1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
|
/*
This file is part of GNUnet
Copyright (C) 2010-2015 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.
*/
/**
* @file identity-provider/jwt.c
* @brief helper library for JSON-Web-Tokens
* @author Martin Schanzenbach
*/
#include "platform.h"
#include "gnunet_util_lib.h"
#include "gnunet_signatures.h"
#include "gnunet_identity_attribute_lib.h"
#include <jansson.h>
#define JWT_ALG "alg"
/*TODO is this the correct way to define new algs? */
#define JWT_ALG_VALUE "urn:org:gnunet:jwt:alg:ecdsa:ed25519"
#define JWT_TYP "typ"
#define JWT_TYP_VALUE "jwt"
//TODO change server address
#define SERVER_ADDRESS "https://localhost"
static char*
create_jwt_header(void)
{
json_t *root;
char *json_str;
root = json_object ();
json_object_set_new (root, JWT_ALG, json_string (JWT_ALG_VALUE));
json_object_set_new (root, JWT_TYP, json_string (JWT_TYP_VALUE));
json_str = json_dumps (root, JSON_INDENT(1));
json_decref (root);
return json_str;
}
/**
* Create a JWT from attributes
*
* @param aud_key the public of the subject
* @param attrs the attribute list
* @param priv_key the key used to sign the JWT
* @return a new base64-encoded JWT string.
*/
char*
jwt_create_from_list (const struct GNUNET_CRYPTO_EcdsaPublicKey *aud_key,
const struct GNUNET_IDENTITY_ATTRIBUTE_ClaimList *attrs,
const struct GNUNET_CRYPTO_EcdsaPrivateKey *priv_key)
{
struct GNUNET_IDENTITY_ATTRIBUTE_ClaimListEntry *le;
struct GNUNET_CRYPTO_EcdsaPublicKey sub_key;
struct GNUNET_CRYPTO_EcdsaSignature signature;
struct GNUNET_CRYPTO_EccSignaturePurpose *purpose;
char* audience;
char* subject;
char* header;
char* padding;
char* body_str;
char* result;
char* header_base64;
char* body_base64;
char* signature_target;
char* signature_base64;
char* attr_val_str;
json_t* body;
//exp REQUIRED time expired from config
//iat REQUIRED time now
//auth_time only if max_age
//nonce only if nonce
// OPTIONAL acr,amr,azp
GNUNET_CRYPTO_ecdsa_key_get_public (priv_key, &sub_key);
/* TODO maybe we should use a local identity here */
subject = GNUNET_STRINGS_data_to_string_alloc (&sub_key,
sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey));
audience = GNUNET_STRINGS_data_to_string_alloc (aud_key,
sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey));
header = create_jwt_header ();
body = json_object ();
/* TODO who is the issuer? local IdP or subject ? See self-issued tokens? */
//iss REQUIRED case sensitive server uri with https
json_object_set_new (body,
"iss", json_string (SERVER_ADDRESS));
//sub REQUIRED public key identity, not exceed 255 ASCII length
json_object_set_new (body,
"sub", json_string (subject));
/* TODO what should be in here exactly? */
//aud REQUIRED public key client_id must be there
json_object_set_new (body,
"aud", json_string (audience));
for (le = attrs->list_head; NULL != le; le = le->next)
{
/**
* TODO here we should have a function that
* calls the Attribute plugins to create a
* json representation for its value
*/
attr_val_str = GNUNET_IDENTITY_ATTRIBUTE_value_to_string (le->claim->type,
le->claim->data,
le->claim->data_size);
json_object_set_new (body,
le->claim->name,
json_string (attr_val_str));
GNUNET_free (attr_val_str);
}
body_str = json_dumps (body, JSON_INDENT(0));
json_decref (body);
GNUNET_STRINGS_base64_encode (header,
strlen (header),
&header_base64);
//Remove GNUNET padding of base64
padding = strtok(header_base64, "=");
while (NULL != padding)
padding = strtok(NULL, "=");
GNUNET_STRINGS_base64_encode (body_str,
strlen (body_str),
&body_base64);
//Remove GNUNET padding of base64
padding = strtok(body_base64, "=");
while (NULL != padding)
padding = strtok(NULL, "=");
GNUNET_free (subject);
GNUNET_free (audience);
/**
* TODO
* Creating the JWT signature. This might not be
* standards compliant, check.
*/
GNUNET_asprintf (&signature_target, "%s,%s", header_base64, body_base64);
purpose =
GNUNET_malloc (sizeof (struct GNUNET_CRYPTO_EccSignaturePurpose) +
strlen (signature_target));
purpose->size =
htonl (strlen (signature_target) + sizeof (struct GNUNET_CRYPTO_EccSignaturePurpose));
purpose->purpose = htonl(GNUNET_SIGNATURE_PURPOSE_GNUID_TOKEN);
GNUNET_memcpy (&purpose[1], signature_target, strlen (signature_target));
if (GNUNET_OK != GNUNET_CRYPTO_ecdsa_sign (priv_key,
purpose,
(struct GNUNET_CRYPTO_EcdsaSignature *)&signature))
{
GNUNET_free (signature_target);
GNUNET_free (body_str);
GNUNET_free (body_base64);
GNUNET_free (header_base64);
GNUNET_free (purpose);
return NULL;
}
GNUNET_STRINGS_base64_encode ((const char*)&signature,
sizeof (struct GNUNET_CRYPTO_EcdsaSignature),
&signature_base64);
GNUNET_asprintf (&result, "%s.%s.%s",
header_base64, body_base64, signature_base64);
GNUNET_free (signature_target);
GNUNET_free (header);
GNUNET_free (body_str);
GNUNET_free (signature_base64);
GNUNET_free (body_base64);
GNUNET_free (header_base64);
GNUNET_free (purpose);
return result;
}
|
