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3 Copyright (C) 2010-2015 GNUnet e.V.
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6 under the terms of the GNU Affero General Public License as published
7 by the Free Software Foundation, either version 3 of the License,
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11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Affero General Public License for more details.
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16 along with this program. If not, see <http://www.gnu.org/licenses/>.
18 SPDX-License-Identifier: AGPL3.0-or-later
22 * @file reclaim/oidc_helper.c
23 * @brief helper library for OIDC related functions
24 * @author Martin Schanzenbach
30 #include "gnunet_util_lib.h"
32 #include "gnunet_reclaim_attribute_lib.h"
33 #include "gnunet_reclaim_service.h"
34 #include "gnunet_signatures.h"
35 #include "oidc_helper.h"
37 create_jwt_header (void)
42 root = json_object ();
43 json_object_set_new (root, JWT_ALG, json_string (JWT_ALG_VALUE));
44 json_object_set_new (root, JWT_TYP, json_string (JWT_TYP_VALUE));
46 json_str = json_dumps (root, JSON_INDENT (0) | JSON_COMPACT);
52 replace_char (char *str, char find, char replace)
54 char *current_pos = strchr (str, find);
57 *current_pos = replace;
58 current_pos = strchr (current_pos, find);
64 fix_base64 (char *str)
67 replace_char (str, '+', '-');
70 replace_char (str, '/', '_');
74 * Create a JWT from attributes
76 * @param aud_key the public of the audience
77 * @param sub_key the public key of the subject
78 * @param attrs the attribute list
79 * @param expiration_time the validity of the token
80 * @param secret_key the key used to sign the JWT
81 * @return a new base64-encoded JWT string.
84 OIDC_id_token_new (const struct GNUNET_CRYPTO_EcdsaPublicKey *aud_key,
85 const struct GNUNET_CRYPTO_EcdsaPublicKey *sub_key,
86 const struct GNUNET_RECLAIM_ATTRIBUTE_ClaimList *attrs,
87 const struct GNUNET_TIME_Relative *expiration_time,
89 const char *secret_key)
91 struct GNUNET_RECLAIM_ATTRIBUTE_ClaimListEntry *le;
92 struct GNUNET_HashCode signature;
93 struct GNUNET_TIME_Absolute exp_time;
94 struct GNUNET_TIME_Absolute time_now;
102 char *signature_target;
103 char *signature_base64;
107 // iat REQUIRED time now
108 time_now = GNUNET_TIME_absolute_get ();
109 // exp REQUIRED time expired from config
110 exp_time = GNUNET_TIME_absolute_add (time_now, *expiration_time);
111 // auth_time only if max_age
112 // nonce only if nonce
113 // OPTIONAL acr,amr,azp
114 subject = GNUNET_STRINGS_data_to_string_alloc (
116 sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey));
117 audience = GNUNET_STRINGS_data_to_string_alloc (
119 sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey));
120 header = create_jwt_header ();
121 body = json_object ();
123 // iss REQUIRED case sensitive server uri with https
124 // The issuer is the local reclaim instance (e.g.
125 // https://reclaim.id/api/openid)
126 json_object_set_new (body, "iss", json_string (SERVER_ADDRESS));
127 // sub REQUIRED public key identity, not exceed 255 ASCII length
128 json_object_set_new (body, "sub", json_string (subject));
129 // aud REQUIRED public key client_id must be there
130 json_object_set_new (body, "aud", json_string (audience));
132 json_object_set_new (body,
134 json_integer (time_now.abs_value_us / (1000 * 1000)));
136 json_object_set_new (body,
138 json_integer (exp_time.abs_value_us / (1000 * 1000)));
140 json_object_set_new (body,
142 json_integer (time_now.abs_value_us / (1000 * 1000)));
145 json_object_set_new (body, "nonce", json_string (nonce));
147 for (le = attrs->list_head; NULL != le; le = le->next)
150 GNUNET_RECLAIM_ATTRIBUTE_value_to_string (le->claim->type,
152 le->claim->data_size);
153 json_object_set_new (body, le->claim->name, json_string (attr_val_str));
154 GNUNET_free (attr_val_str);
156 body_str = json_dumps (body, JSON_INDENT (0) | JSON_COMPACT);
159 GNUNET_STRINGS_base64_encode (header, strlen (header), &header_base64);
160 fix_base64 (header_base64);
162 GNUNET_STRINGS_base64_encode (body_str, strlen (body_str), &body_base64);
163 fix_base64 (body_base64);
165 GNUNET_free (subject);
166 GNUNET_free (audience);
169 * Creating the JWT signature. This might not be
170 * standards compliant, check.
172 GNUNET_asprintf (&signature_target, "%s.%s", header_base64, body_base64);
173 GNUNET_CRYPTO_hmac_raw (secret_key,
176 strlen (signature_target),
178 GNUNET_STRINGS_base64_encode ((const char *) &signature,
179 sizeof (struct GNUNET_HashCode),
181 fix_base64 (signature_base64);
183 GNUNET_asprintf (&result,
189 GNUNET_free (signature_target);
190 GNUNET_free (header);
191 GNUNET_free (body_str);
192 GNUNET_free (signature_base64);
193 GNUNET_free (body_base64);
194 GNUNET_free (header_base64);
200 * Returns base64 encoded string urlencoded
202 * @param string the string to encode
203 * @return base64 encoded string
206 base64_encode (const char *data,
215 GNUNET_STRINGS_base64_encode (data, data_size, &enc);
216 tmp = strchr (enc, '=');
217 num_pads = strlen (enc) - (tmp - enc);
218 GNUNET_assert ((3 > num_pads) && (0 <= num_pads));
221 enc_urlencode = GNUNET_malloc (strlen (enc) + num_pads * 2);
222 strcpy (enc_urlencode, enc);
224 tmp = strchr (enc_urlencode, '=');
225 for (i = 0; i < num_pads; i++) {
226 strcpy (tmp, "%3D"); // replace '=' with '%3D'
229 return enc_urlencode;
236 * Builds an OIDC authorization code including
237 * a reclaim ticket and nonce
239 * @param issuer the issuer of the ticket, used to sign the ticket and nonce
240 * @param ticket the ticket to include in the code
241 * @param attrs list of attributes whicha re shared
242 * @param nonce the nonce to include in the code
243 * @return a new authorization code (caller must free)
246 OIDC_build_authz_code (const struct GNUNET_CRYPTO_EcdsaPrivateKey *issuer,
247 const struct GNUNET_RECLAIM_Ticket *ticket,
248 struct GNUNET_RECLAIM_ATTRIBUTE_ClaimList *attrs,
249 const char *nonce_str)
255 size_t signature_payload_len;
256 size_t attr_list_len;
257 size_t code_payload_len;
259 unsigned int nonce_tmp;
260 struct GNUNET_CRYPTO_EcdsaSignature signature;
261 struct GNUNET_CRYPTO_EccSignaturePurpose *purpose;
264 signature_payload_len =
265 sizeof (struct GNUNET_RECLAIM_Ticket) + sizeof (unsigned int);
268 attr_list_len = GNUNET_RECLAIM_ATTRIBUTE_list_serialize_get_size (attrs);
269 signature_payload_len += attr_list_len;
270 attrs_ser = GNUNET_malloc (attr_list_len);
271 GNUNET_RECLAIM_ATTRIBUTE_list_serialize (attrs, attrs_ser);
273 code_payload_len = sizeof (struct GNUNET_CRYPTO_EccSignaturePurpose) +
274 signature_payload_len + sizeof (signature);
275 code_payload = GNUNET_malloc (code_payload_len);
276 purpose = (struct GNUNET_CRYPTO_EccSignaturePurpose *) code_payload;
277 purpose->size = htonl (sizeof (struct GNUNET_CRYPTO_EccSignaturePurpose) +
278 signature_payload_len);
279 purpose->purpose = htonl (GNUNET_SIGNATURE_PURPOSE_RECLAIM_CODE_SIGN);
280 // First, copy ticket
281 buf_ptr = (char *) &purpose[1];
282 memcpy (buf_ptr, ticket, sizeof (struct GNUNET_RECLAIM_Ticket));
283 buf_ptr += sizeof (struct GNUNET_RECLAIM_Ticket);
286 if (NULL != nonce_str)
288 if ((1 != SSCANF (nonce_str, "%u", &nonce)) || (nonce > UINT16_MAX))
290 GNUNET_free (code_payload);
291 GNUNET_free_non_null (attrs_ser);
295 nonce_tmp = htons (nonce);
296 memcpy (buf_ptr, &nonce_tmp, sizeof (unsigned int));
297 buf_ptr += sizeof (unsigned int);
298 // Finally, attributes
299 if (NULL != attrs_ser)
301 memcpy (buf_ptr, attrs_ser, attr_list_len);
302 buf_ptr += attr_list_len;
304 if (GNUNET_SYSERR == GNUNET_CRYPTO_ecdsa_sign (issuer, purpose, &signature))
306 GNUNET_free (code_payload);
307 GNUNET_free_non_null (attrs_ser);
310 memcpy (buf_ptr, &signature, sizeof (signature));
311 code_str = base64_encode ((const char *) &code_payload,
313 GNUNET_free (code_payload);
314 GNUNET_free_non_null (attrs_ser);
320 * Parse reclaim ticket and nonce from
321 * authorization code.
322 * This also verifies the signature in the code.
324 * @param audience the expected audience of the code
325 * @param code the string representation of the code
326 * @param ticket where to store the ticket
327 * @param attrs the attributes in the code
328 * @param nonce where to store the nonce
329 * @return GNUNET_OK if successful, else GNUNET_SYSERR
332 OIDC_parse_authz_code (const struct GNUNET_CRYPTO_EcdsaPublicKey *audience,
334 struct GNUNET_RECLAIM_Ticket *ticket,
335 struct GNUNET_RECLAIM_ATTRIBUTE_ClaimList **attrs,
341 struct GNUNET_CRYPTO_EccSignaturePurpose *purpose;
342 struct GNUNET_CRYPTO_EcdsaSignature *signature;
343 size_t code_payload_len;
344 size_t attrs_ser_len;
345 size_t signature_offset;
350 GNUNET_STRINGS_base64_decode (code, strlen (code), (void **) &code_payload);
351 purpose = (struct GNUNET_CRYPTO_EccSignaturePurpose *) code_payload;
352 attrs_ser_len = code_payload_len;
353 attrs_ser_len -= sizeof (struct GNUNET_CRYPTO_EccSignaturePurpose);
354 *ticket = *((struct GNUNET_RECLAIM_Ticket*) &purpose[1]);
355 attrs_ser_len -= sizeof (struct GNUNET_RECLAIM_Ticket);
356 nonce = ntohs (((unsigned int *) &ticket[1]));
357 attrs_ser_len -= sizeof (unsigned int);
360 code_payload_len - sizeof (struct GNUNET_CRYPTO_EcdsaSignature);
361 signature = (struct GNUNET_CRYPTO_EcdsaSignature *)&ptr[signature_offset];
362 attrs_ser_len -= sizeof (struct GNUNET_CRYPTO_EcdsaSignature);
363 attrs_ser = ((char *) &ticket[1]) + sizeof (unsigned int);
364 *attrs = GNUNET_RECLAIM_ATTRIBUTE_list_deserialize (attrs_ser, attrs_ser_len);
365 if (0 != GNUNET_memcmp (audience, &ticket->audience))
367 GNUNET_RECLAIM_ATTRIBUTE_list_destroy (*attrs);
368 GNUNET_free (code_payload);
369 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
370 "Audience in ticket does not match client!\n");
371 return GNUNET_SYSERR;
374 GNUNET_CRYPTO_ecdsa_verify (GNUNET_SIGNATURE_PURPOSE_RECLAIM_CODE_SIGN,
379 GNUNET_RECLAIM_ATTRIBUTE_list_destroy (*attrs);
380 GNUNET_free (code_payload);
381 GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Signature of AuthZ code invalid!\n");
382 return GNUNET_SYSERR;
386 GNUNET_asprintf (nonce_str, "%u", nonce);
392 * Build a token response for a token request
393 * TODO: Maybe we should add the scope here?
395 * @param access_token the access token to include
396 * @param id_token the id_token to include
397 * @param expiration_time the expiration time of the token(s)
398 * @param token_response where to store the response
401 OIDC_build_token_response (const char *access_token,
402 const char *id_token,
403 const struct GNUNET_TIME_Relative *expiration_time,
404 char **token_response)
408 root_json = json_object ();
410 GNUNET_assert (NULL != access_token);
411 GNUNET_assert (NULL != id_token);
412 GNUNET_assert (NULL != expiration_time);
413 json_object_set_new (root_json, "access_token", json_string (access_token));
414 json_object_set_new (root_json, "token_type", json_string ("Bearer"));
415 json_object_set_new (
418 json_integer (expiration_time->rel_value_us / (1000 * 1000)));
419 json_object_set_new (root_json, "id_token", json_string (id_token));
420 *token_response = json_dumps (root_json, JSON_INDENT (0) | JSON_COMPACT);
421 json_decref (root_json);
425 * Generate a new access token
428 OIDC_access_token_new ()
430 char *access_token_number;
432 uint64_t random_number;
435 GNUNET_CRYPTO_random_u64 (GNUNET_CRYPTO_QUALITY_NONCE, UINT64_MAX);
436 GNUNET_asprintf (&access_token_number, "%" PRIu64, random_number);
437 GNUNET_STRINGS_base64_encode (access_token_number,
438 strlen (access_token_number),