X-Git-Url: https://www.bearssl.org/gitweb//home/git/?p=BearSSL;a=blobdiff_plain;f=src%2Fec%2Fec_pubkey.c;fp=src%2Fec%2Fec_pubkey.c;h=383ff286c74dcb0684b9421ffe21abf7d9e3956c;hp=0000000000000000000000000000000000000000;hb=d8fa415fcabecb7d7c8461d8edbe2f265911e72c;hpb=cfbc702d3d64c209784b664eeab8867b603f4d4c

diff --git a/src/ec/ec_pubkey.c b/src/ec/ec_pubkey.c
new file mode 100644
index 0000000..383ff28
--- /dev/null
+++ b/src/ec/ec_pubkey.c
@@ -0,0 +1,85 @@
+/*
+ * Copyright (c) 2018 Thomas Pornin <pornin@bolet.org>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining 
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be 
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include "inner.h"
+
+static const unsigned char POINT_LEN[] = {
+	  0,   /* 0: not a valid curve ID */
+	 43,   /* sect163k1 */
+	 43,   /* sect163r1 */
+	 43,   /* sect163r2 */
+	 51,   /* sect193r1 */
+	 51,   /* sect193r2 */
+	 61,   /* sect233k1 */
+	 61,   /* sect233r1 */
+	 61,   /* sect239k1 */
+	 73,   /* sect283k1 */
+	 73,   /* sect283r1 */
+	105,   /* sect409k1 */
+	105,   /* sect409r1 */
+	145,   /* sect571k1 */
+	145,   /* sect571r1 */
+	 41,   /* secp160k1 */
+	 41,   /* secp160r1 */
+	 41,   /* secp160r2 */
+	 49,   /* secp192k1 */
+	 49,   /* secp192r1 */
+	 57,   /* secp224k1 */
+	 57,   /* secp224r1 */
+	 65,   /* secp256k1 */
+	 65,   /* secp256r1 */
+	 97,   /* secp384r1 */
+	133,   /* secp521r1 */
+	 65,   /* brainpoolP256r1 */
+	 97,   /* brainpoolP384r1 */
+	129,   /* brainpoolP512r1 */
+	 32,   /* curve25519 */
+	 56,   /* curve448 */
+};
+
+/* see bearssl_ec.h */
+size_t
+br_ec_compute_pub(const br_ec_impl *impl, br_ec_public_key *pk,
+	void *kbuf, const br_ec_private_key *sk)
+{
+	int curve;
+	size_t len;
+
+	curve = sk->curve;
+	if (curve < 0 || curve >= 32 || curve >= (int)(sizeof POINT_LEN)
+		|| ((impl->supported_curves >> curve) & 1) == 0)
+	{
+		return 0;
+	}
+	if (kbuf == NULL) {
+		return POINT_LEN[curve];
+	}
+	len = impl->mulgen(kbuf, sk->x, sk->xlen, curve);
+	if (pk != NULL) {
+		pk->curve = curve;
+		pk->q = kbuf;
+		pk->qlen = len;
+	}
+	return len;
+}