src/libcharon/encoding/payloads/cp_payload.c

   1 /*
   2  * Copyright (C) 2005-2010 Martin Willi
   3  * Copyright (C) 2010 revosec AG
   4  * Copyright (C) 2005 Jan Hutter
   5  * Hochschule fuer Technik Rapperswil
   6  *
   7  * This program is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License as published by the
   9  * Free Software Foundation; either version 2 of the License, or (at your
  10  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
  11  *
  12  * This program is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  14  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15  * for more details.
  16  */
  17
  18 #include <stddef.h>
  19
  20 #include "cp_payload.h"
  21
  22 #include <encoding/payloads/encodings.h>
  23 #include <utils/linked_list.h>
  24
  25 ENUM(config_type_names, CFG_REQUEST, CFG_ACK,
  26         "CFG_REQUEST",
  27         "CFG_REPLY",
  28         "CFG_SET",
  29         "CFG_ACK",
  30 );
  31
  32 typedef struct private_cp_payload_t private_cp_payload_t;
  33
  34 /**
  35  * Private data of an cp_payload_t object.
  36  */
  37 struct private_cp_payload_t {
  38
  39         /**
  40          * Public cp_payload_t interface.
  41          */
  42         cp_payload_t public;
  43
  44         /**
  45          * Next payload type.
  46          */
  47         u_int8_t  next_payload;
  48
  49         /**
  50          * Critical flag.
  51          */
  52         bool critical;
  53
  54         /**
  55          * Reserved bits
  56          */
  57         bool reserved_bit[7];
  58
  59         /**
  60          * Reserved bytes
  61          */
  62         u_int8_t reserved_byte[3];
  63
  64         /**
  65          * Length of this payload.
  66          */
  67         u_int16_t payload_length;
  68
  69         /**
  70          * List of attributes, as configuration_attribute_t
  71          */
  72         linked_list_t *attributes;
  73
  74         /**
  75          * Config Type.
  76          */
  77         u_int8_t type;
  78 };
  79
  80 /**
  81  * Encoding rules to parse or generate a IKEv2-CP Payload
  82  *
  83  * The defined offsets are the positions in a object of type
  84  * private_cp_payload_t.
  85  */
  86 static encoding_rule_t encodings[] = {
  87         /* 1 Byte next payload type, stored in the field next_payload */
  88         { U_INT_8,                                      offsetof(private_cp_payload_t, next_payload)    },
  89         /* the critical bit */
  90         { FLAG,                                         offsetof(private_cp_payload_t, critical)                },
  91         /* 7 Bit reserved bits */
  92         { RESERVED_BIT,                         offsetof(private_cp_payload_t, reserved_bit[0]) },
  93         { RESERVED_BIT,                         offsetof(private_cp_payload_t, reserved_bit[1]) },
  94         { RESERVED_BIT,                         offsetof(private_cp_payload_t, reserved_bit[2]) },
  95         { RESERVED_BIT,                         offsetof(private_cp_payload_t, reserved_bit[3]) },
  96         { RESERVED_BIT,                         offsetof(private_cp_payload_t, reserved_bit[4]) },
  97         { RESERVED_BIT,                         offsetof(private_cp_payload_t, reserved_bit[5]) },
  98         { RESERVED_BIT,                         offsetof(private_cp_payload_t, reserved_bit[6]) },
  99         /* Length of the whole CP payload*/
 100         { PAYLOAD_LENGTH,                       offsetof(private_cp_payload_t, payload_length)  },
 101         /* Proposals are stored in a proposal substructure,
 102            offset points to a linked_list_t pointer */
 103         { U_INT_8,                                      offsetof(private_cp_payload_t, type)                    },
 104         /* 3 reserved bytes */
 105         { RESERVED_BYTE,                        offsetof(private_cp_payload_t, reserved_byte[0])},
 106         { RESERVED_BYTE,                        offsetof(private_cp_payload_t, reserved_byte[1])},
 107         { RESERVED_BYTE,                        offsetof(private_cp_payload_t, reserved_byte[2])},
 108         { CONFIGURATION_ATTRIBUTES,     offsetof(private_cp_payload_t, attributes)              }
 109 };
 110
 111 /*
 112                            1                   2                   3
 113        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
 114       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 115       ! Next Payload  !C! RESERVED    !         Payload Length        !
 116       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 117       !   CFG Type    !                    RESERVED                   !
 118       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 119       !                                                               !
 120       ~                   Configuration Attributes                    ~
 121       !                                                               !
 122       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 123 */
 124
 125 METHOD(payload_t, verify, status_t,
 126         private_cp_payload_t *this)
 127 {
 128         status_t status = SUCCESS;
 129         enumerator_t *enumerator;
 130         payload_t *attribute;
 131
 132         enumerator = this->attributes->create_enumerator(this->attributes);
 133         while (enumerator->enumerate(enumerator, &attribute))
 134         {
 135                 status = attribute->verify(attribute);
 136                 if (status != SUCCESS)
 137                 {
 138                         break;
 139                 }
 140         }
 141         enumerator->destroy(enumerator);
 142         return status;
 143 }
 144
 145 METHOD(payload_t, get_encoding_rules, int,
 146         private_cp_payload_t *this, encoding_rule_t **rules)
 147 {
 148         *rules = encodings;
 149         return countof(encodings);
 150 }
 151
 152 METHOD(payload_t, get_type, payload_type_t,
 153         private_cp_payload_t *this)
 154 {
 155         return CONFIGURATION;
 156 }
 157
 158 METHOD(payload_t, get_next_type, payload_type_t,
 159         private_cp_payload_t *this)
 160 {
 161         return this->next_payload;
 162 }
 163
 164 METHOD(payload_t, set_next_type, void,
 165         private_cp_payload_t *this,payload_type_t type)
 166 {
 167         this->next_payload = type;
 168 }
 169
 170 /**
 171  * recompute the length of the payload.
 172  */
 173 static void compute_length(private_cp_payload_t *this)
 174 {
 175         enumerator_t *enumerator;
 176         payload_t *attribute;
 177
 178         this->payload_length = CP_PAYLOAD_HEADER_LENGTH;
 179
 180         enumerator = this->attributes->create_enumerator(this->attributes);
 181         while (enumerator->enumerate(enumerator, &attribute))
 182         {
 183                 this->payload_length += attribute->get_length(attribute);
 184         }
 185         enumerator->destroy(enumerator);
 186 }
 187
 188 METHOD(payload_t, get_length, size_t,
 189         private_cp_payload_t *this)
 190 {
 191         return this->payload_length;
 192 }
 193
 194 METHOD(cp_payload_t, create_attribute_enumerator, enumerator_t*,
 195         private_cp_payload_t *this)
 196 {
 197         return this->attributes->create_enumerator(this->attributes);
 198 }
 199
 200 METHOD(cp_payload_t, add_attribute, void,
 201         private_cp_payload_t *this, configuration_attribute_t *attribute)
 202 {
 203         this->attributes->insert_last(this->attributes, attribute);
 204         compute_length(this);
 205 }
 206
 207 METHOD(cp_payload_t, get_config_type, config_type_t,
 208         private_cp_payload_t *this)
 209 {
 210         return this->type;
 211 }
 212
 213 METHOD2(payload_t, cp_payload_t, destroy, void,
 214         private_cp_payload_t *this)
 215 {
 216         this->attributes->destroy_offset(this->attributes,
 217                                                                 offsetof(configuration_attribute_t, destroy));
 218         free(this);
 219 }
 220
 221 /*
 222  * Described in header.
 223  */
 224 cp_payload_t *cp_payload_create_type(config_type_t type)
 225 {
 226         private_cp_payload_t *this;
 227
 228         INIT(this,
 229                 .public = {
 230                         .payload_interface = {
 231                                 .verify = _verify,
 232                                 .get_encoding_rules = _get_encoding_rules,
 233                                 .get_length = _get_length,
 234                                 .get_next_type = _get_next_type,
 235                                 .set_next_type = _set_next_type,
 236                                 .get_type = _get_type,
 237                                 .destroy = _destroy,
 238                         },
 239                         .create_attribute_enumerator = _create_attribute_enumerator,
 240                         .add_attribute = _add_attribute,
 241                         .get_type = _get_config_type,
 242                         .destroy = _destroy,
 243                 },
 244                 .next_payload = NO_PAYLOAD,
 245                 .payload_length = CP_PAYLOAD_HEADER_LENGTH,
 246                 .attributes = linked_list_create(),
 247                 .type = type,
 248         );
 249         return &this->public;
 250 }
 251
 252 /*
 253  * Described in header.
 254  */
 255 cp_payload_t *cp_payload_create()
 256 {
 257         return cp_payload_create_type(CFG_REQUEST);
 258 }