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                 case P_CSCF_IP4_ADDRESS:
 136                         if (this->length_or_value != 0 && this->length_or_value != 4)
 137                         {
 138                                 failed = TRUE;
 139                         }
 140                         break;
 141                 case INTERNAL_IP4_SUBNET:
 142                         if (this->length_or_value != 0 && this->length_or_value != 8)
 143                         {
 144                                 failed = TRUE;
 145                         }
 146                         break;
 147                 case INTERNAL_IP6_ADDRESS:
 148                         if (this->type == PLV1_CONFIGURATION_ATTRIBUTE &&
 149                                 this->length_or_value == 16)
 150                         {       /* 16 bytes are correct for IKEv1, but older releases sent a
 151                                  * prefix byte so we still accept 0 or 17 as in IKEv2 */
 152                                 break;
 153                         }
 154                         /* fall-through */
 155                 case INTERNAL_IP6_SUBNET:
 156                         if (this->length_or_value != 0 && this->length_or_value != 17)
 157                         {
 158                                 failed = TRUE;
 159                         }
 160                         break;
 161                 case INTERNAL_IP6_DNS:
 162                 case INTERNAL_IP6_NBNS:
 163                 case INTERNAL_IP6_DHCP:
 164                 case P_CSCF_IP6_ADDRESS:
 165                         if (this->length_or_value != 0 && this->length_or_value != 16)
 166                         {
 167                                 failed = TRUE;
 168                         }
 169                         break;
 170                 case SUPPORTED_ATTRIBUTES:
 171                         if (this->length_or_value % 2)
 172                         {
 173                                 failed = TRUE;
 174                         }
 175                         break;
 176                 case APPLICATION_VERSION:
 177                 case INTERNAL_IP4_SERVER:
 178                 case INTERNAL_IP6_SERVER:
 179                 case XAUTH_TYPE:
 180                 case XAUTH_USER_NAME:
 181                 case XAUTH_USER_PASSWORD:
 182                 case XAUTH_PASSCODE:
 183                 case XAUTH_MESSAGE:
 184                 case XAUTH_CHALLENGE:
 185                 case XAUTH_DOMAIN:
 186                 case XAUTH_STATUS:
 187                 case XAUTH_NEXT_PIN:
 188                 case XAUTH_ANSWER:
 189                 case UNITY_BANNER:
 190                 case UNITY_SAVE_PASSWD:
 191                 case UNITY_DEF_DOMAIN:
 192                 case UNITY_SPLITDNS_NAME:
 193                 case UNITY_SPLIT_INCLUDE:
 194                 case UNITY_NATT_PORT:
 195                 case UNITY_LOCAL_LAN:
 196                 case UNITY_PFS:
 197                 case UNITY_FW_TYPE:
 198                 case UNITY_BACKUP_SERVERS:
 199                 case UNITY_DDNS_HOSTNAME:
 200                         /* any length acceptable */
 201                         break;
 202                 default:
 203                         DBG1(DBG_ENC, "unknown attribute type %N",
 204                                  configuration_attribute_type_names, this->attr_type);
 205                         break;
 206         }
 207
 208         if (failed)
 209         {
 210                 DBG1(DBG_ENC, "invalid attribute length %d for %N",
 211                          this->length_or_value, configuration_attribute_type_names,
 212                          this->attr_type);
 213                 return FAILED;
 214         }
 215         return SUCCESS;
 216 }
 217
 218 METHOD(payload_t, get_encoding_rules, int,
 219         private_configuration_attribute_t *this, encoding_rule_t **rules)
 220 {
 221         if (this->type == PLV2_CONFIGURATION_ATTRIBUTE)
 222         {
 223                 *rules = encodings_v2;
 224                 return countof(encodings_v2);
 225         }
 226         *rules = encodings_v1;
 227         return countof(encodings_v1);
 228 }
 229
 230 METHOD(payload_t, get_header_length, int,
 231         private_configuration_attribute_t *this)
 232 {
 233         return 4;
 234 }
 235
 236 METHOD(payload_t, get_type, payload_type_t,
 237         private_configuration_attribute_t *this)
 238 {
 239         return this->type;
 240 }
 241
 242 METHOD(payload_t, get_next_type, payload_type_t,
 243         private_configuration_attribute_t *this)
 244 {
 245         return PL_NONE;
 246 }
 247
 248 METHOD(payload_t, set_next_type, void,
 249         private_configuration_attribute_t *this, payload_type_t type)
 250 {
 251 }
 252
 253 METHOD(payload_t, get_length, size_t,
 254         private_configuration_attribute_t *this)
 255 {
 256         return get_header_length(this) + this->value.len;
 257 }
 258
 259 METHOD(configuration_attribute_t, get_cattr_type, configuration_attribute_type_t,
 260         private_configuration_attribute_t *this)
 261 {
 262         return this->attr_type;
 263 }
 264
 265 METHOD(configuration_attribute_t, get_chunk, chunk_t,
 266         private_configuration_attribute_t *this)
 267 {
 268         if (this->af_flag)
 269         {
 270                 return chunk_from_thing(this->length_or_value);
 271         }
 272         return this->value;
 273 }
 274
 275 METHOD(configuration_attribute_t, get_value, u_int16_t,
 276         private_configuration_attribute_t *this)
 277 {
 278         if (this->af_flag)
 279         {
 280                 return this->length_or_value;
 281         }
 282         return 0;
 283 }
 284
 285 METHOD2(payload_t, configuration_attribute_t, destroy, void,
 286         private_configuration_attribute_t *this)
 287 {
 288         free(this->value.ptr);
 289         free(this);
 290 }
 291
 292 /*
 293  * Described in header.
 294  */
 295 configuration_attribute_t *configuration_attribute_create(payload_type_t type)
 296 {
 297         private_configuration_attribute_t *this;
 298
 299         INIT(this,
 300                 .public = {
 301                         .payload_interface = {
 302                                 .verify = _verify,
 303                                 .get_encoding_rules = _get_encoding_rules,
 304                                 .get_header_length = _get_header_length,
 305                                 .get_length = _get_length,
 306                                 .get_next_type = _get_next_type,
 307                                 .set_next_type = _set_next_type,
 308                                 .get_type = _get_type,
 309                                 .destroy = _destroy,
 310                         },
 311                         .get_chunk = _get_chunk,
 312                         .get_value = _get_value,
 313                         .get_type = _get_cattr_type,
 314                         .destroy = _destroy,
 315                 },
 316                 .type = type
 317         );
 318         return &this->public;
 319 }
 320
 321 /*
 322  * Described in header.
 323  */
 324 configuration_attribute_t *configuration_attribute_create_chunk(
 325         payload_type_t type, configuration_attribute_type_t attr_type, chunk_t chunk)
 326 {
 327         private_configuration_attribute_t *this;
 328
 329         this = (private_configuration_attribute_t*)
 330                                                         configuration_attribute_create(type);
 331         this->attr_type = ((u_int16_t)attr_type) & 0x7FFF;
 332         this->value = chunk_clone(chunk);
 333         this->length_or_value = chunk.len;
 334
 335         return &this->public;
 336 }
 337
 338 /*
 339  * Described in header.
 340  */
 341 configuration_attribute_t *configuration_attribute_create_value(
 342                                         configuration_attribute_type_t attr_type, u_int16_t value)
 343 {
 344         private_configuration_attribute_t *this;
 345
 346         this = (private_configuration_attribute_t*)
 347                                         configuration_attribute_create(PLV1_CONFIGURATION_ATTRIBUTE);
 348         this->attr_type = ((u_int16_t)attr_type) & 0x7FFF;
 349         this->length_or_value = value;
 350         this->af_flag = TRUE;
 351
 352         return &this->public;
 353 }
 354