*/
#include "platform.h"
#include <gcrypt.h>
-#include "gnunet_common.h"
#include "gnunet_util_lib.h"
-#define EXTRA_CHECKS ALLOW_EXTRA_CHECKS
+#define EXTRA_CHECKS ALLOW_EXTRA_CHECKS
/**
* 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"
* a failure of the command 'cmd' with the message given
* by gcry_strerror(rc).
*/
-#define LOG_GCRY(level, cmd, rc) do { LOG(level, _("`%s' failed at %s:%d with error: %s\n"), cmd, __FILE__, __LINE__, gcry_strerror(rc)); } while(0);
+#define LOG_GCRY(level, cmd, rc) do { LOG(level, _("`%s' failed at %s:%d with error: %s\n"), cmd, __FILE__, __LINE__, gcry_strerror(rc)); } while(0)
/**
unsigned int idx;
list = gcry_sexp_find_token (sexp, topname, 0);
- if (! list)
- return 1;
+ if (! list)
+ return 1;
l2 = gcry_sexp_cadr (list);
gcry_sexp_release (list);
list = l2;
- if (! list)
- return 2;
+ if (! list)
+ return 2;
idx = 0;
for (s = elems; *s; s++, idx++)
/**
- * If target != size, move target bytes to the end of the size-sized
- * buffer and zero out the first target-size bytes.
+ * 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 the buffer
+ * @param size number of bytes in @a buf
* @param target target size of the buffer
*/
static void
/**
* Output the given MPI value to the given buffer.
- *
+ *
* @param buf where to output to
- * @param size number of bytes in buf
- * @param val value to write to buf
+ * @param size number of bytes in @a buf
+ * @param val value to write to @a buf
*/
static void
mpi_print (unsigned char *buf,
int rc;
if (0 != (rc = gcry_mpi_scan (result,
- GCRYMPI_FMT_USG,
+ GCRYMPI_FMT_USG,
data, size, &size)))
{
LOG_GCRY (GNUNET_ERROR_TYPE_ERROR, "gcry_mpi_scan", rc);
gcry_mpi_release (d);
if (0 != rc)
{
- LOG_GCRY (GNUNET_ERROR_TYPE_ERROR, "gcry_sexp_build", rc);
+ LOG_GCRY (GNUNET_ERROR_TYPE_ERROR, "gcry_sexp_build", rc);
GNUNET_assert (0);
}
#if EXTRA_CHECKS
* @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_sign_key (gcry_mpi_point_t q,
+ gcry_ctx_t ctx,
+ struct GNUNET_CRYPTO_EccPublicSignKey *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_key (gcry_mpi_point_t q,
- gcry_ctx_t ctx,
- struct GNUNET_CRYPTO_EccPublicKey *pub)
+point_to_public_encrypt_key (gcry_mpi_point_t q,
+ gcry_ctx_t ctx,
+ struct GNUNET_CRYPTO_EccPublicEncryptKey *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))
* @param pub where to write the public key
*/
void
-GNUNET_CRYPTO_ecc_key_get_public (const struct GNUNET_CRYPTO_EccPrivateKey *priv,
- struct GNUNET_CRYPTO_EccPublicKey *pub)
+GNUNET_CRYPTO_ecc_key_get_public_for_signature (const struct GNUNET_CRYPTO_EccPrivateKey *priv,
+ struct GNUNET_CRYPTO_EccPublicSignKey *pub)
{
gcry_sexp_t sexp;
gcry_ctx_t ctx;
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_key (q, ctx, pub);
+ point_to_public_sign_key (q, ctx, pub);
+ gcry_ctx_release (ctx);
+ gcry_mpi_point_release (q);
+}
+
+
+/**
+ * Extract the public key for the given private key.
+ *
+ * @param priv the private key
+ * @param pub where to write the public key
+ */
+void
+GNUNET_CRYPTO_ecc_key_get_public_for_encryption (const struct GNUNET_CRYPTO_EccPrivateKey *priv,
+ struct GNUNET_CRYPTO_EccPublicEncryptKey *pub)
+{
+ gcry_sexp_t sexp;
+ gcry_ctx_t ctx;
+ gcry_mpi_point_t q;
+
+ sexp = decode_private_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_encrypt_key (q, ctx, pub);
gcry_ctx_release (ctx);
gcry_mpi_point_release (q);
}
* Convert a public key to a string.
*
* @param pub key to convert
- * @return string representing 'pub'
+ * @return string representing @a pub
*/
char *
-GNUNET_CRYPTO_ecc_public_key_to_string (const struct GNUNET_CRYPTO_EccPublicKey *pub)
+GNUNET_CRYPTO_ecc_public_sign_key_to_string (const struct GNUNET_CRYPTO_EccPublicSignKey *pub)
{
char *pubkeybuf;
- size_t keylen = (sizeof (struct GNUNET_CRYPTO_EccPublicKey)) * 8;
+ size_t keylen = (sizeof (struct GNUNET_CRYPTO_EccPublicSignKey)) * 8;
char *end;
if (keylen % 5 > 0)
keylen += 5 - keylen % 5;
keylen /= 5;
pubkeybuf = GNUNET_malloc (keylen + 1);
- end = GNUNET_STRINGS_data_to_string ((unsigned char *) pub,
- sizeof (struct GNUNET_CRYPTO_EccPublicKey),
- pubkeybuf,
+ end = GNUNET_STRINGS_data_to_string ((unsigned char *) pub,
+ sizeof (struct GNUNET_CRYPTO_EccPublicSignKey),
+ pubkeybuf,
keylen);
if (NULL == end)
{
* Convert a string representing a public key to a public key.
*
* @param enc encoded public key
- * @param enclen number of bytes in enc (without 0-terminator)
+ * @param enclen number of bytes in @a enc (without 0-terminator)
* @param pub where to store the public key
- * @return GNUNET_OK on success
+ * @return #GNUNET_OK on success
*/
int
-GNUNET_CRYPTO_ecc_public_key_from_string (const char *enc,
+GNUNET_CRYPTO_ecc_public_sign_key_from_string (const char *enc,
size_t enclen,
- struct GNUNET_CRYPTO_EccPublicKey *pub)
+ struct GNUNET_CRYPTO_EccPublicSignKey *pub)
{
- size_t keylen = (sizeof (struct GNUNET_CRYPTO_EccPublicKey)) * 8;
+ size_t keylen = (sizeof (struct GNUNET_CRYPTO_EccPublicSignKey)) * 8;
if (keylen % 5 > 0)
keylen += 5 - keylen % 5;
if (GNUNET_OK != GNUNET_STRINGS_string_to_data (enc, enclen,
pub,
- sizeof (struct GNUNET_CRYPTO_EccPublicKey)))
+ sizeof (struct GNUNET_CRYPTO_EccPublicSignKey)))
return GNUNET_SYSERR;
return GNUNET_OK;
}
* @return NULL on error
*/
static gcry_sexp_t
-decode_public_key (const struct GNUNET_CRYPTO_EccPublicKey *pub)
+decode_public_sign_key (const struct GNUNET_CRYPTO_EccPublicSignKey *pub)
{
gcry_sexp_t pub_sexp;
gcry_mpi_t q_x;
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_point_set (q, q_x, q_y, GCRYMPI_CONST_ONE);
gcry_mpi_release (q_x);
gcry_mpi_release (q_y);
}
+/**
+ * @ingroup crypto
+ * Clear memory that was used to store a private key.
+ *
+ * @param pk location of the key
+ */
+void
+GNUNET_CRYPTO_ecc_key_clear (struct GNUNET_CRYPTO_EccPrivateKey *pk)
+{
+ memset (pk, 0, sizeof (struct GNUNET_CRYPTO_EccPrivateKey));
+}
+
+
/**
* Create a new private key. Caller must free return value.
*
if (once)
return &anonymous;
- mpi_print (anonymous.d,
- sizeof (anonymous.d),
+ mpi_print (anonymous.d,
+ sizeof (anonymous.d),
GCRYMPI_CONST_ONE);
once = 1;
return &anonymous;
* Create a new private key by reading our peer's key from
* the file specified in the configuration.
*
+ * @param cfg the configuration to use
* @return new private key, NULL on error (for example,
* permission denied)
*/
struct GNUNET_CRYPTO_EccPrivateKey *priv;
char *fn;
- if (GNUNET_OK !=
+ if (GNUNET_OK !=
GNUNET_CONFIGURATION_get_value_filename (cfg, "PEER", "PRIVATE_KEY", &fn))
return NULL;
priv = GNUNET_CRYPTO_ecc_key_create_from_file (fn);
*
* @param cfg configuration to use
* @param dst pointer to where to write the peer identity
- * @return GNUNET_OK on success, GNUNET_SYSERR if the identity
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR if the identity
* could not be retrieved
*/
int
-GNUNET_CRYPTO_get_host_identity (const struct GNUNET_CONFIGURATION_Handle *cfg,
+GNUNET_CRYPTO_get_peer_identity (const struct GNUNET_CONFIGURATION_Handle *cfg,
struct GNUNET_PeerIdentity *dst)
{
struct GNUNET_CRYPTO_EccPrivateKey *priv;
- struct GNUNET_CRYPTO_EccPublicKey pub;
if (NULL == (priv = GNUNET_CRYPTO_ecc_key_create_from_configuration (cfg)))
{
_("Could not load peer's private key\n"));
return GNUNET_SYSERR;
}
- GNUNET_CRYPTO_ecc_key_get_public (priv, &pub);
+ GNUNET_CRYPTO_ecc_key_get_public_for_signature (priv, &dst->public_key);
GNUNET_free (priv);
- GNUNET_CRYPTO_hash (&pub, sizeof (pub), &dst->hashPubKey);
return GNUNET_OK;
}
* @param priv private key to use for the signing
* @param purpose what to sign (size, purpose)
* @param sig where to write the signature
- * @return GNUNET_SYSERR on error, GNUNET_OK on success
+ * @return #GNUNET_SYSERR on error, #GNUNET_OK on success
*/
int
GNUNET_CRYPTO_ecc_sign (const struct GNUNET_CRYPTO_EccPrivateKey *priv,
* @param validate block to validate (size, purpose, data)
* @param sig signature that is being validated
* @param pub public key of the signer
- * @returns GNUNET_OK if ok, GNUNET_SYSERR if invalid
+ * @returns #GNUNET_OK if ok, #GNUNET_SYSERR if invalid
*/
int
GNUNET_CRYPTO_ecc_verify (uint32_t purpose,
const struct GNUNET_CRYPTO_EccSignaturePurpose
*validate,
const struct GNUNET_CRYPTO_EccSignature *sig,
- const struct GNUNET_CRYPTO_EccPublicKey *pub)
+ const struct GNUNET_CRYPTO_EccPublicSignKey *pub)
{
gcry_sexp_t data;
gcry_sexp_t sig_sexpr;
/* 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,
+ if (0 != (rc = gcry_sexp_build (&sig_sexpr, NULL,
"(sig-val(ecdsa(r %m)(s %m)))",
r, s)))
{
gcry_mpi_release (r);
gcry_mpi_release (s);
data = data_to_pkcs1 (validate);
- if (! (pub_sexpr = decode_public_key (pub)))
+ if (! (pub_sexpr = decode_public_sign_key (pub)))
{
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_encrypt_key (const struct GNUNET_CRYPTO_EccPublicEncryptKey *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 ECC key.
*
* @param priv private key to use for the ECDH (x)
* @param pub public key to use for the ECDH (yG)
* @param key_material where to write the key material (xyG)
- * @return GNUNET_SYSERR on error, GNUNET_OK on success
+ * @return #GNUNET_SYSERR on error, #GNUNET_OK on success
*/
int
GNUNET_CRYPTO_ecc_ecdh (const struct GNUNET_CRYPTO_EccPrivateKey *priv,
- const struct GNUNET_CRYPTO_EccPublicKey *pub,
+ const struct GNUNET_CRYPTO_EccPublicEncryptKey *pub,
struct GNUNET_HashCode *key_material)
-{
- size_t slen;
- unsigned char sdata_buf[2048]; /* big enough to print
- dh-shared-secret as
- S-expression */
+{
gcry_mpi_point_t result;
gcry_mpi_point_t q;
gcry_mpi_t d;
gcry_ctx_t ctx;
gcry_sexp_t pub_sexpr;
- gcry_sexp_t ecdh_sexp;
gcry_mpi_t result_x;
gcry_mpi_t result_y;
- int rc;
+ unsigned char xbuf[256 / 8];
/* first, extract the q = dP value from the public key */
- if (! (pub_sexpr = decode_public_key (pub)))
+ if (! (pub_sexpr = decode_public_encrypt_key (pub)))
return GNUNET_SYSERR;
GNUNET_assert (0 == gcry_mpi_ec_new (&ctx, pub_sexpr, NULL));
gcry_sexp_release (pub_sexpr);
}
gcry_mpi_point_release (result);
gcry_ctx_release (ctx);
- if (0 != (rc = gcry_sexp_build (&ecdh_sexp, NULL,
- "(dh-shared-secret (x %m)(y %m))",
- result_x,
- result_y)))
- {
- LOG_GCRY (GNUNET_ERROR_TYPE_ERROR, "gcry_sexp_build", rc);
- gcry_mpi_release (result_x);
- gcry_mpi_release (result_y);
- return GNUNET_SYSERR;
- }
+
+ mpi_print (xbuf, sizeof (xbuf), result_x);
+ GNUNET_CRYPTO_hash (xbuf, sizeof (xbuf), key_material);
gcry_mpi_release (result_x);
gcry_mpi_release (result_y);
- slen = gcry_sexp_sprint (ecdh_sexp,
- GCRYSEXP_FMT_DEFAULT,
- sdata_buf, sizeof (sdata_buf));
- GNUNET_assert (0 != slen);
- gcry_sexp_release (ecdh_sexp);
- /* finally, get a string of the resulting S-expression and hash it
- to generate the key material */
- GNUNET_CRYPTO_hash (sdata_buf, slen, key_material);
return GNUNET_OK;
}
/**
- * Derive the 'h' value for key derivation, where
+ * Derive the 'h' value for key derivation, where
* 'h = H(l,P)'.
*
* @param pub public key for deriviation
* @param context additional context to use for HKDF of 'h';
* typically the name of the subsystem/application
* @return h value
- */
-static gcry_mpi_t
-derive_h (const struct GNUNET_CRYPTO_EccPublicKey *pub,
+ */
+static gcry_mpi_t
+derive_h (const struct GNUNET_CRYPTO_EccPublicSignKey *pub,
const char *label,
const char *context)
{
const char *label,
const char *context)
{
- struct GNUNET_CRYPTO_EccPublicKey pub;
+ struct GNUNET_CRYPTO_EccPublicSignKey pub;
struct GNUNET_CRYPTO_EccPrivateKey *ret;
gcry_mpi_t h;
gcry_mpi_t x;
GNUNET_assert (0 == gcry_mpi_ec_new (&ctx, NULL, CURVE));
n = gcry_mpi_ec_get_mpi ("n", ctx, 1);
- GNUNET_CRYPTO_ecc_key_get_public (priv, &pub);
+ GNUNET_CRYPTO_ecc_key_get_public_for_signature (priv, &pub);
h = derive_h (&pub, label, context);
mpi_scan (&x, priv->d, sizeof (priv->d));
d = gcry_mpi_new (256);
* @param result where to write the derived public key
*/
void
-GNUNET_CRYPTO_ecc_public_key_derive (const struct GNUNET_CRYPTO_EccPublicKey *pub,
+GNUNET_CRYPTO_ecc_public_key_derive (const struct GNUNET_CRYPTO_EccPublicSignKey *pub,
const char *label,
const char *context,
- struct GNUNET_CRYPTO_EccPublicKey *result)
+ struct GNUNET_CRYPTO_EccPublicSignKey *result)
{
gcry_ctx_t ctx;
gcry_mpi_t h;
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));
gcry_mpi_release (n);
gcry_mpi_point_release (q);
/* convert point 'v' to public key that we return */
- point_to_public_key (v, ctx, result);
+ point_to_public_sign_key (v, ctx, result);
gcry_mpi_point_release (v);
gcry_ctx_release (ctx);
}
projects / oweals / gnunet.git / blobdiff