gracely handle missing PKCE params in token request

src/reclaim/oidc_helper.c

@@ -31,7 +31,7 @@
 #include "gnunet_reclaim_service.h"
 #include "gnunet_signatures.h"
 #include "oidc_helper.h"
-//#include "benchmark.h"
+// #include "benchmark.h"
 #include <gcrypt.h>
 
 GNUNET_NETWORK_STRUCT_BEGIN
@@ -39,7 +39,8 @@ GNUNET_NETWORK_STRUCT_BEGIN
 /**
  * The signature used to generate the authorization code
  */
-struct OIDC_Parameters {
+struct OIDC_Parameters
+{
   /**
    * The reclaim ticket
    */
@@ -64,41 +65,41 @@ struct OIDC_Parameters {
 GNUNET_NETWORK_STRUCT_END
 
 static char *
-create_jwt_header(void)
+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));
+  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(0) | JSON_COMPACT);
-  json_decref(root);
+  json_str = json_dumps (root, JSON_INDENT (0) | JSON_COMPACT);
+  json_decref (root);
   return json_str;
 }
 
 static void
-replace_char(char *str, char find, char replace)
+replace_char (char *str, char find, char replace)
 {
-  char *current_pos = strchr(str, find);
+  char *current_pos = strchr (str, find);
 
   while (current_pos)
-    {
-      *current_pos = replace;
-      current_pos = strchr(current_pos, find);
-    }
+  {
+    *current_pos = replace;
+    current_pos = strchr (current_pos, find);
+  }
 }
 
 // RFC4648
 static void
-fix_base64(char *str)
+fix_base64 (char *str)
 {
   // Replace + with -
-  replace_char(str, '+', '-');
+  replace_char (str, '+', '-');
 
   // Replace / with _
-  replace_char(str, '/', '_');
+  replace_char (str, '/', '_');
 }
 
 /**
@@ -112,12 +113,12 @@ fix_base64(char *str)
  * @return a new base64-encoded JWT string.
  */
 char *
-OIDC_id_token_new(const struct GNUNET_CRYPTO_EcdsaPublicKey *aud_key,
-                  const struct GNUNET_CRYPTO_EcdsaPublicKey *sub_key,
-                  const struct GNUNET_RECLAIM_ATTRIBUTE_ClaimList *attrs,
-                  const struct GNUNET_TIME_Relative *expiration_time,
-                  const char *nonce,
-                  const char *secret_key)
+OIDC_id_token_new (const struct GNUNET_CRYPTO_EcdsaPublicKey *aud_key,
+                   const struct GNUNET_CRYPTO_EcdsaPublicKey *sub_key,
+                   const struct GNUNET_RECLAIM_ATTRIBUTE_ClaimList *attrs,
+                   const struct GNUNET_TIME_Relative *expiration_time,
+                   const char *nonce,
+                   const char *secret_key)
 {
   struct GNUNET_RECLAIM_ATTRIBUTE_ClaimListEntry *le;
   struct GNUNET_HashCode signature;
@@ -136,108 +137,108 @@ OIDC_id_token_new(const struct GNUNET_CRYPTO_EcdsaPublicKey *aud_key,
   json_t *body;
 
   // iat REQUIRED time now
-  time_now = GNUNET_TIME_absolute_get();
+  time_now = GNUNET_TIME_absolute_get ();
   // exp REQUIRED time expired from config
-  exp_time = GNUNET_TIME_absolute_add(time_now, *expiration_time);
+  exp_time = GNUNET_TIME_absolute_add (time_now, *expiration_time);
   // auth_time only if max_age
   // nonce only if nonce
   // OPTIONAL acr,amr,azp
   subject =
-    GNUNET_STRINGS_data_to_string_alloc(sub_key,
-                                        sizeof(struct
-                                               GNUNET_CRYPTO_EcdsaPublicKey));
+    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();
+    GNUNET_STRINGS_data_to_string_alloc (aud_key,
+                                         sizeof(struct
+                                                GNUNET_CRYPTO_EcdsaPublicKey));
+  header = create_jwt_header ();
+  body = json_object ();
 
   // iss REQUIRED case sensitive server uri with https
   // The issuer is the local reclaim instance (e.g.
   // https://reclaim.id/api/openid)
-  json_object_set_new(body, "iss", json_string(SERVER_ADDRESS));
+  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));
+  json_object_set_new (body, "sub", json_string (subject));
   // aud REQUIRED public key client_id must be there
-  json_object_set_new(body, "aud", json_string(audience));
+  json_object_set_new (body, "aud", json_string (audience));
   // iat
-  json_object_set_new(body,
-                      "iat",
-                      json_integer(time_now.abs_value_us / (1000 * 1000)));
+  json_object_set_new (body,
+                       "iat",
+                       json_integer (time_now.abs_value_us / (1000 * 1000)));
   // exp
-  json_object_set_new(body,
-                      "exp",
-                      json_integer(exp_time.abs_value_us / (1000 * 1000)));
+  json_object_set_new (body,
+                       "exp",
+                       json_integer (exp_time.abs_value_us / (1000 * 1000)));
   // nbf
-  json_object_set_new(body,
-                      "nbf",
-                      json_integer(time_now.abs_value_us / (1000 * 1000)));
+  json_object_set_new (body,
+                       "nbf",
+                       json_integer (time_now.abs_value_us / (1000 * 1000)));
   // nonce
   if (NULL != nonce)
-    json_object_set_new(body, "nonce", json_string(nonce));
+    json_object_set_new (body, "nonce", json_string (nonce));
 
   for (le = attrs->list_head; NULL != le; le = le->next)
-    {
-      attr_val_str =
-        GNUNET_RECLAIM_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_COMPACT);
-  json_decref(body);
-
-  GNUNET_STRINGS_base64_encode(header, strlen(header), &header_base64);
-  fix_base64(header_base64);
-
-  GNUNET_STRINGS_base64_encode(body_str, strlen(body_str), &body_base64);
-  fix_base64(body_base64);
-
-  GNUNET_free(subject);
-  GNUNET_free(audience);
+  {
+    attr_val_str =
+      GNUNET_RECLAIM_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_COMPACT);
+  json_decref (body);
+
+  GNUNET_STRINGS_base64_encode (header, strlen (header), &header_base64);
+  fix_base64 (header_base64);
+
+  GNUNET_STRINGS_base64_encode (body_str, strlen (body_str), &body_base64);
+  fix_base64 (body_base64);
+
+  GNUNET_free (subject);
+  GNUNET_free (audience);
 
   /**
    * Creating the JWT signature. This might not be
    * standards compliant, check.
    */
-  GNUNET_asprintf(&signature_target, "%s.%s", header_base64, body_base64);
-  GNUNET_CRYPTO_hmac_raw(secret_key,
-                         strlen(secret_key),
-                         signature_target,
-                         strlen(signature_target),
-                         &signature);
-  GNUNET_STRINGS_base64_encode((const char *)&signature,
-                               sizeof(struct GNUNET_HashCode),
-                               &signature_base64);
-  fix_base64(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_asprintf (&signature_target, "%s.%s", header_base64, body_base64);
+  GNUNET_CRYPTO_hmac_raw (secret_key,
+                          strlen (secret_key),
+                          signature_target,
+                          strlen (signature_target),
+                          &signature);
+  GNUNET_STRINGS_base64_encode ((const char *) &signature,
+                                sizeof(struct GNUNET_HashCode),
+                                &signature_base64);
+  fix_base64 (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);
   return result;
 }
 
 /* Converts a hex character to its integer value */
 static char
-from_hex(char ch)
+from_hex (char ch)
 {
-  return isdigit(ch) ? ch - '0' : tolower(ch) - 'a' + 10;
+  return isdigit (ch) ? ch - '0' : tolower (ch) - 'a' + 10;
 }
 
 /* Converts an integer value to its hex character*/
 static char
-to_hex(char code)
+to_hex (char code)
 {
   static char hex[] = "0123456789abcdef";
 
@@ -247,27 +248,27 @@ to_hex(char code)
 /* Returns a url-encoded version of str */
 /* IMPORTANT: be sure to free() the returned string after use */
 static char *
-url_encode(const char *str)
+url_encode (const char *str)
 {
-  char *pstr = (char *)str;
-  char *buf = GNUNET_malloc(strlen(str) * 3 + 1);
+  char *pstr = (char *) str;
+  char *buf = GNUNET_malloc (strlen (str) * 3 + 1);
   char *pbuf = buf;
 
   while (*pstr)
+  {
+    if (isalnum (*pstr) || (*pstr == '-') || (*pstr == '_') || (*pstr == '.') ||
+        (*pstr == '~') )
+      *pbuf++ = *pstr;
+    else if (*pstr == ' ')
+      *pbuf++ = '+';
+    else
     {
-      if (isalnum(*pstr) || *pstr == '-' || *pstr == '_' || *pstr == '.' ||
-          *pstr == '~')
-        *pbuf++ = *pstr;
-      else if (*pstr == ' ')
-        *pbuf++ = '+';
-      else
-        {
-          *pbuf++ = '%';
-          *pbuf++ = to_hex(*pstr >> 4);
-          *pbuf++ = to_hex(*pstr & 15);
-        }
-      pstr++;
+      *pbuf++ = '%';
+      *pbuf++ = to_hex (*pstr >> 4);
+      *pbuf++ = to_hex (*pstr & 15);
     }
+    pstr++;
+  }
   *pbuf = '\0';
   return buf;
 }
@@ -276,32 +277,32 @@ url_encode(const char *str)
 /* Returns a url-decoded version of str */
 /* IMPORTANT: be sure to free() the returned string after use */
 static char *
-url_decode(const char *str)
+url_decode (const char *str)
 {
-  char *pstr = (char *)str;
-  char *buf = GNUNET_malloc(strlen(str) + 1);
+  char *pstr = (char *) str;
+  char *buf = GNUNET_malloc (strlen (str) + 1);
   char *pbuf = buf;
 
   while (*pstr)
+  {
+    if (*pstr == '%')
+    {
+      if (pstr[1] && pstr[2])
+      {
+        *pbuf++ = from_hex (pstr[1]) << 4 | from_hex (pstr[2]);
+        pstr += 2;
+      }
+    }
+    else if (*pstr == '+')
+    {
+      *pbuf++ = ' ';
+    }
+    else
     {
-      if (*pstr == '%')
-        {
-          if (pstr[1] && pstr[2])
-            {
-              *pbuf++ = from_hex(pstr[1]) << 4 | from_hex(pstr[2]);
-              pstr += 2;
-            }
-        }
-      else if (*pstr == '+')
-        {
-          *pbuf++ = ' ';
-        }
-      else
-        {
-          *pbuf++ = *pstr;
-        }
-      pstr++;
+      *pbuf++ = *pstr;
     }
+    pstr++;
+  }
   *pbuf = '\0';
   return buf;
 }
@@ -313,14 +314,14 @@ url_decode(const char *str)
  * @return base64 encoded string
  */
 static char *
-base64_and_urlencode(const char *data, size_t data_size)
+base64_and_urlencode (const char *data, size_t data_size)
 {
   char *enc;
   char *urlenc;
 
-  GNUNET_STRINGS_base64_encode(data, data_size, &enc);
-  urlenc = url_encode(enc);
-  GNUNET_free(enc);
+  GNUNET_STRINGS_base64_encode (data, data_size, &enc);
+  urlenc = url_encode (enc);
+  GNUNET_free (enc);
   return urlenc;
 }
 
@@ -332,111 +333,111 @@ base64_and_urlencode(const char *data, size_t data_size)
  * @return base64 encoded string
  */
 static char *
-base64url_encode(const char *data, size_t data_size)
+base64url_encode (const char *data, size_t data_size)
 {
   char *enc;
   size_t pos;
 
-  GNUNET_STRINGS_base64_encode(data, data_size, &enc);
-  //Replace with correct characters for base64url
+  GNUNET_STRINGS_base64_encode (data, data_size, &enc);
+  // Replace with correct characters for base64url
   pos = 0;
   while ('\0' != enc[pos])
+  {
+    if ('+' == enc[pos])
+      enc[pos] = '-';
+    if ('/' == enc[pos])
+      enc[pos] = '_';
+    if ('=' == enc[pos])
     {
-      if ('+' == enc[pos])
-        enc[pos] = '-';
-      if ('/' == enc[pos])
-        enc[pos] = '_';
-      if ('=' == enc[pos])
-        {
-          enc[pos] = '\0';
-          break;
-        }
-      pos++;
+      enc[pos] = '\0';
+      break;
     }
+    pos++;
+  }
   return enc;
 }
 
 
 static void
-derive_aes_key(struct GNUNET_CRYPTO_SymmetricSessionKey *key,
-               struct GNUNET_CRYPTO_SymmetricInitializationVector *iv,
-               struct GNUNET_HashCode *key_material)
+derive_aes_key (struct GNUNET_CRYPTO_SymmetricSessionKey *key,
+                struct GNUNET_CRYPTO_SymmetricInitializationVector *iv,
+                struct GNUNET_HashCode *key_material)
 {
   static const char ctx_key[] = "reclaim-aes-ctx-key";
   static const char ctx_iv[] = "reclaim-aes-ctx-iv";
 
-  GNUNET_CRYPTO_kdf(key,
-                    sizeof(struct GNUNET_CRYPTO_SymmetricSessionKey),
-                    ctx_key,
-                    strlen(ctx_key),
-                    key_material,
-                    sizeof(struct GNUNET_HashCode),
-                    NULL);
-  GNUNET_CRYPTO_kdf(iv,
-                    sizeof(
-                      struct GNUNET_CRYPTO_SymmetricInitializationVector),
-                    ctx_iv,
-                    strlen(ctx_iv),
-                    key_material,
-                    sizeof(struct GNUNET_HashCode),
-                    NULL);
+  GNUNET_CRYPTO_kdf (key,
+                     sizeof(struct GNUNET_CRYPTO_SymmetricSessionKey),
+                     ctx_key,
+                     strlen (ctx_key),
+                     key_material,
+                     sizeof(struct GNUNET_HashCode),
+                     NULL);
+  GNUNET_CRYPTO_kdf (iv,
+                     sizeof(
+                       struct GNUNET_CRYPTO_SymmetricInitializationVector),
+                     ctx_iv,
+                     strlen (ctx_iv),
+                     key_material,
+                     sizeof(struct GNUNET_HashCode),
+                     NULL);
 }
 
 
 static void
-calculate_key_priv(struct GNUNET_CRYPTO_SymmetricSessionKey *key,
-                   struct GNUNET_CRYPTO_SymmetricInitializationVector *iv,
-                   const struct GNUNET_CRYPTO_EcdsaPrivateKey *ecdsa_priv,
-                   const struct GNUNET_CRYPTO_EcdhePublicKey *ecdh_pub)
+calculate_key_priv (struct GNUNET_CRYPTO_SymmetricSessionKey *key,
+                    struct GNUNET_CRYPTO_SymmetricInitializationVector *iv,
+                    const struct GNUNET_CRYPTO_EcdsaPrivateKey *ecdsa_priv,
+                    const struct GNUNET_CRYPTO_EcdhePublicKey *ecdh_pub)
 {
   struct GNUNET_HashCode key_material;
 
-  GNUNET_CRYPTO_ecdsa_ecdh(ecdsa_priv, ecdh_pub, &key_material);
-  derive_aes_key(key, iv, &key_material);
+  GNUNET_CRYPTO_ecdsa_ecdh (ecdsa_priv, ecdh_pub, &key_material);
+  derive_aes_key (key, iv, &key_material);
 }
 
 
 static void
-calculate_key_pub(struct GNUNET_CRYPTO_SymmetricSessionKey *key,
-                  struct GNUNET_CRYPTO_SymmetricInitializationVector *iv,
-                  const struct GNUNET_CRYPTO_EcdsaPublicKey *ecdsa_pub,
-                  const struct GNUNET_CRYPTO_EcdhePrivateKey *ecdh_priv)
+calculate_key_pub (struct GNUNET_CRYPTO_SymmetricSessionKey *key,
+                   struct GNUNET_CRYPTO_SymmetricInitializationVector *iv,
+                   const struct GNUNET_CRYPTO_EcdsaPublicKey *ecdsa_pub,
+                   const struct GNUNET_CRYPTO_EcdhePrivateKey *ecdh_priv)
 {
   struct GNUNET_HashCode key_material;
 
-  GNUNET_CRYPTO_ecdh_ecdsa(ecdh_priv, ecdsa_pub, &key_material);
-  derive_aes_key(key, iv, &key_material);
+  GNUNET_CRYPTO_ecdh_ecdsa (ecdh_priv, ecdsa_pub, &key_material);
+  derive_aes_key (key, iv, &key_material);
 }
 
 
 static void
-decrypt_payload(const struct GNUNET_CRYPTO_EcdsaPrivateKey *ecdsa_priv,
-                const struct GNUNET_CRYPTO_EcdhePublicKey *ecdh_pub,
-                const char *ct,
-                size_t ct_len,
-                char *buf)
+decrypt_payload (const struct GNUNET_CRYPTO_EcdsaPrivateKey *ecdsa_priv,
+                 const struct GNUNET_CRYPTO_EcdhePublicKey *ecdh_pub,
+                 const char *ct,
+                 size_t ct_len,
+                 char *buf)
 {
   struct GNUNET_CRYPTO_SymmetricSessionKey key;
   struct GNUNET_CRYPTO_SymmetricInitializationVector iv;
 
-  calculate_key_priv(&key, &iv, ecdsa_priv, ecdh_pub);
-  GNUNET_break(GNUNET_CRYPTO_symmetric_decrypt(ct, ct_len, &key, &iv, buf));
+  calculate_key_priv (&key, &iv, ecdsa_priv, ecdh_pub);
+  GNUNET_break (GNUNET_CRYPTO_symmetric_decrypt (ct, ct_len, &key, &iv, buf));
 }
 
 
 static void
-encrypt_payload(const struct GNUNET_CRYPTO_EcdsaPublicKey *ecdsa_pub,
-                const struct GNUNET_CRYPTO_EcdhePrivateKey *ecdh_priv,
-                const char *payload,
-                size_t payload_len,
-                char *buf)
+encrypt_payload (const struct GNUNET_CRYPTO_EcdsaPublicKey *ecdsa_pub,
+                 const struct GNUNET_CRYPTO_EcdhePrivateKey *ecdh_priv,
+                 const char *payload,
+                 size_t payload_len,
+                 char *buf)
 {
   struct GNUNET_CRYPTO_SymmetricSessionKey key;
   struct GNUNET_CRYPTO_SymmetricInitializationVector iv;
 
-  calculate_key_pub(&key, &iv, ecdsa_pub, ecdh_priv);
-  GNUNET_break(
-    GNUNET_CRYPTO_symmetric_encrypt(payload, payload_len, &key, &iv, buf));
+  calculate_key_pub (&key, &iv, ecdsa_pub, ecdh_priv);
+  GNUNET_break (
+    GNUNET_CRYPTO_symmetric_encrypt (payload, payload_len, &key, &iv, buf));
 }
 
 /**
@@ -451,11 +452,11 @@ encrypt_payload(const struct GNUNET_CRYPTO_EcdsaPublicKey *ecdsa_pub,
  * @return a new authorization code (caller must free)
  */
 char *
-OIDC_build_authz_code(const struct GNUNET_CRYPTO_EcdsaPrivateKey *issuer,
-                      const struct GNUNET_RECLAIM_Ticket *ticket,
-                      struct GNUNET_RECLAIM_ATTRIBUTE_ClaimList *attrs,
-                      const char *nonce_str,
-                      const char *code_challenge)
+OIDC_build_authz_code (const struct GNUNET_CRYPTO_EcdsaPrivateKey *issuer,
+                       const struct GNUNET_RECLAIM_Ticket *ticket,
+                       struct GNUNET_RECLAIM_ATTRIBUTE_ClaimList *attrs,
+                       const char *nonce_str,
+                       const char *code_challenge)
 {
   struct OIDC_Parameters params;
   char *code_payload;
@@ -475,98 +476,99 @@ OIDC_build_authz_code(const struct GNUNET_CRYPTO_EcdsaPrivateKey *issuer,
 
   /** PLAINTEXT **/
   // Assign ticket
-  memset(&params, 0, sizeof(params));
+  memset (&params, 0, sizeof(params));
   params.ticket = *ticket;
   // Assign nonce
   nonce = 0;
   payload_len = sizeof(struct OIDC_Parameters);
-  if (NULL != nonce_str && strcmp("", nonce_str) != 0)
+  if ((NULL != nonce_str)&& (strcmp ("", nonce_str) != 0))
+  {
+    if ((1 != sscanf (nonce_str, "%u", &nonce)) || (nonce > UINT32_MAX))
     {
-      if ((1 != sscanf(nonce_str, "%u", &nonce)) || (nonce > UINT32_MAX))
-        {
-          GNUNET_break(0);
-          GNUNET_log(GNUNET_ERROR_TYPE_ERROR, "Invalid nonce %s\n", nonce_str);
-          return NULL;
-        }
-      GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
-                 "Got nonce: %u from %s\n",
-                 nonce,
-                 nonce_str);
+      GNUNET_break (0);
+      GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Invalid nonce %s\n", nonce_str);
+      return NULL;
     }
-  nonce_tmp = htonl(nonce);
+    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                "Got nonce: %u from %s\n",
+                nonce,
+                nonce_str);
+  }
+  nonce_tmp = htonl (nonce);
   params.nonce = nonce_tmp;
   // Assign code challenge
   if (NULL != code_challenge)
-    code_challenge_len = strlen(code_challenge);
+    code_challenge_len = strlen (code_challenge);
   payload_len += code_challenge_len;
-  params.code_challenge_len = htonl(code_challenge_len);
+  params.code_challenge_len = htonl (code_challenge_len);
   // Assign attributes
   if (NULL != attrs)
-    {
-      // Get length
-      attr_list_len = GNUNET_RECLAIM_ATTRIBUTE_list_serialize_get_size(attrs);
-      params.attr_list_len = htonl(attr_list_len);
-      GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
-                 "Length of serialized attributes: %lu\n",
-                 attr_list_len);
-      // Get serialized attributes
-      payload_len += attr_list_len;
-    }
+  {
+    // Get length
+    attr_list_len = GNUNET_RECLAIM_ATTRIBUTE_list_serialize_get_size (attrs);
+    params.attr_list_len = htonl (attr_list_len);
+    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                "Length of serialized attributes: %lu\n",
+                attr_list_len);
+    // Get serialized attributes
+    payload_len += attr_list_len;
+  }
   // Get plaintext length
-  payload = GNUNET_malloc(payload_len);
-  memcpy(payload, &params, sizeof(params));
+  payload = GNUNET_malloc (payload_len);
+  memcpy (payload, &params, sizeof(params));
   tmp = payload + sizeof(params);
   if (0 < code_challenge_len)
-    {
-      memcpy(tmp, code_challenge, code_challenge_len);
-      tmp += code_challenge_len;
-    }
+  {
+    memcpy (tmp, code_challenge, code_challenge_len);
+    tmp += code_challenge_len;
+  }
   if (0 < attr_list_len)
-    GNUNET_RECLAIM_ATTRIBUTE_list_serialize(attrs, tmp);
+    GNUNET_RECLAIM_ATTRIBUTE_list_serialize (attrs, tmp);
   /** END **/
 
   /** ENCRYPT **/
   // Get length
-  code_payload_len = sizeof(struct GNUNET_CRYPTO_EccSignaturePurpose) +
-                     sizeof(struct GNUNET_CRYPTO_EcdhePublicKey) +
-                     payload_len + sizeof(struct GNUNET_CRYPTO_EcdsaSignature);
-  GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
-             "Length of data to encode: %lu\n",
-             code_payload_len);
+  code_payload_len = sizeof(struct GNUNET_CRYPTO_EccSignaturePurpose)
+                     + sizeof(struct GNUNET_CRYPTO_EcdhePublicKey)
+                     + payload_len + sizeof(struct
+                                            GNUNET_CRYPTO_EcdsaSignature);
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Length of data to encode: %lu\n",
+              code_payload_len);
 
   // Generate ECDH key
-  ecdh_priv = GNUNET_CRYPTO_ecdhe_key_create();
-  GNUNET_CRYPTO_ecdhe_key_get_public(ecdh_priv, &ecdh_pub);
+  ecdh_priv = GNUNET_CRYPTO_ecdhe_key_create ();
+  GNUNET_CRYPTO_ecdhe_key_get_public (ecdh_priv, &ecdh_pub);
   // Initialize code payload
-  code_payload = GNUNET_malloc(code_payload_len);
-  GNUNET_assert(NULL != code_payload);
-  purpose = (struct GNUNET_CRYPTO_EccSignaturePurpose *)code_payload;
-  purpose->size = htonl(sizeof(struct GNUNET_CRYPTO_EccSignaturePurpose) +
-                        sizeof(ecdh_pub) + payload_len);
-  purpose->purpose = htonl(GNUNET_SIGNATURE_PURPOSE_RECLAIM_CODE_SIGN);
+  code_payload = GNUNET_malloc (code_payload_len);
+  GNUNET_assert (NULL != code_payload);
+  purpose = (struct GNUNET_CRYPTO_EccSignaturePurpose *) code_payload;
+  purpose->size = htonl (sizeof(struct GNUNET_CRYPTO_EccSignaturePurpose)
+                         + sizeof(ecdh_pub) + payload_len);
+  purpose->purpose = htonl (GNUNET_SIGNATURE_PURPOSE_RECLAIM_CODE_SIGN);
   // Store pubkey
-  buf_ptr = (char *)&purpose[1];
-  memcpy(buf_ptr, &ecdh_pub, sizeof(ecdh_pub));
+  buf_ptr = (char *) &purpose[1];
+  memcpy (buf_ptr, &ecdh_pub, sizeof(ecdh_pub));
   buf_ptr += sizeof(ecdh_pub);
   // Encrypt plaintext and store
-  encrypt_payload(&ticket->audience, ecdh_priv, payload, payload_len, buf_ptr);
-  GNUNET_free(ecdh_priv);
-  GNUNET_free(payload);
+  encrypt_payload (&ticket->audience, ecdh_priv, payload, payload_len, buf_ptr);
+  GNUNET_free (ecdh_priv);
+  GNUNET_free (payload);
   buf_ptr += payload_len;
   // Sign and store signature
   if (GNUNET_SYSERR ==
-      GNUNET_CRYPTO_ecdsa_sign(issuer,
-                               purpose,
-                               (struct GNUNET_CRYPTO_EcdsaSignature *)
-                               buf_ptr))
-    {
-      GNUNET_break(0);
-      GNUNET_log(GNUNET_ERROR_TYPE_ERROR, "Unable to sign code\n");
-      GNUNET_free(code_payload);
-      return NULL;
-    }
-  code_str = base64_and_urlencode(code_payload, code_payload_len);
-  GNUNET_free(code_payload);
+      GNUNET_CRYPTO_ecdsa_sign (issuer,
+                                purpose,
+                                (struct GNUNET_CRYPTO_EcdsaSignature *)
+                                buf_ptr))
+  {
+    GNUNET_break (0);
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Unable to sign code\n");
+    GNUNET_free (code_payload);
+    return NULL;
+  }
+  code_str = base64_and_urlencode (code_payload, code_payload_len);
+  GNUNET_free (code_payload);
   return code_str;
 }
 
@@ -585,12 +587,12 @@ OIDC_build_authz_code(const struct GNUNET_CRYPTO_EcdsaPrivateKey *issuer,
  * @return GNUNET_OK if successful, else GNUNET_SYSERR
  */
 int
-OIDC_parse_authz_code(const struct GNUNET_CRYPTO_EcdsaPrivateKey *ecdsa_priv,
-                      const char *code,
-                      const char *code_verifier,
-                      struct GNUNET_RECLAIM_Ticket *ticket,
-                      struct GNUNET_RECLAIM_ATTRIBUTE_ClaimList **attrs,
-                      char **nonce_str)
+OIDC_parse_authz_code (const struct GNUNET_CRYPTO_EcdsaPrivateKey *ecdsa_priv,
+                       const char *code,
+                       const char *code_verifier,
+                       struct GNUNET_RECLAIM_Ticket *ticket,
+                       struct GNUNET_RECLAIM_ATTRIBUTE_ClaimList **attrs,
+                       char **nonce_str)
 {
   char *code_payload;
   char *ptr;
@@ -610,103 +612,110 @@ OIDC_parse_authz_code(const struct GNUNET_CRYPTO_EcdsaPrivateKey *ecdsa_priv,
   uint32_t nonce = 0;
   struct OIDC_Parameters *params;
 
-  GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Trying to decode `%s'\n", code);
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Trying to decode `%s'\n", code);
   code_payload = NULL;
   code_payload_len =
-    GNUNET_STRINGS_base64_decode(code, strlen(code), (void **)&code_payload);
-  if (code_payload_len < sizeof(struct GNUNET_CRYPTO_EccSignaturePurpose) +
-      sizeof(struct GNUNET_CRYPTO_EcdhePublicKey) +
-      sizeof(struct OIDC_Parameters) +
-      sizeof(struct GNUNET_CRYPTO_EcdsaSignature))
-    {
-      GNUNET_log(GNUNET_ERROR_TYPE_ERROR, "Authorization code malformed\n");
-      GNUNET_free_non_null(code_payload);
-      return GNUNET_SYSERR;
-    }
-
-  purpose = (struct GNUNET_CRYPTO_EccSignaturePurpose *)code_payload;
+    GNUNET_STRINGS_base64_decode (code, strlen (code), (void **) &code_payload);
+  if (code_payload_len < sizeof(struct GNUNET_CRYPTO_EccSignaturePurpose)
+      + sizeof(struct GNUNET_CRYPTO_EcdhePublicKey)
+      + sizeof(struct OIDC_Parameters)
+      + sizeof(struct GNUNET_CRYPTO_EcdsaSignature))
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Authorization code malformed\n");
+    GNUNET_free_non_null (code_payload);
+    return GNUNET_SYSERR;
+  }
+
+  purpose = (struct GNUNET_CRYPTO_EccSignaturePurpose *) code_payload;
   plaintext_len = code_payload_len;
   plaintext_len -= sizeof(struct GNUNET_CRYPTO_EccSignaturePurpose);
-  ptr = (char *)&purpose[1];
+  ptr = (char *) &purpose[1];
   // Public ECDH key
-  ecdh_pub = (struct GNUNET_CRYPTO_EcdhePublicKey *)ptr;
+  ecdh_pub = (struct GNUNET_CRYPTO_EcdhePublicKey *) ptr;
   ptr += sizeof(struct GNUNET_CRYPTO_EcdhePublicKey);
   plaintext_len -= sizeof(struct GNUNET_CRYPTO_EcdhePublicKey);
 
   // Decrypt ciphertext
   plaintext_len -= sizeof(struct GNUNET_CRYPTO_EcdsaSignature);
-  plaintext = GNUNET_malloc(plaintext_len);
-  decrypt_payload(ecdsa_priv, ecdh_pub, ptr, plaintext_len, plaintext);
-  //ptr = plaintext;
+  plaintext = GNUNET_malloc (plaintext_len);
+  decrypt_payload (ecdsa_priv, ecdh_pub, ptr, plaintext_len, plaintext);
+  // ptr = plaintext;
   ptr += plaintext_len;
-  signature = (struct GNUNET_CRYPTO_EcdsaSignature *)ptr;
-  params = (struct OIDC_Parameters *)plaintext;
+  signature = (struct GNUNET_CRYPTO_EcdsaSignature *) ptr;
+  params = (struct OIDC_Parameters *) plaintext;
 
   // cmp code_challenge code_verifier
-  code_challenge_len = ntohl(params->code_challenge_len);
+  code_challenge_len = ntohl (params->code_challenge_len);
   if (0 != code_challenge_len) /* Only check if this code requires a CV */
+  {
+    if (NULL == code_verifier)
     {
-      code_verifier_hash = GNUNET_malloc(256 / 8);
-      // hash code verifier
-      gcry_md_hash_buffer(GCRY_MD_SHA256,
-                          code_verifier_hash,
-                          code_verifier,
-                          strlen(code_verifier));
-      // encode code verifier
-      expected_code_challenge = base64url_encode(code_verifier_hash, 256 / 8);
-      code_challenge = (char *)&params[1];
-      GNUNET_free(code_verifier_hash);
-      if ((strlen(expected_code_challenge) != code_challenge_len) ||
-          (0 !=
-           strncmp(expected_code_challenge, code_challenge, code_challenge_len)))
-        {
-          GNUNET_log(GNUNET_ERROR_TYPE_ERROR,
-                     "Invalid code verifier! Expected: %s, Got: %.*s\n",
-                     expected_code_challenge,
-                     code_challenge_len,
-                     code_challenge);
-          GNUNET_free_non_null(code_payload);
-          GNUNET_free(expected_code_challenge);
-          return GNUNET_SYSERR;
-        }
-      GNUNET_free(expected_code_challenge);
-    }
-  // Ticket
-  memcpy(ticket, &params->ticket, sizeof(params->ticket));
-  // Nonce
-  nonce = ntohl(params->nonce);  //ntohl (*((uint32_t *) ptr));
-  GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Got nonce: %u\n", nonce);
-  // Signature
-  GNUNET_CRYPTO_ecdsa_key_get_public(ecdsa_priv, &ecdsa_pub);
-  if (0 != GNUNET_memcmp(&ecdsa_pub, &ticket->audience))
-    {
-      GNUNET_free(code_payload);
-      GNUNET_free(plaintext);
-      GNUNET_log(GNUNET_ERROR_TYPE_ERROR,
-                 "Audience in ticket does not match client!\n");
+      GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                  "Expected code verifier!\n");
+      GNUNET_free_non_null (code_payload);
       return GNUNET_SYSERR;
     }
-  if (GNUNET_OK !=
-      GNUNET_CRYPTO_ecdsa_verify(GNUNET_SIGNATURE_PURPOSE_RECLAIM_CODE_SIGN,
-                                 purpose,
-                                 signature,
-                                 &ticket->identity))
+    code_verifier_hash = GNUNET_malloc (256 / 8);
+    // hash code verifier
+    gcry_md_hash_buffer (GCRY_MD_SHA256,
+                         code_verifier_hash,
+                         code_verifier,
+                         strlen (code_verifier));
+    // encode code verifier
+    expected_code_challenge = base64url_encode (code_verifier_hash, 256 / 8);
+    code_challenge = (char *) &params[1];
+    GNUNET_free (code_verifier_hash);
+    if ((strlen (expected_code_challenge) != code_challenge_len) ||
+        (0 !=
+         strncmp (expected_code_challenge, code_challenge, code_challenge_len)))
     {
-      GNUNET_free(code_payload);
-      GNUNET_free(plaintext);
-      GNUNET_log(GNUNET_ERROR_TYPE_ERROR, "Signature of AuthZ code invalid!\n");
+      GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                  "Invalid code verifier! Expected: %s, Got: %.*s\n",
+                  expected_code_challenge,
+                  code_challenge_len,
+                  code_challenge);
+      GNUNET_free_non_null (code_payload);
+      GNUNET_free (expected_code_challenge);
       return GNUNET_SYSERR;
     }
+    GNUNET_free (expected_code_challenge);
+  }
+  // Ticket
+  memcpy (ticket, &params->ticket, sizeof(params->ticket));
+  // Nonce
+  nonce = ntohl (params->nonce);  // ntohl (*((uint32_t *) ptr));
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Got nonce: %u\n", nonce);
+  // Signature
+  GNUNET_CRYPTO_ecdsa_key_get_public (ecdsa_priv, &ecdsa_pub);
+  if (0 != GNUNET_memcmp (&ecdsa_pub, &ticket->audience))
+  {
+    GNUNET_free (code_payload);
+    GNUNET_free (plaintext);
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                "Audience in ticket does not match client!\n");
+    return GNUNET_SYSERR;
+  }
+  if (GNUNET_OK !=
+      GNUNET_CRYPTO_ecdsa_verify (GNUNET_SIGNATURE_PURPOSE_RECLAIM_CODE_SIGN,
+                                  purpose,
+                                  signature,
+                                  &ticket->identity))
+  {
+    GNUNET_free (code_payload);
+    GNUNET_free (plaintext);
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Signature of AuthZ code invalid!\n");
+    return GNUNET_SYSERR;
+  }
   // Attributes
-  attrs_ser = ((char *)&params[1]) + code_challenge_len;
-  attrs_ser_len = ntohl(params->attr_list_len);
-  *attrs = GNUNET_RECLAIM_ATTRIBUTE_list_deserialize(attrs_ser, attrs_ser_len);
+  attrs_ser = ((char *) &params[1]) + code_challenge_len;
+  attrs_ser_len = ntohl (params->attr_list_len);
+  *attrs = GNUNET_RECLAIM_ATTRIBUTE_list_deserialize (attrs_ser, attrs_ser_len);
 
   *nonce_str = NULL;
   if (nonce != 0)
-    GNUNET_asprintf(nonce_str, "%u", nonce);
-  GNUNET_free(code_payload);
-  GNUNET_free(plaintext);
+    GNUNET_asprintf (nonce_str, "%u", nonce);
+  GNUNET_free (code_payload);
+  GNUNET_free (plaintext);
   return GNUNET_OK;
 }
 
@@ -721,42 +730,42 @@ OIDC_parse_authz_code(const struct GNUNET_CRYPTO_EcdsaPrivateKey *ecdsa_priv,
  * @param token_response where to store the response
  */
 void
-OIDC_build_token_response(const char *access_token,
-                          const char *id_token,
-                          const struct GNUNET_TIME_Relative *expiration_time,
-                          char **token_response)
+OIDC_build_token_response (const char *access_token,
+                           const char *id_token,
+                           const struct GNUNET_TIME_Relative *expiration_time,
+                           char **token_response)
 {
   json_t *root_json;
 
-  root_json = json_object();
-
-  GNUNET_assert(NULL != access_token);
-  GNUNET_assert(NULL != id_token);
-  GNUNET_assert(NULL != expiration_time);
-  json_object_set_new(root_json, "access_token", json_string(access_token));
-  json_object_set_new(root_json, "token_type", json_string("Bearer"));
-  json_object_set_new(root_json,
-                      "expires_in",
-                      json_integer(expiration_time->rel_value_us /
-                                   (1000 * 1000)));
-  json_object_set_new(root_json, "id_token", json_string(id_token));
-  *token_response = json_dumps(root_json, JSON_INDENT(0) | JSON_COMPACT);
-  json_decref(root_json);
+  root_json = json_object ();
+
+  GNUNET_assert (NULL != access_token);
+  GNUNET_assert (NULL != id_token);
+  GNUNET_assert (NULL != expiration_time);
+  json_object_set_new (root_json, "access_token", json_string (access_token));
+  json_object_set_new (root_json, "token_type", json_string ("Bearer"));
+  json_object_set_new (root_json,
+                       "expires_in",
+                       json_integer (expiration_time->rel_value_us
+                                     / (1000 * 1000)));
+  json_object_set_new (root_json, "id_token", json_string (id_token));
+  *token_response = json_dumps (root_json, JSON_INDENT (0) | JSON_COMPACT);
+  json_decref (root_json);
 }
 
 /**
  * Generate a new access token
  */
 char *
-OIDC_access_token_new()
+OIDC_access_token_new ()
 {
   char *access_token;
   uint64_t random_number;
 
   random_number =
-    GNUNET_CRYPTO_random_u64(GNUNET_CRYPTO_QUALITY_NONCE, UINT64_MAX);
-  GNUNET_STRINGS_base64_encode(&random_number,
-                               sizeof(uint64_t),
-                               &access_token);
+    GNUNET_CRYPTO_random_u64 (GNUNET_CRYPTO_QUALITY_NONCE, UINT64_MAX);
+  GNUNET_STRINGS_base64_encode (&random_number,
+                                sizeof(uint64_t),
+                                &access_token);
   return access_token;
 }