void serialize_point(struct gotr_point *buf, const size_t len, const gcry_mpi_point_t p)
{
gcry_sexp_t s;
gcry_ctx_t ctx;
gcry_error_t rc;
gcry_mpi_t q;
gotr_assert(buf && len >= SERIALIZED_POINT_LEN);
rc = gcry_sexp_build(&s, NULL, "(public-key(ecc(curve " CURVE ")))");
gotr_assert_gpgerr(rc);
gotr_assert(NULL != s);
rc = gcry_mpi_ec_new(&ctx, s, NULL);
gotr_assert_gpgerr(rc);
gcry_sexp_release(s);
rc = gcry_mpi_ec_set_point("q", p, ctx);
gotr_assert_gpgerr(rc);
q = gcry_mpi_ec_get_mpi("q@eddsa", ctx, 0);
gotr_assert(NULL != q);
gcry_ctx_release(ctx);
gotr_mpi_print_unsigned(buf, len, q);
gcry_mpi_release(q);
}
static void
extract_pk (gcry_mpi_point_t pt,
gcry_ctx_t ctx,
struct GNUNET_PeerIdentity *pid)
{
gcry_mpi_t q_y;
GNUNET_assert (0 == gcry_mpi_ec_set_point ("q", pt, ctx));
q_y = gcry_mpi_ec_get_mpi ("q@eddsa", ctx, 0);
GNUNET_assert (q_y);
GNUNET_CRYPTO_mpi_print_unsigned (pid->public_key.q_y,
sizeof (pid->public_key.q_y),
q_y);
gcry_mpi_release (q_y);
}
/**
* Convert point value to binary representation.
*
* @param edc calculation context for ECC operations
* @param point computational point representation
* @param[out] bin binary point representation
*/
void
GNUNET_CRYPTO_ecc_point_to_bin (struct GNUNET_CRYPTO_EccDlogContext *edc,
gcry_mpi_point_t point,
struct GNUNET_CRYPTO_EccPoint *bin)
{
gcry_mpi_t q_y;
GNUNET_assert (0 == gcry_mpi_ec_set_point ("q", point, edc->ctx));
q_y = gcry_mpi_ec_get_mpi ("q@eddsa", edc->ctx, 0);
GNUNET_assert (q_y);
GNUNET_CRYPTO_mpi_print_unsigned (bin->q_y,
sizeof (bin->q_y),
q_y);
gcry_mpi_release (q_y);
}
/* This is the same as basic_ec_math but uses more advanced
features. */
static void
basic_ec_math_simplified (void)
{
gpg_error_t err;
gcry_ctx_t ctx;
gcry_mpi_point_t G, Q;
gcry_mpi_t d;
gcry_mpi_t x, y, z;
gcry_sexp_t sexp;
wherestr = "basic_ec_math_simplified";
show ("checking basic math functions for EC (variant)\n");
d = hex2mpi ("D4EF27E32F8AD8E2A1C6DDEBB1D235A69E3CEF9BCE90273D");
Q = gcry_mpi_point_new (0);
err = gcry_mpi_ec_new (&ctx, NULL, "NIST P-192");
if (err)
die ("gcry_mpi_ec_new failed: %s\n", gpg_strerror (err));
G = gcry_mpi_ec_get_point ("g", ctx, 1);
if (!G)
die ("gcry_mpi_ec_get_point(G) failed\n");
gcry_mpi_ec_mul (Q, d, G, ctx);
x = gcry_mpi_new (0);
y = gcry_mpi_new (0);
z = gcry_mpi_new (0);
gcry_mpi_point_get (x, y, z, Q);
if (cmp_mpihex (x, "222D9EC717C89D047E0898C9185B033CD11C0A981EE6DC66")
|| cmp_mpihex (y, "605DE0A82D70D3E0F84A127D0739ED33D657DF0D054BFDE8")
|| cmp_mpihex (z, "00B06B519071BC536999AC8F2D3934B3C1FC9EACCD0A31F88F"))
fail ("computed public key does not match\n");
if (debug)
{
print_mpi ("Q.x", x);
print_mpi ("Q.y", y);
print_mpi ("Q.z", z);
}
if (gcry_mpi_ec_get_affine (x, y, Q, ctx))
fail ("failed to get affine coordinates\n");
if (cmp_mpihex (x, "008532093BA023F4D55C0424FA3AF9367E05F309DC34CDC3FE")
|| cmp_mpihex (y, "00C13CA9E617C6C8487BFF6A726E3C4F277913D97117939966"))
fail ("computed affine coordinates of public key do not match\n");
if (debug)
{
print_mpi ("q.x", x);
print_mpi ("q.y", y);
}
gcry_mpi_release (z);
gcry_mpi_release (y);
gcry_mpi_release (x);
/* Let us also check wheer we can update the context. */
err = gcry_mpi_ec_set_point ("g", G, ctx);
if (err)
die ("gcry_mpi_ec_set_point(G) failed\n");
err = gcry_mpi_ec_set_mpi ("d", d, ctx);
if (err)
die ("gcry_mpi_ec_set_mpi(d) failed\n");
/* FIXME: Below we need to check that the returned S-expression is
as requested. For now we use manual inspection using --debug. */
/* Does get_sexp return the private key? */
err = gcry_pubkey_get_sexp (&sexp, 0, ctx);
if (err)
fail ("gcry_pubkey_get_sexp(0) failed: %s\n", gpg_strerror (err));
else if (verbose)
print_sexp ("Result of gcry_pubkey_get_sexp (0):\n", sexp);
gcry_sexp_release (sexp);
/* Does get_sexp return the public key if requested? */
err = gcry_pubkey_get_sexp (&sexp, GCRY_PK_GET_PUBKEY, ctx);
if (err)
fail ("gcry_pubkey_get_sexp(GET_PUBKEY) failed: %s\n", gpg_strerror (err));
else if (verbose)
print_sexp ("Result of gcry_pubkey_get_sexp (GET_PUBKEY):\n", sexp);
gcry_sexp_release (sexp);
/* Does get_sexp return the public key if after d has been deleted? */
err = gcry_mpi_ec_set_mpi ("d", NULL, ctx);
if (err)
die ("gcry_mpi_ec_set_mpi(d=NULL) failed\n");
err = gcry_pubkey_get_sexp (&sexp, 0, ctx);
if (err)
fail ("gcry_pubkey_get_sexp(0 w/o d) failed: %s\n", gpg_strerror (err));
else if (verbose)
print_sexp ("Result of gcry_pubkey_get_sexp (0 w/o d):\n", sexp);
gcry_sexp_release (sexp);
/* Does get_sexp return an error after d has been deleted? */
err = gcry_pubkey_get_sexp (&sexp, GCRY_PK_GET_SECKEY, ctx);
if (gpg_err_code (err) != GPG_ERR_NO_SECKEY)
fail ("gcry_pubkey_get_sexp(GET_SECKEY) returned wrong error: %s\n",
gpg_strerror (err));
gcry_sexp_release (sexp);
/* Does get_sexp return an error after d and Q have been deleted? */
err = gcry_mpi_ec_set_point ("q", NULL, ctx);
if (err)
die ("gcry_mpi_ec_set_point(q=NULL) failed\n");
err = gcry_pubkey_get_sexp (&sexp, 0, ctx);
if (gpg_err_code (err) != GPG_ERR_BAD_CRYPT_CTX)
fail ("gcry_pubkey_get_sexp(0 w/o Q,d) returned wrong error: %s\n",
gpg_strerror (err));
gcry_sexp_release (sexp);
gcry_mpi_point_release (Q);
gcry_mpi_release (d);
gcry_mpi_point_release (G);
gcry_ctx_release (ctx);
}
