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);
}
void gotr_gka_init()
{
gcry_error_t rc = 0;
rc = gcry_mpi_ec_new(&edctx, NULL, CURVE);
gotr_assert_gpgerr(rc);
}
/**
* Do pre-calculation for ECC discrete logarithm for small factors.
*
* @param max maximum value the factor can be
* @param mem memory to use (should be smaller than @a max), must not be zero.
* @return @a max if dlog failed, otherwise the factor
*/
struct GNUNET_CRYPTO_EccDlogContext *
GNUNET_CRYPTO_ecc_dlog_prepare (unsigned int max,
unsigned int mem)
{
struct GNUNET_CRYPTO_EccDlogContext *edc;
unsigned int K = ((max + (mem-1)) / mem);
gcry_mpi_point_t g;
struct GNUNET_PeerIdentity key;
gcry_mpi_point_t gKi;
gcry_mpi_t fact;
gcry_mpi_t n;
unsigned int i;
GNUNET_assert (max < INT32_MAX);
edc = GNUNET_new (struct GNUNET_CRYPTO_EccDlogContext);
edc->max = max;
edc->mem = mem;
edc->map = GNUNET_CONTAINER_multipeermap_create (mem * 2,
GNUNET_NO);
GNUNET_assert (0 == gcry_mpi_ec_new (&edc->ctx,
NULL,
CURVE));
g = gcry_mpi_ec_get_point ("g", edc->ctx, 0);
GNUNET_assert (NULL != g);
fact = gcry_mpi_new (0);
gKi = gcry_mpi_point_new (0);
for (i=0;i<=mem;i++)
{
gcry_mpi_set_ui (fact, i * K);
gcry_mpi_ec_mul (gKi, fact, g, edc->ctx);
extract_pk (gKi, edc->ctx, &key);
GNUNET_assert (GNUNET_OK ==
GNUNET_CONTAINER_multipeermap_put (edc->map,
&key,
(void*) (long) i + max,
GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
}
/* negative values */
n = gcry_mpi_ec_get_mpi ("n", edc->ctx, 1);
for (i=1;i<mem;i++)
{
gcry_mpi_set_ui (fact, i * K);
gcry_mpi_sub (fact, n, fact);
gcry_mpi_ec_mul (gKi, fact, g, edc->ctx);
extract_pk (gKi, edc->ctx, &key);
GNUNET_assert (GNUNET_OK ==
GNUNET_CONTAINER_multipeermap_put (edc->map,
&key,
(void*) (long) max - i,
GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
}
gcry_mpi_release (fact);
gcry_mpi_release (n);
gcry_mpi_point_release (gKi);
gcry_mpi_point_release (g);
return edc;
}
/**
* Do some DLOG operations for testing.
*
* @param edc context for ECC operations
* @param do_dlog #GNUNET_YES if we want to actually do the bencharked operation
*/
static void
test_dlog (struct GNUNET_CRYPTO_EccDlogContext *edc,
int do_dlog)
{
gcry_mpi_t fact;
gcry_mpi_t n;
gcry_ctx_t ctx;
gcry_mpi_point_t q;
gcry_mpi_point_t g;
unsigned int i;
int x;
int iret;
GNUNET_assert (0 == gcry_mpi_ec_new (&ctx, NULL, CURVE));
g = gcry_mpi_ec_get_point ("g", ctx, 0);
GNUNET_assert (NULL != g);
n = gcry_mpi_ec_get_mpi ("n", ctx, 0);
q = gcry_mpi_point_new (0);
fact = gcry_mpi_new (0);
for (i=0;i<TEST_ITER;i++)
{
fprintf (stderr, ".");
x = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
MAX_FACT);
if (0 == GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
2))
{
gcry_mpi_set_ui (fact, x);
gcry_mpi_sub (fact, n, fact);
x = - x;
}
else
{
gcry_mpi_set_ui (fact, x);
}
gcry_mpi_ec_mul (q, fact, g, ctx);
if ( (GNUNET_YES == do_dlog) &&
(x !=
(iret = GNUNET_CRYPTO_ecc_dlog (edc,
q))) )
{
fprintf (stderr,
"DLOG failed for value %d (%d)\n",
x,
iret);
GNUNET_assert (0);
}
}
gcry_mpi_release (fact);
gcry_mpi_release (n);
gcry_mpi_point_release (g);
gcry_mpi_point_release (q);
gcry_ctx_release (ctx);
fprintf (stderr, "\n");
}
static int
x25519_mpi(unsigned char *q, const unsigned char *n, gcry_mpi_t mpi_p)
{
unsigned char priv_be[32];
unsigned char result_be[32];
size_t result_len = 0;
gcry_mpi_t mpi = NULL;
gcry_ctx_t ctx = NULL;
gcry_mpi_point_t P = NULL;
gcry_mpi_point_t Q = NULL;
int r = -1;
/* Default to infinity (all zeroes). */
memset(q, 0, 32);
/* Keys are in little-endian, but gcry_mpi_scan expects big endian. Convert
* keys and ensure that the result is a valid Curve25519 secret scalar. */
copy_and_reverse(priv_be, n, 32);
priv_be[0] &= 127;
priv_be[0] |= 64;
priv_be[31] &= 248;
gcry_mpi_scan(&mpi, GCRYMPI_FMT_USG, priv_be, 32, NULL);
if (gcry_mpi_ec_new(&ctx, NULL, "Curve25519")) {
/* Should not happen, possibly out-of-memory. */
goto leave;
}
/* Compute Q = nP */
Q = gcry_mpi_point_new(0);
P = gcry_mpi_point_set(NULL, mpi_p, NULL, GCRYMPI_CONST_ONE);
gcry_mpi_ec_mul(Q, mpi, P, ctx);
/* Note: mpi is reused to store the result. */
if (gcry_mpi_ec_get_affine(mpi, NULL, Q, ctx)) {
/* Infinity. */
goto leave;
}
if (gcry_mpi_print(GCRYMPI_FMT_USG, result_be, 32, &result_len, mpi)) {
/* Should not happen, possibly out-of-memory. */
goto leave;
}
copy_and_reverse(q, result_be, result_len);
r = 0;
leave:
gcry_mpi_point_release(P);
gcry_mpi_point_release(Q);
gcry_ctx_release(ctx);
gcry_mpi_release(mpi);
/* XXX erase priv_be and result_be */
return r;
}
/* Wrapper to emulate the libgcrypt internal EC context allocation
function. */
static gpg_error_t
ec_p_new (gcry_ctx_t *r_ctx, gcry_mpi_t p, gcry_mpi_t a)
{
gpg_error_t err;
gcry_sexp_t sexp;
if (p && a)
err = gcry_sexp_build (&sexp, NULL, "(ecdsa (p %m)(a %m))", p, a);
else if (p)
err = gcry_sexp_build (&sexp, NULL, "(ecdsa (p %m))", p);
else if (a)
err = gcry_sexp_build (&sexp, NULL, "(ecdsa (a %m))", a);
else
err = gcry_sexp_build (&sexp, NULL, "(ecdsa)");
if (err)
return err;
err = gcry_mpi_ec_new (r_ctx, sexp, NULL);
gcry_sexp_release (sexp);
return err;
}
gcry_mpi_point_t deserialize_point(const struct gotr_point* data, const int len)
{
gcry_sexp_t s;
gcry_ctx_t ctx;
gcry_mpi_point_t ret;
gcry_error_t rc;
rc = gcry_sexp_build(&s, NULL, "(public-key(ecc(curve " CURVE ")(q %b)))",
len, data);
gotr_assert_gpgerr(rc);
rc = gcry_mpi_ec_new(&ctx, s, NULL);
gotr_assert_gpgerr(rc);
gcry_sexp_release(s);
ret = gcry_mpi_ec_get_point("q", ctx, 0);
gotr_assert(ret);
gcry_ctx_release(ctx);
return ret;
}
/**
* Convert binary representation of a point to computational representation.
*
* @param edc calculation context for ECC operations
* @param bin binary point representation
* @return computational representation
*/
gcry_mpi_point_t
GNUNET_CRYPTO_ecc_bin_to_point (struct GNUNET_CRYPTO_EccDlogContext *edc,
const struct GNUNET_CRYPTO_EccPoint *bin)
{
gcry_sexp_t pub_sexpr;
gcry_ctx_t ctx;
gcry_mpi_point_t q;
if (0 != gcry_sexp_build (&pub_sexpr, NULL,
"(public-key(ecc(curve " CURVE ")(q %b)))",
(int) sizeof (bin->q_y),
bin->q_y))
{
GNUNET_break (0);
return NULL;
}
GNUNET_assert (0 == gcry_mpi_ec_new (&ctx, pub_sexpr, NULL));
gcry_sexp_release (pub_sexpr);
q = gcry_mpi_ec_get_point ("q", ctx, 0);
gcry_ctx_release (ctx);
return q;
}
/* 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);
}
static void
context_param (void)
{
gpg_error_t err;
int idx;
gcry_ctx_t ctx = NULL;
gcry_mpi_t q;
gcry_sexp_t keyparam;
wherestr = "context_param";
show ("checking standard curves\n");
for (idx=0; test_curve[idx].desc; idx++)
{
gcry_ctx_release (ctx);
err = gcry_mpi_ec_new (&ctx, NULL, test_curve[idx].desc);
if (err)
{
fail ("can't create context for curve '%s': %s\n",
test_curve[idx].desc, gpg_strerror (err));
continue;
}
if (get_and_cmp_mpi ("p", test_curve[idx].p, test_curve[idx].desc, ctx))
continue;
if (get_and_cmp_mpi ("a", test_curve[idx].a, test_curve[idx].desc, ctx))
continue;
if (get_and_cmp_mpi ("b", test_curve[idx].b, test_curve[idx].desc, ctx))
continue;
if (get_and_cmp_mpi ("g.x",test_curve[idx].g_x, test_curve[idx].desc,ctx))
continue;
if (get_and_cmp_mpi ("g.y",test_curve[idx].g_y, test_curve[idx].desc,ctx))
continue;
if (get_and_cmp_mpi ("n", test_curve[idx].n, test_curve[idx].desc, ctx))
continue;
if (get_and_cmp_point ("g", test_curve[idx].g_x, test_curve[idx].g_y,
test_curve[idx].desc, ctx))
continue;
}
gcry_ctx_release (ctx);
show ("checking sample public key\n");
q = hex2mpi (sample_p256_q);
err = gcry_sexp_build (&keyparam, NULL,
"(public-key(ecdsa(curve %s)(q %m)))",
"NIST P-256", q);
if (err)
die ("gcry_sexp_build failed: %s\n", gpg_strerror (err));
gcry_mpi_release (q);
/* We can't call gcry_pk_testkey because it is only implemented for
private keys. */
/* err = gcry_pk_testkey (keyparam); */
/* if (err) */
/* fail ("gcry_pk_testkey failed for sample public key: %s\n", */
/* gpg_strerror (err)); */
err = gcry_mpi_ec_new (&ctx, keyparam, NULL);
if (err)
fail ("gcry_mpi_ec_new failed for sample public key: %s\n",
gpg_strerror (err));
else
{
gcry_sexp_t sexp;
get_and_cmp_mpi ("q", sample_p256_q, "NIST P-256", ctx);
get_and_cmp_point ("q", sample_p256_q_x, sample_p256_q_y, "NIST P-256",
ctx);
err = gcry_pubkey_get_sexp (&sexp, 0, ctx);
if (err)
fail ("gcry_pubkey_get_sexp(0) failed: %s\n", gpg_strerror (err));
else if (debug)
print_sexp ("Result of gcry_pubkey_get_sexp (0):\n", sexp);
gcry_sexp_release (sexp);
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 (debug)
print_sexp ("Result of gcry_pubkey_get_sexp (GET_PUBKEY):\n", sexp);
gcry_sexp_release (sexp);
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);
gcry_ctx_release (ctx);
}
gcry_sexp_release (keyparam);
}
/* Check the math used with Twisted Edwards curves. */
static void
twistededwards_math (void)
{
gpg_error_t err;
gcry_ctx_t ctx;
gcry_mpi_point_t G, Q;
gcry_mpi_t k;
gcry_mpi_t w, a, x, y, z, p, n, b, I;
wherestr = "twistededwards_math";
show ("checking basic Twisted Edwards math\n");
err = gcry_mpi_ec_new (&ctx, NULL, "Ed25519");
if (err)
die ("gcry_mpi_ec_new failed: %s\n", gpg_strerror (err));
k = hex2mpi
("2D3501E723239632802454EE5DDC406EFB0BDF18486A5BDE9C0390A9C2984004"
"F47252B628C953625B8DEB5DBCB8DA97AA43A1892D11FA83596F42E0D89CB1B6");
G = gcry_mpi_ec_get_point ("g", ctx, 1);
if (!G)
die ("gcry_mpi_ec_get_point(G) failed\n");
Q = gcry_mpi_point_new (0);
w = gcry_mpi_new (0);
a = gcry_mpi_new (0);
x = gcry_mpi_new (0);
y = gcry_mpi_new (0);
z = gcry_mpi_new (0);
I = gcry_mpi_new (0);
p = gcry_mpi_ec_get_mpi ("p", ctx, 1);
n = gcry_mpi_ec_get_mpi ("n", ctx, 1);
b = gcry_mpi_ec_get_mpi ("b", ctx, 1);
/* Check: 2^{p-1} mod p == 1 */
gcry_mpi_sub_ui (a, p, 1);
gcry_mpi_powm (w, GCRYMPI_CONST_TWO, a, p);
if (gcry_mpi_cmp_ui (w, 1))
fail ("failed assertion: 2^{p-1} mod p == 1\n");
/* Check: p % 4 == 1 */
gcry_mpi_mod (w, p, GCRYMPI_CONST_FOUR);
if (gcry_mpi_cmp_ui (w, 1))
fail ("failed assertion: p % 4 == 1\n");
/* Check: 2^{n-1} mod n == 1 */
gcry_mpi_sub_ui (a, n, 1);
gcry_mpi_powm (w, GCRYMPI_CONST_TWO, a, n);
if (gcry_mpi_cmp_ui (w, 1))
fail ("failed assertion: 2^{n-1} mod n == 1\n");
/* Check: b^{(p-1)/2} mod p == p-1 */
gcry_mpi_sub_ui (a, p, 1);
gcry_mpi_div (x, NULL, a, GCRYMPI_CONST_TWO, -1);
gcry_mpi_powm (w, b, x, p);
gcry_mpi_abs (w);
if (gcry_mpi_cmp (w, a))
fail ("failed assertion: b^{(p-1)/2} mod p == p-1\n");
/* I := 2^{(p-1)/4} mod p */
gcry_mpi_sub_ui (a, p, 1);
gcry_mpi_div (x, NULL, a, GCRYMPI_CONST_FOUR, -1);
gcry_mpi_powm (I, GCRYMPI_CONST_TWO, x, p);
/* Check: I^2 mod p == p-1 */
gcry_mpi_powm (w, I, GCRYMPI_CONST_TWO, p);
if (gcry_mpi_cmp (w, a))
fail ("failed assertion: I^2 mod p == p-1\n");
/* Check: G is on the curve */
if (!gcry_mpi_ec_curve_point (G, ctx))
fail ("failed assertion: G is on the curve\n");
/* Check: nG == (0,1) */
gcry_mpi_ec_mul (Q, n, G, ctx);
if (gcry_mpi_ec_get_affine (x, y, Q, ctx))
fail ("failed to get affine coordinates\n");
if (gcry_mpi_cmp_ui (x, 0) || gcry_mpi_cmp_ui (y, 1))
fail ("failed assertion: nG == (0,1)\n");
/* Now two arbitrary point operations taken from the ed25519.py
sample data. */
gcry_mpi_release (a);
a = hex2mpi
("4f71d012df3c371af3ea4dc38385ca5bb7272f90cb1b008b3ed601c76de1d496"
"e30cbf625f0a756a678d8f256d5325595cccc83466f36db18f0178eb9925edd3");
gcry_mpi_ec_mul (Q, a, G, ctx);
if (gcry_mpi_ec_get_affine (x, y, Q, ctx))
fail ("failed to get affine coordinates\n");
if (cmp_mpihex (x, ("157f7361c577aad36f67ed33e38dc7be"
"00014fecc2165ca5cee9eee19fe4d2c1"))
|| cmp_mpihex (y, ("5a69dbeb232276b38f3f5016547bb2a2"
"4025645f0b820e72b8cad4f0a909a092")))
{
fail ("sample point multiply failed:\n");
print_mpi ("r", a);
print_mpi ("Rx", x);
print_mpi ("Ry", y);
}
gcry_mpi_release (a);
a = hex2mpi
("2d3501e723239632802454ee5ddc406efb0bdf18486a5bde9c0390a9c2984004"
"f47252b628c953625b8deb5dbcb8da97aa43a1892d11fa83596f42e0d89cb1b6");
gcry_mpi_ec_mul (Q, a, G, ctx);
if (gcry_mpi_ec_get_affine (x, y, Q, ctx))
fail ("failed to get affine coordinates\n");
if (cmp_mpihex (x, ("6218e309d40065fcc338b3127f468371"
"82324bd01ce6f3cf81ab44e62959c82a"))
|| cmp_mpihex (y, ("5501492265e073d874d9e5b81e7f8784"
"8a826e80cce2869072ac60c3004356e5")))
{
fail ("sample point multiply failed:\n");
print_mpi ("r", a);
print_mpi ("Rx", x);
print_mpi ("Ry", y);
}
gcry_mpi_release (I);
gcry_mpi_release (b);
gcry_mpi_release (n);
gcry_mpi_release (p);
gcry_mpi_release (w);
gcry_mpi_release (a);
gcry_mpi_release (x);
gcry_mpi_release (y);
gcry_mpi_release (z);
gcry_mpi_point_release (Q);
gcry_mpi_point_release (G);
gcry_mpi_release (k);
gcry_ctx_release (ctx);
}
static void
context_param (void)
{
gpg_error_t err;
int idx;
gcry_ctx_t ctx = NULL;
gcry_mpi_t q, d;
gcry_sexp_t keyparam;
wherestr = "context_param";
show ("checking standard curves\n");
for (idx=0; test_curve[idx].desc; idx++)
{
gcry_ctx_release (ctx);
err = gcry_mpi_ec_new (&ctx, NULL, test_curve[idx].desc);
if (err)
{
fail ("can't create context for curve '%s': %s\n",
test_curve[idx].desc, gpg_strerror (err));
continue;
}
if (get_and_cmp_mpi ("p", test_curve[idx].p, test_curve[idx].desc, ctx))
continue;
if (get_and_cmp_mpi ("a", test_curve[idx].a, test_curve[idx].desc, ctx))
continue;
if (get_and_cmp_mpi ("b", test_curve[idx].b, test_curve[idx].desc, ctx))
continue;
if (get_and_cmp_mpi ("g.x",test_curve[idx].g_x, test_curve[idx].desc,ctx))
continue;
if (get_and_cmp_mpi ("g.y",test_curve[idx].g_y, test_curve[idx].desc,ctx))
continue;
if (get_and_cmp_mpi ("n", test_curve[idx].n, test_curve[idx].desc, ctx))
continue;
if (get_and_cmp_point ("g", test_curve[idx].g_x, test_curve[idx].g_y,
test_curve[idx].desc, ctx))
continue;
if (get_and_cmp_mpi ("h", test_curve[idx].h, test_curve[idx].desc, ctx))
continue;
}
show ("checking sample public key (nistp256)\n");
q = hex2mpi (sample_p256_q);
err = gcry_sexp_build (&keyparam, NULL,
"(public-key(ecc(curve %s)(q %m)))",
"NIST P-256", q);
if (err)
die ("gcry_sexp_build failed: %s\n", gpg_strerror (err));
gcry_mpi_release (q);
/* We can't call gcry_pk_testkey because it is only implemented for
private keys. */
/* err = gcry_pk_testkey (keyparam); */
/* if (err) */
/* fail ("gcry_pk_testkey failed for sample public key: %s\n", */
/* gpg_strerror (err)); */
gcry_ctx_release (ctx);
err = gcry_mpi_ec_new (&ctx, keyparam, NULL);
if (err)
fail ("gcry_mpi_ec_new failed for sample public key (nistp256): %s\n",
gpg_strerror (err));
else
{
gcry_sexp_t sexp;
get_and_cmp_mpi ("q", sample_p256_q, "nistp256", ctx);
get_and_cmp_point ("q", sample_p256_q_x, sample_p256_q_y, "nistp256",
ctx);
/* Delete Q. */
err = gcry_mpi_ec_set_mpi ("q", NULL, ctx);
if (err)
fail ("clearing Q for nistp256 failed: %s\n", gpg_strerror (err));
if (gcry_mpi_ec_get_mpi ("q", ctx, 0))
fail ("clearing Q for nistp256 did not work\n");
/* Set Q again. */
q = hex2mpi (sample_p256_q);
err = gcry_mpi_ec_set_mpi ("q", q, ctx);
if (err)
fail ("setting Q for nistp256 failed: %s\n", gpg_strerror (err));
get_and_cmp_mpi ("q", sample_p256_q, "nistp256(2)", ctx);
gcry_mpi_release (q);
/* Get as s-expression. */
err = gcry_pubkey_get_sexp (&sexp, 0, ctx);
if (err)
fail ("gcry_pubkey_get_sexp(0) failed: %s\n", gpg_strerror (err));
else if (debug)
print_sexp ("Result of gcry_pubkey_get_sexp (0):\n", sexp);
gcry_sexp_release (sexp);
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 (debug)
print_sexp ("Result of gcry_pubkey_get_sexp (GET_PUBKEY):\n", sexp);
gcry_sexp_release (sexp);
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);
}
show ("checking sample public key (Ed25519)\n");
q = hex2mpi (sample_ed25519_q);
gcry_sexp_release (keyparam);
err = gcry_sexp_build (&keyparam, NULL,
"(public-key(ecc(curve %s)(flags eddsa)(q %m)))",
"Ed25519", q);
if (err)
die ("gcry_sexp_build failed: %s\n", gpg_strerror (err));
gcry_mpi_release (q);
/* We can't call gcry_pk_testkey because it is only implemented for
private keys. */
/* err = gcry_pk_testkey (keyparam); */
/* if (err) */
/* fail ("gcry_pk_testkey failed for sample public key: %s\n", */
/* gpg_strerror (err)); */
gcry_ctx_release (ctx);
err = gcry_mpi_ec_new (&ctx, keyparam, NULL);
if (err)
fail ("gcry_mpi_ec_new failed for sample public key: %s\n",
gpg_strerror (err));
else
{
gcry_sexp_t sexp;
get_and_cmp_mpi ("q", sample_ed25519_q, "Ed25519", ctx);
get_and_cmp_point ("q", sample_ed25519_q_x, sample_ed25519_q_y,
"Ed25519", ctx);
get_and_cmp_mpi ("q@eddsa", sample_ed25519_q_eddsa, "Ed25519", ctx);
/* Set d to see whether Q is correctly re-computed. */
d = hex2mpi (sample_ed25519_d);
err = gcry_mpi_ec_set_mpi ("d", d, ctx);
if (err)
fail ("setting d for Ed25519 failed: %s\n", gpg_strerror (err));
gcry_mpi_release (d);
get_and_cmp_mpi ("q", sample_ed25519_q, "Ed25519(recompute Q)", ctx);
/* Delete Q by setting d and then clearing d. The clearing is
required so that we can check whether Q has been cleared and
because further tests only expect a public key. */
d = hex2mpi (sample_ed25519_d);
err = gcry_mpi_ec_set_mpi ("d", d, ctx);
if (err)
fail ("setting d for Ed25519 failed: %s\n", gpg_strerror (err));
gcry_mpi_release (d);
err = gcry_mpi_ec_set_mpi ("d", NULL, ctx);
if (err)
fail ("setting d for Ed25519 failed(2): %s\n", gpg_strerror (err));
if (gcry_mpi_ec_get_mpi ("q", ctx, 0))
fail ("setting d for Ed25519 did not reset Q\n");
/* Set Q again. We need to use an opaque MPI here because
sample_ed25519_q is in uncompressed format which can only be
auto-detected if passed opaque. */
q = hex2mpiopa (sample_ed25519_q);
err = gcry_mpi_ec_set_mpi ("q", q, ctx);
if (err)
fail ("setting Q for Ed25519 failed: %s\n", gpg_strerror (err));
gcry_mpi_release (q);
get_and_cmp_mpi ("q", sample_ed25519_q, "Ed25519(2)", ctx);
/* Get as s-expression. */
err = gcry_pubkey_get_sexp (&sexp, 0, ctx);
if (err)
fail ("gcry_pubkey_get_sexp(0) failed: %s\n", gpg_strerror (err));
else if (debug)
print_sexp ("Result of gcry_pubkey_get_sexp (0):\n", sexp);
gcry_sexp_release (sexp);
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 (debug)
print_sexp ("Result of gcry_pubkey_get_sexp (GET_PUBKEY):\n", sexp);
gcry_sexp_release (sexp);
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);
}
gcry_ctx_release (ctx);
gcry_sexp_release (keyparam);
}
/*
* Test iterative X25519 computation through lower layer MPI routines.
*
* Input: K (as hex string), ITER, R (as hex string)
*
* where R is expected result of iterating X25519 by ITER times.
*
*/
static void
test_it (int testno, const char *k_str, int iter, const char *result_str)
{
gcry_ctx_t ctx;
gpg_error_t err;
void *buffer = NULL;
size_t buflen;
gcry_mpi_t mpi_k = NULL;
gcry_mpi_t mpi_x = NULL;
gcry_mpi_point_t P = NULL;
gcry_mpi_point_t Q;
int i;
gcry_mpi_t mpi_kk = NULL;
if (verbose > 1)
info ("Running test %d: iteration=%d\n", testno, iter);
gcry_mpi_ec_new (&ctx, NULL, "Curve25519");
Q = gcry_mpi_point_new (0);
if (!(buffer = hex2buffer (k_str, &buflen)) || buflen != 32)
{
fail ("error scanning MPI for test %d, %s: %s",
testno, "k", "invalid hex string");
goto leave;
}
reverse_buffer (buffer, buflen);
if ((err = gcry_mpi_scan (&mpi_x, GCRYMPI_FMT_USG, buffer, buflen, NULL)))
{
fail ("error scanning MPI for test %d, %s: %s",
testno, "x", gpg_strerror (err));
goto leave;
}
xfree (buffer);
buffer = NULL;
P = gcry_mpi_point_set (NULL, mpi_x, NULL, GCRYMPI_CONST_ONE);
mpi_k = gcry_mpi_copy (mpi_x);
if (debug)
print_mpi ("k", mpi_k);
for (i = 0; i < iter; i++)
{
/*
* Another variant of decodeScalar25519 thing.
*/
mpi_kk = gcry_mpi_set (mpi_kk, mpi_k);
gcry_mpi_set_bit (mpi_kk, 254);
gcry_mpi_clear_bit (mpi_kk, 255);
gcry_mpi_clear_bit (mpi_kk, 0);
gcry_mpi_clear_bit (mpi_kk, 1);
gcry_mpi_clear_bit (mpi_kk, 2);
gcry_mpi_ec_mul (Q, mpi_kk, P, ctx);
P = gcry_mpi_point_set (P, mpi_k, NULL, GCRYMPI_CONST_ONE);
gcry_mpi_ec_get_affine (mpi_k, NULL, Q, ctx);
if (debug)
print_mpi ("k", mpi_k);
}
{
unsigned char res[32];
char *r, *r0;
gcry_mpi_print (GCRYMPI_FMT_USG, res, 32, NULL, mpi_k);
reverse_buffer (res, 32);
r0 = r = xmalloc (65);
if (!r0)
{
fail ("memory allocation for test %d", testno);
goto leave;
}
for (i=0; i < 32; i++, r += 2)
snprintf (r, 3, "%02x", res[i]);
if (strcmp (result_str, r0))
{
fail ("curv25519 failed for test %d: %s",
testno, "wrong value returned");
info (" expected: '%s'", result_str);
info (" got: '%s'", r0);
}
xfree (r0);
}
leave:
gcry_mpi_release (mpi_kk);
gcry_mpi_release (mpi_k);
gcry_mpi_point_release (P);
gcry_mpi_release (mpi_x);
xfree (buffer);
gcry_mpi_point_release (Q);
gcry_ctx_release (ctx);
}