/* * Copyright (C) 2005-2010 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; /** * Reserved bits */ bool reserved[7]; /** * 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, offsetof(private_sa_payload_t, reserved[0]) }, { RESERVED_BIT, offsetof(private_sa_payload_t, reserved[1]) }, { RESERVED_BIT, offsetof(private_sa_payload_t, reserved[2]) }, { RESERVED_BIT, offsetof(private_sa_payload_t, reserved[3]) }, { RESERVED_BIT, offsetof(private_sa_payload_t, reserved[4]) }, { RESERVED_BIT, offsetof(private_sa_payload_t, reserved[5]) }, { RESERVED_BIT, offsetof(private_sa_payload_t, reserved[6]) }, /* 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 ! +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ! ! ~ ~ ! ! +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ */ METHOD(payload_t, verify, status_t, private_sa_payload_t *this) { int expected_number = 1, current_number; status_t status = SUCCESS; enumerator_t *enumerator; proposal_substructure_t *substruct; bool first = TRUE; /* check proposal numbering */ enumerator = this->proposals->create_enumerator(this->proposals); while (enumerator->enumerate(enumerator, (void**)&substruct)) { current_number = substruct->get_proposal_number(substruct); 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) { DBG1(DBG_ENC, "proposal number smaller than previous"); status = FAILED; break; } status = substruct->payload_interface.verify(&substruct->payload_interface); if (status != SUCCESS) { DBG1(DBG_ENC, "PROPOSAL_SUBSTRUCTURE verification failed"); break; } first = FALSE; expected_number = current_number; } enumerator->destroy(enumerator); return status; } METHOD(payload_t, get_encoding_rules, void, private_sa_payload_t *this, encoding_rule_t **rules, size_t *rule_count) { *rules = sa_payload_encodings; *rule_count = countof(sa_payload_encodings); } METHOD(payload_t, get_type, payload_type_t, private_sa_payload_t *this) { return SECURITY_ASSOCIATION; } METHOD(payload_t, get_next_type, payload_type_t, private_sa_payload_t *this) { return this->next_payload; } METHOD(payload_t, set_next_type, void, 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) { enumerator_t *enumerator; payload_t *current; size_t length = SA_PAYLOAD_HEADER_LENGTH; enumerator = this->proposals->create_enumerator(this->proposals); while (enumerator->enumerate(enumerator, (void **)¤t)) { length += current->get_length(current); } enumerator->destroy(enumerator); this->payload_length = length; } METHOD(payload_t, get_length, size_t, private_sa_payload_t *this) { return this->payload_length; } METHOD(sa_payload_t, add_proposal, void, private_sa_payload_t *this, proposal_t *proposal) { proposal_substructure_t *substruct, *last; u_int count; count = this->proposals->get_count(this->proposals); substruct = proposal_substructure_create_from_proposal(proposal); if (count > 0) { this->proposals->get_last(this->proposals, (void**)&last); /* last transform is now not anymore last one */ last->set_is_last_proposal(last, FALSE); } substruct->set_is_last_proposal(substruct, TRUE); if (proposal->get_number(proposal)) { /* use the selected proposals number, if any */ substruct->set_proposal_number(substruct, proposal->get_number(proposal)); } else { substruct->set_proposal_number(substruct, count + 1); } this->proposals->insert_last(this->proposals, substruct); compute_length(this); } METHOD(sa_payload_t, get_proposals, linked_list_t*, private_sa_payload_t *this) { int struct_number = 0; int ignore_struct_number = 0; enumerator_t *enumerator; proposal_substructure_t *substruct; linked_list_t *list; proposal_t *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. */ enumerator = this->proposals->create_enumerator(this->proposals); while (enumerator->enumerate(enumerator, &substruct)) { /* check if a proposal has a single protocol */ if (substruct->get_proposal_number(substruct) == struct_number) { if (ignore_struct_number < struct_number) { /* remove an already added, if first of series */ list->remove_last(list, (void**)&proposal); proposal->destroy(proposal); ignore_struct_number = struct_number; } continue; } struct_number++; proposal = substruct->get_proposal(substruct); if (proposal) { list->insert_last(list, proposal); } } enumerator->destroy(enumerator); return list; } METHOD(sa_payload_t, create_substructure_enumerator, enumerator_t*, private_sa_payload_t *this) { return this->proposals->create_enumerator(this->proposals); } METHOD2(payload_t, sa_payload_t, destroy, void, private_sa_payload_t *this) { this->proposals->destroy_offset(this->proposals, offsetof(proposal_substructure_t, destroy)); free(this); } /* * Described in header. */ sa_payload_t *sa_payload_create() { private_sa_payload_t *this; INIT(this, .public = { .payload_interface = { .verify = _verify, .get_encoding_rules = _get_encoding_rules, .get_length = _get_length, .get_next_type = _get_next_type, .set_next_type = _set_next_type, .get_type = _get_type, .destroy = _destroy, }, .add_proposal = _add_proposal, .get_proposals = _get_proposals, .create_substructure_enumerator = _create_substructure_enumerator, .destroy = _destroy, }, .next_payload = NO_PAYLOAD, .payload_length = SA_PAYLOAD_HEADER_LENGTH, .proposals = linked_list_create(), ); return &this->public; } /* * Described in header. */ sa_payload_t *sa_payload_create_from_proposal_list(linked_list_t *proposals) { private_sa_payload_t *this; enumerator_t *enumerator; proposal_t *proposal; this = (private_sa_payload_t*)sa_payload_create(); enumerator = proposals->create_enumerator(proposals); while (enumerator->enumerate(enumerator, &proposal)) { add_proposal(this, proposal); } enumerator->destroy(enumerator); return &this->public; } /* * Described in header. */ sa_payload_t *sa_payload_create_from_proposal(proposal_t *proposal) { private_sa_payload_t *this; this = (private_sa_payload_t*)sa_payload_create(); add_proposal(this, proposal); return &this->public; }