Source/charon/payloads/nonce_payload.c

   1 /**
   2  * @file nonce_payload.h
   3  *
   4  * @brief Declaration of the class nonce_payload_t.
   5  *
   6  * An object of this type represents an IKEv2 Nonce-Payload.
   7  *
   8  */
   9
  10 /*
  11  * Copyright (C) 2005 Jan Hutter, Martin Willi
  12  * Hochschule fuer Technik Rapperswil
  13  *
  14  * This program is free software; you can redistribute it and/or modify it
  15  * under the terms of the GNU General Public License as published by the
  16  * Free Software Foundation; either version 2 of the License, or (at your
  17  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
  18  *
  19  * This program is distributed in the hope that it will be useful, but
  20  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  21  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  22  * for more details.
  23  */
  24
  25 /* offsetof macro */
  26 #include <stddef.h>
  27
  28 #include "nonce_payload.h"
  29
  30 #include "encodings.h"
  31 #include "../utils/allocator.h"
  32
  33
  34
  35 /**
  36  * Private data of an nonce_payload_t' Object
  37  *
  38  */
  39 typedef struct private_nonce_payload_s private_nonce_payload_t;
  40
  41 struct private_nonce_payload_s {
  42         /**
  43          * public nonce_payload_t interface
  44          */
  45         nonce_payload_t public;
  46
  47         /**
  48          * next payload type
  49          */
  50         u_int8_t  next_payload;
  51
  52         /**
  53          * Critical flag
  54          */
  55         bool critical;
  56
  57         /**
  58          * Length of this payload
  59          */
  60         u_int16_t payload_length;
  61
  62         /**
  63          * the contained nonce value
  64          */
  65         chunk_t nonce;
  66
  67         /**
  68          * @brief Computes the length of this payload.
  69          *
  70          * @param this  calling private_nonce_payload_t object
  71          * @return
  72          *                              SUCCESS in any case
  73          */
  74         status_t (*compute_length) (private_nonce_payload_t *this);
  75 };
  76
  77 /**
  78  * Encoding rules to parse or generate a nonce payload
  79  *
  80  * The defined offsets are the positions in a object of type
  81  * private_nonce_payload_t.
  82  *
  83  */
  84 encoding_rule_t nonce_payload_encodings[] = {
  85         /* 1 Byte next payload type, stored in the field next_payload */
  86         { U_INT_8,                      offsetof(private_nonce_payload_t, next_payload)         },
  87         /* the critical bit */
  88         { FLAG,                         offsetof(private_nonce_payload_t, critical)             },
  89         /* 7 Bit reserved bits, nowhere stored */
  90         { RESERVED_BIT, 0                                                                                                               },
  91         { RESERVED_BIT, 0                                                                                                               },
  92         { RESERVED_BIT, 0                                                                                                               },
  93         { RESERVED_BIT, 0                                                                                                               },
  94         { RESERVED_BIT, 0                                                                                                               },
  95         { RESERVED_BIT, 0                                                                                                               },
  96         { RESERVED_BIT, 0                                                                                                               },
  97         /* Length of the whole nonce payload*/
  98         { PAYLOAD_LENGTH,       offsetof(private_nonce_payload_t, payload_length)       },
  99         /* some nonce bytes, lenth is defined in PAYLOAD_LENGTH */
 100         { NONCE_DATA,                   offsetof(private_nonce_payload_t, nonce)                }
 101 };
 102
 103 /**
 104  * length of a nonce payload without a nonce in int
 105  */
 106 #define NONCE_PAYLOAD_HEADER_LENGTH 4
 107
 108 /**
 109  * Implements payload_t's and nonce_payload_t's destroy function.
 110  * See #payload_s.destroy or nonce_payload_s.destroy for description.
 111  */
 112 static status_t destroy(private_nonce_payload_t *this)
 113 {
 114         if (this->nonce.ptr)
 115         {
 116                 allocator_free(this->nonce.ptr);
 117         }
 118         allocator_free(this);
 119
 120         return SUCCESS;
 121 }
 122
 123 /**
 124  * Implements nonce_payload_t's set_nonce function.
 125  * See #nonce_payload_t.set_nonce for description.
 126  */
 127 static status_t set_nonce(private_nonce_payload_t *this, chunk_t nonce)
 128 {
 129         if (nonce.len >= 16 && nonce.len <= 256)
 130         {
 131                 this->nonce.len = nonce.len;
 132                 this->nonce.ptr = allocator_clone_bytes(nonce.ptr, nonce.len);
 133                 if (this->nonce.ptr == NULL)
 134                 {
 135                         return OUT_OF_RES;
 136                 }
 137                 this->payload_length = NONCE_PAYLOAD_HEADER_LENGTH + nonce.len;
 138                 return SUCCESS;
 139         }
 140         return INVALID_ARG;
 141 }
 142
 143 /**
 144  * Implements nonce_payload_t's get_nonce function.
 145  * See #nonce_payload_t.get_nonce for description.
 146  */
 147 static status_t get_nonce(private_nonce_payload_t *this, chunk_t *nonce)
 148 {
 149         nonce->len = this->nonce.len;
 150         nonce->ptr = allocator_clone_bytes(this->nonce.ptr, this->nonce.len);
 151         if (nonce->ptr == NULL)
 152         {
 153                 return OUT_OF_RES;
 154         }
 155         return SUCCESS;
 156 }
 157
 158 /**
 159  * Implements payload_t's get_encoding_rules function.
 160  * See #payload_s.get_encoding_rules for description.
 161  */
 162 static status_t get_encoding_rules(private_nonce_payload_t *this, encoding_rule_t **rules, size_t *rule_count)
 163 {
 164         *rules = nonce_payload_encodings;
 165         *rule_count = sizeof(nonce_payload_encodings) / sizeof(encoding_rule_t);
 166
 167         return SUCCESS;
 168 }
 169
 170 /**
 171  * Implements payload_t's get_type function.
 172  * See #payload_s.get_type for description.
 173  */
 174 static payload_type_t get_type(private_nonce_payload_t *this)
 175 {
 176         return SECURITY_ASSOCIATION;
 177 }
 178
 179 /**
 180  * Implements payload_t's get_next_type function.
 181  * See #payload_s.get_next_type for description.
 182  */
 183 static payload_type_t get_next_type(private_nonce_payload_t *this)
 184 {
 185         return (this->next_payload);
 186 }
 187
 188 /**
 189  * Implements payload_t's set_next_type function.
 190  * See #payload_s.set_next_type for description.
 191  */
 192 static status_t set_next_type(private_nonce_payload_t *this,payload_type_t type)
 193 {
 194         this->next_payload = type;
 195         return SUCCESS;
 196 }
 197
 198 /**
 199  * Implements payload_t's get_length function.
 200  * See #payload_s.get_length for description.
 201  */
 202 static size_t get_length(private_nonce_payload_t *this)
 203 {
 204         this->compute_length(this);
 205         return this->payload_length;
 206 }
 207
 208 /*
 209  * Described in header
 210  */
 211 nonce_payload_t *nonce_payload_create()
 212 {
 213         private_nonce_payload_t *this = allocator_alloc_thing(private_nonce_payload_t);
 214         if (this == NULL)
 215         {
 216                 return NULL;
 217         }
 218
 219         this->public.payload_interface.get_encoding_rules = (status_t (*) (payload_t *, encoding_rule_t **, size_t *) ) get_encoding_rules;
 220         this->public.payload_interface.get_length = (size_t (*) (payload_t *)) get_length;
 221         this->public.payload_interface.get_next_type = (payload_type_t (*) (payload_t *)) get_next_type;
 222         this->public.payload_interface.set_next_type = (status_t (*) (payload_t *,payload_type_t)) set_next_type;
 223         this->public.payload_interface.get_type = (payload_type_t (*) (payload_t *)) get_type;
 224         this->public.payload_interface.destroy = (status_t (*) (payload_t *))destroy;
 225         this->public.destroy = (status_t (*) (nonce_payload_t *)) destroy;
 226         this->public.set_nonce = (status_t (*) (nonce_payload_t *,chunk_t)) set_nonce;
 227         this->public.get_nonce = (status_t (*) (nonce_payload_t *,chunk_t*)) get_nonce;
 228
 229         this->critical = FALSE;
 230         this->next_payload = NO_PAYLOAD;
 231         this->payload_length = NONCE_PAYLOAD_HEADER_LENGTH;
 232
 233         return (&(this->public));
 234 }
 235
 236