src/libcharon/encoding/payloads/id_payload.c

   1 /*
   2  * Copyright (C) 2005-2010 Martin Willi
   3  * Copyright (C) 2010 revosec AG
   4  * Copyright (C) 2007 Tobias Brunner
   5  * Copyright (C) 2005 Jan Hutter
   6  *
   7  * Hochschule fuer Technik Rapperswil
   8  *
   9  * This program is free software; you can redistribute it and/or modify it
  10  * under the terms of the GNU General Public License as published by the
  11  * Free Software Foundation; either version 2 of the License, or (at your
  12  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
  13  *
  14  * This program is distributed in the hope that it will be useful, but
  15  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  16  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  17  * for more details.
  18  */
  19
  20 #include <stddef.h>
  21
  22 #include "id_payload.h"
  23
  24 #include <daemon.h>
  25 #include <encoding/payloads/encodings.h>
  26
  27 typedef struct private_id_payload_t private_id_payload_t;
  28
  29 /**
  30  * Private data of an id_payload_t object.
  31  *
  32  */
  33 struct private_id_payload_t {
  34         /**
  35          * Public id_payload_t interface.
  36          */
  37         id_payload_t public;
  38
  39         /**
  40          * one of ID_INITIATOR, ID_RESPONDER
  41          */
  42         payload_type_t payload_type;
  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          * Type of the ID Data.
  71          */
  72         u_int8_t id_type;
  73
  74         /**
  75          * The contained id data value.
  76          */
  77         chunk_t id_data;
  78 };
  79
  80 /**
  81  * Encoding rules to parse or generate a ID payload
  82  *
  83  * The defined offsets are the positions in a object of type
  84  * private_id_payload_t.
  85  */
  86 encoding_rule_t id_payload_encodings[] = {
  87         /* 1 Byte next payload type, stored in the field next_payload */
  88         { U_INT_8,                      offsetof(private_id_payload_t, next_payload)    },
  89         /* the critical bit */
  90         { FLAG,                         offsetof(private_id_payload_t, critical)                },
  91         /* 7 Bit reserved bits */
  92         { RESERVED_BIT,         offsetof(private_id_payload_t, reserved_bit[0]) },
  93         { RESERVED_BIT,         offsetof(private_id_payload_t, reserved_bit[1]) },
  94         { RESERVED_BIT,         offsetof(private_id_payload_t, reserved_bit[2]) },
  95         { RESERVED_BIT,         offsetof(private_id_payload_t, reserved_bit[3]) },
  96         { RESERVED_BIT,         offsetof(private_id_payload_t, reserved_bit[4]) },
  97         { RESERVED_BIT,         offsetof(private_id_payload_t, reserved_bit[5]) },
  98         { RESERVED_BIT,         offsetof(private_id_payload_t, reserved_bit[6]) },
  99         /* Length of the whole payload*/
 100         { PAYLOAD_LENGTH,       offsetof(private_id_payload_t, payload_length)  },
 101         /* 1 Byte ID type*/
 102         { U_INT_8,                      offsetof(private_id_payload_t, id_type)                 },
 103         /* 3 reserved bytes */
 104         { RESERVED_BYTE,        offsetof(private_id_payload_t, reserved_byte[0])},
 105         { RESERVED_BYTE,        offsetof(private_id_payload_t, reserved_byte[1])},
 106         { RESERVED_BYTE,        offsetof(private_id_payload_t, reserved_byte[2])},
 107         /* some id data bytes, length is defined in PAYLOAD_LENGTH */
 108         { ID_DATA,                      offsetof(private_id_payload_t, id_data)                 }
 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       !   ID Type     !                 RESERVED                      |
 118       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 119       !                                                               !
 120       ~                   Identification Data                         ~
 121       !                                                               !
 122       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 123 */
 124
 125 METHOD(payload_t, verify, status_t,
 126         private_id_payload_t *this)
 127 {
 128         if (this->id_type == 0 || this->id_type == 4)
 129         {
 130                 /* reserved IDs */
 131                 DBG1(DBG_ENC, "received ID with reserved type %d", this->id_type);
 132                 return FAILED;
 133         }
 134         return SUCCESS;
 135 }
 136
 137 METHOD(payload_t, get_encoding_rules, void,
 138         private_id_payload_t *this, encoding_rule_t **rules, size_t *rule_count)
 139 {
 140         *rules = id_payload_encodings;
 141         *rule_count = countof(id_payload_encodings);
 142 }
 143
 144 METHOD(payload_t, get_type, payload_type_t,
 145         private_id_payload_t *this)
 146 {
 147         return this->payload_type;
 148 }
 149
 150 METHOD(payload_t, get_next_type, payload_type_t,
 151         private_id_payload_t *this)
 152 {
 153         return this->next_payload;
 154 }
 155
 156 METHOD(payload_t, set_next_type, void,
 157         private_id_payload_t *this, payload_type_t type)
 158 {
 159         this->next_payload = type;
 160 }
 161
 162 METHOD(payload_t, get_length, size_t,
 163         private_id_payload_t *this)
 164 {
 165         return this->payload_length;
 166 }
 167
 168 METHOD(id_payload_t, get_identification, identification_t*,
 169         private_id_payload_t *this)
 170 {
 171         return identification_create_from_encoding(this->id_type, this->id_data);
 172 }
 173
 174 METHOD2(payload_t, id_payload_t, destroy, void,
 175         private_id_payload_t *this)
 176 {
 177         free(this->id_data.ptr);
 178         free(this);
 179 }
 180
 181 /*
 182  * Described in header.
 183  */
 184 id_payload_t *id_payload_create(payload_type_t payload_type)
 185 {
 186         private_id_payload_t *this;
 187
 188         INIT(this,
 189                 .public = {
 190                         .payload_interface = {
 191                                 .verify = _verify,
 192                                 .get_encoding_rules = _get_encoding_rules,
 193                                 .get_length = _get_length,
 194                                 .get_next_type = _get_next_type,
 195                                 .set_next_type = _set_next_type,
 196                                 .get_type = _get_type,
 197                                 .destroy = _destroy,
 198                         },
 199                         .get_identification = _get_identification,
 200                         .destroy = _destroy,
 201                 },
 202                 .next_payload = NO_PAYLOAD,
 203                 .payload_length = ID_PAYLOAD_HEADER_LENGTH,
 204                 .payload_type = payload_type,
 205         );
 206         return &this->public;
 207 }
 208
 209 /*
 210  * Described in header.
 211  */
 212 id_payload_t *id_payload_create_from_identification(payload_type_t payload_type,
 213                                                                                                         identification_t *id)
 214 {
 215         private_id_payload_t *this;
 216
 217         this = (private_id_payload_t*)id_payload_create(payload_type);
 218         this->id_data = chunk_clone(id->get_encoding(id));
 219         this->id_type = id->get_type(id);
 220         this->payload_length += this->id_data.len;
 221
 222         return &this->public;
 223 }