1 files changed, 66 insertions, 0 deletions
diff --git a/src/boringssl_ed25519_ops.c b/src/boringssl_ed25519_ops.c
new file mode 100644
index 0000000..a1b9797
--- /dev/null
+++ b/src/boringssl_ed25519_ops.c
@@ -0,0 +1,66 @@
+// Copyright 2022 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License"); you may not
+// use this file except in compliance with the License. You may obtain a copy of
+// the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+// License for the specific language governing permissions and limitations under
+// the License.
+
+// An implementation of the ed25519 signature operations using boringssl.
+
+#include <stdint.h>
+
+#include "dice/dice.h"
+#include "dice/ops.h"
+#include "openssl/curve25519.h"
+#include "openssl/evp.h"
+
+#if DICE_PRIVATE_KEY_SEED_SIZE != 32
+#error "Private key seed is expected to be 32 bytes."
+#endif
+#if DICE_PUBLIC_KEY_SIZE != 32
+#error "Ed25519 needs 32 bytes to store the public key."
+#endif
+#if DICE_PRIVATE_KEY_SIZE != 64
+#error "This Ed25519 implementation needs 64 bytes for the private key."
+#endif
+#if DICE_SIGNATURE_SIZE != 64
+#error "Ed25519 needs 64 bytes to store the signature."
+#endif
+
+DiceResult DiceKeypairFromSeed(void* context_not_used,
+                               const uint8_t seed[DICE_PRIVATE_KEY_SEED_SIZE],
+                               uint8_t public_key[DICE_PUBLIC_KEY_SIZE],
+                               uint8_t private_key[DICE_PRIVATE_KEY_SIZE]) {
+  (void)context_not_used;
+  ED25519_keypair_from_seed(public_key, private_key, seed);
+  return kDiceResultOk;
+}
+
+DiceResult DiceSign(void* context_not_used, const uint8_t* message,
+                    size_t message_size,
+                    const uint8_t private_key[DICE_PRIVATE_KEY_SIZE],
+                    uint8_t signature[DICE_SIGNATURE_SIZE]) {
+  (void)context_not_used;
+  if (1 != ED25519_sign(signature, message, message_size, private_key)) {
+    return kDiceResultPlatformError;
+  }
+  return kDiceResultOk;
+}
+
+DiceResult DiceVerify(void* context_not_used, const uint8_t* message,
+                      size_t message_size,
+                      const uint8_t signature[DICE_SIGNATURE_SIZE],
+                      const uint8_t public_key[DICE_PUBLIC_KEY_SIZE]) {
+  (void)context_not_used;
+  if (1 != ED25519_verify(message, message_size, signature, public_key)) {
+    return kDiceResultPlatformError;
+  }
+  return kDiceResultOk;
+}