/*
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 Affero General Public License as published
by the Free Software Foundation, either version 3 of the License,
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
Affero General Public License for more details.
You should have received a copy of the GNU Affero General Public License
along with this program. If not, see .
SPDX-License-Identifier: AGPL3.0-or-later
*/
/**
* @file credential/delegate_misc.c
* @brief Misc API for delegate
*
* @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 "delegate.h"
#include
char*
GNUNET_CREDENTIAL_delegate_to_string (const struct GNUNET_CREDENTIAL_Delegate *cred)
{
char *cred_str;
char *subject_pkey;
char *issuer_pkey;
char *signature;
subject_pkey = GNUNET_CRYPTO_ecdsa_public_key_to_string (&cred->subject_key);
issuer_pkey = GNUNET_CRYPTO_ecdsa_public_key_to_string (&cred->issuer_key);
GNUNET_STRINGS_base64_encode ((char*)&cred->signature,
sizeof (struct GNUNET_CRYPTO_EcdsaSignature),
&signature);
if(0 == cred->subject_attribute_len){
GNUNET_asprintf (&cred_str,
"%s.%s -> %s | %s | %"SCNu64,
issuer_pkey,
cred->issuer_attribute,
subject_pkey,
signature,
cred->expiration.abs_value_us);
} else {
GNUNET_asprintf (&cred_str,
"%s.%s -> %s.%s | %s | %"SCNu64,
issuer_pkey,
cred->issuer_attribute,
subject_pkey,
cred->subject_attribute,
signature,
cred->expiration.abs_value_us);
}
GNUNET_free (subject_pkey);
GNUNET_free (issuer_pkey);
GNUNET_free (signature);
return cred_str;
}
struct GNUNET_CREDENTIAL_Delegate*
GNUNET_CREDENTIAL_delegate_from_string (const char* s)
{
struct GNUNET_CREDENTIAL_Delegate *cred;
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 iss_attr[253 + 1];
// Needs to be initialized, in case of Type 1 credential (A.a <- B)
char sub_attr[253 + 1] = "";
char signature[256]; //TODO max payload size
struct GNUNET_CRYPTO_EcdsaSignature *sig;
struct GNUNET_TIME_Absolute etime_abs;
// If it's A.a <- B.b...
if (6 != SSCANF (s,
"%52s.%253s -> %52s.%253s | %s | %"SCNu64,
issuer_pkey,
iss_attr,
subject_pkey,
sub_attr,
signature,
&etime_abs.abs_value_us))
{
// Try if it's A.a <- B
if (5 != SSCANF (s,
"%52s.%253s -> %52s | %s | %"SCNu64,
issuer_pkey,
iss_attr,
subject_pkey,
signature,
&etime_abs.abs_value_us))
{
GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Unable to parse DEL record string `%s'\n", s);
return NULL;
}
}
// +1 for \0
int attr_len;
if(strcmp(sub_attr,"") == 0) {
attr_len = strlen (iss_attr) + 1;
} else {
attr_len = strlen (iss_attr) + strlen(sub_attr) + 1;
}
cred = GNUNET_malloc (sizeof (struct GNUNET_CREDENTIAL_Delegate) + attr_len);
char tmp_str[attr_len];
GNUNET_memcpy(tmp_str, iss_attr, strlen(iss_attr));
if(strcmp(sub_attr,"") != 0) {
GNUNET_memcpy(tmp_str + strlen(iss_attr), sub_attr, strlen(sub_attr));
}
tmp_str[attr_len - 1] = '\0';
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);
GNUNET_assert (sizeof (struct GNUNET_CRYPTO_EcdsaSignature) == GNUNET_STRINGS_base64_decode (signature,
strlen (signature),
(char**)&sig));
cred->signature = *sig;
cred->expiration = etime_abs;
GNUNET_free (sig);
GNUNET_memcpy (&cred[1],
tmp_str,
attr_len);
cred->issuer_attribute_len = strlen (iss_attr);
cred->issuer_attribute = strdup(iss_attr);
if(strcmp(sub_attr,"") == 0) {
cred->subject_attribute_len = 0;
cred->subject_attribute = '\0';
} else {
cred->subject_attribute_len = strlen (sub_attr);
cred->subject_attribute = strdup(sub_attr);
}
return cred;
}
/**
* Issue an attribute to a subject
*
* @param issuer the ego that should be used to issue the attribute
* @param subject the subject of the attribute
* @param attribute the name of the attribute
* @return handle to the queued request
*/
struct GNUNET_CREDENTIAL_Delegate *
GNUNET_CREDENTIAL_delegate_issue (const struct GNUNET_CRYPTO_EcdsaPrivateKey *issuer,
struct GNUNET_CRYPTO_EcdsaPublicKey *subject,
const char *iss_attr,
const char *sub_attr,
struct GNUNET_TIME_Absolute *expiration)
{
struct DelegateEntry *crd;
struct GNUNET_CREDENTIAL_Delegate *cred;
size_t size;
int attr_len;
if (NULL == sub_attr){
// +1 for \0
attr_len = strlen (iss_attr) + 1;
} else {
attr_len = strlen (iss_attr) + strlen(sub_attr) + 1;
}
size = sizeof (struct DelegateEntry) + attr_len;
char tmp_str[attr_len];
GNUNET_memcpy(tmp_str, iss_attr, strlen(iss_attr));
if (NULL != sub_attr){
GNUNET_memcpy(tmp_str + strlen(iss_attr), sub_attr, strlen(sub_attr));
}
tmp_str[attr_len - 1] = '\0';
crd = GNUNET_malloc (size);
crd->purpose.size = htonl (size - sizeof (struct GNUNET_CRYPTO_EcdsaSignature));
crd->purpose.purpose = htonl (GNUNET_SIGNATURE_PURPOSE_CREDENTIAL);
GNUNET_CRYPTO_ecdsa_key_get_public (issuer,
&crd->issuer_key);
crd->subject_key = *subject;
crd->expiration = GNUNET_htonll (expiration->abs_value_us);
crd->issuer_attribute_len = htonl (strlen (iss_attr) + 1);
if (NULL == sub_attr){
crd->subject_attribute_len = htonl (0);
} else {
crd->subject_attribute_len = htonl (strlen (sub_attr) + 1);
}
GNUNET_memcpy (&crd[1],
tmp_str,
attr_len);
if (GNUNET_OK !=
GNUNET_CRYPTO_ecdsa_sign (issuer,
&crd->purpose,
&crd->signature))
{
GNUNET_break (0);
GNUNET_free (crd);
return NULL;
}
cred = GNUNET_malloc (sizeof (struct GNUNET_CREDENTIAL_Delegate) + attr_len);
cred->signature = crd->signature;
cred->expiration = *expiration;
GNUNET_CRYPTO_ecdsa_key_get_public (issuer,
&cred->issuer_key);
cred->subject_key = *subject;
cred->issuer_attribute = strdup(iss_attr);
cred->issuer_attribute_len = strlen(iss_attr);
if (NULL == sub_attr){
cred->subject_attribute = '\0';
cred->subject_attribute_len = 0;
} else {
cred->subject_attribute = strdup(sub_attr);
cred->subject_attribute_len = strlen(sub_attr);
}
GNUNET_memcpy (&cred[1],
tmp_str,
attr_len);
GNUNET_free (crd);
return cred;
}