major rework of the KYC logic, making it more configurable, not complete, but tests pass again

1 files changed, 101 insertions, 18 deletions

diff --git a/src/exchange/taler-exchange-httpd_kyc-wallet.c b/src/exchange/taler-exchange-httpd_kyc-wallet.c
index 0d92efd3..a043de6f 100644
--- a/src/exchange/taler-exchange-httpd_kyc-wallet.c
+++ b/src/exchange/taler-exchange-httpd_kyc-wallet.c
@@ -1,6 +1,6 @@
 /*
   This file is part of TALER
-  Copyright (C) 2021 Taler Systems SA
+  Copyright (C) 2021, 2022 Taler Systems SA
 
   TALER is free software; you can redistribute it and/or modify it under the
   terms of the GNU Affero General Public License as published by the Free Software
@@ -26,6 +26,7 @@
 #include <pthread.h>
 #include "taler_json_lib.h"
 #include "taler_mhd_lib.h"
+#include "taler_kyclogic_lib.h"
 #include "taler-exchange-httpd_kyc-wallet.h"
 #include "taler-exchange-httpd_responses.h"
 
@@ -38,16 +39,55 @@ struct KycRequestContext
   /**
    * Public key of the reserve/wallet this is about.
    */
-  struct TALER_ReservePublicKeyP reserve_pub;
+  struct TALER_PaytoHashP h_payto;
 
   /**
-   * Current KYC status.
+   * Row with the legitimization requirement.
    */
-  struct TALER_EXCHANGEDB_KycStatus kyc;
+  uint64_t legi_row;
+
+  /**
+   * Balance threshold crossed by the wallet.
+   */
+  struct TALER_Amount balance;
+
+  /**
+   * Name of the required check.
+   */
+  const char *required;
+
 };
 
 
 /**
+ * Function called to iterate over KYC-relevant
+ * transaction amounts for a particular time range.
+ * Returns the wallet balance.
+ *
+ * @param cls closure, a `struct KycRequestContext`
+ * @param limit maximum time-range for which events
+ *        should be fetched (timestamp in the past)
+ * @param cb function to call on each event found,
+ *        events must be returned in reverse chronological
+ *        order
+ * @param cb_cls closure for @a cb
+ */
+static void
+balance_iterator (void *cls,
+                  struct GNUNET_TIME_Absolute limit,
+                  TALER_EXCHANGEDB_KycAmountCallback cb,
+                  void *cb_cls)
+{
+  struct KycRequestContext *krc = cls;
+
+  (void) limit;
+  cb (cb_cls,
+      &krc->balance,
+      GNUNET_TIME_absolute_get ());
+}
+
+
+/**
  * Function implementing database transaction to check wallet's KYC status.
  * Runs the transaction logic; IF it returns a non-error code, the transaction
  * logic MUST NOT queue a MHD response.  IF it returns an hard error, the
@@ -69,9 +109,23 @@ wallet_kyc_check (void *cls,
   struct KycRequestContext *krc = cls;
   enum GNUNET_DB_QueryStatus qs;
 
-  qs = TEH_plugin->inselect_wallet_kyc_status (TEH_plugin->cls,
-                                               &krc->reserve_pub,
-                                               &krc->kyc);
+  krc->required = TALER_KYCLOGIC_kyc_test_required (
+    TALER_KYCLOGIC_KYC_TRIGGER_WALLET_BALANCE,
+    &krc->h_payto,
+    TEH_plugin->select_satisfied_kyc_processes,
+    TEH_plugin->cls,
+    &balance_iterator,
+    krc);
+  GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+              "KYC check required at %s is `%s'\n",
+              TALER_amount2s (&krc->balance),
+              krc->required);
+  if (NULL == krc->required)
+    return GNUNET_DB_STATUS_SUCCESS_NO_RESULTS;
+  qs = TEH_plugin->insert_kyc_requirement_for_account (TEH_plugin->cls,
+                                                       krc->required,
+                                                       &krc->h_payto,
+                                                       &krc->legi_row);
   if (qs < 0)
   {
     if (GNUNET_DB_STATUS_SOFT_ERROR == qs)
@@ -80,9 +134,14 @@ wallet_kyc_check (void *cls,
     *mhd_ret = TALER_MHD_reply_with_error (connection,
                                            MHD_HTTP_INTERNAL_SERVER_ERROR,
                                            TALER_EC_GENERIC_DB_FETCH_FAILED,
-                                           "inselect_wallet_status");
+                                           "insert_kyc_requirement_for_account");
     return qs;
   }
+  GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+              "KYC requirement inserted for wallet %s (%llu, %d)\n",
+              TALER_B2S (&krc->h_payto),
+              (unsigned long long) krc->legi_row,
+              qs);
   return qs;
 }
 
@@ -95,11 +154,17 @@ TEH_handler_kyc_wallet (
 {
   struct TALER_ReserveSignatureP reserve_sig;
   struct KycRequestContext krc;
+  struct TALER_ReservePublicKeyP reserve_pub;
   struct GNUNET_JSON_Specification spec[] = {
     GNUNET_JSON_spec_fixed_auto ("reserve_sig",
                                  &reserve_sig),
     GNUNET_JSON_spec_fixed_auto ("reserve_pub",
-                                 &krc.reserve_pub),
+                                 &reserve_pub),
+    // FIXME: add balance threshold crossed to the request
+    // to spec and client API!
+    TALER_JSON_spec_amount ("balance",
+                            TEH_currency,
+                            &krc.balance),
     GNUNET_JSON_spec_end ()
   };
   MHD_RESULT res;
@@ -115,8 +180,10 @@ TEH_handler_kyc_wallet (
     return MHD_YES;   /* failure */
 
   TEH_METRICS_num_verifications[TEH_MT_SIGNATURE_EDDSA]++;
+  // FIXME: add balance threshold crossed to
+  // what the wallet signs over!
   if (GNUNET_OK !=
-      TALER_wallet_account_setup_verify (&krc.reserve_pub,
+      TALER_wallet_account_setup_verify (&reserve_pub,
                                          &reserve_sig))
   {
     GNUNET_break_op (0);
@@ -126,13 +193,19 @@ TEH_handler_kyc_wallet (
       TALER_EC_EXCHANGE_KYC_WALLET_SIGNATURE_INVALID,
       NULL);
   }
-  if (TEH_KYC_NONE == TEH_kyc_config.mode)
-    return TALER_MHD_reply_static (
-      rc->connection,
-      MHD_HTTP_NO_CONTENT,
-      NULL,
-      NULL,
-      0);
+  {
+    char *payto_uri;
+
+    payto_uri = TALER_reserve_make_payto (TEH_base_url,
+                                          &reserve_pub);
+    TALER_payto_hash (payto_uri,
+                      &krc.h_payto);
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                "h_payto of wallet %s is %s\n",
+                payto_uri,
+                TALER_B2S (&krc.h_payto));
+    GNUNET_free (payto_uri);
+  }
   ret = TEH_DB_run_transaction (rc->connection,
                                 "check wallet kyc",
                                 TEH_MT_REQUEST_OTHER,
@@ -141,11 +214,21 @@ TEH_handler_kyc_wallet (
                                 &krc);
   if (GNUNET_SYSERR == ret)
     return res;
+  if (NULL == krc.required)
+  {
+    /* KYC not required or already satisfied */
+    return TALER_MHD_reply_static (
+      rc->connection,
+      MHD_HTTP_NO_CONTENT,
+      NULL,
+      NULL,
+      0);
+  }
   return TALER_MHD_REPLY_JSON_PACK (
     rc->connection,
     MHD_HTTP_OK,
     GNUNET_JSON_pack_uint64 ("payment_target_uuid",
-                             krc.kyc.payment_target_uuid));
+                             krc.legi_row));
 }