1 files changed, 460 insertions, 0 deletions

diff --git a/src/credential/credential_serialization.c b/src/credential/credential_serialization.c
new file mode 100644
index 000000000..1d23bb08c
--- /dev/null
+++ b/src/credential/credential_serialization.c
@@ -0,0 +1,460 @@
+/*
+     This file is part of GNUnet.
+     Copyright (C) 2009-2013, 2016 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/credential_serialization.c
+ * @brief API to serialize and deserialize delegation chains 
+ * and credentials
+ * @author Martin Schanzenbach
+ */
+#include "platform.h"
+#include "gnunet_util_lib.h"
+#include "gnunet_constants.h"
+#include "gnunet_credential_service.h"
+#include "gnunet_signatures.h"
+#include "credential.h"
+
+/**
+ * Calculate how many bytes we will need to serialize
+ * the given delegation chain
+ *
+ * @param ds_count number of delegation chain entries
+ * @param dsr array of #GNUNET_CREDENTIAL_DelegationSet
+ * @return the required size to serialize
+ */
+size_t
+GNUNET_CREDENTIAL_delegation_set_get_size (unsigned int ds_count,
+                                           const struct GNUNET_CREDENTIAL_DelegationSet *dsr)
+{
+  unsigned int i;
+  size_t ret;
+
+  ret = sizeof (struct DelegationRecordData) * (ds_count);
+
+  for (i=0; i<ds_count;i++)
+  {
+    GNUNET_assert ((ret + dsr[i].subject_attribute_len) >= ret);
+    ret += dsr[i].subject_attribute_len;
+  }
+  return ret;
+}
+
+/**
+ * Serizalize the given delegation chain entries and credential
+ *
+ * @param d_count number of delegation chain entries
+ * @param dsr array of #GNUNET_CREDENTIAL_DelegationSet
+ * @param dest_size size of the destination
+ * @param dest where to store the result
+ * @return the size of the data, -1 on failure
+ */
+ssize_t
+GNUNET_CREDENTIAL_delegation_set_serialize (unsigned int d_count,
+                                            const struct GNUNET_CREDENTIAL_DelegationSet *dsr,
+                                            size_t dest_size,
+                                            char *dest)
+{
+  struct DelegationRecordData rec;
+  unsigned int i;
+  size_t off;
+
+  off = 0;
+  for (i=0;i<d_count;i++)
+  {
+    rec.subject_attribute_len = htonl ((uint32_t) dsr[i].subject_attribute_len);
+    rec.subject_key = dsr[i].subject_key;
+    if (off + sizeof (rec) > dest_size)
+      return -1;
+    GNUNET_memcpy (&dest[off],
+                   &rec,
+                   sizeof (rec));
+    off += sizeof (rec);
+    if (0 == dsr[i].subject_attribute_len)
+      continue;
+    if (off + dsr[i].subject_attribute_len > dest_size)
+      return -1;
+    GNUNET_memcpy (&dest[off],
+                   dsr[i].subject_attribute,
+                   dsr[i].subject_attribute_len);
+    off += dsr[i].subject_attribute_len;
+  }
+  return off;
+}
+
+
+/**
+ * Deserialize the given destination
+ *
+ * @param len size of the serialized delegation chain and cred
+ * @param src the serialized data
+ * @param d_count the number of delegation chain entries
+ * @param dsr where to put the delegation chain entries
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
+ */
+int
+GNUNET_CREDENTIAL_delegation_set_deserialize (size_t len,
+                                              const char *src,
+                                              unsigned int d_count,
+                                              struct GNUNET_CREDENTIAL_DelegationSet *dsr)
+{
+  struct DelegationRecordData rec;
+  unsigned int i;
+  size_t off;
+
+  off = 0;
+  for (i=0;i<d_count;i++)
+  {
+    if (off + sizeof (rec) > len)
+      return GNUNET_SYSERR;
+    GNUNET_memcpy (&rec, &src[off], sizeof (rec));
+    dsr[i].subject_key = rec.subject_key;
+    off += sizeof (rec);
+    dsr[i].subject_attribute_len = ntohl ((uint32_t) rec.subject_attribute_len);
+    if (off + dsr[i].subject_attribute_len > len)
+      return GNUNET_SYSERR;
+    dsr[i].subject_attribute = (char*)&src[off];
+    off += dsr[i].subject_attribute_len;
+  }
+  return GNUNET_OK;
+}
+
+
+/**
+ * Calculate how many bytes we will need to serialize
+ * the credentials
+ *
+ * @param c_count number of credential entries
+ * @param cd a #GNUNET_CREDENTIAL_Credential
+ * @return the required size to serialize
+ */
+size_t
+GNUNET_CREDENTIAL_credentials_get_size (unsigned int c_count,
+                                        const struct GNUNET_CREDENTIAL_Credential *cd)
+{
+  unsigned int i;
+  size_t ret;
+
+  ret = sizeof (struct CredentialEntry) * (c_count);
+
+  for (i=0; i<c_count;i++)
+  {
+    GNUNET_assert ((ret + cd[i].issuer_attribute_len) >= ret);
+    ret += cd[i].issuer_attribute_len;
+  }
+  return ret;
+}
+/**
+ * Serizalize the given credentials
+ *
+ * @param c_count number of credential entries
+ * @param cd a #GNUNET_CREDENTIAL_Credential
+ * @param dest_size size of the destination
+ * @param dest where to store the result
+ * @return the size of the data, -1 on failure
+ */
+ssize_t
+GNUNET_CREDENTIAL_credentials_serialize (unsigned int c_count,
+                                         const struct GNUNET_CREDENTIAL_Credential *cd,
+                                         size_t dest_size,
+                                         char *dest)
+{
+  struct CredentialEntry c_rec;
+  unsigned int i;
+  size_t off;
+
+  off = 0;
+  for (i=0;i<c_count;i++)
+  {
+    c_rec.issuer_attribute_len = htonl ((uint32_t) cd[i].issuer_attribute_len);
+    c_rec.issuer_key = cd[i].issuer_key;
+    c_rec.subject_key = cd[i].subject_key;
+    c_rec.signature = cd[i].signature;
+    c_rec.purpose.purpose = htonl (GNUNET_SIGNATURE_PURPOSE_CREDENTIAL);
+    c_rec.purpose.size = htonl ((sizeof (struct CredentialEntry) + cd[i].issuer_attribute_len) - sizeof (struct GNUNET_CRYPTO_EcdsaSignature));
+    c_rec.expiration = GNUNET_htonll (cd[i].expiration.abs_value_us);
+    if (off + sizeof (c_rec) > dest_size)
+      return -1;
+    GNUNET_memcpy (&dest[off],
+                   &c_rec,
+                   sizeof (c_rec));
+    off += sizeof (c_rec);
+    if (off + cd[i].issuer_attribute_len > dest_size)
+      return -1;
+    GNUNET_memcpy (&dest[off],
+                   cd[i].issuer_attribute,
+                   cd[i].issuer_attribute_len);
+    off += cd[i].issuer_attribute_len;
+  }
+
+  return off;
+}
+
+
+
+/**
+ * Deserialize the given destination
+ *
+ * @param len size of the serialized creds
+ * @param src the serialized data
+ * @param c_count the number of credential entries
+ * @param cd where to put the credential data
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
+ */
+int
+GNUNET_CREDENTIAL_credentials_deserialize (size_t len,
+                                           const char *src,
+                                           unsigned int c_count,
+                                           struct GNUNET_CREDENTIAL_Credential *cd)
+{
+  struct CredentialEntry c_rec;
+  unsigned int i;
+  size_t off;
+
+  off = 0;
+  for (i=0;i<c_count;i++)
+  {
+    if (off + sizeof (c_rec) > len)
+      return GNUNET_SYSERR;
+    GNUNET_memcpy (&c_rec, &src[off], sizeof (c_rec));
+    cd[i].issuer_attribute_len = ntohl ((uint32_t) c_rec.issuer_attribute_len);
+    cd[i].issuer_key = c_rec.issuer_key;
+    cd[i].subject_key = c_rec.subject_key;
+    cd[i].signature = c_rec.signature;
+    cd[i].expiration.abs_value_us = GNUNET_ntohll(c_rec.expiration);
+    off += sizeof (c_rec);
+    if (off + cd[i].issuer_attribute_len > len)
+      return GNUNET_SYSERR;
+    cd[i].issuer_attribute = &src[off];
+    off += cd[i].issuer_attribute_len;
+  }
+  return GNUNET_OK;
+}
+
+
+
+/**
+ * Calculate how many bytes we will need to serialize
+ * the given delegation chain and credential
+ *
+ * @param d_count number of delegation chain entries
+ * @param dd array of #GNUNET_CREDENTIAL_Delegation
+ * @param c_count number of credential entries
+ * @param cd a #GNUNET_CREDENTIAL_Credential
+ * @return the required size to serialize
+ */
+size_t
+GNUNET_CREDENTIAL_delegation_chain_get_size (unsigned int d_count,
+                                             const struct GNUNET_CREDENTIAL_Delegation *dd,
+                                             unsigned int c_count,
+                                             const struct GNUNET_CREDENTIAL_Credential *cd)
+{
+  unsigned int i;
+  size_t ret;
+
+  ret = sizeof (struct ChainEntry) * (d_count);
+
+  for (i=0; i<d_count;i++)
+  {
+    GNUNET_assert ((ret +
+                    dd[i].issuer_attribute_len +
+                    dd[i].subject_attribute_len) >= ret);
+    ret += dd[i].issuer_attribute_len + dd[i].subject_attribute_len;
+  }
+  return ret+GNUNET_CREDENTIAL_credentials_get_size(c_count, cd);
+  return ret;
+}
+
+/**
+ * Serizalize the given delegation chain entries and credential
+ *
+ * @param d_count number of delegation chain entries
+ * @param dd array of #GNUNET_CREDENTIAL_Delegation
+ * @param c_count number of credential entries
+ * @param cd a #GNUNET_CREDENTIAL_Credential
+ * @param dest_size size of the destination
+ * @param dest where to store the result
+ * @return the size of the data, -1 on failure
+ */
+ssize_t
+GNUNET_CREDENTIAL_delegation_chain_serialize (unsigned int d_count,
+                                              const struct GNUNET_CREDENTIAL_Delegation *dd,
+                                              unsigned int c_count,
+                                              const struct GNUNET_CREDENTIAL_Credential *cd,
+                                              size_t dest_size,
+                                              char *dest)
+{
+  struct ChainEntry rec;
+  unsigned int i;
+  size_t off;
+
+  off = 0;
+  for (i=0;i<d_count;i++)
+  {
+    rec.issuer_attribute_len = htonl ((uint32_t) dd[i].issuer_attribute_len);
+    rec.subject_attribute_len = htonl ((uint32_t) dd[i].subject_attribute_len);
+    rec.issuer_key = dd[i].issuer_key;
+    rec.subject_key = dd[i].subject_key;
+    if (off + sizeof (rec) > dest_size)
+      return -1;
+    GNUNET_memcpy (&dest[off],
+                   &rec,
+                   sizeof (rec));
+    off += sizeof (rec);
+    if (off + dd[i].issuer_attribute_len > dest_size)
+      return -1;
+    GNUNET_memcpy (&dest[off],
+                   dd[i].issuer_attribute,
+                   dd[i].issuer_attribute_len);
+    off += dd[i].issuer_attribute_len;
+    if (0 == dd[i].subject_attribute_len)
+      continue;
+    if (off + dd[i].subject_attribute_len > dest_size)
+      return -1;
+    GNUNET_memcpy (&dest[off],
+                   dd[i].subject_attribute,
+                   dd[i].subject_attribute_len);
+    off += dd[i].subject_attribute_len;
+  }
+  return off+GNUNET_CREDENTIAL_credentials_serialize (c_count,
+                                                      cd,
+                                                      dest_size-off,
+                                                      &dest[off]);
+}
+
+
+/**
+ * Deserialize the given destination
+ *
+ * @param len size of the serialized delegation chain and cred
+ * @param src the serialized data
+ * @param d_count the number of delegation chain entries
+ * @param dd where to put the delegation chain entries
+ * @param c_count the number of credential entries
+ * @param cd where to put the credential data
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
+ */
+int
+GNUNET_CREDENTIAL_delegation_chain_deserialize (size_t len,
+                                                const char *src,
+                                                unsigned int d_count,
+                                                struct GNUNET_CREDENTIAL_Delegation *dd,
+                                                unsigned int c_count,
+                                                struct GNUNET_CREDENTIAL_Credential *cd)
+{
+  struct ChainEntry rec;
+  unsigned int i;
+  size_t off;
+
+  off = 0;
+  for (i=0;i<d_count;i++)
+  {
+    if (off + sizeof (rec) > len)
+      return GNUNET_SYSERR;
+    GNUNET_memcpy (&rec, &src[off], sizeof (rec));
+    dd[i].issuer_attribute_len = ntohl ((uint32_t) rec.issuer_attribute_len);
+    dd[i].issuer_key = rec.issuer_key;
+    dd[i].subject_key = rec.subject_key;
+    off += sizeof (rec);
+    if (off + dd[i].issuer_attribute_len > len)
+      return GNUNET_SYSERR;
+    dd[i].issuer_attribute = &src[off];
+    off += dd[i].issuer_attribute_len;
+    dd[i].subject_attribute_len = ntohl ((uint32_t) rec.subject_attribute_len);
+    if (off + dd[i].subject_attribute_len > len)
+      return GNUNET_SYSERR;
+    dd[i].subject_attribute = &src[off];
+    off += dd[i].subject_attribute_len;
+  }
+  return GNUNET_CREDENTIAL_credentials_deserialize (len-off,
+                                                    &src[off],
+                                                    c_count,
+                                                    cd);
+}
+int
+GNUNET_CREDENTIAL_credential_serialize (struct GNUNET_CREDENTIAL_Credential *cred,
+                                        char **data)
+{
+  size_t size;
+  struct CredentialEntry *cdata;
+
+  size = sizeof (struct CredentialEntry) + strlen (cred->issuer_attribute) + 1;
+  *data = GNUNET_malloc (size);
+  cdata = (struct CredentialEntry*)*data;
+  cdata->subject_key = cred->subject_key;
+  cdata->issuer_key = cred->issuer_key;
+  cdata->expiration = GNUNET_htonll (cred->expiration.abs_value_us);
+  cdata->signature = cred->signature;
+  cdata->issuer_attribute_len = htonl (strlen (cred->issuer_attribute) + 1);
+  cdata->purpose.purpose = htonl (GNUNET_SIGNATURE_PURPOSE_CREDENTIAL);
+  cdata->purpose.size = htonl (size - sizeof (struct GNUNET_CRYPTO_EcdsaSignature));
+  GNUNET_memcpy (&cdata[1],
+                 cred->issuer_attribute,
+                 strlen (cred->issuer_attribute));
+
+  if(GNUNET_OK != GNUNET_CRYPTO_ecdsa_verify(GNUNET_SIGNATURE_PURPOSE_CREDENTIAL, 
+                                             &cdata->purpose,
+                                             &cdata->signature,
+                                             &cdata->issuer_key))
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+                "Invalid credential\n");
+    //return NULL;
+  }
+  return size;
+}
+
+struct GNUNET_CREDENTIAL_Credential*
+GNUNET_CREDENTIAL_credential_deserialize (const char* data,
+                                          size_t data_size)
+{
+  struct GNUNET_CREDENTIAL_Credential *cred;
+  struct CredentialEntry *cdata;
+  char *issuer_attribute;
+
+  if (data_size < sizeof (struct CredentialEntry))
+    return NULL;
+  cdata = (struct CredentialEntry*)data;
+  if(GNUNET_OK != GNUNET_CRYPTO_ecdsa_verify(GNUNET_SIGNATURE_PURPOSE_CREDENTIAL, 
+                                             &cdata->purpose,
+                                             &cdata->signature,
+                                             &cdata->issuer_key))
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+                "Invalid credential\n");
+    //return NULL;
+  }
+  issuer_attribute = (char*)&cdata[1];
+
+  cred = GNUNET_malloc (sizeof (struct GNUNET_CREDENTIAL_Credential) + ntohl(cdata->issuer_attribute_len));
+
+  cred->issuer_key = cdata->issuer_key;
+  cred->subject_key = cdata->subject_key;
+  GNUNET_memcpy (&cred[1],
+                 issuer_attribute,
+                 ntohl (cdata->issuer_attribute_len));
+  cred->signature = cdata->signature;
+  cred->issuer_attribute = (char*)&cred[1];
+  cred->expiration.abs_value_us = GNUNET_ntohll (cdata->expiration);
+  return cred;
+}
+
+
+/* end of credential_serialization.c */