strongSwan

/*

 * Copyright (C) 2005-2009 Martin Willi

 * Copyright (C) 2005 Jan Hutter

 * Hochschule fuer Technik Rapperswil

 *

 * This program is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License as published by the

 * Free Software Foundation; either version 2 of the License, or (at your

 * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.

 *

 * This program is distributed in the hope that it will be useful, but

 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY

 * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * for more details.

 */

#include <stddef.h>

#include "cp_payload.h"

#include <encoding/payloads/encodings.h>

#include <utils/linked_list.h>

ENUM(config_type_names, CFG_REQUEST, CFG_ACK,

    "CFG_REQUEST",

    "CFG_REPLY",

    "CFG_SET",

    "CFG_ACK",

);

typedef struct private_cp_payload_t private_cp_payload_t;

/**

 * Private data of an cp_payload_t object.

 *

 */

struct private_cp_payload_t {

    /**

     * Public cp_payload_t interface.

     */

    cp_payload_t public;

    /**

     * Next payload type.

     */

    u_int8_t  next_payload;

    /**

     * Critical flag.

     */

    bool critical;

    /**

     * Length of this payload.

     */

    u_int16_t payload_length;

    /**

     * List of attributes, as configuration_attribute_t

     */

    linked_list_t *attributes;

    /**

     * Config Type.

     */

    u_int8_t type;

};

/**

 * Encoding rules to parse or generate a IKEv2-CP Payload

 *

 * The defined offsets are the positions in a object of type

 * private_cp_payload_t.

 *

 */

encoding_rule_t cp_payload_encodings[] = {

    /* 1 Byte next payload type, stored in the field next_payload */

    { U_INT_8,        offsetof(private_cp_payload_t, next_payload)             },

    /* the critical bit */

    { FLAG,            offsetof(private_cp_payload_t, critical)                 },

    /* 7 Bit reserved bits, nowhere stored */

    { RESERVED_BIT,    0                                                         },

    { RESERVED_BIT,    0                                                         },

    { RESERVED_BIT,    0                                                         },

    { RESERVED_BIT,    0                                                         },

    { RESERVED_BIT,    0                                                         },

    { RESERVED_BIT,    0                                                         },

    { RESERVED_BIT,    0                                                         },

    /* Length of the whole CP payload*/

    { PAYLOAD_LENGTH,        offsetof(private_cp_payload_t, payload_length)     },

    /* Proposals are stored in a proposal substructure,

       offset points to a linked_list_t pointer */

    { U_INT_8,                offsetof(private_cp_payload_t, type)            },

    { RESERVED_BYTE,0                                                         },

    { RESERVED_BYTE,0                                                        },

    { RESERVED_BYTE,0                                                        },

    { CONFIGURATION_ATTRIBUTES,    offsetof(private_cp_payload_t, attributes)    }

};

/*

                           1                   2                   3

       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

      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      ! Next Payload  !C! RESERVED    !         Payload Length        !

      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      !   CFG Type    !                    RESERVED                   !

      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      !                                                               !

      ~                   Configuration Attributes                    ~

      !                                                               !

      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

*/

/**

 * Implementation of payload_t.verify.

 */

static status_t verify(private_cp_payload_t *this)

{

    status_t status = SUCCESS;

    enumerator_t *enumerator;

    payload_t *attribute;

    enumerator = this->attributes->create_enumerator(this->attributes);

    while (enumerator->enumerate(enumerator, &attribute))

    {

        status = attribute->verify(attribute);

        if (status != SUCCESS)

        {

            break;

        }

    }

    enumerator->destroy(enumerator);

    return status;

}

/**

 * Implementation of payload_t.get_encoding_rules.

 */

static void get_encoding_rules(private_cp_payload_t *this,

                               encoding_rule_t **rules, size_t *rule_count)

{

    *rules = cp_payload_encodings;

    *rule_count = sizeof(cp_payload_encodings) / sizeof(encoding_rule_t);

}

/**

 * Implementation of payload_t.get_type.

 */

static payload_type_t get_type(private_cp_payload_t *this)

{

    return CONFIGURATION;

}

/**

 * Implementation of payload_t.get_next_type.

 */

static payload_type_t get_next_type(private_cp_payload_t *this)

{

    return this->next_payload;

}

/**

 * Implementation of payload_t.set_next_type.

 */

static void set_next_type(private_cp_payload_t *this,payload_type_t type)

{

    this->next_payload = type;

}

/**

 * recompute the length of the payload.

 */

static void compute_length(private_cp_payload_t *this)

{

    enumerator_t *enumerator;

    payload_t *attribute;

    this->payload_length = CP_PAYLOAD_HEADER_LENGTH;

    enumerator = this->attributes->create_enumerator(this->attributes);

    while (enumerator->enumerate(enumerator, &attribute))

    {

        this->payload_length += attribute->get_length(attribute);

    }

    enumerator->destroy(enumerator);

}

/**

 * Implementation of payload_t.get_length.

 */

static size_t get_length(private_cp_payload_t *this)

{

    return this->payload_length;

}

/**

 * Implementation of cp_payload_t.create_attribute_enumerator.

 */

static enumerator_t *create_attribute_enumerator(private_cp_payload_t *this)

{

    return this->attributes->create_enumerator(this->attributes);

}

/**

 * Implementation of cp_payload_t.add_attribute.

 */

static void add_attribute(private_cp_payload_t *this,

                          configuration_attribute_t *attribute)

{

    this->attributes->insert_last(this->attributes, attribute);

    compute_length(this);

}

/**

 * Implementation of cp_payload_t.get_type.

 */

static config_type_t get_config_type(private_cp_payload_t *this)

{

    return this->type;

}

/**

 * Implementation of payload_t.destroy and cp_payload_t.destroy.

 */

static void destroy(private_cp_payload_t *this)

{

    this->attributes->destroy_offset(this->attributes,

                                offsetof(configuration_attribute_t, destroy));

    free(this);

}

/*

 * Described in header.

 */

cp_payload_t *cp_payload_create()

{

    private_cp_payload_t *this = malloc_thing(private_cp_payload_t);

    this->public.payload_interface.verify = (status_t (*) (payload_t *))verify;

    this->public.payload_interface.get_encoding_rules = (void (*) (payload_t *, encoding_rule_t **, size_t *) ) get_encoding_rules;

    this->public.payload_interface.get_length = (size_t (*) (payload_t *)) get_length;

    this->public.payload_interface.get_next_type = (payload_type_t (*) (payload_t *)) get_next_type;

    this->public.payload_interface.set_next_type = (void (*) (payload_t *,payload_type_t)) set_next_type;

    this->public.payload_interface.get_type = (payload_type_t (*) (payload_t *)) get_type;

    this->public.payload_interface.destroy = (void (*) (payload_t *))destroy;

    this->public.create_attribute_enumerator = (enumerator_t*(*)(cp_payload_t *))create_attribute_enumerator;

    this->public.add_attribute = (void (*) (cp_payload_t *,configuration_attribute_t*))add_attribute;

    this->public.get_type = (config_type_t (*) (cp_payload_t *))get_config_type;

    this->public.destroy = (void (*)(cp_payload_t *))destroy;

    /* set default values of the fields */

    this->critical = FALSE;

    this->next_payload = NO_PAYLOAD;

    this->payload_length = CP_PAYLOAD_HEADER_LENGTH;

    this->attributes = linked_list_create();

    this->type = CFG_REQUEST;

    return &this->public;

}

/*

 * Described in header.

 */

cp_payload_t *cp_payload_create_type(config_type_t type)

{

    private_cp_payload_t *this = (private_cp_payload_t*)cp_payload_create();

    this->type = type;

    return &this->public;

}