Source/charon/payloads/sa_payload.c

   1 /**
   2  * @file sa_payload.h
   3  *
   4  * @brief Declaration of the class sa_payload_t.
   5  *
   6  * An object of this type represents an IKEv2 SA-Payload and contains proposal
   7  * substructures.
   8  *
   9  */
  10
  11 /*
  12  * Copyright (C) 2005 Jan Hutter, Martin Willi
  13  * Hochschule fuer Technik Rapperswil
  14  *
  15  * This program is free software; you can redistribute it and/or modify it
  16  * under the terms of the GNU General Public License as published by the
  17  * Free Software Foundation; either version 2 of the License, or (at your
  18  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
  19  *
  20  * This program is distributed in the hope that it will be useful, but
  21  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  22  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  23  * for more details.
  24  */
  25
  26 /* offsetof macro */
  27 #include <stddef.h>
  28
  29 #include "sa_payload.h"
  30
  31 #include "encodings.h"
  32 #include "../utils/allocator.h"
  33 #include "../utils/linked_list.h"
  34
  35
  36 /**
  37  * Private data of an sa_payload_t' Object
  38  *
  39  */
  40 typedef struct private_sa_payload_s private_sa_payload_t;
  41
  42 struct private_sa_payload_s {
  43         /**
  44          * public sa_payload_t interface
  45          */
  46         sa_payload_t public;
  47
  48         /**
  49          * next payload type
  50          */
  51         u_int8_t  next_payload;
  52
  53         /**
  54          * Critical flag
  55          */
  56         bool critical;
  57
  58         /**
  59          * Length of this payload
  60          */
  61         u_int16_t payload_length;
  62
  63         /**
  64          * Proposals in this payload are stored in a linked_list_t
  65          */
  66         linked_list_t * proposals;
  67
  68         /**
  69          * @brief Computes the length of this payload.
  70          *
  71          * @param this  calling private_sa_payload_t object
  72          * @return
  73          *                              SUCCESS in any case
  74          */
  75         status_t (*compute_length) (private_sa_payload_t *this);
  76 };
  77
  78 /**
  79  * Encoding rules to parse or generate a IKEv2-Header
  80  *
  81  * The defined offsets are the positions in a object of type
  82  * private_sa_payload_t.
  83  *
  84  */
  85 encoding_rule_t sa_payload_encodings[] = {
  86         /* 1 Byte next payload type, stored in the field next_payload */
  87         { U_INT_8,              offsetof(private_sa_payload_t, next_payload)                    },
  88         /* the critical bit */
  89         { FLAG,                 offsetof(private_sa_payload_t, critical)                                },
  90         /* 7 Bit reserved bits, nowhere stored */
  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         { RESERVED_BIT, 0                                                                                                               },
  98         /* Length of the whole SA payload*/
  99         { PAYLOAD_LENGTH,               offsetof(private_sa_payload_t, payload_length)  },
 100         /* Proposals are stored in a proposal substructure,
 101            offset points to a linked_list_t pointer */
 102         { PROPOSALS,            offsetof(private_sa_payload_t, proposals)                               }
 103 };
 104
 105 /**
 106  * Implements payload_t's and sa_payload_t's destroy function.
 107  * See #payload_s.destroy or sa_payload_s.destroy for description.
 108  */
 109 static status_t destroy(private_sa_payload_t *this)
 110 {
 111         /* all proposals are getting destroyed */
 112         while (this->proposals->get_count(this->proposals) > 0)
 113         {
 114                 proposal_substructure_t *current_proposal;
 115                 if (this->proposals->remove_last(this->proposals,(void **)&current_proposal) != SUCCESS)
 116                 {
 117                         break;
 118                 }
 119                 current_proposal->destroy(current_proposal);
 120         }
 121         this->proposals->destroy(this->proposals);
 122
 123         allocator_free(this);
 124
 125         return SUCCESS;
 126 }
 127
 128 /**
 129  * Implements payload_t's get_encoding_rules function.
 130  * See #payload_s.get_encoding_rules for description.
 131  */
 132 static status_t get_encoding_rules(private_sa_payload_t *this, encoding_rule_t **rules, size_t *rule_count)
 133 {
 134         *rules = sa_payload_encodings;
 135         *rule_count = sizeof(sa_payload_encodings) / sizeof(encoding_rule_t);
 136
 137         return SUCCESS;
 138 }
 139
 140 /**
 141  * Implements payload_t's get_type function.
 142  * See #payload_s.get_type for description.
 143  */
 144 static payload_type_t get_type(private_sa_payload_t *this)
 145 {
 146         return SECURITY_ASSOCIATION;
 147 }
 148
 149 /**
 150  * Implements payload_t's get_next_type function.
 151  * See #payload_s.get_next_type for description.
 152  */
 153 static payload_type_t get_next_type(private_sa_payload_t *this)
 154 {
 155         return (this->next_payload);
 156 }
 157
 158 /**
 159  * Implements payload_t's set_next_type function.
 160  * See #payload_s.set_next_type for description.
 161  */
 162 static status_t set_next_type(private_sa_payload_t *this,payload_type_t type)
 163 {
 164         this->next_payload = type;
 165         return SUCCESS;
 166 }
 167
 168 /**
 169  * Implements payload_t's get_length function.
 170  * See #payload_s.get_length for description.
 171  */
 172 static size_t get_length(private_sa_payload_t *this)
 173 {
 174         this->compute_length(this);
 175         return this->payload_length;
 176 }
 177
 178 /**
 179  * Implements sa_payload_t's create_proposal_substructure_iterator function.
 180  * See #sa_payload_s.create_proposal_substructure_iterator for description.
 181  */
 182 static status_t create_proposal_substructure_iterator (private_sa_payload_t *this,linked_list_iterator_t **iterator,bool forward)
 183 {
 184         return (this->proposals->create_iterator(this->proposals,iterator,forward));
 185 }
 186
 187 /**
 188  * Implements sa_payload_t's add_proposal_substructure function.
 189  * See #sa_payload_s.add_proposal_substructure for description.
 190  */
 191 static status_t add_proposal_substructure (private_sa_payload_t *this,proposal_substructure_t *proposal)
 192 {
 193         status_t status;
 194         status = this->proposals->insert_last(this->proposals,(void *) proposal);
 195         this->compute_length(this);
 196         return status;
 197 }
 198
 199 /**
 200  * Implements private_sa_payload_t's compute_length function.
 201  * See #private_sa_payload_s.compute_length for description.
 202  */
 203 static status_t compute_length (private_sa_payload_t *this)
 204 {
 205         linked_list_iterator_t *iterator;
 206         status_t status;
 207         size_t length = SA_PAYLOAD_HEADER_LENGTH;
 208         status = this->proposals->create_iterator(this->proposals,&iterator,TRUE);
 209         if (status != SUCCESS)
 210         {
 211                 return length;
 212         }
 213         while (iterator->has_next(iterator))
 214         {
 215                 payload_t *current_proposal;
 216                 iterator->current(iterator,(void **) &current_proposal);
 217                 length += current_proposal->get_length(current_proposal);
 218         }
 219         iterator->destroy(iterator);
 220
 221         this->payload_length = length;
 222
 223         return SUCCESS;
 224 }
 225
 226 /*
 227  * Described in header
 228  */
 229 sa_payload_t *sa_payload_create()
 230 {
 231         private_sa_payload_t *this = allocator_alloc_thing(private_sa_payload_t);
 232         if (this == NULL)
 233         {
 234                 return NULL;
 235         }
 236
 237         this->public.payload_interface.get_encoding_rules = (status_t (*) (payload_t *, encoding_rule_t **, size_t *) ) get_encoding_rules;
 238         this->public.payload_interface.get_length = (size_t (*) (payload_t *)) get_length;
 239         this->public.payload_interface.get_next_type = (payload_type_t (*) (payload_t *)) get_next_type;
 240         this->public.payload_interface.set_next_type = (status_t (*) (payload_t *,payload_type_t)) set_next_type;
 241         this->public.payload_interface.get_type = (payload_type_t (*) (payload_t *)) get_type;
 242         this->public.payload_interface.destroy = (status_t (*) (payload_t *))destroy;
 243         this->public.create_proposal_substructure_iterator = (status_t (*) (sa_payload_t *,linked_list_iterator_t **,bool)) create_proposal_substructure_iterator;
 244         this->public.add_proposal_substructure = (status_t (*) (sa_payload_t *,proposal_substructure_t *)) add_proposal_substructure;
 245         this->public.destroy = (status_t (*) (sa_payload_t *)) destroy;
 246
 247         /* private functions */
 248         this->compute_length = compute_length;
 249
 250         /* set default values of the fields */
 251         this->critical = SA_PAYLOAD_CRITICAL_FLAG;
 252         this->next_payload = NO_PAYLOAD;
 253         this->payload_length = SA_PAYLOAD_HEADER_LENGTH;
 254
 255         this->proposals = linked_list_create();
 256
 257         if (this->proposals == NULL)
 258         {
 259                 allocator_free(this);
 260                 return NULL;
 261         }
 262         return (&(this->public));
 263 }
 264
 265