better logging if IBAN validation fails, also avoid potentially unbounded stack allocation

2 files changed, 22 insertions, 1 deletions

diff --git a/src/exchange-lib/exchange_api_reserve.c b/src/exchange-lib/exchange_api_reserve.c
index 40c9d491d..6af500ee2 100644
--- a/src/exchange-lib/exchange_api_reserve.c
+++ b/src/exchange-lib/exchange_api_reserve.c
@@ -827,7 +827,20 @@ reserve_withdraw_payment_required (struct TALER_EXCHANGE_ReserveWithdrawHandle *
      total incoming and outgoing amounts */
   len = json_array_size (history);
   {
-    struct TALER_EXCHANGE_ReserveHistory rhistory[len];
+    struct TALER_EXCHANGE_ReserveHistory *rhistory;
+
+    /* Use heap allocation as "len" may be very big and thus this may
+       not fit on the stack. Use "GNUNET_malloc_large" as a malicious
+       exchange may theoretically try to crash us by giving a history
+       that does not fit into our memory. */
+    rhistory = GNUNET_malloc_large (sizeof (struct TALER_EXCHANGE_ReserveHistory) * len);
+    if (NULL == rhistory)
+    {
+      GNUNET_break (0);
+      free_rhistory (rhistory,
+                     len);
+      return GNUNET_SYSERR;
+    }
 
     if (GNUNET_OK !=
         parse_reserve_history (wsh->exchange,
diff --git a/src/wire/plugin_wire_sepa.c b/src/wire/plugin_wire_sepa.c
index f0cef029f..5de3472b9 100644
--- a/src/wire/plugin_wire_sepa.c
+++ b/src/wire/plugin_wire_sepa.c
@@ -292,7 +292,10 @@ validate_iban (const char *iban)
 
   len = strlen (iban);
   if (len > 34)
+  {
+    GNUNET_break_op (0);
     return GNUNET_NO;
+  }
   strncpy (cc, iban, 2);
   strncpy (ibancpy, iban + 4, len - 4);
   strncpy (ibancpy + len - 4, iban, 4);
@@ -305,7 +308,10 @@ validate_iban (const char *iban)
                sizeof (country_table) / sizeof (struct table_entry),
                sizeof (struct table_entry),
                &cmp_country_code))
+  {
+    GNUNET_break_op (0);
     return GNUNET_NO;
+  }
   nbuf = GNUNET_malloc ((len * 2) + 1);
   for (i=0, j=0; i < len; i++)
   {
@@ -338,6 +344,7 @@ validate_iban (const char *iban)
                        &nread)))
     {
       GNUNET_free (nbuf);
+      GNUNET_break_op (0);
       return GNUNET_NO;
     }
     if (0 != remainder)
@@ -347,6 +354,7 @@ validate_iban (const char *iban)
   GNUNET_free (nbuf);
   if (1 == remainder)
     return GNUNET_YES;
+  GNUNET_break_op (0); /* checksum wrong */
   return GNUNET_NO;
 }