1 files changed, 257 insertions, 0 deletions

diff --git a/src/credential/plugin_gnsrecord_credential.c b/src/credential/plugin_gnsrecord_credential.c
new file mode 100644
index 000000000..6ae3b8980
--- /dev/null
+++ b/src/credential/plugin_gnsrecord_credential.c
@@ -0,0 +1,257 @@
+/*
+     This file is part of GNUnet
+     Copyright (C) 2013 GNUnet e.V.
+
+     GNUnet is free software; you can redistribute it and/or modify
+     it under the terms of the GNU General Public License as published
+     by the Free Software Foundation; either version 3, or (at your
+     option) any later version.
+
+     GNUnet 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
+     General Public License for more details.
+
+     You should have received a copy of the GNU General Public License
+     along with GNUnet; see the file COPYING.  If not, write to the
+     Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+     Boston, MA 02110-1301, USA.
+*/
+
+/**
+ * @file credential/plugin_gnsrecord_credential.c
+ * @brief gnsrecord plugin to provide the API for CREDENTIAL records
+ * @author Adnan Husain
+ */
+
+#include "platform.h"
+#include "gnunet_util_lib.h"
+#include "gnunet_gnsrecord_lib.h"
+#include "gnunet_credential_service.h"
+#include "gnunet_gnsrecord_plugin.h"
+
+
+/**
+ * Convert the 'value' of a record to a string.
+ *
+ * @param cls closure, unused
+ * @param type type of the record
+ * @param data value in binary encoding
+ * @param data_size number of bytes in @a data
+ * @return NULL on error, otherwise human-readable representation of the value
+ */
+static char *
+credential_value_to_string (void *cls,
+                              uint32_t type,
+                              const void *data,
+                              size_t data_size)
+{
+
+  const char *cdata;
+
+  switch (type)
+  {
+   case GNUNET_GNSRECORD_TYPE_CREDENTIAL:
+   {
+    struct GNUNET_CREDENTIAL_RecordData cred;
+    char *cred_str;
+    char *subject_pkey;
+    char *issuer_pkey;
+    uint32_t cf; // Credential flags
+    uint32_t mdd; // Max delegation depth
+    if (data_size < sizeof (struct GNUNET_CREDENTIAL_RecordData))
+        return NULL; /* malformed */
+    memcpy (&cred,
+              data,
+              sizeof (cred));
+    cdata = data;  
+    subject_pkey = GNUNET_CRYPTO_ecdsa_public_key_to_string (&cred.subject_key);
+    issuer_pkey = GNUNET_CRYPTO_ecdsa_public_key_to_string (&cred.issuer_key);
+    cf = ntohl (cred.credential_flags);
+    mdd = ntohl (cred.max_delegation_depth);
+
+     GNUNET_asprintf (&cred_str,
+                     "%s %s %u %u %s",
+                     subject_pkey,
+                     issuer_pkey,
+                     (unsigned int) cf,
+                     (unsigned int) mdd,
+                     &cdata[sizeof (cred)]);
+      GNUNET_free (subject_pkey);
+      GNUNET_free (issuer_pkey);
+
+
+
+    return cred_str;
+    }
+  default:
+    return NULL;
+  }
+}
+
+
+/**
+ * Convert human-readable version of a 'value' of a record to the binary
+ * representation.
+ *
+ * @param cls closure, unused
+ * @param type type of the record
+ * @param s human-readable string
+ * @param data set to value in binary encoding (will be allocated)
+ * @param data_size set to number of bytes in @a data
+ * @return #GNUNET_OK on success
+ */
+static int
+credential_string_to_value (void *cls,
+                     uint32_t type,
+                     const char *s,
+                     void **data,
+                     size_t *data_size)
+{
+  if (NULL == s)
+    return GNUNET_SYSERR;
+  switch (type)
+  {
+   case GNUNET_GNSRECORD_TYPE_CREDENTIAL:
+    { 
+      struct GNUNET_CREDENTIAL_RecordData *cred;
+      unsigned int cf; // credential flags
+      unsigned int mdd; // max delegation depth
+
+      size_t enclen = (sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey)) * 8;
+        if (enclen % 5 > 0)
+          enclen += 5 - enclen % 5;
+        enclen /= 5; /* 260/5 = 52 */
+      char subject_pkey[enclen + 1];
+      char issuer_pkey[enclen + 1];
+      char name[253 + 1];
+
+      if (5 != SSCANF (s,
+                         "%52s %52s %u %u %253s",
+                         subject_pkey,
+                         issuer_pkey,
+                         &cf,
+                         &mdd,
+                         name))
+        {
+          GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                      _("Unable to parse CRED record string `%s'\n"),
+                      s);
+          return GNUNET_SYSERR;
+        }
+        *data_size = sizeof (struct GNUNET_CREDENTIAL_RecordData) + strlen (name) + 1;
+        *data = cred = GNUNET_malloc (*data_size);
+        GNUNET_CRYPTO_ecdsa_public_key_from_string (subject_pkey,
+                                                    strlen (subject_pkey),
+                                                    &cred->subject_key);
+        GNUNET_CRYPTO_ecdsa_public_key_from_string (issuer_pkey,
+                                                    strlen (issuer_pkey),
+                                                    &cred->issuer_key);
+        cred->credential_flags = htonl (cf);
+        cred->max_delegation_depth = htonl (mdd);
+        GNUNET_memcpy (&cred[1],
+                       name,
+                       strlen (name));
+
+
+      *data = GNUNET_strdup (s);
+      *data_size = strlen (s);
+      return GNUNET_OK;
+    }
+  default:
+    return GNUNET_SYSERR;
+  }
+}
+
+
+/**
+ * Mapping of record type numbers to human-readable
+ * record type names.
+ */
+static struct {
+  const char *name;
+  uint32_t number;
+} name_map[] = {
+  { "CRED", GNUNET_GNSRECORD_TYPE_CREDENTIAL },
+  { NULL, UINT32_MAX }
+};
+
+
+/**
+ * Convert a type name (i.e. "AAAA") to the corresponding number.
+ *
+ * @param cls closure, unused
+ * @param gns_typename name to convert
+ * @return corresponding number, UINT32_MAX on error
+ */
+static uint32_t
+credential_typename_to_number (void *cls,
+                        const char *gns_typename)
+{
+  unsigned int i;
+
+  i=0;
+  while ( (name_map[i].name != NULL) &&
+          (0 != strcasecmp (gns_typename, name_map[i].name)) )
+    i++;
+  return name_map[i].number;
+}
+
+
+/**
+ * Convert a type number (i.e. 1) to the corresponding type string (i.e. "A")
+ *
+ * @param cls closure, unused
+ * @param type number of a type to convert
+ * @return corresponding typestring, NULL on error
+ */
+static const char *
+credential_number_to_typename (void *cls,
+                        uint32_t type)
+{
+  unsigned int i;
+
+  i=0;
+  while ( (name_map[i].name != NULL) &&
+          (type != name_map[i].number) )
+    i++;
+  return name_map[i].name;
+}
+
+
+/**
+ * Entry point for the plugin.
+ *
+ * @param cls NULL
+ * @return the exported block API
+ */
+void *
+libgnunet_plugin_gnsrecord_credential_init (void *cls)
+{
+  struct GNUNET_GNSRECORD_PluginFunctions *api;
+
+  api = GNUNET_new (struct GNUNET_GNSRECORD_PluginFunctions);
+  api->value_to_string = &credential_value_to_string;
+  api->string_to_value = &credential_string_to_value;
+  api->typename_to_number = &credential_typename_to_number;
+  api->number_to_typename = &credential_number_to_typename;
+  return api;
+}
+
+
+/**
+ * Exit point from the plugin.
+ *
+ * @param cls the return value from #libgnunet_plugin_block_test_init
+ * @return NULL
+ */
+void *
+libgnunet_plugin_gnsrecord_credential_done (void *cls)
+{
+  struct GNUNET_GNSRECORD_PluginFunctions *api = cls;
+
+  GNUNET_free (api);
+  return NULL;
+}
+
+/* end of plugin_gnsrecord_credential.c */