/* * Copyright (C) 2005-2006 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 . * * 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. * * $Id: ke_payload.c 3589 2008-03-13 14:14:44Z martin $ */ #include #include "ke_payload.h" #include typedef struct private_ke_payload_t private_ke_payload_t; /** * Private data of an ke_payload_t object. * */ struct private_ke_payload_t { /** * Public ke_payload_t interface. */ ke_payload_t public; /** * Next payload type. */ u_int8_t next_payload; /** * Critical flag. */ bool critical; /** * Length of this payload. */ u_int16_t payload_length; /** * DH Group Number. */ u_int16_t dh_group_number; /** * Key Exchange Data of this KE payload. */ chunk_t key_exchange_data; }; /** * Encoding rules to parse or generate a IKEv2-KE Payload. * * The defined offsets are the positions in a object of type * private_ke_payload_t. * */ encoding_rule_t ke_payload_encodings[] = { /* 1 Byte next payload type, stored in the field next_payload */ { U_INT_8, offsetof(private_ke_payload_t, next_payload) }, /* the critical bit */ { FLAG, offsetof(private_ke_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 payload*/ { PAYLOAD_LENGTH, offsetof(private_ke_payload_t, payload_length) }, /* DH Group number as 16 bit field*/ { U_INT_16, offsetof(private_ke_payload_t, dh_group_number) }, { RESERVED_BYTE, 0 }, { RESERVED_BYTE, 0 }, /* Key Exchange Data is from variable size */ { KEY_EXCHANGE_DATA, offsetof(private_ke_payload_t, key_exchange_data)} }; /* 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 ! +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ! DH Group # ! RESERVED ! +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ! ! ~ Key Exchange Data ~ ! ! +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ */ /** * Implementation of payload_t.verify. */ static status_t verify(private_ke_payload_t *this) { /* dh group is not verified in here */ return SUCCESS; } /** * Implementation of payload_t.destroy. */ static void destroy(private_ke_payload_t *this) { if (this->key_exchange_data.ptr != NULL) { free(this->key_exchange_data.ptr); } free(this); } /** * Implementation of payload_t.get_encoding_rules. */ static void get_encoding_rules(private_ke_payload_t *this, encoding_rule_t **rules, size_t *rule_count) { *rules = ke_payload_encodings; *rule_count = sizeof(ke_payload_encodings) / sizeof(encoding_rule_t); } /** * Implementation of payload_t.get_type. */ static payload_type_t get_type(private_ke_payload_t *this) { return KEY_EXCHANGE; } /** * Implementation of payload_t.get_next_type. */ static payload_type_t get_next_type(private_ke_payload_t *this) { return (this->next_payload); } /** * Implementation of payload_t.set_next_type. */ static void set_next_type(private_ke_payload_t *this,payload_type_t type) { this->next_payload = type; } /** * recompute the length of the payload. */ static void compute_length(private_ke_payload_t *this) { size_t length = KE_PAYLOAD_HEADER_LENGTH; if (this->key_exchange_data.ptr != NULL) { length += this->key_exchange_data.len; } this->payload_length = length; } /** * Implementation of payload_t.get_length. */ static size_t get_length(private_ke_payload_t *this) { compute_length(this); return this->payload_length; } /** * Implementation of ke_payload_t.get_key_exchange_data. */ static chunk_t get_key_exchange_data(private_ke_payload_t *this) { return (this->key_exchange_data); } /** * Implementation of ke_payload_t.set_key_exchange_data. */ static void set_key_exchange_data(private_ke_payload_t *this, chunk_t key_exchange_data) { /* destroy existing data first */ if (this->key_exchange_data.ptr != NULL) { /* free existing value */ free(this->key_exchange_data.ptr); this->key_exchange_data.ptr = NULL; this->key_exchange_data.len = 0; } this->key_exchange_data = chunk_clone(key_exchange_data); compute_length(this); } /** * Implementation of ke_payload_t.get_dh_group_number. */ static diffie_hellman_group_t get_dh_group_number(private_ke_payload_t *this) { return this->dh_group_number; } /** * Implementation of ke_payload_t.set_dh_group_number. */ static void set_dh_group_number(private_ke_payload_t *this, diffie_hellman_group_t dh_group_number) { this->dh_group_number = dh_group_number; } /* * Described in header */ ke_payload_t *ke_payload_create() { private_ke_payload_t *this = malloc_thing(private_ke_payload_t); /* interface functions */ 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; /* public functions */ this->public.get_key_exchange_data = (chunk_t (*) (ke_payload_t *)) get_key_exchange_data; this->public.set_key_exchange_data = (void (*) (ke_payload_t *,chunk_t)) set_key_exchange_data; this->public.get_dh_group_number = (diffie_hellman_group_t (*) (ke_payload_t *)) get_dh_group_number; this->public.set_dh_group_number =(void (*) (ke_payload_t *,diffie_hellman_group_t)) set_dh_group_number; this->public.destroy = (void (*) (ke_payload_t *)) destroy; /* set default values of the fields */ this->critical = FALSE; this->next_payload = NO_PAYLOAD; this->payload_length = KE_PAYLOAD_HEADER_LENGTH; this->key_exchange_data = chunk_empty; this->dh_group_number = MODP_NONE; return &this->public; } /* * Described in header */ ke_payload_t *ke_payload_create_from_diffie_hellman(diffie_hellman_t *dh) { private_ke_payload_t *this = (private_ke_payload_t*)ke_payload_create(); dh->get_my_public_value(dh, &this->key_exchange_data); this->dh_group_number = dh->get_dh_group(dh); compute_length(this); return &this->public; }