towards KYC AML triggers

src/exchange/Makefile.am

@@ -131,6 +131,7 @@ taler_exchange_httpd_SOURCES = \
   taler-exchange-httpd_age-withdraw.c taler-exchange-httpd_age-withdraw.h \
   taler-exchange-httpd_age-withdraw_reveal.c taler-exchange-httpd_age-withdraw_reveal.h \
   taler-exchange-httpd_common_deposit.c taler-exchange-httpd_common_deposit.h \
+  taler-exchange-httpd_common_kyc.c taler-exchange-httpd_common_kyc.h \
   taler-exchange-httpd_config.c taler-exchange-httpd_config.h \
   taler-exchange-httpd_contract.c taler-exchange-httpd_contract.h \
   taler-exchange-httpd_csr.c taler-exchange-httpd_csr.h \

src/exchange/taler-exchange-httpd_common_kyc.c

@@ -0,0 +1,259 @@
+/*
+  This file is part of TALER
+  Copyright (C) 2023 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
+  Foundation; either version 3, or (at your option) any later version.
+
+  TALER is distributed in the hope that it will be useful, but WITHOUT ANY
+  WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+  A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more details.
+
+  You should have received a copy of the GNU Affero General Public License along with
+  TALER; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
+*/
+/**
+ * @file taler-exchange-httpd_common_kyc.c
+ * @brief shared logic for finishing a KYC process
+ * @author Christian Grothoff
+ */
+#include "platform.h"
+#include "taler-exchange-httpd_common_kyc.h"
+#include "taler_attributes.h"
+#include "taler_exchangedb_plugin.h"
+
+struct TEH_KycAmlTrigger
+{
+
+  /**
+   * Our logging scope.
+   */
+  struct GNUNET_AsyncScopeId scope;
+
+  /**
+   * account the operation is about
+   */
+  struct TALER_PaytoHashP account_id;
+
+  /**
+   * until when is the KYC data valid
+   */
+  struct GNUNET_TIME_Absolute expiration;
+
+  /**
+   * legitimization process the KYC data is about
+   */
+  uint64_t process_row;
+
+  /**
+   * name of the configuration section of the logic that was run
+   */
+  char *provider_section;
+
+  /**
+   * set to user ID at the provider, or NULL if not supported or unknown
+   */
+  char *provider_user_id;
+
+  /**
+   * provider_legitimization_id set to legitimization process ID at the provider, or NULL if not supported or unknown
+   */
+  char *provider_legitimization_id;
+
+  /**
+   * function to call with the result
+   */
+  TEH_KycAmlTriggerCallback cb;
+
+  /**
+   * closure for @e cb
+   */
+  void *cb_cls;
+
+  /**
+   * user attributes returned by the provider
+   */
+  json_t *attributes;
+
+  /**
+   * response to return to the HTTP client
+   */
+  struct MHD_Response *response;
+
+  /**
+   * Handle to an external process that evalutates the
+   * need to run AML on the account.
+   */
+  struct TALER_JSON_ExternalConversion *kyc_aml;
+
+  /**
+   * HTTP status code of @e response
+   */
+  unsigned int http_status;
+
+};
+
+
+/**
+ * Type of a callback that receives a JSON @a result.
+ *
+ * @param cls closure of type `struct TEH_KycAmlTrigger *`
+ * @param status_type how did the process die
+ * @param code termination status code from the process
+ * @param result some JSON result, NULL if we failed to get an JSON output
+ */
+static void
+kyc_aml_finished (void *cls,
+                  enum GNUNET_OS_ProcessStatusType status_type,
+                  unsigned long code,
+                  const json_t *result)
+{
+  struct TEH_KycAmlTrigger *kat = cls;
+  enum GNUNET_DB_QueryStatus qs;
+  size_t eas;
+  void *ea;
+  const char *birthdate;
+  struct GNUNET_ShortHashCode kyc_prox;
+  struct GNUNET_AsyncScopeSave old_scope;
+
+  kat->kyc_aml = NULL;
+  GNUNET_async_scope_enter (&kat->scope,
+                            &old_scope);
+  TALER_CRYPTO_attributes_to_kyc_prox (kat->attributes,
+                                       &kyc_prox);
+  birthdate = json_string_value (json_object_get (kat->attributes,
+                                                  TALER_ATTRIBUTE_BIRTHDATE));
+  TALER_CRYPTO_kyc_attributes_encrypt (&TEH_attribute_key,
+                                       kat->attributes,
+                                       &ea,
+                                       &eas);
+  // FIXME: begin transaction (or move everything into one stored procedure?)
+  qs = TEH_plugin->insert_kyc_attributes (
+    TEH_plugin->cls,
+    &kat->account_id,
+    &kyc_prox,
+    kat->provider_section,
+    birthdate,
+    GNUNET_TIME_timestamp_get (),
+    GNUNET_TIME_absolute_to_timestamp (kat->expiration),
+    eas,
+    ea);
+  GNUNET_free (ea);
+  if (GNUNET_DB_STATUS_HARD_ERROR == qs)
+  {
+    GNUNET_break (0);
+    if (NULL != kat->response)
+      MHD_destroy_response (kat->response);
+    kat->http_status = MHD_HTTP_INTERNAL_SERVER_ERROR;
+    kat->response = TALER_MHD_make_error (TALER_EC_GENERIC_DB_STORE_FAILED,
+                                          "insert_kyc_attributes");
+    goto finish;
+  }
+  qs = TEH_plugin->update_kyc_process_by_row (TEH_plugin->cls,
+                                              kat->process_row,
+                                              kat->provider_section,
+                                              &kat->account_id,
+                                              kat->provider_user_id,
+                                              kat->provider_legitimization_id,
+                                              kat->expiration);
+  if (GNUNET_DB_STATUS_HARD_ERROR == qs)
+  {
+    GNUNET_break (0);
+    if (NULL != kat->response)
+      MHD_destroy_response (kat->response);
+    kat->http_status = MHD_HTTP_INTERNAL_SERVER_ERROR;
+    kat->response = TALER_MHD_make_error (TALER_EC_GENERIC_DB_STORE_FAILED,
+                                          "update_kyc_process_by_row");
+    goto finish;
+  }
+  // FIXME: do DB work, possibly updating kat!
+  if (0 != code)
+  {
+    // FIXME: trigger AML!
+    GNUNET_break (0); // FIXME: not implemented
+  }
+  // FIXME: end transaction
+
+  /* Finally, return result to main handler */
+finish:
+  kat->cb (kat->cb_cls,
+           kat->http_status,
+           kat->response);
+  kat->response = NULL;
+  TEH_kyc_finished_cancel (kat);
+  GNUNET_async_scope_restore (&old_scope);
+}
+
+
+struct TEH_KycAmlTrigger *
+TEH_kyc_finished (const struct GNUNET_AsyncScopeId *scope,
+                  uint64_t process_row,
+                  const struct TALER_PaytoHashP *account_id,
+                  const char *provider_section,
+                  const char *provider_user_id,
+                  const char *provider_legitimization_id,
+                  struct GNUNET_TIME_Absolute expiration,
+                  const json_t *attributes,
+                  unsigned int http_status,
+                  struct MHD_Response *response,
+                  TEH_KycAmlTriggerCallback cb,
+                  void *cb_cls)
+{
+  struct TEH_KycAmlTrigger *kat;
+
+  kat = GNUNET_new (struct TEH_KycAmlTrigger);
+  kat->scope = *scope;
+  kat->process_row = process_row;
+  kat->account_id = *account_id;
+  kat->provider_section
+    = GNUNET_strdup (provider_section);
+  if (NULL != provider_user_id)
+    kat->provider_user_id
+      = GNUNET_strdup (provider_user_id);
+  if (NULL != provider_legitimization_id)
+    kat->provider_legitimization_id
+      = GNUNET_strdup (provider_legitimization_id);
+  kat->expiration = expiration;
+  kat->attributes = json_incref ((json_t*) attributes);
+  kat->http_status = http_status;
+  kat->response = response;
+  kat->cb = cb;
+  kat->cb_cls = cb_cls;
+  kat->kyc_aml
+    = TALER_JSON_external_conversion_start (
+        attributes,
+        &kyc_aml_finished,
+        kat,
+        TEH_kyc_aml_trigger,
+        TEH_kyc_aml_trigger,
+        NULL);
+  if (NULL == kat->kyc_aml)
+  {
+    GNUNET_break (0);
+    TEH_kyc_finished_cancel (kat);
+    return NULL;
+  }
+  return kat;
+}
+
+
+void
+TEH_kyc_finished_cancel (struct TEH_KycAmlTrigger *kat)
+{
+  if (NULL != kat->kyc_aml)
+  {
+    TALER_JSON_external_conversion_stop (kat->kyc_aml);
+    kat->kyc_aml = NULL;
+  }
+  GNUNET_free (kat->provider_section);
+  GNUNET_free (kat->provider_user_id);
+  GNUNET_free (kat->provider_legitimization_id);
+  json_decref (kat->attributes);
+  if (NULL != kat->response)
+  {
+    MHD_destroy_response (kat->response);
+    kat->response = NULL;
+  }
+  GNUNET_free (kat);
+}

src/exchange/taler-exchange-httpd_common_kyc.h

@@ -0,0 +1,100 @@
+/*
+  This file is part of TALER
+  Copyright (C) 2023 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
+  Foundation; either version 3, or (at your option) any later version.
+
+  TALER is distributed in the hope that it will be useful, but WITHOUT ANY
+  WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+  A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more details.
+
+  You should have received a copy of the GNU Affero General Public License along with
+  TALER; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
+*/
+/**
+ * @file taler-exchange-httpd_common_kyc.h
+ * @brief shared logic for finishing a KYC process
+ * @author Christian Grothoff
+ */
+#ifndef TALER_EXCHANGE_HTTPD_COMMON_KYC_H
+#define TALER_EXCHANGE_HTTPD_COMMON_KYC_H
+
+#include <gnunet/gnunet_util_lib.h>
+#include <gnunet/gnunet_json_lib.h>
+#include <jansson.h>
+#include <microhttpd.h>
+#include "taler_json_lib.h"
+#include "taler_mhd_lib.h"
+#include "taler-exchange-httpd.h"
+
+
+/**
+ * Function called after the KYC-AML trigger is done.
+ *
+ * @param cls closure
+ * @param http_status final HTTP status to return
+ * @param[in] response final HTTP ro return
+ */
+typedef void
+(*TEH_KycAmlTriggerCallback) (
+  void *cls,
+  unsigned int http_status,
+  struct MHD_Response *response);
+
+
+/**
+ * Handle for an asynchronous operation to finish
+ * a KYC process after running the AML trigger.
+ */
+struct TEH_KycAmlTrigger;
+
+// FIXME: also pass async log context and set it!
+/**
+ * We have finished a KYC process and obtained new
+ * @a attributes for a given @a account_id.
+ * Check with the KYC-AML trigger to see if we need
+ * to initiate an AML process, and store the attributes
+ * in the database. Then call @a cb.
+ *
+ * @param scope the HTTP request logging scope
+ * @param process_row legitimization process the webhook was about
+ * @param account_id account the webhook was about
+ * @param provider_section name of the configuration section of the logic that was run
+ * @param provider_user_id set to user ID at the provider, or NULL if not supported or unknown
+ * @param provider_legitimization_id set to legitimization process ID at the provider, or NULL if not supported or unknown
+ * @param status KYC status
+ * @param expiration until when is the KYC check valid
+ * @param attributes user attributes returned by the provider
+ * @param http_status HTTP status code of @a response
+ * @param[in] response to return to the HTTP client
+ * @param cb function to call with the result
+ * @param cb_cls closure for @a cb
+ * @return handle to cancel the operation
+ */
+struct TEH_KycAmlTrigger *
+TEH_kyc_finished (const struct GNUNET_AsyncScopeId *scope,
+                  uint64_t process_row,
+                  const struct TALER_PaytoHashP *account_id,
+                  const char *provider_section,
+                  const char *provider_user_id,
+                  const char *provider_legitimization_id,
+                  struct GNUNET_TIME_Absolute expiration,
+                  const json_t *attributes,
+                  unsigned int http_status,
+                  struct MHD_Response *response,
+                  TEH_KycAmlTriggerCallback cb,
+                  void *cb_cls);
+
+
+/**
+ * Cancel KYC finish operation.
+ *
+ * @param[in] kat operation to abort
+ */
+void
+TEH_kyc_finished_cancel (struct TEH_KycAmlTrigger *kat);
+
+
+#endif

src/exchange/taler-exchange-httpd_kyc-proof.c

@@ -1,6 +1,6 @@
 /*
   This file is part of TALER
-  Copyright (C) 2021-2022 Taler Systems SA
+  Copyright (C) 2021-2023 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
@@ -23,11 +23,11 @@
 #include <gnunet/gnunet_json_lib.h>
 #include <jansson.h>
 #include <microhttpd.h>
-#include <pthread.h>
 #include "taler_attributes.h"
 #include "taler_json_lib.h"
 #include "taler_kyclogic_lib.h"
 #include "taler_mhd_lib.h"
+#include "taler-exchange-httpd_common_kyc.h"
 #include "taler-exchange-httpd_kyc-proof.h"
 #include "taler-exchange-httpd_responses.h"
 
@@ -68,6 +68,11 @@ struct KycProofContext
    */
   struct TALER_KYCLOGIC_ProofHandle *ph;
 
+  /**
+   * KYC AML trigger operation.
+   */
+  struct TEH_KycAmlTrigger *kat;
+
   /**
    * Process information about the user for the plugin from the database, can
    * be NULL.
@@ -159,6 +164,28 @@ TEH_kyc_proof_cleanup (void)
 }
 
 
+/**
+ * Function called after the KYC-AML trigger is done.
+ *
+ * @param cls closure
+ * @param http_status final HTTP status to return
+ * @param[in] response final HTTP ro return
+ */
+static void
+proof_finish (
+  void *cls,
+  unsigned int http_status,
+  struct MHD_Response *response)
+{
+  struct KycProofContext *kpc = cls;
+
+  kpc->kat = NULL;
+  kpc->response_code = http_status;
+  kpc->response = response;
+  kpc_resume (kpc);
+}
+
+
 /**
  * Function called with the result of a proof check operation.
  *
@@ -192,74 +219,40 @@ proof_cb (
   kpc->ph = NULL;
   GNUNET_async_scope_enter (&rc->async_scope_id,
                             &old_scope);
-
   if (TALER_KYCLOGIC_STATUS_SUCCESS == status)
   {
-    enum GNUNET_DB_QueryStatus qs;
+    kpc->kat = TEH_kyc_finished (&rc->async_scope_id,
-    size_t eas;
-    void *ea;
-    const char *birthdate;
-    struct GNUNET_ShortHashCode kyc_prox;
-
-    TALER_CRYPTO_attributes_to_kyc_prox (attributes,
-                                         &kyc_prox);
-    birthdate = json_string_value (json_object_get (attributes,
-                                                    TALER_ATTRIBUTE_BIRTHDATE));
-    TALER_CRYPTO_kyc_attributes_encrypt (&TEH_attribute_key,
-                                         attributes,
-                                         &ea,
-                                         &eas);
-    qs = TEH_plugin->insert_kyc_attributes (
-      TEH_plugin->cls,
-      &kpc->h_payto,
-      &kyc_prox,
-      kpc->provider_section,
-      birthdate,
-      GNUNET_TIME_timestamp_get (),
-      GNUNET_TIME_absolute_to_timestamp (expiration),
-      eas,
-      ea);
-    GNUNET_free (ea);
-    if (GNUNET_DB_STATUS_HARD_ERROR == qs)
-    {
-      GNUNET_break (0);
-      if (NULL != response)
-        MHD_destroy_response (response);
-      kpc->response_code = MHD_HTTP_INTERNAL_SERVER_ERROR;
-      kpc->response = TALER_MHD_make_error (TALER_EC_GENERIC_DB_STORE_FAILED,
-                                            "insert_kyc_attributes");
-      GNUNET_async_scope_restore (&old_scope);
-      return;
-    }
-    qs = TEH_plugin->update_kyc_process_by_row (TEH_plugin->cls,
                                  kpc->process_row,
-                                                kpc->provider_section,
                                  &kpc->h_payto,
+                                 kpc->provider_section,
                                  provider_user_id,
                                  provider_legitimization_id,
-                                                expiration);
+                                 expiration,
-    if (GNUNET_DB_STATUS_HARD_ERROR == qs)
+                                 attributes,
+                                 http_status,
+                                 response,
+                                 &proof_finish,
+                                 kpc);
+    if (NULL == kpc->kat)
     {
-      GNUNET_break (0);
+      http_status = MHD_HTTP_INTERNAL_SERVER_ERROR;
       if (NULL != response)
         MHD_destroy_response (response);
-      kpc->response_code = MHD_HTTP_INTERNAL_SERVER_ERROR;
+      response = TALER_MHD_make_error (
-      kpc->response = TALER_MHD_make_error (TALER_EC_GENERIC_DB_STORE_FAILED,
+        TALER_EC_EXCHANGE_GENERIC_BAD_CONFIGURATION,
-                                            "set_kyc_ok");
+        "[exchange] AML_KYC_TRIGGER");
-      GNUNET_async_scope_restore (&old_scope);
-      return;
     }
   }
-  else
+  if (NULL == kpc->kat)
   {
     GNUNET_log (GNUNET_ERROR_TYPE_INFO,
                 "KYC process #%llu failed with status %d\n",
                 (unsigned long long) kpc->process_row,
                 status);
+    proof_finish (kpc,
+                  http_status,
+                  response);
   }
-  kpc->response_code = http_status;
-  kpc->response = response;
-  kpc_resume (kpc);
   GNUNET_async_scope_restore (&old_scope);
 }
 
@@ -279,6 +272,11 @@ clean_kpc (struct TEH_RequestContext *rc)
     kpc->logic->proof_cancel (kpc->ph);
     kpc->ph = NULL;
   }
+  if (NULL != kpc->kat)
+  {
+    TEH_kyc_finished_cancel (kpc->kat);
+    kpc->kat = NULL;
+  }
   if (NULL != kpc->response)
   {
     MHD_destroy_response (kpc->response);

src/exchange/taler-exchange-httpd_kyc-webhook.c

@@ -1,6 +1,6 @@
 /*
   This file is part of TALER
-  Copyright (C) 2022 Taler Systems SA
+  Copyright (C) 2022-2023 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
@@ -28,6 +28,7 @@
 #include "taler_json_lib.h"
 #include "taler_mhd_lib.h"
 #include "taler_kyclogic_lib.h"
+#include "taler-exchange-httpd_common_kyc.h"
 #include "taler-exchange-httpd_kyc-webhook.h"
 #include "taler-exchange-httpd_responses.h"
 
@@ -53,6 +54,11 @@ struct KycWebhookContext
    */
   struct TEH_RequestContext *rc;
 
+  /**
+   * Handle for the KYC-AML trigger interaction.
+   */
+  struct TEH_KycAmlTrigger *kat;
+
   /**
    * Plugin responsible for the webhook.
    */
@@ -140,6 +146,28 @@ TEH_kyc_webhook_cleanup (void)
 }
 
 
+/**
+ * Function called after the KYC-AML trigger is done.
+ *
+ * @param cls closure with a `struct KycWebhookContext *`
+ * @param http_status final HTTP status to return
+ * @param[in] response final HTTP ro return
+ */
+static void
+kyc_aml_webhook_finished (
+  void *cls,
+  unsigned int http_status,
+  struct MHD_Response *response)
+{
+  struct KycWebhookContext *kwh = cls;
+
+  kwh->kat = NULL;
+  kwh->response = response;
+  kwh->response_code = http_status;
+  kwh_resume (kwh);
+}
+
+
 /**
  * Function called with the result of a KYC webhook operation.
  *
@@ -178,58 +206,27 @@ webhook_finished_cb (
   switch (status)
   {
   case TALER_KYCLOGIC_STATUS_SUCCESS:
-    /* _successfully_ resumed case */
+    kwh->kat = TEH_kyc_finished (
-    {
+      &kwh->rc->async_scope_id,
-      enum GNUNET_DB_QueryStatus qs;
-      size_t eas;
-      void *ea;
-      const char *birthdate;
-      struct GNUNET_ShortHashCode kyc_prox;
-
-      TALER_CRYPTO_attributes_to_kyc_prox (attributes,
-                                           &kyc_prox);
-      birthdate = json_string_value (json_object_get (attributes,
-                                                      TALER_ATTRIBUTE_BIRTHDATE));
-      TALER_CRYPTO_kyc_attributes_encrypt (&TEH_attribute_key,
-                                           attributes,
-                                           &ea,
-                                           &eas);
-      qs = TEH_plugin->insert_kyc_attributes (
-        TEH_plugin->cls,
-        account_id,
-        &kyc_prox,
-        provider_section,
-        birthdate,
-        GNUNET_TIME_timestamp_get (),
-        GNUNET_TIME_absolute_to_timestamp (expiration),
-        eas,
-        ea);
-      GNUNET_free (ea);
-      if (qs < 0)
-      {
-        GNUNET_break (0);
-        kwh->response = TALER_MHD_make_error (TALER_EC_GENERIC_DB_STORE_FAILED,
-                                              "insert_kyc_attributes");
-        kwh->response_code = MHD_HTTP_INTERNAL_SERVER_ERROR;
-        kwh_resume (kwh);
-        return;
-      }
-      qs = TEH_plugin->update_kyc_process_by_row (TEH_plugin->cls,
       process_row,
-                                                  provider_section,
       account_id,
+      provider_section,
       provider_user_id,
       provider_legitimization_id,
-                                                  expiration);
+      expiration,
-      if (qs < 0)
+      attributes,
+      http_status,
+      response,
+      &kyc_aml_webhook_finished,
+      kwh);
+    if (NULL == kwh->kat)
     {
-        GNUNET_break (0);
+      http_status = MHD_HTTP_INTERNAL_SERVER_ERROR;
-        kwh->response = TALER_MHD_make_error (TALER_EC_GENERIC_DB_STORE_FAILED,
+      if (NULL != response)
-                                              "set_kyc_ok");
+        MHD_destroy_response (response);
-        kwh->response_code = MHD_HTTP_INTERNAL_SERVER_ERROR;
+      response = TALER_MHD_make_error (
-        kwh_resume (kwh);
+        TALER_EC_EXCHANGE_GENERIC_BAD_CONFIGURATION,
-        return;
+        "[exchange] AML_KYC_TRIGGER");
-      }
     }
     break;
   default:
@@ -241,9 +238,10 @@ webhook_finished_cb (
                 status);
     break;
   }
-  kwh->response = response;
+  if (NULL == kwh->kat)
-  kwh->response_code = http_status;
+    kyc_aml_webhook_finished (kwh,
-  kwh_resume (kwh);
+                              http_status,
+                              response);
 }
 
 
@@ -262,6 +260,11 @@ clean_kwh (struct TEH_RequestContext *rc)
     kwh->plugin->webhook_cancel (kwh->wh);
     kwh->wh = NULL;
   }
+  if (NULL != kwh->kat)
+  {
+    TEH_kyc_finished_cancel (kwh->kat);
+    kwh->kat = NULL;
+  }
   if (NULL != kwh->response)
   {
     MHD_destroy_response (kwh->response);

src/exchangedb/pg_update_kyc_process_by_row.c

@@ -68,7 +68,8 @@ TEH_PG_update_kyc_process_by_row (
   if (qs <= 0)
   {
     GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
-                "Failed to update legitimization process: %d\n",
+                "Failed to update legitimization process %llu: %d\n",
+                (unsigned long long) process_row,
                 qs);
     return qs;
   }