* structs that use 256 bits, so using a bigger curve will require
* changes that break stuff badly. The name of the curve given here
* must be agreed by all peers and be supported by libgcrypt.
- *
- * NOTE: this will change to Curve25519 before GNUnet 0.10.0.
*/
-#define CURVE "NIST P-256"
+#define CURVE "Ed25519"
#define LOG(kind,...) GNUNET_log_from (kind, "util", __VA_ARGS__)
{
size_t rsize;
- rsize = size;
- GNUNET_assert (0 ==
- gcry_mpi_print (GCRYMPI_FMT_USG, buf, rsize, &rsize,
- val));
- adjust (buf, rsize, size);
+ if (gcry_mpi_get_flag (val, GCRYMPI_FLAG_OPAQUE))
+ {
+ /* Store opaque MPIs left aligned into the buffer. */
+ unsigned int nbits;
+ const void *p;
+
+ p = gcry_mpi_get_opaque (val, &nbits);
+ GNUNET_assert (p);
+ rsize = (nbits+7)/8;
+ if (rsize > size)
+ rsize = size;
+ memcpy (buf, p, rsize);
+ if (rsize < size)
+ memset (buf+rsize, 0, size - rsize);
+ }
+ else
+ {
+ /* Store regular MPIs as unsigned integers right aligned into
+ the buffer. */
+ rsize = size;
+ GNUNET_assert (0 ==
+ gcry_mpi_print (GCRYMPI_FMT_USG, buf, rsize, &rsize,
+ val));
+ adjust (buf, rsize, size);
+ }
}
decode_private_ecdsa_key (const struct GNUNET_CRYPTO_EcdsaPrivateKey *priv)
{
gcry_sexp_t result;
- gcry_mpi_t d;
int rc;
- mpi_scan (&d,
- priv->d,
- sizeof (priv->d));
rc = gcry_sexp_build (&result, NULL,
- "(private-key(ecdsa(curve \"" CURVE "\")(d %m)))",
- d);
- gcry_mpi_release (d);
+ "(private-key(ecc(curve \"" CURVE "\")"
+ "(d %b)))",
+ (int)sizeof (priv->d), priv->d);
if (0 != rc)
{
LOG_GCRY (GNUNET_ERROR_TYPE_ERROR, "gcry_sexp_build", rc);
decode_private_eddsa_key (const struct GNUNET_CRYPTO_EddsaPrivateKey *priv)
{
gcry_sexp_t result;
- gcry_mpi_t d;
int rc;
- mpi_scan (&d,
- priv->d,
- sizeof (priv->d));
rc = gcry_sexp_build (&result, NULL,
- "(private-key(ecdsa(curve \"" CURVE "\")(d %m)))", // FIXME: eddsa soon!
- d);
- gcry_mpi_release (d);
+ "(private-key(ecc(curve \"" CURVE "\")"
+ "(flags eddsa)(d %b)))",
+ (int)sizeof (priv->d), priv->d);
if (0 != rc)
{
LOG_GCRY (GNUNET_ERROR_TYPE_ERROR, "gcry_sexp_build", rc);
decode_private_ecdhe_key (const struct GNUNET_CRYPTO_EcdhePrivateKey *priv)
{
gcry_sexp_t result;
- gcry_mpi_t d;
int rc;
- mpi_scan (&d,
- priv->d,
- sizeof (priv->d));
rc = gcry_sexp_build (&result, NULL,
- "(private-key(ecdsa(curve \"" CURVE "\")(d %m)))", // FIXME: ecdh here?
- d);
- gcry_mpi_release (d);
+ "(private-key(ecc(curve \"" CURVE "\")"
+ "(d %b)))",
+ (int)sizeof (priv->d), priv->d);
if (0 != rc)
{
LOG_GCRY (GNUNET_ERROR_TYPE_ERROR, "gcry_sexp_build", rc);
}
-/**
- * Initialize public key struct from the respective point
- * on the curve.
- *
- * @param q point on curve
- * @param pub public key struct to initialize
- * @param ctx context to use for ECC operations
- */
-static void
-point_to_public_ecdsa_key (gcry_mpi_point_t q,
- gcry_ctx_t ctx,
- struct GNUNET_CRYPTO_EcdsaPublicKey *pub)
-{
- gcry_mpi_t q_x;
- gcry_mpi_t q_y;
-
- q_x = gcry_mpi_new (256);
- q_y = gcry_mpi_new (256);
- if (gcry_mpi_ec_get_affine (q_x, q_y, q, ctx))
- {
- LOG_GCRY (GNUNET_ERROR_TYPE_ERROR, "get_affine failed", 0);
- return;
- }
-
- mpi_print (pub->q_x, sizeof (pub->q_x), q_x);
- mpi_print (pub->q_y, sizeof (pub->q_y), q_y);
- gcry_mpi_release (q_x);
- gcry_mpi_release (q_y);
-}
-
-
-/**
- * Initialize public key struct from the respective point
- * on the curve.
- *
- * @param q point on curve
- * @param pub public key struct to initialize
- * @param ctx context to use for ECC operations
- */
-static void
-point_to_public_eddsa_key (gcry_mpi_point_t q,
- gcry_ctx_t ctx,
- struct GNUNET_CRYPTO_EddsaPublicKey *pub)
-{
- gcry_mpi_t q_x;
- gcry_mpi_t q_y;
-
- q_x = gcry_mpi_new (256);
- q_y = gcry_mpi_new (256);
- if (gcry_mpi_ec_get_affine (q_x, q_y, q, ctx))
- {
- LOG_GCRY (GNUNET_ERROR_TYPE_ERROR, "get_affine failed", 0);
- return;
- }
-
- mpi_print (pub->q_x, sizeof (pub->q_x), q_x);
- mpi_print (pub->q_y, sizeof (pub->q_y), q_y);
- gcry_mpi_release (q_x);
- gcry_mpi_release (q_y);
-}
-
-
-/**
- * Initialize public key struct from the respective point
- * on the curve.
- *
- * @param q point on curve
- * @param pub public key struct to initialize
- * @param ctx context to use for ECC operations
- */
-static void
-point_to_public_ecdhe_key (gcry_mpi_point_t q,
- gcry_ctx_t ctx,
- struct GNUNET_CRYPTO_EcdhePublicKey *pub)
-{
- gcry_mpi_t q_x;
- gcry_mpi_t q_y;
-
- q_x = gcry_mpi_new (256);
- q_y = gcry_mpi_new (256);
- if (gcry_mpi_ec_get_affine (q_x, q_y, q, ctx))
- {
- LOG_GCRY (GNUNET_ERROR_TYPE_ERROR, "get_affine failed", 0);
- return;
- }
-
- mpi_print (pub->q_x, sizeof (pub->q_x), q_x);
- mpi_print (pub->q_y, sizeof (pub->q_y), q_y);
- gcry_mpi_release (q_x);
- gcry_mpi_release (q_y);
-}
-
-
/**
* Extract the public key for the given private key.
*
{
gcry_sexp_t sexp;
gcry_ctx_t ctx;
- gcry_mpi_point_t q;
+ gcry_mpi_t q;
sexp = decode_private_ecdsa_key (priv);
GNUNET_assert (NULL != sexp);
GNUNET_assert (0 == gcry_mpi_ec_new (&ctx, sexp, NULL));
gcry_sexp_release (sexp);
- q = gcry_mpi_ec_get_point ("q", ctx, 0);
- point_to_public_ecdsa_key (q, ctx, pub);
+ q = gcry_mpi_ec_get_mpi ("q@eddsa", ctx, 0);
+ GNUNET_assert (q);
+ mpi_print (pub->q_y, sizeof (pub->q_y), q);
+ gcry_mpi_release (q);
gcry_ctx_release (ctx);
- gcry_mpi_point_release (q);
}
{
gcry_sexp_t sexp;
gcry_ctx_t ctx;
- gcry_mpi_point_t q;
+ gcry_mpi_t q;
sexp = decode_private_eddsa_key (priv);
GNUNET_assert (NULL != sexp);
GNUNET_assert (0 == gcry_mpi_ec_new (&ctx, sexp, NULL));
gcry_sexp_release (sexp);
- q = gcry_mpi_ec_get_point ("q", ctx, 0);
- point_to_public_eddsa_key (q, ctx, pub);
+ q = gcry_mpi_ec_get_mpi ("q@eddsa", ctx, 0);
+ GNUNET_assert (q);
+ mpi_print (pub->q_y, sizeof (pub->q_y), q);
+ gcry_mpi_release (q);
gcry_ctx_release (ctx);
- gcry_mpi_point_release (q);
}
{
gcry_sexp_t sexp;
gcry_ctx_t ctx;
- gcry_mpi_point_t q;
+ gcry_mpi_t q;
sexp = decode_private_ecdhe_key (priv);
GNUNET_assert (NULL != sexp);
GNUNET_assert (0 == gcry_mpi_ec_new (&ctx, sexp, NULL));
gcry_sexp_release (sexp);
- q = gcry_mpi_ec_get_point ("q", ctx, 0);
- point_to_public_ecdhe_key (q, ctx, pub);
+ q = gcry_mpi_ec_get_mpi ("q@eddsa", ctx, 0);
+ GNUNET_assert (q);
+ mpi_print (pub->q_y, sizeof (pub->q_y), q);
+ gcry_mpi_release (q);
gcry_ctx_release (ctx);
- gcry_mpi_point_release (q);
}
}
-/**
- * Convert the given public key from the network format to the
- * S-expression that can be used by libgcrypt.
- *
- * @param pub public key to decode
- * @return NULL on error
- */
-static gcry_sexp_t
-decode_public_ecdsa_key (const struct GNUNET_CRYPTO_EcdsaPublicKey *pub)
-{
- gcry_sexp_t pub_sexp;
- gcry_mpi_t q_x;
- gcry_mpi_t q_y;
- gcry_mpi_point_t q;
- gcry_ctx_t ctx;
-
- mpi_scan (&q_x, pub->q_x, sizeof (pub->q_x));
- mpi_scan (&q_y, pub->q_y, sizeof (pub->q_y));
- q = gcry_mpi_point_new (256);
- gcry_mpi_point_set (q, q_x, q_y, GCRYMPI_CONST_ONE);
- gcry_mpi_release (q_x);
- gcry_mpi_release (q_y);
-
- /* initialize 'ctx' with 'q' */
- GNUNET_assert (0 == gcry_mpi_ec_new (&ctx, NULL, CURVE)); // FIXME: need to say ECDSA?
- gcry_mpi_ec_set_point ("q", q, ctx);
- gcry_mpi_point_release (q);
-
- /* convert 'ctx' to 'sexp' */
- GNUNET_assert (0 == gcry_pubkey_get_sexp (&pub_sexp, GCRY_PK_GET_PUBKEY, ctx));
- gcry_ctx_release (ctx);
- return pub_sexp;
-}
-
-
-/**
- * Convert the given public key from the network format to the
- * S-expression that can be used by libgcrypt.
- *
- * @param pub public key to decode
- * @return NULL on error
- */
-static gcry_sexp_t
-decode_public_eddsa_key (const struct GNUNET_CRYPTO_EddsaPublicKey *pub)
-{
- gcry_sexp_t pub_sexp;
- gcry_mpi_t q_x;
- gcry_mpi_t q_y;
- gcry_mpi_point_t q;
- gcry_ctx_t ctx;
-
- mpi_scan (&q_x, pub->q_x, sizeof (pub->q_x));
- mpi_scan (&q_y, pub->q_y, sizeof (pub->q_y));
- q = gcry_mpi_point_new (256);
- gcry_mpi_point_set (q, q_x, q_y, GCRYMPI_CONST_ONE);
- gcry_mpi_release (q_x);
- gcry_mpi_release (q_y);
-
- /* initialize 'ctx' with 'q' */
- GNUNET_assert (0 == gcry_mpi_ec_new (&ctx, NULL, CURVE)); // FIXME: need to say EdDSA?
- gcry_mpi_ec_set_point ("q", q, ctx);
- gcry_mpi_point_release (q);
-
- /* convert 'ctx' to 'sexp' */
- GNUNET_assert (0 == gcry_pubkey_get_sexp (&pub_sexp, GCRY_PK_GET_PUBKEY, ctx));
- gcry_ctx_release (ctx);
- return pub_sexp;
-}
-
-
/**
* @ingroup crypto
* Clear memory that was used to store a private key.
int rc;
if (0 != (rc = gcry_sexp_build (&s_keyparam, NULL,
- "(genkey(ecdsa(curve \"" CURVE "\")))"))) // FIXME: ECDHE?
+ "(genkey(ecc(curve \"" CURVE "\")"
+ "(flags)))")))
{
LOG_GCRY (GNUNET_ERROR_TYPE_ERROR, "gcry_sexp_build", rc);
return NULL;
int rc;
if (0 != (rc = gcry_sexp_build (&s_keyparam, NULL,
- "(genkey(ecdsa(curve \"" CURVE "\")))")))
+ "(genkey(ecc(curve \"" CURVE "\")"
+ "(flags)))")))
{
LOG_GCRY (GNUNET_ERROR_TYPE_ERROR, "gcry_sexp_build", rc);
return NULL;
int rc;
if (0 != (rc = gcry_sexp_build (&s_keyparam, NULL,
- "(genkey(ecdsa(curve \"" CURVE "\")))"))) // FIXME: EdDSA?
+ "(genkey(ecc(curve \"" CURVE "\")"
+ "(flags eddsa)))")))
{
LOG_GCRY (GNUNET_ERROR_TYPE_ERROR, "gcry_sexp_build", rc);
return NULL;
GNUNET_CRYPTO_hash (purpose, ntohl (purpose->size), &hc);
if (0 != (rc = gcry_sexp_build (&data, NULL,
- "(data(flags rfc6979)(hash %s %b))", // FIXME: use EdDSA encoding!
+ "(data(flags eddsa)(hash-algo %s)(value %b))",
"sha512",
- sizeof (hc),
- &hc)))
+ (int)sizeof (hc), &hc)))
{
LOG_GCRY (GNUNET_ERROR_TYPE_ERROR, "gcry_sexp_build", rc);
return NULL;
if (0 != (rc = gcry_sexp_build (&data, NULL,
"(data(flags rfc6979)(hash %s %b))",
"sha512",
- sizeof (hc),
- &hc)))
+ (int)sizeof (hc), &hc)))
{
LOG_GCRY (GNUNET_ERROR_TYPE_ERROR, "gcry_sexp_build", rc);
return NULL;
gcry_sexp_t sig_sexpr;
gcry_sexp_t pub_sexpr;
int rc;
- gcry_mpi_t r;
- gcry_mpi_t s;
if (purpose != ntohl (validate->purpose))
return GNUNET_SYSERR; /* purpose mismatch */
/* build s-expression for signature */
- mpi_scan (&r, sig->r, sizeof (sig->r));
- mpi_scan (&s, sig->s, sizeof (sig->s));
if (0 != (rc = gcry_sexp_build (&sig_sexpr, NULL,
- "(sig-val(ecdsa(r %m)(s %m)))",
- r, s)))
+ "(sig-val(ecdsa(r %b)(s %b)))",
+ (int)sizeof (sig->r), sig->r,
+ (int)sizeof (sig->s), sig->s)))
{
LOG_GCRY (GNUNET_ERROR_TYPE_ERROR, "gcry_sexp_build", rc);
- gcry_mpi_release (r);
- gcry_mpi_release (s);
return GNUNET_SYSERR;
}
- gcry_mpi_release (r);
- gcry_mpi_release (s);
data = data_to_ecdsa_value (validate);
- if (! (pub_sexpr = decode_public_ecdsa_key (pub)))
+ if (0 != (rc = gcry_sexp_build (&pub_sexpr, NULL,
+ "(public-key(ecc(curve " CURVE ")(q %b)))",
+ (int)sizeof (pub->q_y), pub->q_y)))
{
gcry_sexp_release (data);
gcry_sexp_release (sig_sexpr);
gcry_sexp_t sig_sexpr;
gcry_sexp_t pub_sexpr;
int rc;
- gcry_mpi_t r;
- gcry_mpi_t s;
if (purpose != ntohl (validate->purpose))
return GNUNET_SYSERR; /* purpose mismatch */
/* build s-expression for signature */
- mpi_scan (&r, sig->r, sizeof (sig->r));
- mpi_scan (&s, sig->s, sizeof (sig->s));
if (0 != (rc = gcry_sexp_build (&sig_sexpr, NULL,
- "(sig-val(eddsa(r %m)(s %m)))",
- r, s)))
+ "(sig-val(eddsa(r %b)(s %b)))",
+ (int)sizeof (sig->r), sig->r,
+ (int)sizeof (sig->s), sig->s)))
{
LOG_GCRY (GNUNET_ERROR_TYPE_ERROR, "gcry_sexp_build", rc);
- gcry_mpi_release (r);
- gcry_mpi_release (s);
return GNUNET_SYSERR;
}
- gcry_mpi_release (r);
- gcry_mpi_release (s);
data = data_to_eddsa_value (validate);
- if (! (pub_sexpr = decode_public_eddsa_key (pub)))
+ if (0 != (rc = gcry_sexp_build (&pub_sexpr, NULL,
+ "(public-key(ecc(curve " CURVE ")(q %b)))",
+ (int)sizeof (pub->q_y), pub->q_y)))
{
gcry_sexp_release (data);
gcry_sexp_release (sig_sexpr);
}
-/**
- * Convert the given public key from the network format to the
- * S-expression that can be used by libgcrypt.
- *
- * @param pub public key to decode
- * @return NULL on error
- */
-static gcry_sexp_t
-decode_public_ecdhe_key (const struct GNUNET_CRYPTO_EcdhePublicKey *pub)
-{
- gcry_sexp_t pub_sexp;
- gcry_mpi_t q_x;
- gcry_mpi_t q_y;
- gcry_mpi_point_t q;
- gcry_ctx_t ctx;
-
- mpi_scan (&q_x, pub->q_x, sizeof (pub->q_x));
- mpi_scan (&q_y, pub->q_y, sizeof (pub->q_y));
- q = gcry_mpi_point_new (256);
- gcry_mpi_point_set (q, q_x, q_y, GCRYMPI_CONST_ONE);
- gcry_mpi_release (q_x);
- gcry_mpi_release (q_y);
-
- /* initialize 'ctx' with 'q' */
- GNUNET_assert (0 == gcry_mpi_ec_new (&ctx, NULL, CURVE));
- gcry_mpi_ec_set_point ("q", q, ctx);
- gcry_mpi_point_release (q);
-
- /* convert 'ctx' to 'sexp' */
- GNUNET_assert (0 == gcry_pubkey_get_sexp (&pub_sexp, GCRY_PK_GET_PUBKEY, ctx));
- gcry_ctx_release (ctx);
- return pub_sexp;
-}
-
-
/**
* Derive key material from a public and a private ECDHE key.
*
gcry_ctx_t ctx;
gcry_sexp_t pub_sexpr;
gcry_mpi_t result_x;
- gcry_mpi_t result_y;
unsigned char xbuf[256 / 8];
+ size_t rsize;
/* first, extract the q = dP value from the public key */
- if (! (pub_sexpr = decode_public_ecdhe_key (pub)))
+ if (0 != gcry_sexp_build (&pub_sexpr, NULL,
+ "(public-key(ecc(curve " CURVE ")(q %b)))",
+ (int)sizeof (pub->q_y), pub->q_y))
return GNUNET_SYSERR;
GNUNET_assert (0 == gcry_mpi_ec_new (&ctx, pub_sexpr, NULL));
gcry_sexp_release (pub_sexpr);
/* finally, convert point to string for hashing */
result_x = gcry_mpi_new (256);
- result_y = gcry_mpi_new (256);
- if (gcry_mpi_ec_get_affine (result_x, result_y, result, ctx))
+ if (gcry_mpi_ec_get_affine (result_x, NULL, result, ctx))
{
LOG_GCRY (GNUNET_ERROR_TYPE_ERROR, "get_affine failed", 0);
gcry_mpi_point_release (result);
gcry_mpi_point_release (result);
gcry_ctx_release (ctx);
- mpi_print (xbuf, sizeof (xbuf), result_x);
- GNUNET_CRYPTO_hash (xbuf, sizeof (xbuf), key_material);
+ rsize = sizeof (xbuf);
+ GNUNET_assert (! gcry_mpi_get_flag (result_x, GCRYMPI_FLAG_OPAQUE));
+ /* result_x can be negative here, so we do not use 'mpi_print'
+ as that does not include the sign bit; x should be a 255-bit
+ value, so with the sign it should fit snugly into the 256-bit
+ xbuf */
+ GNUNET_assert (0 ==
+ gcry_mpi_print (GCRYMPI_FMT_STD, xbuf, rsize, &rsize,
+ result_x));
+ GNUNET_CRYPTO_hash (xbuf, rsize, key_material);
gcry_mpi_release (result_x);
- gcry_mpi_release (result_y);
return GNUNET_OK;
}
gcry_ctx_t ctx;
GNUNET_assert (0 == gcry_mpi_ec_new (&ctx, NULL, CURVE));
+
n = gcry_mpi_ec_get_mpi ("n", ctx, 1);
GNUNET_CRYPTO_ecdsa_key_get_public (priv, &pub);
+
h = derive_h (&pub, label, context);
mpi_scan (&x, priv->d, sizeof (priv->d));
d = gcry_mpi_new (256);
struct GNUNET_CRYPTO_EcdsaPublicKey *result)
{
gcry_ctx_t ctx;
+ gcry_mpi_t q_y;
gcry_mpi_t h;
gcry_mpi_t n;
gcry_mpi_t h_mod_n;
- gcry_mpi_t q_x;
- gcry_mpi_t q_y;
gcry_mpi_point_t q;
gcry_mpi_point_t v;
GNUNET_assert (0 == gcry_mpi_ec_new (&ctx, NULL, CURVE));
- /* obtain point 'q' from original public key */
- mpi_scan (&q_x, pub->q_x, sizeof (pub->q_x));
- mpi_scan (&q_y, pub->q_y, sizeof (pub->q_y));
-
- q = gcry_mpi_point_new (0);
- gcry_mpi_point_set (q, q_x, q_y, GCRYMPI_CONST_ONE);
- gcry_mpi_release (q_x);
+ /* obtain point 'q' from original public key. The provided 'q' is
+ compressed thus we first store it in the context and then get it
+ back as a (decompresssed) point. */
+ q_y = gcry_mpi_set_opaque_copy (NULL, pub->q_y, 8*sizeof (pub->q_y));
+ GNUNET_assert (q_y);
+ GNUNET_assert (0 == gcry_mpi_ec_set_mpi ("q", q_y, ctx));
gcry_mpi_release (q_y);
+ q = gcry_mpi_ec_get_point ("q", ctx, 0);
+ GNUNET_assert (q);
/* calulcate h_mod_n = h % n */
h = derive_h (pub, label, context);
gcry_mpi_release (h);
gcry_mpi_release (n);
gcry_mpi_point_release (q);
+
/* convert point 'v' to public key that we return */
- point_to_public_ecdsa_key (v, ctx, result);
+ GNUNET_assert (0 == gcry_mpi_ec_set_point ("q", v, ctx));
gcry_mpi_point_release (v);
+ q_y = gcry_mpi_ec_get_mpi ("q@eddsa", ctx, 0);
+ GNUNET_assert (q_y);
+ mpi_print (result->q_y, sizeof result->q_y, q_y);
+ gcry_mpi_release (q_y);
gcry_ctx_release (ctx);
}