1 files changed, 172 insertions, 0 deletions
diff --git a/src/eddsa.c b/src/eddsa.c
new file mode 100644
index 000000000000..89b84c5a6bd4
--- /dev/null
+++ b/src/eddsa.c
@@ -0,0 +1,172 @@
+/*
+ * Copyright (c) 2019 Yubico AB. All rights reserved.
+ * Use of this source code is governed by a BSD-style
+ * license that can be found in the LICENSE file.
+ */
+
+#include <openssl/bn.h>
+#include <openssl/obj_mac.h>
+
+#include "fido.h"
+#include "fido/eddsa.h"
+
+#if defined(LIBRESSL_VERSION_NUMBER) || OPENSSL_VERSION_NUMBER < 0x10101000L
+EVP_PKEY *
+EVP_PKEY_new_raw_public_key(int type, ENGINE *e, const unsigned char *key,
+    size_t keylen)
+{
+	(void)type;
+	(void)e;
+	(void)key;
+	(void)keylen;
+
+	fido_log_debug("%s: unimplemented", __func__);
+
+	return (NULL);
+}
+
+int
+EVP_PKEY_get_raw_public_key(const EVP_PKEY *pkey, unsigned char *pub,
+    size_t *len)
+{
+	(void)pkey;
+	(void)pub;
+	(void)len;
+
+	fido_log_debug("%s: unimplemented", __func__);
+
+	return (0);
+}
+
+int
+EVP_DigestVerify(EVP_MD_CTX *ctx, const unsigned char *sigret, size_t siglen,
+    const unsigned char *tbs, size_t tbslen)
+{
+	(void)ctx;
+	(void)sigret;
+	(void)siglen;
+	(void)tbs;
+	(void)tbslen;
+
+	fido_log_debug("%s: unimplemented", __func__);
+
+	return (0);
+}
+#endif /* LIBRESSL_VERSION_NUMBER || OPENSSL_VERSION_NUMBER < 0x10101000L */
+
+#if OPENSSL_VERSION_NUMBER < 0x10100000L
+EVP_MD_CTX *
+EVP_MD_CTX_new(void)
+{
+	fido_log_debug("%s: unimplemented", __func__);
+
+	return (NULL);
+}
+
+void
+EVP_MD_CTX_free(EVP_MD_CTX *ctx)
+{
+	(void)ctx;
+}
+#endif /* OPENSSL_VERSION_NUMBER < 0x10100000L */
+
+static int
+decode_coord(const cbor_item_t *item, void *xy, size_t xy_len)
+{
+	if (cbor_isa_bytestring(item) == false ||
+	    cbor_bytestring_is_definite(item) == false ||
+	    cbor_bytestring_length(item) != xy_len) {
+		fido_log_debug("%s: cbor type", __func__);
+		return (-1);
+	}
+
+	memcpy(xy, cbor_bytestring_handle(item), xy_len);
+
+	return (0);
+}
+
+static int
+decode_pubkey_point(const cbor_item_t *key, const cbor_item_t *val, void *arg)
+{
+	eddsa_pk_t *k = arg;
+
+	if (cbor_isa_negint(key) == false ||
+	    cbor_int_get_width(key) != CBOR_INT_8)
+		return (0); /* ignore */
+
+	switch (cbor_get_uint8(key)) {
+	case 1: /* x coordinate */
+		return (decode_coord(val, &k->x, sizeof(k->x)));
+	}
+
+	return (0); /* ignore */
+}
+
+int
+eddsa_pk_decode(const cbor_item_t *item, eddsa_pk_t *k)
+{
+	if (cbor_isa_map(item) == false ||
+	    cbor_map_is_definite(item) == false ||
+	    cbor_map_iter(item, k, decode_pubkey_point) < 0) {
+		fido_log_debug("%s: cbor type", __func__);
+		return (-1);
+	}
+
+	return (0);
+}
+
+eddsa_pk_t *
+eddsa_pk_new(void)
+{
+	return (calloc(1, sizeof(eddsa_pk_t)));
+}
+
+void
+eddsa_pk_free(eddsa_pk_t **pkp)
+{
+	eddsa_pk_t *pk;
+
+	if (pkp == NULL || (pk = *pkp) == NULL)
+		return;
+
+	freezero(pk, sizeof(*pk));
+	*pkp = NULL;
+}
+
+int
+eddsa_pk_from_ptr(eddsa_pk_t *pk, const void *ptr, size_t len)
+{
+	if (len < sizeof(*pk))
+		return (FIDO_ERR_INVALID_ARGUMENT);
+
+	memcpy(pk, ptr, sizeof(*pk));
+
+	return (FIDO_OK);
+}
+
+EVP_PKEY *
+eddsa_pk_to_EVP_PKEY(const eddsa_pk_t *k)
+{
+	EVP_PKEY *pkey = NULL;
+
+	if ((pkey = EVP_PKEY_new_raw_public_key(EVP_PKEY_ED25519, NULL, k->x,
+	    sizeof(k->x))) == NULL)
+		fido_log_debug("%s: EVP_PKEY_new_raw_public_key", __func__);
+
+	return (pkey);
+}
+
+int
+eddsa_pk_from_EVP_PKEY(eddsa_pk_t *pk, const EVP_PKEY *pkey)
+{
+	size_t len = 0;
+
+	if (EVP_PKEY_get_raw_public_key(pkey, NULL, &len) != 1 ||
+	    len != sizeof(pk->x))
+		return (FIDO_ERR_INTERNAL);
+	if (EVP_PKEY_get_raw_public_key(pkey, pk->x, &len) != 1 ||
+	    len != sizeof(pk->x))
+		return (FIDO_ERR_INTERNAL);
+
+	return (FIDO_OK);
+}