1 files changed, 103 insertions, 0 deletions

diff --git a/nacl/crypto_sign/edwards25519sha512batch/ref/sign.c b/nacl/crypto_sign/edwards25519sha512batch/ref/sign.c
new file mode 100644
index 00000000..f40e548b
--- /dev/null
+++ b/nacl/crypto_sign/edwards25519sha512batch/ref/sign.c
@@ -0,0 +1,103 @@
+#include "api.h"
+#include "crypto_sign.h"
+#include "crypto_hash_sha512.h"
+#include "randombytes.h"
+#include "crypto_verify_32.h"
+
+#include "ge25519.h"
+
+int crypto_sign_keypair(
+    unsigned char *pk,
+    unsigned char *sk
+    )
+{
+  sc25519 scsk;
+  ge25519 gepk;
+
+  randombytes(sk, 32);
+  crypto_hash_sha512(sk, sk, 32);
+  sk[0] &= 248;
+  sk[31] &= 127;
+  sk[31] |= 64;
+
+  sc25519_from32bytes(&scsk,sk);
+  
+  ge25519_scalarmult_base(&gepk, &scsk);
+  ge25519_pack(pk, &gepk);
+  return 0;
+}
+
+int crypto_sign(
+    unsigned char *sm,unsigned long long *smlen,
+    const unsigned char *m,unsigned long long mlen,
+    const unsigned char *sk
+    )
+{
+  sc25519 sck, scs, scsk;
+  ge25519 ger;
+  unsigned char r[32];
+  unsigned char s[32];
+  unsigned long long i;
+  unsigned char hmg[crypto_hash_sha512_BYTES];
+  unsigned char hmr[crypto_hash_sha512_BYTES];
+
+  *smlen = mlen+64;
+  for(i=0;i<mlen;i++)
+    sm[32 + i] = m[i];
+  for(i=0;i<32;i++)
+    sm[i] = sk[32+i];
+  crypto_hash_sha512(hmg, sm, mlen+32); /* Generate k as h(m,sk[32],...,sk[63]) */
+
+  sc25519_from64bytes(&sck, hmg);
+  ge25519_scalarmult_base(&ger, &sck);
+  ge25519_pack(r, &ger);
+  
+  for(i=0;i<32;i++)
+    sm[i] = r[i];
+
+  crypto_hash_sha512(hmr, sm, mlen+32); /* Compute h(m,r) */
+  sc25519_from64bytes(&scs, hmr);
+  sc25519_mul(&scs, &scs, &sck);
+  
+  sc25519_from32bytes(&scsk, sk);
+  sc25519_add(&scs, &scs, &scsk);
+
+  sc25519_to32bytes(s,&scs); /* cat s */
+  for(i=0;i<32;i++)
+    sm[mlen+32+i] = s[i]; 
+
+  return 0;
+}
+
+int crypto_sign_open(
+    unsigned char *m,unsigned long long *mlen,
+    const unsigned char *sm,unsigned long long smlen,
+    const unsigned char *pk
+    )
+{
+  int i;
+  unsigned char t1[32], t2[32];
+  ge25519 get1, get2, gepk;
+  sc25519 schmr, scs;
+  unsigned char hmr[crypto_hash_sha512_BYTES];
+
+  if (ge25519_unpack_vartime(&get1, sm)) return -1;
+  if (ge25519_unpack_vartime(&gepk, pk)) return -1;
+
+  crypto_hash_sha512(hmr,sm,smlen-32);
+
+  sc25519_from64bytes(&schmr, hmr);
+  ge25519_scalarmult(&get1, &get1, &schmr);
+  ge25519_add(&get1, &get1, &gepk);
+  ge25519_pack(t1, &get1);
+
+  sc25519_from32bytes(&scs, &sm[smlen-32]);
+  ge25519_scalarmult_base(&get2, &scs);
+  ge25519_pack(t2, &get2);
+
+  for(i=0;i<smlen-64;i++)
+    m[i] = sm[i + 32];
+  *mlen = smlen-64;
+
+  return crypto_verify_32(t1, t2);
+}