ed25519.pas

   1 {$mode objfpc}
   2 UNIT ed25519;
   3 INTERFACE
   4
   5 type tKey32=packed array [0..31] of byte;
   6 type tKey64=packed array [0..63] of byte;
   7 type
   8  tPubKey=tKey32;
   9  tPrivKey=tKey64;
  10  tSig=tKey64;
  11
  12 (*procedure CreateSeed(out seed: tKey32);*)
  13 procedure CreatekeyPair(out pub:tPubKey; var priv:tPrivKey);
  14 procedure Sign(out signature:tSig; const message; len:LongWord; const pub:tPubKey; const priv:tPrivKey);
  15 function Verify(const signature:tSig; const message; len:LongWord; const pub:tPubKey):boolean;
  16 procedure SharedSecret(out shared:tKey32; const pub:tPubKey; const priv:tPrivKey);
  17
  18 IMPLEMENTATION
  19
  20 {$L ed25519/sc.o}
  21 {$L ed25519/fe.o}
  22 {$L ed25519/ge.o}
  23 {$L ed25519/sign.o}
  24 {$L ed25519/verify.o}
  25 {$L ed25519/key_exchange.o}
  26 {$L ed25519/sha512.o}
  27
  28 procedure ed25519_create_keypair(pub,priv,seed:pointer);
  29  cdecl;external;
  30 procedure ed25519_sign(sig,msg:pointer; len:LongWord; pub,priv:pointer);
  31  cdecl;external;
  32 function ed25519_verify(sig,msg:pointer; len:LongWord; pub:pointer):integer;
  33  cdecl;external;
  34 procedure ed25519_key_exchange(shared,pub,priv:pointer);
  35  cdecl;external;
  36
  37 type ge_p3=packed array [1..160] of byte; {opaque}
  38 procedure ge_scalarmult_base(h,a:pointer); cdecl;external;
  39 procedure ge_p3_tobytes(s, h:pointer); cdecl;external;
  40
  41 procedure CreateKeyPair(out pub:tPubKey; var priv:tPrivKey);
  42  var A:ge_p3;
  43  begin
  44  priv[ 0] := priv[ 0] and 248;
  45  priv[31] := priv[31] and  63;
  46  priv[31] := priv[31]  or  64;
  47  ge_scalarmult_base(@A, @priv);
  48  ge_p3_tobytes(@pub, @A);
  49 end;
  50
  51 procedure Sign(out signature:tSig; const message; len:LongWord; const pub:tPubKey; const priv:tPrivKey);
  52  begin
  53  ed25519_sign(@signature,@message,len,@pub,@priv);
  54 end;
  55
  56 function Verify(const signature:tSig; const message; len:LongWord; const pub:tPubKey):boolean;
  57  begin
  58  Verify:=ed25519_verify(@signature,@message,len,@pub)=1;
  59 end;
  60
  61 procedure SharedSecret(out shared:tKey32; const pub:tPubKey; const priv:tPrivKey);
  62  begin
  63  ed25519_key_exchange(@shared,@pub,@priv);
  64 end;
  65
  66 END.