Clear sensitive data in ED25519_sign
@@ -4599,7 +4599,9 @@ int ED25519_sign(uint8_t *out_sig, const uint8_t *message, size_t message_len,
uint8_t hram[SHA512_DIGEST_LENGTH];
SHA512_CTX hash_ctx;
- SHA512(private_key, 32, az);
+ SHA512_Init(&hash_ctx);
+ SHA512_Update(&hash_ctx, private_key, 32);
+ SHA512_Final(az, &hash_ctx);
az[0] &= 248;
az[31] &= 63;
@@ -4623,6 +4625,10 @@ int ED25519_sign(uint8_t *out_sig, const uint8_t *message, size_t message_len,
x25519_sc_reduce(hram);
sc_muladd(out_sig + 32, hram, az, nonce);
+ OPENSSL_cleanse(&hash_ctx, sizeof(hash_ctx));
+ OPENSSL_cleanse(nonce, sizeof(nonce));
+ OPENSSL_cleanse(az, sizeof(az));
+
return 1;
}
