fixing #4230 in bank-lib

1 files changed, 525 insertions, 0 deletions

diff --git a/src/exchange-lib/exchange_api_json.c b/src/exchange-lib/exchange_api_json.c
new file mode 100644
index 000000000..d91feba0e
--- /dev/null
+++ b/src/exchange-lib/exchange_api_json.c
@@ -0,0 +1,525 @@
+/*
+  This file is part of TALER
+  Copyright (C) 2014, 2015 GNUnet e.V.
+
+  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, If not, see <http://www.gnu.org/licenses/>
+*/
+/**
+ * @file exchange-lib/exchange_api_json.c
+ * @brief functions to parse incoming requests (JSON snippets)
+ * @author Florian Dold
+ * @author Benedikt Mueller
+ * @author Christian Grothoff
+ */
+#include "platform.h"
+#include "exchange_api_json.h"
+
+/**
+ * Navigate and parse data in a JSON tree.
+ *
+ * @param root the JSON node to start the navigation at.
+ * @param spec parse specification array
+ * @return offset in @a spec where parsing failed, -1 on success (!)
+ */
+static int
+parse_json (json_t *root,
+            struct MAJ_Specification *spec)
+{
+  int i;
+  json_t *pos; /* what's our current position? */
+
+  pos = root;
+  for (i=0;MAJ_CMD_END != spec[i].cmd;i++)
+  {
+    pos = json_object_get (root,
+                           spec[i].field);
+    if (NULL == pos)
+    {
+      GNUNET_break_op (0);
+      return i;
+    }
+    switch (spec[i].cmd)
+    {
+    case MAJ_CMD_END:
+      GNUNET_assert (0);
+      return i;
+    case MAJ_CMD_AMOUNT:
+      if (GNUNET_OK !=
+          TALER_json_to_amount (pos,
+                                spec[i].details.amount))
+      {
+        GNUNET_break_op (0);
+        return i;
+      }
+      break;
+    case MAJ_CMD_TIME_ABSOLUTE:
+      if (GNUNET_OK !=
+          TALER_json_to_abs (pos,
+                             spec[i].details.abs_time))
+      {
+        GNUNET_break_op (0);
+        return i;
+      }
+      break;
+
+    case MAJ_CMD_STRING:
+      {
+        const char *str;
+
+        str = json_string_value (pos);
+        if (NULL == str)
+        {
+          GNUNET_break_op (0);
+          return i;
+        }
+        *spec[i].details.strptr = str;
+      }
+      break;
+
+    case MAJ_CMD_BINARY_FIXED:
+      {
+        const char *str;
+        int res;
+
+        str = json_string_value (pos);
+        if (NULL == str)
+        {
+          GNUNET_break_op (0);
+          return i;
+        }
+        res = GNUNET_STRINGS_string_to_data (str, strlen (str),
+                                             spec[i].details.fixed_data.dest,
+                                             spec[i].details.fixed_data.dest_size);
+        if (GNUNET_OK != res)
+        {
+          GNUNET_break_op (0);
+          return i;
+        }
+      }
+      break;
+
+    case MAJ_CMD_BINARY_VARIABLE:
+      {
+        const char *str;
+        size_t size;
+        void *data;
+        int res;
+
+        str = json_string_value (pos);
+        if (NULL == str)
+        {
+          GNUNET_break_op (0);
+          return i;
+        }
+        size = (strlen (str) * 5) / 8;
+        if (size >= 1024)
+        {
+          GNUNET_break_op (0);
+          return i;
+        }
+        data = GNUNET_malloc (size);
+        res = GNUNET_STRINGS_string_to_data (str,
+                                             strlen (str),
+                                             data,
+                                             size);
+        if (GNUNET_OK != res)
+        {
+          GNUNET_break_op (0);
+          GNUNET_free (data);
+          return i;
+        }
+        *spec[i].details.variable_data.dest_p = data;
+        *spec[i].details.variable_data.dest_size_p = size;
+      }
+      break;
+
+    case MAJ_CMD_RSA_PUBLIC_KEY:
+      {
+        size_t size;
+        const char *str;
+        int res;
+        void *buf;
+
+        str = json_string_value (pos);
+        if (NULL == str)
+        {
+          GNUNET_break_op (0);
+          return i;
+        }
+        size = (strlen (str) * 5) / 8;
+        buf = GNUNET_malloc (size);
+        res = GNUNET_STRINGS_string_to_data (str,
+                                             strlen (str),
+                                             buf,
+                                             size);
+        if (GNUNET_OK != res)
+        {
+          GNUNET_free (buf);
+          GNUNET_break_op (0);
+          return i;
+        }
+        *spec[i].details.rsa_public_key
+          = GNUNET_CRYPTO_rsa_public_key_decode (buf,
+                                                 size);
+        GNUNET_free (buf);
+        if (NULL == spec[i].details.rsa_public_key)
+        {
+          GNUNET_break_op (0);
+          return i;
+        }
+      }
+      break;
+
+    case MAJ_CMD_RSA_SIGNATURE:
+      {
+        size_t size;
+        const char *str;
+        int res;
+        void *buf;
+
+        str = json_string_value (pos);
+        if (NULL == str)
+        {
+          GNUNET_break_op (0);
+          return i;
+        }
+        size = (strlen (str) * 5) / 8;
+        buf = GNUNET_malloc (size);
+        res = GNUNET_STRINGS_string_to_data (str,
+                                             strlen (str),
+                                             buf,
+                                             size);
+        if (GNUNET_OK != res)
+        {
+          GNUNET_free (buf);
+          GNUNET_break_op (0);
+          return i;
+        }
+        *spec[i].details.rsa_signature
+          = GNUNET_CRYPTO_rsa_signature_decode (buf,
+                                                size);
+        GNUNET_free (buf);
+        if (NULL == spec[i].details.rsa_signature)
+          return i;
+      }
+      break;
+
+    case MAJ_CMD_UINT16:
+      {
+        json_int_t val;
+
+        if (! json_is_integer (pos))
+        {
+          GNUNET_break_op (0);
+          return i;
+        }
+        val = json_integer_value (pos);
+        if ( (0 > val) || (val > UINT16_MAX) )
+        {
+          GNUNET_break_op (0);
+          return i;
+        }
+        *spec[i].details.u16 = (uint16_t) val;
+      }
+      break;
+
+    case MAJ_CMD_UINT64:
+      {
+        json_int_t val;
+
+        if (! json_is_integer (pos))
+        {
+          GNUNET_break_op (0);
+          return i;
+        }
+        val = json_integer_value (pos);
+        *spec[i].details.u64 = (uint64_t) val;
+      }
+      break;
+
+    case MAJ_CMD_JSON_OBJECT:
+      {
+        if (! (json_is_object (pos) || json_is_array (pos)) )
+        {
+          GNUNET_break_op (0);
+          return i;
+        }
+        json_incref (pos);
+        *spec[i].details.obj = pos;
+      }
+      break;
+
+    default:
+      GNUNET_break (0);
+      return i;
+    }
+  }
+  return -1; /* all OK! */
+}
+
+
+/**
+ * Free all elements allocated during a
+ * #MAJ_parse_json() operation.
+ *
+ * @param spec specification of the parse operation
+ * @param end number of elements in @a spec to process
+ */
+static void
+parse_free (struct MAJ_Specification *spec,
+            int end)
+{
+  int i;
+
+  for (i=0;i<end;i++)
+  {
+    switch (spec[i].cmd)
+    {
+    case MAJ_CMD_END:
+      GNUNET_assert (0);
+      return;
+    case MAJ_CMD_AMOUNT:
+      break;
+    case MAJ_CMD_TIME_ABSOLUTE:
+      break;
+    case MAJ_CMD_BINARY_FIXED:
+      break;
+    case MAJ_CMD_STRING:
+      break;
+    case MAJ_CMD_BINARY_VARIABLE:
+      GNUNET_free (*spec[i].details.variable_data.dest_p);
+      *spec[i].details.variable_data.dest_p = NULL;
+      *spec[i].details.variable_data.dest_size_p = 0;
+      break;
+    case MAJ_CMD_RSA_PUBLIC_KEY:
+      GNUNET_CRYPTO_rsa_public_key_free (*spec[i].details.rsa_public_key);
+      *spec[i].details.rsa_public_key = NULL;
+      break;
+    case MAJ_CMD_RSA_SIGNATURE:
+      GNUNET_CRYPTO_rsa_signature_free (*spec[i].details.rsa_signature);
+      *spec[i].details.rsa_signature = NULL;
+      break;
+    case MAJ_CMD_JSON_OBJECT:
+      json_decref (*spec[i].details.obj);
+      *spec[i].details.obj = NULL;
+      break;
+    default:
+      GNUNET_break (0);
+      break;
+    }
+  }
+}
+
+
+/**
+ * Navigate and parse data in a JSON tree.
+ *
+ * @param root the JSON node to start the navigation at.
+ * @param spec parse specification array
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
+ */
+int
+MAJ_parse_json (const json_t *root,
+                struct MAJ_Specification *spec)
+{
+  int ret;
+
+  ret = parse_json ((json_t *) root,
+                    spec);
+  if (-1 == ret)
+    return GNUNET_OK;
+  GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+              "JSON field `%s` (%d) had unexpected value\n",
+              spec[ret].field,
+              ret);
+  parse_free (spec, ret);
+  return GNUNET_SYSERR;
+}
+
+
+/**
+ * Free all elements allocated during a
+ * #MAJ_parse_json() operation.
+ *
+ * @param spec specification of the parse operation
+ */
+void
+MAJ_parse_free (struct MAJ_Specification *spec)
+{
+  int i;
+
+  for (i=0;MAJ_CMD_END != spec[i].cmd;i++) ;
+  parse_free (spec, i);
+}
+
+
+/**
+ * The expected field stores a string.
+ *
+ * @param name name of the JSON field
+ * @param strptr where to store a pointer to the field
+ */
+struct MAJ_Specification
+MAJ_spec_string (const char *name,
+                 const char **strptr)
+{
+  struct MAJ_Specification ret =
+    {
+      .cmd = MAJ_CMD_STRING,
+      .field = name,
+      .details.strptr = strptr
+    };
+  return ret;
+}
+
+
+/**
+ * Specification for parsing an absolute time value.
+ *
+ * @param name name of the JSON field
+ * @param at where to store the absolute time found under @a name
+ */
+struct MAJ_Specification
+MAJ_spec_absolute_time (const char *name,
+                        struct GNUNET_TIME_Absolute *at)
+{
+  struct MAJ_Specification ret =
+    {
+      .cmd = MAJ_CMD_TIME_ABSOLUTE,
+      .field = name,
+      .details.abs_time = at
+    };
+  return ret;
+}
+
+
+/**
+ * Specification for parsing an amount value.
+ *
+ * @param name name of the JSON field
+ * @param amount where to store the amount found under @a name
+ */
+struct MAJ_Specification
+MAJ_spec_amount (const char *name,
+                 struct TALER_Amount *amount)
+{
+  struct MAJ_Specification ret =
+    {
+      .cmd = MAJ_CMD_AMOUNT,
+      .field = name,
+      .details.amount = amount
+    };
+  return ret;
+}
+
+
+/**
+ * 16-bit integer.
+ *
+ * @param name name of the JSON field
+ * @param[out] u16 where to store the integer found under @a name
+ */
+struct MAJ_Specification
+MAJ_spec_uint16 (const char *name,
+                 uint16_t *u16)
+{
+  struct MAJ_Specification ret =
+    {
+      .cmd = MAJ_CMD_UINT16,
+      .field = name,
+      .details.u16 = u16
+    };
+  return ret;
+}
+
+
+/**
+ * 64-bit integer.
+ *
+ * @param name name of the JSON field
+ * @param[out] u64 where to store the integer found under @a name
+ */
+struct MAJ_Specification
+MAJ_spec_uint64 (const char *name,
+                 uint64_t *u64)
+{
+  struct MAJ_Specification ret =
+    {
+      .cmd = MAJ_CMD_UINT64,
+      .field = name,
+      .details.u64 = u64
+    };
+  return ret;
+}
+
+
+/**
+ * JSON object.
+ *
+ * @param name name of the JSON field
+ * @param[out] jsonp where to store the JSON found under @a name
+ */
+struct MAJ_Specification
+MAJ_spec_json (const char *name,
+               json_t **jsonp)
+{
+  struct MAJ_Specification ret =
+    {
+      .cmd = MAJ_CMD_JSON_OBJECT,
+      .field = name,
+      .details.obj = jsonp
+    };
+  return ret;
+}
+
+
+/**
+ * Specification for parsing an RSA public key.
+ *
+ * @param name name of the JSON field
+ * @param pk where to store the RSA key found under @a name
+ */
+struct MAJ_Specification
+MAJ_spec_rsa_public_key (const char *name,
+                         struct GNUNET_CRYPTO_rsa_PublicKey **pk)
+{
+  struct MAJ_Specification ret =
+    {
+      .cmd = MAJ_CMD_RSA_PUBLIC_KEY,
+      .field = name,
+      .details.rsa_public_key = pk
+    };
+  return ret;
+}
+
+
+/**
+ * Specification for parsing an RSA signature.
+ *
+ * @param name name of the JSON field
+ * @param sig where to store the RSA signature found under @a name
+ */
+struct MAJ_Specification
+MAJ_spec_rsa_signature (const char *name,
+                        struct GNUNET_CRYPTO_rsa_Signature **sig)
+{
+  struct MAJ_Specification ret =
+    {
+      .cmd = MAJ_CMD_RSA_SIGNATURE,
+      .field = name,
+      .details.rsa_signature = sig
+    };
+  return ret;
+}
+
+
+/* end of exchange_api_json.c */