#include <gcrypt.h>
#include "gnunet_util_lib.h"
-#define EXTRA_CHECKS ALLOW_EXTRA_CHECKS
+#define EXTRA_CHECKS 0
/**
* Name of the curve we are using. Note that we have hard-coded
* 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__)
}
-/**
- * If target != size, move @a target bytes to the end of the size-sized
- * buffer and zero out the first @a target - @a size bytes.
- *
- * @param buf original buffer
- * @param size number of bytes in @a buf
- * @param target target size of the buffer
- */
-static void
-adjust (unsigned char *buf,
- size_t size,
- size_t target)
-{
- if (size < target)
- {
- memmove (&buf[target - size], buf, size);
- memset (buf, 0, target - size);
- }
-}
-
-
-/**
- * Output the given MPI value to the given buffer.
- *
- * @param buf where to output to
- * @param size number of bytes in @a buf
- * @param val value to write to @a buf
- */
-static void
-mpi_print (unsigned char *buf,
- size_t size,
- gcry_mpi_t val)
-{
- size_t rsize;
-
- rsize = size;
- GNUNET_assert (0 ==
- gcry_mpi_print (GCRYMPI_FMT_USG, buf, rsize, &rsize,
- val));
- adjust (buf, rsize, size);
-}
-
-
-/**
- * Convert data buffer into MPI value.
- *
- * @param result where to store MPI value (allocated)
- * @param data raw data (GCRYMPI_FMT_USG)
- * @param size number of bytes in data
- */
-static void
-mpi_scan (gcry_mpi_t *result,
- const unsigned char *data,
- size_t size)
-{
- int rc;
-
- if (0 != (rc = gcry_mpi_scan (result,
- GCRYMPI_FMT_USG,
- data, size, &size)))
- {
- LOG_GCRY (GNUNET_ERROR_TYPE_ERROR, "gcry_mpi_scan", rc);
- GNUNET_assert (0);
- }
-}
-
-
/**
* Convert the given private key from the network format to the
* S-expression that can be used by libgcrypt.
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);
+ GNUNET_CRYPTO_mpi_print_unsigned (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);
+ GNUNET_CRYPTO_mpi_print_unsigned (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);
+ GNUNET_CRYPTO_mpi_print_unsigned (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;
}
gcry_sexp_release (priv_sexp);
priv = GNUNET_new (struct GNUNET_CRYPTO_EcdhePrivateKey);
- mpi_print (priv->d, sizeof (priv->d), d);
+ GNUNET_CRYPTO_mpi_print_unsigned (priv->d, sizeof (priv->d), d);
gcry_mpi_release (d);
return priv;
}
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;
}
gcry_sexp_release (priv_sexp);
priv = GNUNET_new (struct GNUNET_CRYPTO_EcdsaPrivateKey);
- mpi_print (priv->d, sizeof (priv->d), d);
+ GNUNET_CRYPTO_mpi_print_unsigned (priv->d, sizeof (priv->d), d);
gcry_mpi_release (d);
return priv;
}
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;
}
gcry_sexp_release (priv_sexp);
priv = GNUNET_new (struct GNUNET_CRYPTO_EddsaPrivateKey);
- mpi_print (priv->d, sizeof (priv->d), d);
+ GNUNET_CRYPTO_mpi_print_unsigned (priv->d, sizeof (priv->d), d);
gcry_mpi_release (d);
return priv;
}
if (once)
return &anonymous;
- mpi_print (anonymous.d,
+ GNUNET_CRYPTO_mpi_print_unsigned (anonymous.d,
sizeof (anonymous.d),
GCRYMPI_CONST_ONE);
once = 1;
}
+/**
+ * Compare two Peer Identities.
+ *
+ * @param first first peer identity
+ * @param second second peer identity
+ * @return bigger than 0 if first > second,
+ * 0 if they are the same
+ * smaller than 0 if second > first
+ */
+int
+GNUNET_CRYPTO_cmp_peer_identity (const struct GNUNET_PeerIdentity *first,
+ const struct GNUNET_PeerIdentity *second)
+{
+ return memcmp (first, second, sizeof (struct GNUNET_PeerIdentity));
+}
+
+
/**
* Convert the data specified in the given purpose argument to an
* S-expression suitable for signature operations.
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;
return GNUNET_SYSERR;
}
gcry_sexp_release (sig_sexp);
- mpi_print (sig->r, sizeof (sig->r), rs[0]);
- mpi_print (sig->s, sizeof (sig->s), rs[1]);
+ GNUNET_CRYPTO_mpi_print_unsigned (sig->r, sizeof (sig->r), rs[0]);
+ GNUNET_CRYPTO_mpi_print_unsigned (sig->s, sizeof (sig->s), rs[1]);
gcry_mpi_release (rs[0]);
gcry_mpi_release (rs[1]);
return GNUNET_OK;
return GNUNET_SYSERR;
}
gcry_sexp_release (sig_sexp);
- mpi_print (sig->r, sizeof (sig->r), rs[0]);
- mpi_print (sig->s, sizeof (sig->s), rs[1]);
+ GNUNET_CRYPTO_mpi_print_unsigned (sig->r, sizeof (sig->r), rs[0]);
+ GNUNET_CRYPTO_mpi_print_unsigned (sig->s, sizeof (sig->s), rs[1]);
gcry_mpi_release (rs[0]);
gcry_mpi_release (rs[1]);
return GNUNET_OK;
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);
q = gcry_mpi_ec_get_point ("q", ctx, 0);
/* second, extract the d value from our private key */
- mpi_scan (&d, priv->d, sizeof (priv->d));
+ GNUNET_CRYPTO_mpi_scan_unsigned (&d, priv->d, sizeof (priv->d));
/* then call the 'multiply' function, to compute the product */
result = gcry_mpi_point_new (0);
/* 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 'GNUNET_CRYPTO_mpi_print_unsigned'
+ 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;
}
label, strlen (label),
context, strlen (context),
NULL, 0);
- mpi_scan (&h, (unsigned char *) &hc, sizeof (hc));
+ GNUNET_CRYPTO_mpi_scan_unsigned (&h, (unsigned char *) &hc, sizeof (hc));
return h;
}
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));
+ GNUNET_CRYPTO_mpi_scan_unsigned (&x, priv->d, sizeof (priv->d));
d = gcry_mpi_new (256);
gcry_mpi_mulm (d, h, x, n);
gcry_mpi_release (h);
gcry_mpi_release (n);
gcry_ctx_release (ctx);
ret = GNUNET_new (struct GNUNET_CRYPTO_EcdsaPrivateKey);
- mpi_print (ret->d, sizeof (ret->d), d);
+ GNUNET_CRYPTO_mpi_print_unsigned (ret->d, sizeof (ret->d), d);
gcry_mpi_release (d);
return ret;
}
+/**
+ * Computes a new PeerIdentity using the Chord formula.
+ * new_peer_identity = ((my_identity + pow(2,i)) mod (pow(2,m)
+ * where m, size of struct GNUNET_PeerIdentity in bits.
+ * i, 0 <= i <= m
+ * @param my_identity original PeerIdentity
+ * @param value of i.
+ * @return finger_identity
+ */
+struct GNUNET_PeerIdentity *
+GNUNET_CRYPTO_compute_finger(struct GNUNET_PeerIdentity *my_identity, unsigned int index)
+{
+ gcry_mpi_t my_identity_mpi;
+ gcry_mpi_t finger_identity_mpi;
+ gcry_mpi_t add;
+ gcry_mpi_t mod;
+ gcry_error_t rc;
+ struct GNUNET_PeerIdentity *finger_identity;
+ size_t read = 0;
+ size_t write = 0;
+
+ finger_identity = GNUNET_malloc(sizeof(struct GNUNET_PeerIdentity));
+
+ /* Initialize my_identity_mpi. */
+ my_identity_mpi = gcry_mpi_new(8*sizeof(struct GNUNET_PeerIdentity));
+
+ /* Copy my_identity into my_id */
+ if(0 != (rc = gcry_mpi_scan(&my_identity_mpi, GCRYMPI_FMT_USG, my_identity->public_key.q_y,
+ sizeof(struct GNUNET_PeerIdentity), &read)))
+ {
+ LOG_GCRY (GNUNET_ERROR_TYPE_DEBUG, "gcry_mpi_scan", rc);
+ GNUNET_free(finger_identity);
+ return NULL;
+ }
+
+ /* Initialize finger_identity_mpi */
+ finger_identity_mpi = gcry_mpi_new(8*sizeof(struct GNUNET_PeerIdentity));
+
+ /* Initialize add */
+ add = gcry_mpi_new(8*sizeof(struct GNUNET_PeerIdentity));
+
+ /* Set the index bit in add.*/
+ gcry_mpi_set_bit(add,index);
+
+ /* Initialize mod */
+ mod = gcry_mpi_new(8*sizeof(struct GNUNET_PeerIdentity) + 1);
+ gcry_mpi_set_bit(mod,257);
+ gcry_mpi_sub_ui(mod,mod,(unsigned long)1);
+
+
+ /* finger_identity_mpi = (my_identity_mpi + add) % mod */
+ gcry_mpi_addm(finger_identity_mpi,my_identity_mpi,add,mod);
+
+
+ /* Copy finger_identity_mpi to finger_identity */
+ if(0 != (rc = gcry_mpi_print(GCRYMPI_FMT_USG,finger_identity->public_key.q_y,
+ 32,&write,finger_identity_mpi)))
+ {
+ LOG_GCRY (GNUNET_ERROR_TYPE_DEBUG, "gcry_mpi_print", rc);
+ GNUNET_free(finger_identity);
+ return NULL;
+ }
+
+ return finger_identity;
+}
+
+
/**
* Derive a public key from a given public key and a label.
* Essentially calculates a public key 'V = H(l,P) * P'.
*
* @param pub original public key
- * @param label label to use for key deriviation
+ * @param label label to use for key derivation
* @param context additional context to use for HKDF of 'h';
* typically the name of the subsystem/application
* @param result where to write the derived public key
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 */
+ /* calculate h_mod_n = h % n */
h = derive_h (pub, label, context);
n = gcry_mpi_ec_get_mpi ("n", ctx, 1);
h_mod_n = gcry_mpi_new (256);
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);
+ GNUNET_CRYPTO_mpi_print_unsigned (result->q_y, sizeof result->q_y, q_y);
+ gcry_mpi_release (q_y);
gcry_ctx_release (ctx);
}
projects / oweals / gnunet.git / blobdiff