/** * @file sa_payload.c * * @brief Implementation of sa_payload_t. * */ /* * 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. */ #include #include "sa_payload.h" #include #include #include typedef struct private_sa_payload_t private_sa_payload_t; /** * Private data of an sa_payload_t object. * */ struct private_sa_payload_t { /** * Public sa_payload_t interface. */ sa_payload_t public; /** * Next payload type. */ u_int8_t next_payload; /** * Critical flag. */ bool critical; /** * Length of this payload. */ u_int16_t payload_length; /** * Proposals in this payload are stored in a linked_list_t. */ linked_list_t * proposals; }; /** * Encoding rules to parse or generate a IKEv2-SA Payload * * The defined offsets are the positions in a object of type * private_sa_payload_t. * */ encoding_rule_t sa_payload_encodings[] = { /* 1 Byte next payload type, stored in the field next_payload */ { U_INT_8, offsetof(private_sa_payload_t, next_payload) }, /* the critical bit */ { FLAG, offsetof(private_sa_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 SA payload*/ { PAYLOAD_LENGTH, offsetof(private_sa_payload_t, payload_length) }, /* Proposals are stored in a proposal substructure, offset points to a linked_list_t pointer */ { PROPOSALS, offsetof(private_sa_payload_t, proposals) } }; /* 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 ! +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ! ! ~ ~ ! ! +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ */ /** * Implementation of payload_t.verify. */ static status_t verify(private_sa_payload_t *this) { int expected_number = 1, current_number; status_t status = SUCCESS; iterator_t *iterator; proposal_substructure_t *current_proposal; bool first = TRUE; /* check proposal numbering */ iterator = this->proposals->create_iterator(this->proposals,TRUE); while(iterator->iterate(iterator, (void**)¤t_proposal)) { current_number = current_proposal->get_proposal_number(current_proposal); if (current_number < expected_number) { if (current_number != (expected_number + 1)) { DBG1(DBG_ENC, "proposal number is %d, expected %d or %d", current_number, expected_number, expected_number + 1); status = FAILED; break; } } else if (current_number < expected_number) { /* must not be smaller then proceeding one */ DBG1(DBG_ENC, "proposal number smaller than that of previous proposal"); status = FAILED; break; } status = current_proposal->payload_interface.verify(&(current_proposal->payload_interface)); if (status != SUCCESS) { DBG1(DBG_ENC, "PROPOSAL_SUBSTRUCTURE verification failed"); break; } first = FALSE; expected_number = current_number; } iterator->destroy(iterator); return status; } /** * Implementation of payload_t.destroy and sa_payload_t.destroy. */ static status_t destroy(private_sa_payload_t *this) { this->proposals->destroy_offset(this->proposals, offsetof(proposal_substructure_t, destroy)); free(this); return SUCCESS; } /** * Implementation of payload_t.get_encoding_rules. */ static void get_encoding_rules(private_sa_payload_t *this, encoding_rule_t **rules, size_t *rule_count) { *rules = sa_payload_encodings; *rule_count = sizeof(sa_payload_encodings) / sizeof(encoding_rule_t); } /** * Implementation of payload_t.get_type. */ static payload_type_t get_type(private_sa_payload_t *this) { return SECURITY_ASSOCIATION; } /** * Implementation of payload_t.get_next_type. */ static payload_type_t get_next_type(private_sa_payload_t *this) { return (this->next_payload); } /** * Implementation of payload_t.set_next_type. */ static void set_next_type(private_sa_payload_t *this,payload_type_t type) { this->next_payload = type; } /** * recompute length of the payload. */ static void compute_length (private_sa_payload_t *this) { iterator_t *iterator; payload_t *current_proposal; size_t length = SA_PAYLOAD_HEADER_LENGTH; iterator = this->proposals->create_iterator(this->proposals,TRUE); while (iterator->iterate(iterator, (void **)¤t_proposal)) { length += current_proposal->get_length(current_proposal); } iterator->destroy(iterator); this->payload_length = length; } /** * Implementation of payload_t.get_length. */ static size_t get_length(private_sa_payload_t *this) { compute_length(this); return this->payload_length; } /** * Implementation of sa_payload_t.create_proposal_substructure_iterator. */ static iterator_t *create_proposal_substructure_iterator (private_sa_payload_t *this,bool forward) { return this->proposals->create_iterator(this->proposals,forward); } /** * Implementation of sa_payload_t.add_proposal_substructure. */ static void add_proposal_substructure(private_sa_payload_t *this,proposal_substructure_t *proposal) { status_t status; u_int proposal_count = this->proposals->get_count(this->proposals); if (proposal_count > 0) { proposal_substructure_t *last_proposal; status = this->proposals->get_last(this->proposals,(void **) &last_proposal); /* last transform is now not anymore last one */ last_proposal->set_is_last_proposal(last_proposal, FALSE); } proposal->set_is_last_proposal(proposal, TRUE); proposal->set_proposal_number(proposal, proposal_count + 1); this->proposals->insert_last(this->proposals,(void *) proposal); compute_length(this); } /** * Implementation of sa_payload_t.add_proposal. */ static void add_proposal(private_sa_payload_t *this, proposal_t *proposal) { proposal_substructure_t *substructure; substructure = proposal_substructure_create_from_proposal(proposal); add_proposal_substructure(this, substructure); } /** * Implementation of sa_payload_t.get_proposals. */ static linked_list_t *get_proposals(private_sa_payload_t *this) { int struct_number = 0; int ignore_struct_number = 0; iterator_t *iterator; proposal_substructure_t *proposal_struct; linked_list_t *proposal_list; /* this list will hold our proposals */ proposal_list = linked_list_create(); /* we do not support proposals split up to two proposal substructures, as * AH+ESP bundles are not supported in RFC4301 anymore. * To handle such structures safely, we just skip proposals with multiple * protocols. */ iterator = this->proposals->create_iterator(this->proposals, TRUE); while (iterator->iterate(iterator, (void **)&proposal_struct)) { proposal_t *proposal; /* check if a proposal has a single protocol */ if (proposal_struct->get_proposal_number(proposal_struct) == struct_number) { if (ignore_struct_number < struct_number) { /* remova an already added, if first of series */ proposal_list->remove_last(proposal_list, (void**)&proposal); proposal->destroy(proposal); ignore_struct_number = struct_number; } continue; } struct_number++; proposal = proposal_struct->get_proposal(proposal_struct); if (proposal) { proposal_list->insert_last(proposal_list, proposal); } } iterator->destroy(iterator); return proposal_list; } /* * Described in header. */ sa_payload_t *sa_payload_create() { private_sa_payload_t *this = malloc_thing(private_sa_payload_t); /* public interface */ 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.create_proposal_substructure_iterator = (iterator_t* (*) (sa_payload_t *,bool)) create_proposal_substructure_iterator; this->public.add_proposal_substructure = (void (*) (sa_payload_t *,proposal_substructure_t *)) add_proposal_substructure; this->public.add_proposal = (void (*) (sa_payload_t*,proposal_t*))add_proposal; this->public.get_proposals = (linked_list_t* (*) (sa_payload_t *)) get_proposals; this->public.destroy = (void (*) (sa_payload_t *)) destroy; /* set default values of the fields */ this->critical = FALSE; this->next_payload = NO_PAYLOAD; this->payload_length = SA_PAYLOAD_HEADER_LENGTH; this->proposals = linked_list_create(); return &this->public; } /* * Described in header. */ sa_payload_t *sa_payload_create_from_proposal_list(linked_list_t *proposals) { iterator_t *iterator; proposal_t *proposal; sa_payload_t *sa_payload = sa_payload_create(); /* add every payload from the list */ iterator = proposals->create_iterator(proposals, TRUE); while (iterator->iterate(iterator, (void**)&proposal)) { add_proposal((private_sa_payload_t*)sa_payload, proposal); } iterator->destroy(iterator); return sa_payload; } /* * Described in header. */ sa_payload_t *sa_payload_create_from_proposal(proposal_t *proposal) { sa_payload_t *sa_payload = sa_payload_create(); add_proposal((private_sa_payload_t*)sa_payload, proposal); return sa_payload; }