merchant

commit 229d3a0aba2dd48000e46765037d87490078c549
parent ddbe83488339297e5c887c277ea2e28782cd5597
Author: Christian Grothoff <grothoff@gnunet.org>
Date:   Thu, 14 Aug 2025 11:11:43 +0200

fix output token signing offset computations

Diffstat:
M
src/backend/taler-merchant-httpd_post-orders-ID-pay.c
 | 
58
++++++++++++++++++++++++++++++++++++++++------------------

1 file changed, 40 insertions(+), 18 deletions(-)
diff --git a/src/backend/taler-merchant-httpd_post-orders-ID-pay.c b/src/backend/taler-merchant-httpd_post-orders-ID-pay.c
@@ -3087,12 +3087,13 @@ test_tfk_mandatory (enum TALER_MERCHANTDB_TokenFamilyKind tfk)
  *         #GNUNET_OK on success
  */
 static enum GNUNET_GenericReturnValue
-sign_token_envelopes (struct PayContext *pc,
-                      struct TALER_MERCHANT_ContractTokenFamilyKey *key,
-                      struct TALER_TokenIssuePrivateKey *priv,
-                      bool mandatory,
-                      unsigned int index,
-                      unsigned int expected_num)
+sign_token_envelopes (
+  struct PayContext *pc,
+  const struct TALER_MERCHANT_ContractTokenFamilyKey *key,
+  const struct TALER_TokenIssuePrivateKey *priv,
+  bool mandatory,
+  unsigned int index,
+  unsigned int expected_num)
 {
   unsigned int num_signed = 0;
 
@@ -3128,11 +3129,13 @@ sign_token_envelopes (struct PayContext *pc,
     TALER_token_issue_sign (priv,
                             &env->blinded_token,
                             &output->sig);
-    output->h_issue.hash = key->pub.public_key->pub_key_hash;
+    output->h_issue.hash
+      = key->pub.public_key->pub_key_hash;
     num_signed++;
   }
 
-  if (num_signed != expected_num)
+  if (mandatory &&
+      (num_signed != expected_num) )
   {
     GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
                 "Expected %d token envelopes for public key with valid_after "
@@ -3208,8 +3211,9 @@ handle_output_token (struct PayContext *pc,
   enum GNUNET_DB_QueryStatus qs;
   bool mandatory;
 
-  /* Locate token family in the contract.  This should never fail if
-   * the contract passed validation before insertion. */
+  /* Locate token family in the contract.
+     This should ever fail as this invariant should
+     have been checked when the contract was created. */
   family = find_family (pc,
                         output->details.token.token_family_slug);
   if (NULL == family)
@@ -3444,6 +3448,9 @@ phase_validate_tokens (struct PayContext *pc)
       const struct TALER_MERCHANT_ContractChoice *selected
         = &pc->check_contract.contract_terms->details.v1.choices[
             pc->parse_wallet_data.choice_index];
+      unsigned int output_off;
+      unsigned int cnt;
+      bool donau_seen = false;
 
       pc->validate_tokens.max_fee = selected->max_fee;
       pc->validate_tokens.brutto = selected->amount;
@@ -3505,6 +3512,7 @@ phase_validate_tokens (struct PayContext *pc)
       }
 
       /* calculate pc->output_tokens_len */
+      output_off = 0;
       for (unsigned int i = 0; i<selected->outputs_len; i++)
       {
         const struct TALER_MERCHANT_ContractOutput *output
@@ -3516,25 +3524,34 @@ phase_validate_tokens (struct PayContext *pc)
           GNUNET_assert (0);
           break;
         case TALER_MERCHANT_CONTRACT_OUTPUT_TYPE_TOKEN:
+          cnt = output->details.token.count;
           // FIXME: replace assert by returning 400
-          GNUNET_assert (pc->output_tokens_len + output->details.token.count
-                         >= pc->output_tokens_len);
-          pc->output_tokens_len += output->details.token.count;
+          GNUNET_assert (output_off + cnt
+                         >= output_off);
+          output_off += cnt;
           break;
         case TALER_MERCHANT_CONTRACT_OUTPUT_TYPE_DONATION_RECEIPT:
+          /* check that this output type appears at most once */
+          if (donau_seen)
+          {
+            // FIXME: return 400, duplicate donau
+          }
+          donau_seen = true;
           // FIXME: replace assert by returning 400
-          // FIXME: also check that this output type only appears ONCE
-          GNUNET_assert (pc->output_tokens_len + pc->parse_wallet_data.num_bkps
-                         >= pc->output_tokens_len);
-          pc->output_tokens_len += pc->parse_wallet_data.num_bkps;
+          GNUNET_assert (output_off + pc->parse_wallet_data.num_bkps
+                         >= output_off);
+          output_off += pc->parse_wallet_data.num_bkps;
           break;
         }
       }
 
+      pc->output_tokens_len = output_off;
       pc->output_tokens
         = GNUNET_new_array (pc->output_tokens_len,
                             struct SignedOutputToken);
+
       /* compute non-donau outputs */
+      output_off = 0;
       for (unsigned int i = 0; i<selected->outputs_len; i++)
       {
         const struct TALER_MERCHANT_ContractOutput *output
@@ -3546,14 +3563,18 @@ phase_validate_tokens (struct PayContext *pc)
           GNUNET_assert (0);
           break;
         case TALER_MERCHANT_CONTRACT_OUTPUT_TYPE_TOKEN:
+          cnt = output->details.token.count;
+          GNUNET_assert (output_off + cnt
+                         <= pc->output_tokens_len);
           if (GNUNET_OK !=
               handle_output_token (pc,
                                    output,
-                                   i))
+                                   output_off))
           {
             /* Error is already scheduled from handle_output_token. */
             return;
           }
+          output_off += cnt;
           break;
         case TALER_MERCHANT_CONTRACT_OUTPUT_TYPE_DONATION_RECEIPT:
 #ifndef HAVE_DONAU_DONAU_SERVICE_H
@@ -3575,6 +3596,7 @@ phase_validate_tokens (struct PayContext *pc)
             /* Error is already scheduled from handle_output_donation_receipt. */
             return;
           }
+          output_off += pc->parse_wallet_data.num_bkps;
           continue;
 #endif
         } /* switch on output token */