Source/charon/encoding/payloads/eap_payload.c

   1 /**
   2  * @file eap_payload.c
   3  *
   4  * @brief Implementation of eap_payload_t.
   5  *
   6  */
   7
   8 /*
   9  * Copyright (C) 2005 Jan Hutter, Martin Willi
  10  * Hochschule fuer Technik Rapperswil
  11  *
  12  * This program is free software; you can redistribute it and/or modify it
  13  * under the terms of the GNU General Public License as published by the
  14  * Free Software Foundation; either version 2 of the License, or (at your
  15  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
  16  *
  17  * This program is distributed in the hope that it will be useful, but
  18  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  19  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  20  * for more details.
  21  */
  22
  23 #include <stddef.h>
  24
  25 #include "eap_payload.h"
  26
  27
  28 typedef struct private_eap_payload_t private_eap_payload_t;
  29
  30 /**
  31  * Private data of an eap_payload_t object.
  32  *
  33  */
  34 struct private_eap_payload_t {
  35         /**
  36          * Public eap_payload_t interface.
  37          */
  38         eap_payload_t public;
  39
  40         /**
  41          * Next payload type.
  42          */
  43         u_int8_t  next_payload;
  44
  45         /**
  46          * Critical flag.
  47          */
  48         bool critical;
  49
  50         /**
  51          * Length of this payload.
  52          */
  53         u_int16_t payload_length;
  54
  55         /**
  56          * The contained message.
  57          */
  58         chunk_t message;
  59 };
  60
  61 /**
  62  * Encoding rules to parse or generate a EAP payload.
  63  *
  64  * The defined offsets are the positions in a object of type
  65  * private_eap_payload_t.
  66  *
  67  */
  68 encoding_rule_t eap_payload_encodings[] = {
  69         /* 1 Byte next payload type, stored in the field next_payload */
  70         { U_INT_8,                      offsetof(private_eap_payload_t, next_payload)   },
  71         /* the critical bit */
  72         { FLAG,                         offsetof(private_eap_payload_t, critical)               },
  73         /* 7 Bit reserved bits, nowhere stored */
  74         { RESERVED_BIT, 0                                                                                                       },
  75         { RESERVED_BIT, 0                                                                                                       },
  76         { RESERVED_BIT, 0                                                                                                       },
  77         { RESERVED_BIT, 0                                                                                                       },
  78         { RESERVED_BIT, 0                                                                                                       },
  79         { RESERVED_BIT, 0                                                                                                       },
  80         { RESERVED_BIT, 0                                                                                                       },
  81         /* Length of the whole payload*/
  82         { PAYLOAD_LENGTH,       offsetof(private_eap_payload_t, payload_length)},
  83         /* some eap data bytes, length is defined in PAYLOAD_LENGTH */
  84         { EAP_MESSAGE,          offsetof(private_eap_payload_t, message)                }
  85 };
  86
  87 /*
  88                            1                   2                   3
  89         0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
  90        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  91        ! Next Payload  !C!  RESERVED   !         Payload Length        !
  92        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  93        !                                                               !
  94        ~                       EAP Message                             ~
  95        !                                                               !
  96        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  97 */
  98
  99 /**
 100  * Implementation of payload_t.verify.
 101  */
 102 static status_t verify(private_eap_payload_t *this)
 103 {
 104         return SUCCESS;
 105 }
 106
 107 /**
 108  * Implementation of eap_payload_t.get_encoding_rules.
 109  */
 110 static void get_encoding_rules(private_eap_payload_t *this, encoding_rule_t **rules, size_t *rule_count)
 111 {
 112         *rules = eap_payload_encodings;
 113         *rule_count = sizeof(eap_payload_encodings) / sizeof(encoding_rule_t);
 114 }
 115
 116 /**
 117  * Implementation of payload_t.get_type.
 118  */
 119 static payload_type_t get_payload_type(private_eap_payload_t *this)
 120 {
 121         return EXTENSIBLE_AUTHENTICATION;
 122 }
 123
 124 /**
 125  * Implementation of payload_t.get_next_type.
 126  */
 127 static payload_type_t get_next_type(private_eap_payload_t *this)
 128 {
 129         return (this->next_payload);
 130 }
 131
 132 /**
 133  * Implementation of payload_t.set_next_type.
 134  */
 135 static void set_next_type(private_eap_payload_t *this,payload_type_t type)
 136 {
 137         this->next_payload = type;
 138 }
 139
 140 /**
 141  * Implementation of payload_t.get_length.
 142  */
 143 static size_t get_length(private_eap_payload_t *this)
 144 {
 145         return this->payload_length;
 146 }
 147
 148 /**
 149  * Implementation of eap_payload_t.set_message.
 150  */
 151 static void set_message (private_eap_payload_t *this, chunk_t message)
 152 {
 153         if (this->message.ptr != NULL)
 154         {
 155                 chunk_free(&(this->message));
 156         }
 157         this->message.ptr = clalloc(message.ptr,message.len);
 158         this->message.len = message.len;
 159         this->payload_length = EAP_PAYLOAD_HEADER_LENGTH + this->message.len;
 160 }
 161
 162 /**
 163  * Implementation of eap_payload_t.get_message.
 164  */
 165 static chunk_t get_message (private_eap_payload_t *this)
 166 {
 167         return (this->message);
 168 }
 169
 170 /**
 171  * Implementation of eap_payload_t.get_data_clone.
 172  */
 173 static chunk_t get_message_clone (private_eap_payload_t *this)
 174 {
 175         chunk_t cloned_message;
 176         if (this->message.ptr == NULL)
 177         {
 178                 return (this->message);
 179         }
 180         cloned_message.ptr = clalloc(this->message.ptr,this->message.len);
 181         cloned_message.len = this->message.len;
 182         return cloned_message;
 183 }
 184
 185 /**
 186  * Implementation of payload_t.destroy and eap_payload_t.destroy.
 187  */
 188 static void destroy(private_eap_payload_t *this)
 189 {
 190         if (this->message.ptr != NULL)
 191         {
 192                 chunk_free(&(this->message));
 193         }
 194
 195         free(this);
 196 }
 197
 198 /*
 199  * Described in header
 200  */
 201 eap_payload_t *eap_payload_create()
 202 {
 203         private_eap_payload_t *this = malloc_thing(private_eap_payload_t);
 204
 205         /* interface functions */
 206         this->public.payload_interface.verify = (status_t (*) (payload_t *))verify;
 207         this->public.payload_interface.get_encoding_rules = (void (*) (payload_t *, encoding_rule_t **, size_t *) ) get_encoding_rules;
 208         this->public.payload_interface.get_length = (size_t (*) (payload_t *)) get_length;
 209         this->public.payload_interface.get_next_type = (payload_type_t (*) (payload_t *)) get_next_type;
 210         this->public.payload_interface.set_next_type = (void (*) (payload_t *,payload_type_t)) set_next_type;
 211         this->public.payload_interface.get_type = (payload_type_t (*) (payload_t *)) get_payload_type;
 212         this->public.payload_interface.destroy = (void (*) (payload_t *))destroy;
 213
 214         /* public functions */
 215         this->public.destroy = (void (*) (eap_payload_t *)) destroy;
 216         this->public.set_message = (void (*) (eap_payload_t *,chunk_t)) set_message;
 217         this->public.get_message_clone = (chunk_t (*) (eap_payload_t *)) get_message_clone;
 218         this->public.get_message = (chunk_t (*) (eap_payload_t *)) get_message;
 219
 220         /* private variables */
 221         this->critical = FALSE;
 222         this->next_payload = NO_PAYLOAD;
 223         this->payload_length = EAP_PAYLOAD_HEADER_LENGTH;
 224         this->message = CHUNK_INITIALIZER;
 225
 226         return (&(this->public));
 227 }