1 files changed, 17 insertions, 0 deletions
diff --git a/src/include/taler_crypto_lib.h b/src/include/taler_crypto_lib.h
index 4126894a1..5f1425077 100644
--- a/src/include/taler_crypto_lib.h
+++ b/src/include/taler_crypto_lib.h
@@ -469,6 +469,23 @@ TALER_link_decrypt_secret2 (const struct TALER_EncryptedLinkSecretP *secret_enc,
 
 
 /**
+ * Given the coin and the transfer private keys, compute the
+ * transfer secret.  (Technically, we only need one of the two
+ * private keys, but the caller currently trivially only has
+ * the two private keys, so we derive one of the public keys
+ * internally to this function.)
+ *
+ * @param coin_priv coin key
+ * @param trans_priv transfer private key
+ * @param[out] computed transfer secret
+ */
+void
+TALER_link_derive_transfer_secret (const struct TALER_CoinSpendPrivateKeyP *coin_priv,
+                                   const struct TALER_TransferPrivateKeyP *trans_priv,
+                                   struct TALER_TransferSecretP *ts);
+
+
+/**
  * Encrypt the shared @a secret to generate the encrypted link secret.
  * Also creates the transfer key.
  *