diff options
Diffstat (limited to 'src/util/crypto.c')
| -rw-r--r-- | src/util/crypto.c | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/src/util/crypto.c b/src/util/crypto.c index 771744c7..caeda3ff 100644 --- a/src/util/crypto.c +++ b/src/util/crypto.c @@ -194,7 +194,20 @@ TALER_setup_fresh_coin (const struct TALER_TransferSecretP *secret_seed, "taler-coin-derivation", strlen ("taler-coin-derivation"), NULL, 0)); - /* FIXME: twiddle the bits of the private key */ + + /* Taken from like 170-172 of libgcrypt/cipher/ecc.c + * We note that libgcrypt stores the private key in the reverse order + * from many Ed25519 implementatons. */ + fc->coin_priv[0] &= 0x7f; /* Clear bit 255. */ + fc->coin_priv[0] |= 0x40; /* Set bit 254. */ + fc->coin_priv[31] &= 0xf8; /* Clear bits 2..0 so that d mod 8 == 0 */ + + /* FIXME: Run GNUNET_CRYPTO_ecdhe_key_create several times and inspect + * the output to verify that the same bits are set and cleared. + * Is it worth also adding a test case that runs gcry_pk_testkey on + * this key after first parsing it into libgcrypt's s-expression mess + * ala decode_private_eddsa_key from gnunet/src/util/crypto_ecc.c? + * It'd run check_secret_key but not test_keys from libgcrypt/cipher/ecc.c */ } |