char msg[] = "Hello World";
 
 int main(int argc, char *argv[]) {
-    unsigned char sk[64], vk[32];
+    unsigned char sk[64], vk[32], seed[32];
     unsigned char *sigmsg;
 	FILE *f;
 
+    ed25519_create_seed(seed);
+
+    f = fopen("seed.txt", "wb");
+    fwrite(seed, 32, 1, f);
+    fclose(f);
+
+
     int ret;
     ed25519_create_keypair(vk, sk, "01234567890123456789012345678901");
 
diff --git a/verify.c b/verify.c
index b23e451..de5e7fd 100644
--- a/verify.c
+++ b/verify.c
@@ -1,38 +1,33 @@
-int crypto_verify_32(const unsigned char *x, const unsigned char *y)
+#include "ed25519.h"
+#include "sha512.h"
+#include "ge.h"
+#include "sc.h"
+#include "consttime_cmp.h"
+
+int ed25519_verify(const unsigned char *signature, const unsigned char *message, unsigned int message_len, const unsigned char *verify_key)
 {
-  unsigned int differentbits = 0;
-#define F(i) differentbits |= x[i] ^ y[i];
-  F(0)
-  F(1)
-  F(2)
-  F(3)
-  F(4)
-  F(5)
-  F(6)
-  F(7)
-  F(8)
-  F(9)
-  F(10)
-  F(11)
-  F(12)
-  F(13)
-  F(14)
-  F(15)
-  F(16)
-  F(17)
-  F(18)
-  F(19)
-  F(20)
-  F(21)
-  F(22)
-  F(23)
-  F(24)
-  F(25)
-  F(26)
-  F(27)
-  F(28)
-  F(29)
-  F(30)
-  F(31)
-  return (1 & ((differentbits - 1) >> 8)) - 1;
-}
\ No newline at end of file
+  unsigned char h[64];
+  unsigned char checker[32];
+  sha512_ctx hash;
+  ge_p3 A;
+  ge_p2 R;
+
+  if (signature[63] & 224) return -1;
+  if (ge_frombytes_negate_vartime(&A,verify_key) != 0) return -1;
+
+  sha512_init(&hash);
+  sha512_update(&hash, signature, 32);
+  sha512_update(&hash, verify_key, 32);
+  sha512_update(&hash, message, message_len);
+  sha512_final(&hash, h);
+
+  sc_reduce(h);
+
+  ge_double_scalarmult_vartime(&R,h,&A,signature + 32);
+  ge_tobytes(checker, &R);
+  if (consttime_cmp_32(checker, signature) != 0) {
+    return -1;
+  }
+
+  return 0;
+}
diff --git a/verify.h b/verify.h
index d02353f..d3c4581 100644
--- a/verify.h
+++ b/verify.h
@@ -1 +1,6 @@
-int crypto_verify_32(const unsigned char *x,const unsigned char *y);
\ No newline at end of file
+#ifndef CONSTTIME_CMP_H
+#define CONSTTIME_CMP_H
+
+int consttime_cmp_32(const unsigned char *x, const unsigned char *y);
+
+#endif
\ No newline at end of file