/** * @file proposal.h * * @brief Interface of proposal_t. * */ /* * Copyright (C) 2006 Martin Willi * 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 . * * 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. */ #ifndef PROPOSAL_H_ #define PROPOSAL_H_ typedef enum protocol_id_t protocol_id_t; typedef enum transform_type_t transform_type_t; typedef enum extended_sequence_numbers_t extended_sequence_numbers_t; typedef struct algorithm_t algorithm_t; typedef struct proposal_t proposal_t; #include #include #include #include #include #include #include #include /** * Protocol ID of a proposal. * * @ingroup config */ enum protocol_id_t { PROTO_NONE = 0, PROTO_IKE = 1, PROTO_AH = 2, PROTO_ESP = 3, }; /** * enum names for protocol_id_t * * @ingroup config */ extern enum_name_t *protocol_id_names; /** * Type of a transform, as in IKEv2 RFC 3.3.2. * * @ingroup config */ enum transform_type_t { UNDEFINED_TRANSFORM_TYPE = 241, ENCRYPTION_ALGORITHM = 1, PSEUDO_RANDOM_FUNCTION = 2, INTEGRITY_ALGORITHM = 3, DIFFIE_HELLMAN_GROUP = 4, EXTENDED_SEQUENCE_NUMBERS = 5 }; /** * enum names for transform_type_t. * * @ingroup config */ extern enum_name_t *transform_type_names; /** * Extended sequence numbers, as in IKEv2 RFC 3.3.2. * * @ingroup config */ enum extended_sequence_numbers_t { NO_EXT_SEQ_NUMBERS = 0, EXT_SEQ_NUMBERS = 1 }; /** * enum strings for extended_sequence_numbers_t. * * @ingroup config */ extern enum_name_t *extended_sequence_numbers_names; /** * Struct used to store different kinds of algorithms. The internal * lists of algorithms contain such structures. * * @ingroup config */ struct algorithm_t { /** * Value from an encryption_algorithm_t/integrity_algorithm_t/... */ u_int16_t algorithm; /** * the associated key size in bits, or zero if not needed */ u_int16_t key_size; }; /** * @brief Stores a set of algorithms used for an SA. * * A proposal stores algorithms for a specific * protocol. It can store algorithms for one protocol. * Proposals with multiple protocols are not supported, * as it's not specified in RFC4301 anymore. * * @b Constructors: * - proposal_create() * * @ingroup config */ struct proposal_t { /** * @brief Add an algorithm to the proposal. * * The algorithms are stored by priority, first added * is the most preferred. * Key size is only needed for encryption algorithms * with variable key size (such as AES). Must be set * to zero if key size is not specified. * The alg parameter accepts encryption_algorithm_t, * integrity_algorithm_t, dh_group_number_t and * extended_sequence_numbers_t. * * @param this calling object * @param type kind of algorithm * @param alg identifier for algorithm * @param key_size key size to use */ void (*add_algorithm) (proposal_t *this, transform_type_t type, u_int16_t alg, size_t key_size); /** * @brief Get an iterator over algorithms for a specifc algo type. * * @param this calling object * @param type kind of algorithm * @return iterator over algorithm_t's */ iterator_t *(*create_algorithm_iterator) (proposal_t *this, transform_type_t type); /** * @brief Get the algorithm for a type to use. * * If there are multiple algorithms, only the first is returned. * * @param this calling object * @param type kind of algorithm * @param[out] algo pointer which receives algorithm and key size * @return TRUE if algorithm of this kind available */ bool (*get_algorithm) (proposal_t *this, transform_type_t type, algorithm_t** algo); /** * @brief Check if the proposal has a specific DH group. * * @param this calling object * @param group group to check for * @return TRUE if algorithm included */ bool (*has_dh_group) (proposal_t *this, diffie_hellman_group_t group); /** * @brief Compare two proposal, and select a matching subset. * * If the proposals are for the same protocols (AH/ESP), they are * compared. If they have at least one algorithm of each type * in common, a resulting proposal of this kind is created. * * @param this calling object * @param other proposal to compair agains * @return * - selected proposal, if possible * - NULL, if proposals don't match */ proposal_t *(*select) (proposal_t *this, proposal_t *other); /** * @brief Get the protocol ID of the proposal. * * @param this calling object * @return protocol of the proposal */ protocol_id_t (*get_protocol) (proposal_t *this); /** * @brief Get the SPI of the proposal. * * @param this calling object * @return spi for proto */ u_int64_t (*get_spi) (proposal_t *this); /** * @brief Set the SPI of the proposal. * * @param this calling object * @param spi spi to set for proto */ void (*set_spi) (proposal_t *this, u_int64_t spi); /** * @brief Clone a proposal. * * @param this proposal to clone * @return clone of it */ proposal_t *(*clone) (proposal_t *this); /** * @brief Destroys the proposal object. * * @param this calling object */ void (*destroy) (proposal_t *this); }; /** * @brief Create a child proposal for AH, ESP or IKE. * * @param protocol protocol, such as PROTO_ESP * @return proposal_t object * * @ingroup config */ proposal_t *proposal_create(protocol_id_t protocol); /** * @brief Create a default proposal if nothing further specified. * * @param protocol protocol, such as PROTO_ESP * @return proposal_t object * * @ingroup config */ proposal_t *proposal_create_default(protocol_id_t protocol); /** * @brief Create a proposal from a string identifying the algorithms. * * The string is in the same form as a in the ipsec.conf file. * E.g.: aes128-sha2_256-modp2048 * 3des-md5 * An additional '!' at the end of the string forces this proposal, * without it the peer may choose another algorithm we support. * * @param protocol protocol, such as PROTO_ESP * @param algs algorithms as string * @return proposal_t object * * @ingroup config */ proposal_t *proposal_create_from_string(protocol_id_t protocol, const char *algs); #endif /* PROPOSAL_H_ */