diff --git a/crypto.c b/crypto.c
index e96fd0e..4b6419a 100644
--- a/crypto.c
+++ b/crypto.c
@@ -614,8 +614,9 @@ smc_sum (gcry_mpi_point_t out,
  * public multiplicative key share
  *
  * @param[in,out] ad Pointer to the BRANDT_Auction struct to operate on
- * @param[out] buflen \todo
- * @return \todo
+ * @param[out] buflen Size of the returned buffer in bytes
+ * @return A buffer containing the multiplicative public key share which needs
+ * to be broadcast
  */
 unsigned char *
 smc_gen_keyshare (struct BRANDT_Auction *ad, size_t *buflen)