implementing varsize link data

7 files changed, 266 insertions, 129 deletions

diff --git a/src/mint/mint.h b/src/mint/mint.h
index b194be687..010ff4d5f 100644
--- a/src/mint/mint.h
+++ b/src/mint/mint.h
@@ -115,43 +115,89 @@ struct CollectableBlindcoin
 };
 
 
+/**
+ * Global information for a refreshing session.
+ */
 struct RefreshSession
 {
+  /**
+   * Signature over the commitments by the client.
+   */
   struct GNUNET_CRYPTO_EddsaSignature commit_sig;
+
+  /**
+   * Public key of the refreshing session, used to sign
+   * the client's commit message.
+   */
   struct GNUNET_CRYPTO_EddsaPublicKey session_pub;
-  int has_commit_sig;
+
+  /**
+   * Number of coins we are melting.
+   */
   uint16_t num_oldcoins;
+
+  /**
+   * Number of new coins we are creating.
+   */
   uint16_t num_newcoins;
+
+  /**
+   * Number of parallel operations we perform for the cut and choose.
+   * (must be greater or equal to three for security).
+   */
   uint16_t kappa;
+
+  /**
+   * Index (smaller @e kappa) which the mint has chosen to not
+   * have revealed during cut and choose.
+   */
   uint16_t noreveal_index;
+
+  /**
+   * FIXME.
+   */
+  int has_commit_sig;
+
+  /**
+   * FIXME.
+   */
   uint8_t reveal_ok;
 };
 
 
 /**
- * FIXME
+ * For each (old) coin being melted, we have a `struct
+ * RefreshCommitLink` that allows the user to find the shared secret
+ * to decrypt the respective refresh links for the new coins in the
+ * `struct RefreshCommitCoin`.
  */
 struct RefreshCommitLink
 {
-  struct GNUNET_CRYPTO_EddsaPublicKey session_pub;
+  /**
+   * Transfer public key (FIXME: explain!)
+   */
   struct GNUNET_CRYPTO_EcdsaPublicKey transfer_pub;
+
+  /**
+   * FIXME: this can't be exactly the shared secret, must
+   * be a commitment to it or something.
+   */
   struct GNUNET_HashCode shared_secret;
-  uint16_t cnc_index;
-  uint16_t oldcoin_index;
 };
 
 
 /**
- * FIXME
+ * We have as many `struct RefreshCommitCoin` as there are new
+ * coins being created by the refresh.
  */
 struct RefreshCommitCoin
 {
+
   /**
-   * Refresh session's public key.
+   * Encrypted data allowing those able to decrypt it to derive
+   * the private keys of the new coins created by the refresh.
    */
-  struct GNUNET_CRYPTO_EddsaPublicKey session_pub;
-
-  struct TALER_RefreshLinkEncrypted refresh_link;
+  struct TALER_RefreshLinkEncrypted *refresh_link;
 
   /**
    * Blinded message to be signed (in envelope), with @e coin_env_size bytes.
@@ -163,16 +209,6 @@ struct RefreshCommitCoin
    */
   size_t coin_ev_size;
 
-  /**
-   * FIXME: needed?
-   */
-  uint16_t cnc_index;
-
-  /**
-   * FIXME: needed?
-   */
-  uint16_t newcoin_index;
-
 };
 
 
diff --git a/src/mint/mint_db.c b/src/mint/mint_db.c
index eb83e61a9..2b0ebc955 100644
--- a/src/mint/mint_db.c
+++ b/src/mint/mint_db.c
@@ -1131,7 +1131,8 @@ TALER_MINT_DB_insert_known_coin (PGconn *db_conn,
 
 
 int
-TALER_MINT_DB_upsert_known_coin (PGconn *db_conn, struct KnownCoin *known_coin)
+TALER_MINT_DB_upsert_known_coin (PGconn *db_conn,
+                                 struct KnownCoin *known_coin)
 {
   int ret;
   ret = TALER_MINT_DB_update_known_coin (db_conn, known_coin);
@@ -1146,58 +1147,38 @@ TALER_MINT_DB_upsert_known_coin (PGconn *db_conn, struct KnownCoin *known_coin)
 }
 
 
+/**
+ * Store the commitment to the given (encrypted) refresh link data
+ * for the given refresh session.
+ *
+ * @param db_conn database connection to use
+ * @param refresh_session_pub public key of the refresh session this
+ *        commitment belongs with
+ * @param i
+ * @param j
+ * @param commit_link link information to store
+ * @return #GNUNET_SYSERR on internal error, #GNUNET_OK on success
+ */
 int
 TALER_MINT_DB_insert_refresh_commit_link (PGconn *db_conn,
+                                          const struct GNUNET_CRYPTO_EddsaPublicKey *refresh_session_pub,
+                                          int i, int j,
                                           const struct RefreshCommitLink *commit_link)
 {
-  uint16_t cnc_index_nbo = htons (commit_link->cnc_index);
-  uint16_t oldcoin_index_nbo = htons (commit_link->oldcoin_index);
+  uint16_t cnc_index_nbo = htons (i);
+  uint16_t oldcoin_index_nbo = htons (j);
   struct TALER_DB_QueryParam params[] = {
-    TALER_DB_QUERY_PARAM_PTR(&commit_link->session_pub),
+    TALER_DB_QUERY_PARAM_PTR(refresh_session_pub),
     TALER_DB_QUERY_PARAM_PTR(&commit_link->transfer_pub),
     TALER_DB_QUERY_PARAM_PTR(&cnc_index_nbo),
     TALER_DB_QUERY_PARAM_PTR(&oldcoin_index_nbo),
-    TALER_DB_QUERY_PARAM_PTR_SIZED(&commit_link->shared_secret_enc, sizeof (struct GNUNET_HashCode)),
+    TALER_DB_QUERY_PARAM_PTR(&commit_link->shared_secret),
     TALER_DB_QUERY_PARAM_END
   };
 
-  PGresult *result = TALER_DB_exec_prepared (db_conn, "insert_refresh_commit_link", params);
-
-  if (PGRES_COMMAND_OK != PQresultStatus (result))
-  {
-    break_db_err (result);
-    PQclear (result);
-    return GNUNET_SYSERR;
-  }
-
-  if (0 != strcmp ("1", PQcmdTuples (result)))
-  {
-    GNUNET_break (0);
-    return GNUNET_SYSERR;
-  }
-
-  PQclear (result);
-  return GNUNET_OK;
-}
-
-
-int
-TALER_MINT_DB_insert_refresh_commit_coin (PGconn *db_conn,
-                                          const struct RefreshCommitCoin *commit_coin)
-{
-  uint16_t cnc_index_nbo = htons (commit_coin->cnc_index);
-  uint16_t newcoin_index_nbo = htons (commit_coin->newcoin_index);
-  struct TALER_DB_QueryParam params[] = {
-    TALER_DB_QUERY_PARAM_PTR(&commit_coin->session_pub),
-    TALER_DB_QUERY_PARAM_PTR(&commit_coin->coin_ev),
-    TALER_DB_QUERY_PARAM_PTR(&cnc_index_nbo),
-    TALER_DB_QUERY_PARAM_PTR(&newcoin_index_nbo),
-    TALER_DB_QUERY_PARAM_PTR_SIZED(&commit_coin->link_enc, sizeof (struct LinkData)),
-    TALER_DB_QUERY_PARAM_END
-  };
-
-  PGresult *result = TALER_DB_exec_prepared (db_conn, "insert_refresh_commit_coin", params);
-
+  PGresult *result = TALER_DB_exec_prepared (db_conn,
+                                             "insert_refresh_commit_link",
+                                             params);
   if (PGRES_COMMAND_OK != PQresultStatus (result))
   {
     break_db_err (result);
@@ -1233,12 +1214,9 @@ TALER_MINT_DB_get_refresh_commit_link (PGconn *db_conn,
     TALER_DB_QUERY_PARAM_END
   };
 
-  cc->cnc_index = cnc_index;
-  cc->oldcoin_index = oldcoin_index;
-  cc->session_pub = *refresh_session_pub;
-
-  PGresult *result = TALER_DB_exec_prepared (db_conn, "get_refresh_commit_link", params);
-
+  PGresult *result = TALER_DB_exec_prepared (db_conn,
+                                             "get_refresh_commit_link",
+                                             params);
   if (PGRES_TUPLES_OK != PQresultStatus (result))
   {
     break_db_err (result);
@@ -1254,8 +1232,7 @@ TALER_MINT_DB_get_refresh_commit_link (PGconn *db_conn,
 
   struct TALER_DB_ResultSpec rs[] = {
     TALER_DB_RESULT_SPEC("transfer_pub", &cc->transfer_pub),
-    TALER_DB_RESULT_SPEC_SIZED("link_secret_enc", &cc->shared_secret_enc,
-                      TALER_REFRESH_SHARED_SECRET_LENGTH),
+    TALER_DB_RESULT_SPEC("link_secret_enc", &cc->shared_secret),
     TALER_DB_RESULT_SPEC_END
   };
 
@@ -1267,7 +1244,46 @@ TALER_MINT_DB_get_refresh_commit_link (PGconn *db_conn,
   }
 
   PQclear (result);
-  return GNUNET_YES;
+  return GNUNET_OK;
+}
+
+
+int
+TALER_MINT_DB_insert_refresh_commit_coin (PGconn *db_conn,
+                                          const struct GNUNET_CRYPTO_EddsaPublicKey *refresh_session_pub,
+                                          int i, int j,
+                                          const struct RefreshCommitCoin *commit_coin)
+{
+  uint16_t cnc_index_nbo = htons (i);
+  uint16_t newcoin_index_nbo = htons (j);
+  struct TALER_DB_QueryParam params[] = {
+    TALER_DB_QUERY_PARAM_PTR(refresh_session_pub),
+    TALER_DB_QUERY_PARAM_PTR_SIZED(commit_coin->coin_ev, commit_coin->coin_ev_size),
+    TALER_DB_QUERY_PARAM_PTR(&cnc_index_nbo),
+    TALER_DB_QUERY_PARAM_PTR(&newcoin_index_nbo),
+    TALER_DB_QUERY_PARAM_PTR_SIZED(commit_coin->refresh_link->coin_priv_enc,
+                                   commit_coin->refresh_link->blinding_key_enc_size +
+                                   sizeof (struct GNUNET_CRYPTO_EcdsaPrivateKey)),
+    TALER_DB_QUERY_PARAM_END
+  };
+
+  PGresult *result = TALER_DB_exec_prepared (db_conn, "insert_refresh_commit_coin", params);
+
+  if (PGRES_COMMAND_OK != PQresultStatus (result))
+  {
+    break_db_err (result);
+    PQclear (result);
+    return GNUNET_SYSERR;
+  }
+
+  if (0 != strcmp ("1", PQcmdTuples (result)))
+  {
+    GNUNET_break (0);
+    return GNUNET_SYSERR;
+  }
+
+  PQclear (result);
+  return GNUNET_OK;
 }
 
 
@@ -1280,17 +1296,17 @@ TALER_MINT_DB_get_refresh_commit_coin (PGconn *db_conn,
 {
   uint16_t cnc_index_nbo = htons (cnc_index);
   uint16_t newcoin_index_nbo = htons (newcoin_index);
-
-  cc->cnc_index = cnc_index;
-  cc->newcoin_index = newcoin_index;
-  cc->session_pub = *refresh_session_pub;
-
   struct TALER_DB_QueryParam params[] = {
     TALER_DB_QUERY_PARAM_PTR(refresh_session_pub),
     TALER_DB_QUERY_PARAM_PTR(&cnc_index_nbo),
     TALER_DB_QUERY_PARAM_PTR(&newcoin_index_nbo),
     TALER_DB_QUERY_PARAM_END
   };
+  char *c_buf;
+  size_t c_buf_size;
+  char *rl_buf;
+  size_t rl_buf_size;
+  struct TALER_RefreshLinkEncrypted *rl;
 
   PGresult *result = TALER_DB_exec_prepared (db_conn, "get_refresh_commit_coin", params);
 
@@ -1308,19 +1324,34 @@ TALER_MINT_DB_get_refresh_commit_coin (PGconn *db_conn,
   }
 
   struct TALER_DB_ResultSpec rs[] = {
-    TALER_DB_RESULT_SPEC("coin_ev", &cc->coin_ev),
-    TALER_DB_RESULT_SPEC_SIZED("link_vector_enc", &cc->link_enc,
-                      TALER_REFRESH_LINK_LENGTH),
+    TALER_DB_RESULT_SPEC_VAR("coin_ev", &c_buf, &c_buf_size),
+    TALER_DB_RESULT_SPEC_VAR("link_vector_enc", &rl_buf, &rl_buf_size),
     TALER_DB_RESULT_SPEC_END
   };
-
   if (GNUNET_YES != TALER_DB_extract_result (result, rs, 0))
   {
     PQclear (result);
     return GNUNET_SYSERR;
   }
-
   PQclear (result);
+  if (rl_buf_size < sizeof (struct GNUNET_CRYPTO_EcdsaPrivateKey))
+  {
+    GNUNET_free (c_buf);
+    GNUNET_free (rl_buf);
+    return GNUNET_SYSERR;
+  }
+
+  rl = GNUNET_malloc (sizeof (struct TALER_RefreshLinkEncrypted) +
+                      rl_buf_size - sizeof (struct GNUNET_CRYPTO_EcdsaPrivateKey));
+  rl->blinding_key_enc = (const char *) &rl[1];
+  rl->blinding_key_enc_size = rl_buf_size - sizeof (struct GNUNET_CRYPTO_EcdsaPrivateKey);
+  memcpy (rl->coin_priv_enc,
+          rl_buf,
+          rl_buf_size);
+  GNUNET_free (rl_buf);
+  cc->refresh_link = rl;
+  cc->coin_ev = c_buf;
+  cc->coin_ev_size = c_buf_size;
   return GNUNET_YES;
 }
 
@@ -1582,15 +1613,17 @@ TALER_db_get_link (PGconn *db_conn,
 
   for (i = 0; i < PQntuples (result); i++)
   {
-    struct LinkDataEnc link_data_enc;
+    struct TALER_RefreshLinkEncrypted *link_enc;
     struct GNUNET_CRYPTO_rsa_PublicKey *denom_pub;
     struct GNUNET_CRYPTO_rsa_Signature *sig;
+    char *ld_buf;
+    size_t ld_buf_size;
     char *pk_buf;
     size_t pk_buf_size;
     char *sig_buf;
     size_t sig_buf_size;
     struct TALER_DB_ResultSpec rs[] = {
-      TALER_DB_RESULT_SPEC("link_vector_enc", &link_data_enc),
+      TALER_DB_RESULT_SPEC_VAR("link_vector_enc", &ld_buf, &ld_buf_size),
       TALER_DB_RESULT_SPEC_VAR("denom_pub", &pk_buf, &pk_buf_size),
       TALER_DB_RESULT_SPEC_VAR("ev_sig", &sig_buf, &sig_buf_size),
       TALER_DB_RESULT_SPEC_END
@@ -1602,39 +1635,59 @@ TALER_db_get_link (PGconn *db_conn,
       GNUNET_break (0);
       return GNUNET_SYSERR;
     }
+    if (ld_buf_size < sizeof (struct GNUNET_CRYPTO_EcdsaPrivateKey))
+    {
+      PQclear (result);
+      GNUNET_free (pk_buf);
+      GNUNET_free (sig_buf);
+      GNUNET_free (ld_buf);
+      GNUNET_break (0);
+      return GNUNET_SYSERR;
+    }
+    link_enc = GNUNET_malloc (sizeof (struct TALER_RefreshLinkEncrypted) +
+                              ld_buf_size - sizeof (struct GNUNET_CRYPTO_EcdsaPrivateKey));
+    link_enc->blinding_key_enc = (const char *) &link_enc[1];
+    link_enc->blinding_key_enc_size = ld_buf_size - sizeof (struct GNUNET_CRYPTO_EcdsaPrivateKey);
+    memcpy (link_enc->coin_priv_enc,
+            ld_buf,
+            ld_buf_size);
+
     sig = GNUNET_CRYPTO_rsa_signature_decode (sig_buf,
                                               sig_buf_size);
     denom_pub = GNUNET_CRYPTO_rsa_public_key_decode (pk_buf,
                                                      pk_buf_size);
     GNUNET_free (pk_buf);
     GNUNET_free (sig_buf);
+    GNUNET_free (ld_buf);
     if ( (NULL == sig) ||
          (NULL == denom_pub) )
     {
-      PQclear (result);
       if (NULL != denom_pub)
         GNUNET_CRYPTO_rsa_public_key_free (denom_pub);
       if (NULL != sig)
         GNUNET_CRYPTO_rsa_signature_free (sig);
+      GNUNET_free (link_enc);
       GNUNET_break (0);
+      PQclear (result);
       return GNUNET_SYSERR;
     }
     if (GNUNET_OK != (res = link_iter (cls,
-                                       &link_data_enc,
+                                       link_enc,
                                        denom_pub,
                                        sig)))
     {
       GNUNET_assert (GNUNET_SYSERR != res);
       GNUNET_CRYPTO_rsa_signature_free (sig);
       GNUNET_CRYPTO_rsa_public_key_free (denom_pub);
+      GNUNET_free (link_enc);
       PQclear (result);
       return res;
     }
     GNUNET_CRYPTO_rsa_signature_free (sig);
     GNUNET_CRYPTO_rsa_public_key_free (denom_pub);
+    GNUNET_free (link_enc);
   }
 
-  PQclear (result);
   return GNUNET_OK;
 }
 
@@ -1643,7 +1696,7 @@ int
 TALER_db_get_transfer (PGconn *db_conn,
                        const struct GNUNET_CRYPTO_EcdsaPublicKey *coin_pub,
                        struct GNUNET_CRYPTO_EcdsaPublicKey *transfer_pub,
-                       struct SharedSecretEnc *shared_secret_enc)
+                       struct GNUNET_HashCode *shared_secret_enc)
 {
   struct TALER_DB_QueryParam params[] = {
     TALER_DB_QUERY_PARAM_PTR(coin_pub),
@@ -1667,7 +1720,9 @@ TALER_db_get_transfer (PGconn *db_conn,
 
   if (1 != PQntuples (result))
   {
-    GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "got %d tuples for get_transfer\n", PQntuples (result));
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                "got %d tuples for get_transfer\n",
+                PQntuples (result));
     GNUNET_break (0);
     return GNUNET_SYSERR;
   }
diff --git a/src/mint/mint_db.h b/src/mint/mint_db.h
index 0f746c14d..e0c2e2e0a 100644
--- a/src/mint/mint_db.h
+++ b/src/mint/mint_db.h
@@ -122,23 +122,49 @@ TALER_MINT_DB_get_known_coin (PGconn *db_conn,
 
 
 int
-TALER_MINT_DB_upsert_known_coin (PGconn *db_conn, struct KnownCoin *known_coin);
+TALER_MINT_DB_upsert_known_coin (PGconn *db_conn,
+                                 struct KnownCoin *known_coin);
+
+
 
 
 int
-TALER_MINT_DB_insert_refresh_commit_link (PGconn *db_conn,
-                                          const struct RefreshCommitLink *commit_link);
+TALER_MINT_DB_create_refresh_session (PGconn *db_conn,
+                                      const struct GNUNET_CRYPTO_EddsaPublicKey *session_pub);
 
+
+/**
+ * Store the commitment to the given (encrypted) refresh link data
+ * for the given refresh session.
+ *
+ * @param db_conn database connection to use
+ * @param refresh_session_pub public key of the refresh session this
+ *        commitment belongs with
+ * @param i
+ * @param j
+ * @param commit_link link information to store
+ * @return #GNUNET_SYSERR on internal error, #GNUNET_OK on success
+ */
 int
-TALER_MINT_DB_insert_refresh_commit_coin (PGconn *db_conn,
-                                          const struct RefreshCommitCoin *commit_coin);
+TALER_MINT_DB_insert_refresh_commit_link (PGconn *db_conn,
+                                          const struct GNUNET_CRYPTO_EddsaPublicKey *refresh_session_pub,
+                                          int i, int j,
+                                          const struct RefreshCommitLink *commit_link);
 
 
 int
 TALER_MINT_DB_get_refresh_commit_link (PGconn *db_conn,
                                        const struct GNUNET_CRYPTO_EddsaPublicKey *refresh_session_pub,
                                        int i, int j,
-                                       struct RefreshCommitLink *commit_link);
+                                       struct RefreshCommitLink *cc);
+
+
+int
+TALER_MINT_DB_insert_refresh_commit_coin (PGconn *db_conn,
+                                          const struct GNUNET_CRYPTO_EddsaPublicKey *refresh_session_pub,
+                                          int i,
+                                          int j,
+                                          const struct RefreshCommitCoin *commit_coin);
 
 
 int
@@ -148,12 +174,6 @@ TALER_MINT_DB_get_refresh_commit_coin (PGconn *db_conn,
                                        struct RefreshCommitCoin *commit_coin);
 
 
-int
-TALER_MINT_DB_create_refresh_session (PGconn *db_conn,
-                                      const struct GNUNET_CRYPTO_EddsaPublicKey
-                                      *session_pub);
-
-
 struct GNUNET_CRYPTO_rsa_PublicKey *
 TALER_MINT_DB_get_refresh_order (PGconn *db_conn,
                                  uint16_t newcoin_index,
@@ -178,6 +198,7 @@ int
 TALER_MINT_DB_set_reveal_ok (PGconn *db_conn,
                              const struct GNUNET_CRYPTO_EddsaPublicKey *session_pub);
 
+
 int
 TALER_MINT_DB_insert_refresh_melt (PGconn *db_conn,
                                     const struct GNUNET_CRYPTO_EddsaPublicKey *session_pub,
@@ -193,11 +214,15 @@ TALER_MINT_DB_get_refresh_melt (PGconn *db_conn,
                                 struct GNUNET_CRYPTO_EcdsaPublicKey *coin_pub);
 
 
-typedef
-int (*LinkIterator) (void *cls,
-                     const struct LinkDataEnc *link_data_enc,
-                     const struct GNUNET_CRYPTO_rsa_PublicKey *denom_pub,
-                     const struct GNUNET_CRYPTO_rsa_Signature *ev_sig);
+/**
+ * FIXME: doc, name is bad, too.
+ */
+typedef int
+(*LinkIterator) (void *cls,
+                 const struct TALER_RefreshLinkEncrypted *link_data_enc,
+                 const struct GNUNET_CRYPTO_rsa_PublicKey *denom_pub,
+                 const struct GNUNET_CRYPTO_rsa_Signature *ev_sig);
+
 
 int
 TALER_db_get_link (PGconn *db_conn,
@@ -206,26 +231,37 @@ TALER_db_get_link (PGconn *db_conn,
                    void *cls);
 
 
+/**
+ * Obtain shared secret from the transfer public key (?).
+ *
+ * @param shared_secret_enc[out] set to shared secret; FIXME: use other type
+ *               to indicate this is the encrypted secret
+ */
 int
 TALER_db_get_transfer (PGconn *db_conn,
                        const struct GNUNET_CRYPTO_EcdsaPublicKey *coin_pub,
                        struct GNUNET_CRYPTO_EcdsaPublicKey *transfer_pub,
-                       struct SharedSecretEnc *shared_secret_enc);
+                       struct GNUNET_HashCode *shared_secret_enc);
 
 int
 TALER_MINT_DB_init_deposits (PGconn *db_conn, int temporary);
 
+
 int
 TALER_MINT_DB_prepare_deposits (PGconn *db_conn);
 
+
 int
 TALER_MINT_DB_insert_deposit (PGconn *db_conn,
                               const struct Deposit *deposit);
 
+
 int
 TALER_MINT_DB_get_deposit (PGconn *db_conn,
                            const struct GNUNET_CRYPTO_EddsaPublicKey *coin_pub,
                            struct Deposit **r_deposit);
+
+
 int
 TALER_MINT_DB_insert_known_coin (PGconn *db_conn,
                                  const struct KnownCoin *known_coin);
diff --git a/src/mint/taler-mint-httpd_db.c b/src/mint/taler-mint-httpd_db.c
index 59e573457..874ac72ee 100644
--- a/src/mint/taler-mint-httpd_db.c
+++ b/src/mint/taler-mint-httpd_db.c
@@ -689,8 +689,10 @@ TALER_MINT_db_execute_refresh_melt (struct MHD_Connection *connection,
  *
  * @param connection the MHD connection to handle
  * @param kappa size of x-dimension of @commit_coin and @commit_link arrays
- * @param num_oldcoins size of y-dimension of @commit_coin and @commit_link arrays
- * @param num_newcoins size of y-dimension of @commit_coin and @commit_link arrays
+ * @param num_oldcoins size of y-dimension of @commit_link array
+ * @param num_newcoins size of y-dimension of @commit_coin array
+ * @param commit_coin
+ * @param commit_link
  * @return MHD result code
  */
 int
@@ -730,6 +732,9 @@ TALER_MINT_db_execute_refresh_commit (struct MHD_Connection *connection,
     {
       if (GNUNET_OK !=
           TALER_MINT_DB_insert_refresh_commit_coin (db_conn,
+                                                    refresh_session_pub,
+                                                    i,
+                                                    j,
                                                     &commit_coin[i][j]))
       {
         // FIXME: return 'internal error'?
@@ -739,7 +744,11 @@ TALER_MINT_db_execute_refresh_commit (struct MHD_Connection *connection,
       }
 
       if (GNUNET_OK !=
-          TALER_MINT_DB_insert_refresh_commit_link (db_conn, &commit_link[i][j]))
+          TALER_MINT_DB_insert_refresh_commit_link (db_conn,
+                                                    refresh_session_pub,
+                                                    i,
+                                                    j,
+                                                    &commit_link[i][j]))
       {
         // FIXME: return 'internal error'?
         GNUNET_break (0);
diff --git a/src/mint/taler-mint-httpd_db.h b/src/mint/taler-mint-httpd_db.h
index 31f64d9f7..3f8c13414 100644
--- a/src/mint/taler-mint-httpd_db.h
+++ b/src/mint/taler-mint-httpd_db.h
@@ -103,8 +103,10 @@ TALER_MINT_db_execute_refresh_melt (struct MHD_Connection *connection,
  *
  * @param connection the MHD connection to handle
  * @param kappa size of x-dimension of @commit_coin and @commit_link arrays
- * @param num_oldcoins size of y-dimension of @commit_coin and @commit_link arrays
- * @param num_newcoins size of y-dimension of @commit_coin and @commit_link arrays
+ * @param num_oldcoins size of y-dimension of @commit_coin array
+ * @param num_newcoins size of y-dimension of @commit_link array
+ * @param commit_coin
+ * @param commit_link
  * @return MHD result code
  */
 int
diff --git a/src/mint/taler-mint-httpd_refresh.c b/src/mint/taler-mint-httpd_refresh.c
index 40737ae31..42a224f32 100644
--- a/src/mint/taler-mint-httpd_refresh.c
+++ b/src/mint/taler-mint-httpd_refresh.c
@@ -541,6 +541,9 @@ TALER_MINT_handler_refresh_commit (struct RequestHandler *rh,
                                     sizeof (struct RefreshCommitCoin));
     for (j = 0; j < num_newcoins; j++)
     {
+      char *link_end;
+      size_t link_enc_size;
+
       res = GNUNET_MINT_parse_navigate_json (connection, root,
                                              JNAV_FIELD, "coin_evs",
                                              JNAV_INDEX, (int) i,
@@ -565,9 +568,9 @@ TALER_MINT_handler_refresh_commit (struct RequestHandler *rh,
                                              JNAV_FIELD, "link_encs",
                                              JNAV_INDEX, (int) i,
                                              JNAV_INDEX, (int) j,
-                                             JNAV_RET_DATA,
-                                             commit_coin[i][j].link_enc,
-                                             TALER_REFRESH_LINK_LENGTH);
+                                             JNAV_RET_DATA_VAR,
+                                             &link_enc,
+                                             &link_enc_size);
       if (GNUNET_OK != res)
       {
         // FIXME: return 'internal error'?
@@ -575,13 +578,13 @@ TALER_MINT_handler_refresh_commit (struct RequestHandler *rh,
         GNUNET_CRYPTO_hash_context_abort (hash_context);
         return (GNUNET_SYSERR == res) ? MHD_NO : MHD_YES;
       }
+      // FIXME: convert link_enc / link_enc_size to
+      // commit_coin[i][j].refresh_link!
+
 
       GNUNET_CRYPTO_hash_context_read (hash_context,
                                        commit_coin[i][j].link_enc,
                                        TALER_REFRESH_LINK_LENGTH);
-      commit_coin[i][j].cnc_index = i;
-      commit_coin[i][j].newcoin_index = j;
-      commit_coin[i][j].session_pub = refresh_session_pub;
     }
   }
 
@@ -617,8 +620,8 @@ TALER_MINT_handler_refresh_commit (struct RequestHandler *rh,
                                              JNAV_INDEX, (int) i,
                                              JNAV_INDEX, (int) j,
                                              JNAV_RET_DATA,
-                                             commit_link[i][j].shared_secret_enc,
-                                             TALER_REFRESH_SHARED_SECRET_LENGTH);
+                                             &commit_link[i][j].shared_secret,
+                                             sizeof (struct GNUNET_HashCode));
 
       if (GNUNET_OK != res)
       {
@@ -628,13 +631,8 @@ TALER_MINT_handler_refresh_commit (struct RequestHandler *rh,
       }
 
       GNUNET_CRYPTO_hash_context_read (hash_context,
-                                       commit_link[i][j].shared_secret_enc,
-                                       TALER_REFRESH_SHARED_SECRET_LENGTH);
-
-      commit_link[i][j].cnc_index = i;
-      commit_link[i][j].oldcoin_index = j;
-      commit_link[i][j].session_pub = refresh_session_pub;
-
+                                       &commit_link[i][j].shared_secret,
+                                       sizeof (struct GNUNET_HashCode));
     }
   }
   GNUNET_CRYPTO_hash_context_finish (hash_context, &commit_hash);
diff --git a/src/mint/taler-mint-keyup.c b/src/mint/taler-mint-keyup.c
index a57b1e6ba..7c35317ce 100644
--- a/src/mint/taler-mint-keyup.c
+++ b/src/mint/taler-mint-keyup.c
@@ -646,9 +646,10 @@ main (int argc, char *const *argv)
   // check if key from file matches the one from the configuration
   {
     struct GNUNET_CRYPTO_EddsaPublicKey master_pub_from_cfg;
-    if (GNUNET_OK != TALER_configuration_get_data (kcfg, "mint", "master_pub",
-                                                   &master_pub_from_cfg,
-                                                   sizeof (struct GNUNET_CRYPTO_EddsaPublicKey)))
+    if (GNUNET_OK !=
+        GNUNET_CONFIGURATION_get_data (kcfg, "mint", "master_pub",
+                                       &master_pub_from_cfg,
+                                       sizeof (struct GNUNET_CRYPTO_EddsaPublicKey)))
     {
       fprintf (stderr, "master key missing in configuration (mint.master_pub)\n");
       return 1;