src/libcharon/encoding/payloads/configuration_attribute.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 "configuration_attribute.h"
  21
  22 #include <encoding/payloads/encodings.h>
  23 #include <library.h>
  24 #include <daemon.h>
  25
  26 typedef struct private_configuration_attribute_t private_configuration_attribute_t;
  27
  28 /**
  29  * Private data of an configuration_attribute_t object.
  30  */
  31 struct private_configuration_attribute_t {
  32
  33         /**
  34          * Public configuration_attribute_t interface.
  35          */
  36         configuration_attribute_t public;
  37
  38         /**
  39          * Value encoded in length field?
  40          */
  41         bool af_flag;
  42
  43         /**
  44          * Reserved bit (af_flag in IKEv2)
  45          */
  46         bool reserved;
  47
  48         /**
  49          * Type of the attribute.
  50          */
  51         u_int16_t attr_type;
  52
  53         /**
  54          * Length of the attribute, value if af_flag set.
  55          */
  56         u_int16_t length_or_value;
  57
  58         /**
  59          * Attribute value as chunk.
  60          */
  61         chunk_t value;
  62
  63         /**
  64          * Payload type, PLV2_CONFIGURATION_ATTRIBUTE or DATA_ATTRIBUTE_V1
  65          */
  66         payload_type_t type;
  67 };
  68
  69 /**
  70  * Encoding rules for a IKEv2 configuration attribute / IKEv1 data attribute
  71  */
  72 static encoding_rule_t encodings_v2[] = {
  73         /* 1 reserved bit */
  74         { RESERVED_BIT,                                 offsetof(private_configuration_attribute_t, reserved)           },
  75         /* type of the attribute as 15 bit unsigned integer */
  76         { ATTRIBUTE_TYPE,                               offsetof(private_configuration_attribute_t, attr_type)          },
  77         /* Length of attribute value */
  78         { ATTRIBUTE_LENGTH,                             offsetof(private_configuration_attribute_t, length_or_value)},
  79         /* Value of attribute if attribute format flag is zero */
  80         { ATTRIBUTE_VALUE,                              offsetof(private_configuration_attribute_t, value)                      },
  81 };
  82
  83 /*
  84                            1                   2                   3
  85        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
  86       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  87       !R|         Attribute Type      !            Length             |
  88       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  89       |                                                               |
  90       ~                             Value                             ~
  91       |                                                               |
  92       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  93 */
  94
  95 /**
  96  * Encoding rules for a IKEv1 data attribute
  97  */
  98 static encoding_rule_t encodings_v1[] = {
  99         /* AF Flag */
 100         { ATTRIBUTE_FORMAT,                             offsetof(private_configuration_attribute_t, af_flag)            },
 101         /* type of the attribute as 15 bit unsigned integer */
 102         { ATTRIBUTE_TYPE,                               offsetof(private_configuration_attribute_t, attr_type)          },
 103         /* Length of attribute value */
 104         { ATTRIBUTE_LENGTH_OR_VALUE,    offsetof(private_configuration_attribute_t, length_or_value)},
 105         /* Value of attribute if attribute format flag is zero */
 106         { ATTRIBUTE_VALUE,                              offsetof(private_configuration_attribute_t, value)                      },
 107 };
 108
 109 /*
 110                            1                   2                   3
 111        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
 112       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 113       !F|         Attribute Type      !            Length             |
 114       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 115       |                                                               |
 116       ~                             Value                             ~
 117       |                                                               |
 118       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 119 */
 120
 121
 122 METHOD(payload_t, verify, status_t,
 123         private_configuration_attribute_t *this)
 124 {
 125         bool failed = FALSE;
 126
 127         switch (this->attr_type)
 128         {
 129                 case INTERNAL_IP4_ADDRESS:
 130                 case INTERNAL_IP4_NETMASK:
 131                 case INTERNAL_IP4_DNS:
 132                 case INTERNAL_IP4_NBNS:
 133                 case INTERNAL_ADDRESS_EXPIRY:
 134                 case INTERNAL_IP4_DHCP:
 135                         if (this->length_or_value != 0 && this->length_or_value != 4)
 136                         {
 137                                 failed = TRUE;
 138                         }
 139                         break;
 140                 case INTERNAL_IP4_SUBNET:
 141                         if (this->length_or_value != 0 && this->length_or_value != 8)
 142                         {
 143                                 failed = TRUE;
 144                         }
 145                         break;
 146                 case INTERNAL_IP6_ADDRESS:
 147                         if (this->type == PLV1_CONFIGURATION_ATTRIBUTE &&
 148                                 this->length_or_value == 16)
 149                         {       /* 16 bytes are correct for IKEv1, but older releases sent a
 150                                  * prefix byte so we still accept 0 or 17 as in IKEv2 */
 151                                 break;
 152                         }
 153                         /* fall-through */
 154                 case INTERNAL_IP6_SUBNET:
 155                         if (this->length_or_value != 0 && this->length_or_value != 17)
 156                         {
 157                                 failed = TRUE;
 158                         }
 159                         break;
 160                 case INTERNAL_IP6_DNS:
 161                 case INTERNAL_IP6_NBNS:
 162                 case INTERNAL_IP6_DHCP:
 163                         if (this->length_or_value != 0 && this->length_or_value != 16)
 164                         {
 165                                 failed = TRUE;
 166                         }
 167                         break;
 168                 case SUPPORTED_ATTRIBUTES:
 169                         if (this->length_or_value % 2)
 170                         {
 171                                 failed = TRUE;
 172                         }
 173                         break;
 174                 case APPLICATION_VERSION:
 175                 case INTERNAL_IP4_SERVER:
 176                 case INTERNAL_IP6_SERVER:
 177                 case XAUTH_TYPE:
 178                 case XAUTH_USER_NAME:
 179                 case XAUTH_USER_PASSWORD:
 180                 case XAUTH_PASSCODE:
 181                 case XAUTH_MESSAGE:
 182                 case XAUTH_CHALLENGE:
 183                 case XAUTH_DOMAIN:
 184                 case XAUTH_STATUS:
 185                 case XAUTH_NEXT_PIN:
 186                 case XAUTH_ANSWER:
 187                 case UNITY_BANNER:
 188                 case UNITY_SAVE_PASSWD:
 189                 case UNITY_DEF_DOMAIN:
 190                 case UNITY_SPLITDNS_NAME:
 191                 case UNITY_SPLIT_INCLUDE:
 192                 case UNITY_NATT_PORT:
 193                 case UNITY_LOCAL_LAN:
 194                 case UNITY_PFS:
 195                 case UNITY_FW_TYPE:
 196                 case UNITY_BACKUP_SERVERS:
 197                 case UNITY_DDNS_HOSTNAME:
 198                         /* any length acceptable */
 199                         break;
 200                 default:
 201                         DBG1(DBG_ENC, "unknown attribute type %N",
 202                                  configuration_attribute_type_names, this->attr_type);
 203                         break;
 204         }
 205
 206         if (failed)
 207         {
 208                 DBG1(DBG_ENC, "invalid attribute length %d for %N",
 209                          this->length_or_value, configuration_attribute_type_names,
 210                          this->attr_type);
 211                 return FAILED;
 212         }
 213         return SUCCESS;
 214 }
 215
 216 METHOD(payload_t, get_encoding_rules, int,
 217         private_configuration_attribute_t *this, encoding_rule_t **rules)
 218 {
 219         if (this->type == PLV2_CONFIGURATION_ATTRIBUTE)
 220         {
 221                 *rules = encodings_v2;
 222                 return countof(encodings_v2);
 223         }
 224         *rules = encodings_v1;
 225         return countof(encodings_v1);
 226 }
 227
 228 METHOD(payload_t, get_header_length, int,
 229         private_configuration_attribute_t *this)
 230 {
 231         return 4;
 232 }
 233
 234 METHOD(payload_t, get_type, payload_type_t,
 235         private_configuration_attribute_t *this)
 236 {
 237         return this->type;
 238 }
 239
 240 METHOD(payload_t, get_next_type, payload_type_t,
 241         private_configuration_attribute_t *this)
 242 {
 243         return PL_NONE;
 244 }
 245
 246 METHOD(payload_t, set_next_type, void,
 247         private_configuration_attribute_t *this, payload_type_t type)
 248 {
 249 }
 250
 251 METHOD(payload_t, get_length, size_t,
 252         private_configuration_attribute_t *this)
 253 {
 254         return get_header_length(this) + this->value.len;
 255 }
 256
 257 METHOD(configuration_attribute_t, get_cattr_type, configuration_attribute_type_t,
 258         private_configuration_attribute_t *this)
 259 {
 260         return this->attr_type;
 261 }
 262
 263 METHOD(configuration_attribute_t, get_chunk, chunk_t,
 264         private_configuration_attribute_t *this)
 265 {
 266         if (this->af_flag)
 267         {
 268                 return chunk_from_thing(this->length_or_value);
 269         }
 270         return this->value;
 271 }
 272
 273 METHOD(configuration_attribute_t, get_value, u_int16_t,
 274         private_configuration_attribute_t *this)
 275 {
 276         if (this->af_flag)
 277         {
 278                 return this->length_or_value;
 279         }
 280         return 0;
 281 }
 282
 283 METHOD2(payload_t, configuration_attribute_t, destroy, void,
 284         private_configuration_attribute_t *this)
 285 {
 286         free(this->value.ptr);
 287         free(this);
 288 }
 289
 290 /*
 291  * Described in header.
 292  */
 293 configuration_attribute_t *configuration_attribute_create(payload_type_t type)
 294 {
 295         private_configuration_attribute_t *this;
 296
 297         INIT(this,
 298                 .public = {
 299                         .payload_interface = {
 300                                 .verify = _verify,
 301                                 .get_encoding_rules = _get_encoding_rules,
 302                                 .get_header_length = _get_header_length,
 303                                 .get_length = _get_length,
 304                                 .get_next_type = _get_next_type,
 305                                 .set_next_type = _set_next_type,
 306                                 .get_type = _get_type,
 307                                 .destroy = _destroy,
 308                         },
 309                         .get_chunk = _get_chunk,
 310                         .get_value = _get_value,
 311                         .get_type = _get_cattr_type,
 312                         .destroy = _destroy,
 313                 },
 314                 .type = type
 315         );
 316         return &this->public;
 317 }
 318
 319 /*
 320  * Described in header.
 321  */
 322 configuration_attribute_t *configuration_attribute_create_chunk(
 323         payload_type_t type, configuration_attribute_type_t attr_type, chunk_t chunk)
 324 {
 325         private_configuration_attribute_t *this;
 326
 327         this = (private_configuration_attribute_t*)
 328                                                         configuration_attribute_create(type);
 329         this->attr_type = ((u_int16_t)attr_type) & 0x7FFF;
 330         this->value = chunk_clone(chunk);
 331         this->length_or_value = chunk.len;
 332
 333         return &this->public;
 334 }
 335
 336 /*
 337  * Described in header.
 338  */
 339 configuration_attribute_t *configuration_attribute_create_value(
 340                                         configuration_attribute_type_t attr_type, u_int16_t value)
 341 {
 342         private_configuration_attribute_t *this;
 343
 344         this = (private_configuration_attribute_t*)
 345                                         configuration_attribute_create(PLV1_CONFIGURATION_ATTRIBUTE);
 346         this->attr_type = ((u_int16_t)attr_type) & 0x7FFF;
 347         this->length_or_value = value;
 348         this->af_flag = TRUE;
 349
 350         return &this->public;
 351 }
 352