strongswan/src/libcharon/encoding/payloads/sa_payload.c

416 lines
11 KiB
C

/*
* 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 <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 "sa_payload.h"
#include <encoding/payloads/encodings.h>
#include <utils/linked_list.h>
#include <daemon.h>
/* IKEv1 situation */
#define SIT_IDENTITY_ONLY 1
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[8];
/**
* Length of this payload.
*/
u_int16_t payload_length;
/**
* Proposals in this payload are stored in a linked_list_t.
*/
linked_list_t *proposals;
/**
* Type of this payload, V1 or V2
*/
payload_type_t type;
/**
* IKEv1 DOI
*/
u_int32_t doi;
/**
* IKEv1 situation
*/
u_int32_t situation;
};
/**
* Encoding rules for IKEv1 SA payload
*/
static encoding_rule_t encodings_v1[] = {
/* 1 Byte next payload type, stored in the field next_payload */
{ U_INT_8, offsetof(private_sa_payload_t, next_payload) },
/* 8 reserved bits */
{ 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]) },
{ RESERVED_BIT, offsetof(private_sa_payload_t, reserved[7]) },
/* Length of the whole SA payload*/
{ PAYLOAD_LENGTH, offsetof(private_sa_payload_t, payload_length) },
/* DOI*/
{ U_INT_32, offsetof(private_sa_payload_t, doi) },
/* Situation*/
{ U_INT_32, offsetof(private_sa_payload_t, situation) },
/* Proposals are stored in a proposal substructure,
offset points to a linked_list_t pointer */
{ PROPOSALS_V1, 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 ! RESERVED ! Payload Length !
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
! DOI !
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
! Situation !
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
! !
~ <Proposals> ~
! !
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/
/**
* Encoding rules for IKEv2 SA payload
*/
static encoding_rule_t encodings_v2[] = {
/* 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 */
{ 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 !
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
! !
~ <Proposals> ~
! !
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/
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;
/* 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;
}
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)
{
if (this->type == SECURITY_ASSOCIATION_V1)
{
*rules = encodings_v1;
*rule_count = countof(encodings_v1);
}
else
{
*rules = encodings_v2;
*rule_count = countof(encodings_v2);
}
}
METHOD(payload_t, get_type, payload_type_t,
private_sa_payload_t *this)
{
return this->type;
}
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;
if (this->type == SECURITY_ASSOCIATION_V1)
{
length = SA_PAYLOAD_V1_HEADER_LENGTH;
}
enumerator = this->proposals->create_enumerator(this->proposals);
while (enumerator->enumerate(enumerator, (void **)&current))
{
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(payload_t, destroy));
free(this);
}
/*
* Described in header.
*/
sa_payload_t *sa_payload_create(payload_type_t type)
{
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,
.proposals = linked_list_create(),
.type = type,
/* for IKEv1 only */
.doi = IKEV1_DOI_IPSEC,
.situation = SIT_IDENTITY_ONLY,
);
compute_length(this);
return &this->public;
}
/*
* Described in header.
*/
sa_payload_t *sa_payload_create_from_proposal_list(payload_type_t type,
linked_list_t *proposals)
{
sa_payload_t *this;
enumerator_t *enumerator;
proposal_t *proposal;
this = sa_payload_create(type);
enumerator = proposals->create_enumerator(proposals);
while (enumerator->enumerate(enumerator, &proposal))
{
this->add_proposal(this, proposal);
}
enumerator->destroy(enumerator);
return this;
}
/*
* Described in header.
*/
sa_payload_t *sa_payload_create_from_proposal(payload_type_t type,
proposal_t *proposal)
{
sa_payload_t *this;
this = sa_payload_create(type);
this->add_proposal(this, proposal);
return this;
}