X-Git-Url: https://bearssl.org/gitweb//home/git/?p=BearSSL;a=blobdiff_plain;f=src%2Fx509%2Fencode_ec_rawder.c;fp=src%2Fx509%2Fencode_ec_rawder.c;h=5985909adebadd9cdb231307fa9347706a7cb2ac;hp=0000000000000000000000000000000000000000;hb=d8fa415fcabecb7d7c8461d8edbe2f265911e72c;hpb=cfbc702d3d64c209784b664eeab8867b603f4d4c

diff --git a/src/x509/encode_ec_rawder.c b/src/x509/encode_ec_rawder.c
new file mode 100644
index 0000000..5985909
--- /dev/null
+++ b/src/x509/encode_ec_rawder.c
@@ -0,0 +1,161 @@
+/*
+ * 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"
+
+/* see inner.h */
+const unsigned char *
+br_get_curve_OID(int curve)
+{
+	static const unsigned char OID_secp256r1[] = {
+		0x08, 0x2a, 0x86, 0x48, 0xce, 0x3d, 0x03, 0x01, 0x07
+	};
+	static const unsigned char OID_secp384r1[] = {
+		0x05, 0x2b, 0x81, 0x04, 0x00, 0x22
+	};
+	static const unsigned char OID_secp521r1[] = {
+		0x05, 0x2b, 0x81, 0x04, 0x00, 0x23
+	};
+
+	switch (curve) {
+	case BR_EC_secp256r1:  return OID_secp256r1;
+	case BR_EC_secp384r1:  return OID_secp384r1;
+	case BR_EC_secp521r1:  return OID_secp521r1;
+	default:
+		return NULL;
+	}
+}
+
+/* see inner.h */
+size_t
+br_encode_ec_raw_der_inner(void *dest,
+	const br_ec_private_key *sk, const br_ec_public_key *pk,
+	int include_curve_oid)
+{
+	/*
+	 * ASN.1 format:
+	 *
+	 *   ECPrivateKey ::= SEQUENCE {
+	 *     version        INTEGER { ecPrivkeyVer1(1) } (ecPrivkeyVer1),
+	 *     privateKey     OCTET STRING,
+	 *     parameters [0] ECParameters {{ NamedCurve }} OPTIONAL,
+	 *     publicKey  [1] BIT STRING OPTIONAL
+	 *   }
+	 *
+	 * The tages '[0]' and '[1]' are explicit. The 'ECParameters'
+	 * is a CHOICE; in our case, it will always be an OBJECT IDENTIFIER
+	 * that identifies the curve.
+	 *
+	 * The value of the 'privateKey' field is the raw unsigned big-endian
+	 * encoding of the private key (integer modulo the curve subgroup
+	 * order); there is no INTEGER tag, and the leading bit may be 1.
+	 * Also, leading bytes of value 0x00 are _not_ removed.
+	 *
+	 * The 'publicKey' contents are the raw encoded public key point,
+	 * normally uncompressed (leading byte of value 0x04, followed
+	 * by the unsigned big-endian encodings of the X and Y coordinates,
+	 * padded to the full field length if necessary).
+	 */
+
+	size_t len_version, len_privateKey, len_parameters, len_publicKey;
+	size_t len_publicKey_bits, len_seq;
+	const unsigned char *oid;
+
+	if (include_curve_oid) {
+		oid = br_get_curve_OID(sk->curve);
+		if (oid == NULL) {
+			return 0;
+		}
+	} else {
+		oid = NULL;
+	}
+	len_version = 3;
+	len_privateKey = 1 + len_of_len(sk->xlen) + sk->xlen;
+	if (include_curve_oid) {
+		len_parameters = 4 + oid[0];
+	} else {
+		len_parameters = 0;
+	}
+	if (pk == NULL) {
+		len_publicKey = 0;
+		len_publicKey_bits = 0;
+	} else {
+		len_publicKey_bits = 2 + len_of_len(pk->qlen) + pk->qlen;
+		len_publicKey = 1 + len_of_len(len_publicKey_bits)
+			+ len_publicKey_bits;
+	}
+	len_seq = len_version + len_privateKey + len_parameters + len_publicKey;
+	if (dest == NULL) {
+		return 1 + len_of_len(len_seq) + len_seq;
+	} else {
+		unsigned char *buf;
+		size_t lenlen;
+
+		buf = dest;
+		*buf ++ = 0x30;  /* SEQUENCE tag */
+		lenlen = br_asn1_encode_length(buf, len_seq);
+		buf += lenlen;
+
+		/* version */
+		*buf ++ = 0x02;
+		*buf ++ = 0x01;
+		*buf ++ = 0x01;
+
+		/* privateKey */
+		*buf ++ = 0x04;
+		buf += br_asn1_encode_length(buf, sk->xlen);
+		memcpy(buf, sk->x, sk->xlen);
+		buf += sk->xlen;
+
+		/* parameters */
+		if (include_curve_oid) {
+			*buf ++ = 0xA0;
+			*buf ++ = oid[0] + 2;
+			*buf ++ = 0x06;
+			memcpy(buf, oid, oid[0] + 1);
+			buf += oid[0] + 1;
+		}
+
+		/* publicKey */
+		if (pk != NULL) {
+			*buf ++ = 0xA1;
+			buf += br_asn1_encode_length(buf, len_publicKey_bits);
+			*buf ++ = 0x03;
+			buf += br_asn1_encode_length(buf, pk->qlen + 1);
+			*buf ++ = 0x00;
+			memcpy(buf, pk->q, pk->qlen);
+			/* buf += pk->qlen; */
+		}
+
+		return 1 + lenlen + len_seq;
+	}
+}
+
+/* see bearssl_x509.h */
+size_t
+br_encode_ec_raw_der(void *dest,
+	const br_ec_private_key *sk, const br_ec_public_key *pk)
+{
+	return br_encode_ec_raw_der_inner(dest, sk, pk, 1);
+}