OpenBSD-4.6/sbin/isakmpd/ipsec.c
/* $OpenBSD: ipsec.c,v 1.132 2009/01/29 10:05:50 hshoexer Exp $ */
/* $EOM: ipsec.c,v 1.143 2000/12/11 23:57:42 niklas Exp $ */
/*
* Copyright (c) 1998, 1999, 2000, 2001 Niklas Hallqvist. All rights reserved.
* Copyright (c) 2001 Angelos D. Keromytis. All rights reserved.
* Copyright (c) 2001 Håkan Olsson. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* This code was written under funding by Ericsson Radio Systems.
*/
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <stdlib.h>
#include <string.h>
#include <net/if.h>
#include <net/pfvar.h>
#include "sysdep.h"
#include "attribute.h"
#include "conf.h"
#include "connection.h"
#include "constants.h"
#include "crypto.h"
#include "dh.h"
#include "doi.h"
#include "dpd.h"
#include "exchange.h"
#include "hash.h"
#include "ike_aggressive.h"
#include "ike_auth.h"
#include "ike_main_mode.h"
#include "ike_quick_mode.h"
#include "ipsec.h"
#include "ipsec_doi.h"
#include "isakmp.h"
#include "isakmp_cfg.h"
#include "isakmp_fld.h"
#include "isakmp_num.h"
#include "log.h"
#include "math_group.h"
#include "message.h"
#include "nat_traversal.h"
#include "pf_key_v2.h"
#include "prf.h"
#include "sa.h"
#include "timer.h"
#include "transport.h"
#include "util.h"
#include "x509.h"
extern int acquire_only;
/* Backwards compatibility. */
#ifndef NI_MAXHOST
#define NI_MAXHOST 1025
#endif
/* The replay window size used for all IPsec protocols if not overridden. */
#define DEFAULT_REPLAY_WINDOW 16
struct ipsec_decode_arg {
struct message *msg;
struct sa *sa;
struct proto *proto;
};
/* These variables hold the contacted peers ADT state. */
struct contact {
struct sockaddr *addr;
socklen_t len;
} *contacts = 0;
int contact_cnt = 0, contact_limit = 0;
static int addr_cmp(const void *, const void *);
static int ipsec_add_contact(struct message *);
static int ipsec_contacted(struct message *);
static int ipsec_debug_attribute(u_int16_t, u_int8_t *, u_int16_t,
void *);
static void ipsec_delete_spi(struct sa *, struct proto *, int);
static int16_t *ipsec_exchange_script(u_int8_t);
static void ipsec_finalize_exchange(struct message *);
static void ipsec_free_exchange_data(void *);
static void ipsec_free_proto_data(void *);
static void ipsec_free_sa_data(void *);
static struct keystate *ipsec_get_keystate(struct message *);
static u_int8_t *ipsec_get_spi(size_t *, u_int8_t, struct message *);
static int ipsec_handle_leftover_payload(struct message *, u_int8_t,
struct payload *);
static int ipsec_informational_post_hook(struct message *);
static int ipsec_informational_pre_hook(struct message *);
static int ipsec_initiator(struct message *);
static void ipsec_proto_init(struct proto *, char *);
static int ipsec_responder(struct message *);
static void ipsec_setup_situation(u_int8_t *);
static int ipsec_set_network(u_int8_t *, u_int8_t *, struct ipsec_sa *);
static size_t ipsec_situation_size(void);
static u_int8_t ipsec_spi_size(u_int8_t);
static int ipsec_validate_attribute(u_int16_t, u_int8_t *, u_int16_t,
void *);
static int ipsec_validate_exchange(u_int8_t);
static int ipsec_validate_id_information(u_int8_t, u_int8_t *, u_int8_t *,
size_t, struct exchange *);
static int ipsec_validate_key_information(u_int8_t *, size_t);
static int ipsec_validate_notification(u_int16_t);
static int ipsec_validate_proto(u_int8_t);
static int ipsec_validate_situation(u_int8_t *, size_t *, size_t);
static int ipsec_validate_transform_id(u_int8_t, u_int8_t);
static int ipsec_sa_tag(struct exchange *, struct sa *, struct sa *);
static struct doi ipsec_doi = {
{0}, IPSEC_DOI_IPSEC,
sizeof(struct ipsec_exch), sizeof(struct ipsec_sa),
sizeof(struct ipsec_proto),
ipsec_debug_attribute,
ipsec_delete_spi,
ipsec_exchange_script,
ipsec_finalize_exchange,
ipsec_free_exchange_data,
ipsec_free_proto_data,
ipsec_free_sa_data,
ipsec_get_keystate,
ipsec_get_spi,
ipsec_handle_leftover_payload,
ipsec_informational_post_hook,
ipsec_informational_pre_hook,
ipsec_is_attribute_incompatible,
ipsec_proto_init,
ipsec_setup_situation,
ipsec_situation_size,
ipsec_spi_size,
ipsec_validate_attribute,
ipsec_validate_exchange,
ipsec_validate_id_information,
ipsec_validate_key_information,
ipsec_validate_notification,
ipsec_validate_proto,
ipsec_validate_situation,
ipsec_validate_transform_id,
ipsec_initiator,
ipsec_responder,
ipsec_decode_ids
};
int16_t script_quick_mode[] = {
ISAKMP_PAYLOAD_HASH, /* Initiator -> responder. */
ISAKMP_PAYLOAD_SA,
ISAKMP_PAYLOAD_NONCE,
EXCHANGE_SCRIPT_SWITCH,
ISAKMP_PAYLOAD_HASH, /* Responder -> initiator. */
ISAKMP_PAYLOAD_SA,
ISAKMP_PAYLOAD_NONCE,
EXCHANGE_SCRIPT_SWITCH,
ISAKMP_PAYLOAD_HASH, /* Initiator -> responder. */
EXCHANGE_SCRIPT_END
};
int16_t script_new_group_mode[] = {
ISAKMP_PAYLOAD_HASH, /* Initiator -> responder. */
ISAKMP_PAYLOAD_SA,
EXCHANGE_SCRIPT_SWITCH,
ISAKMP_PAYLOAD_HASH, /* Responder -> initiator. */
ISAKMP_PAYLOAD_SA,
EXCHANGE_SCRIPT_END
};
struct dst_spi_proto_arg {
struct sockaddr *dst;
u_int32_t spi;
u_int8_t proto;
};
/*
* Check if SA matches what we are asking for through V_ARG. It has to
* be a finished phase 2 SA.
* if "proto" arg is 0, match any proto
*/
static int
ipsec_sa_check(struct sa *sa, void *v_arg)
{
struct dst_spi_proto_arg *arg = v_arg;
struct proto *proto;
struct sockaddr *dst, *src;
int incoming;
if (sa->phase != 2 || !(sa->flags & SA_FLAG_READY))
return 0;
sa->transport->vtbl->get_dst(sa->transport, &dst);
if (memcmp(sockaddr_addrdata(dst), sockaddr_addrdata(arg->dst),
sockaddr_addrlen(dst)) == 0)
incoming = 0;
else {
sa->transport->vtbl->get_src(sa->transport, &src);
if (memcmp(sockaddr_addrdata(src), sockaddr_addrdata(arg->dst),
sockaddr_addrlen(src)) == 0)
incoming = 1;
else
return 0;
}
for (proto = TAILQ_FIRST(&sa->protos); proto;
proto = TAILQ_NEXT(proto, link))
if ((arg->proto == 0 || proto->proto == arg->proto) &&
memcmp(proto->spi[incoming], &arg->spi, sizeof arg->spi)
== 0)
return 1;
return 0;
}
/* Find an SA with a "name" of DST, SPI & PROTO. */
struct sa *
ipsec_sa_lookup(struct sockaddr *dst, u_int32_t spi, u_int8_t proto)
{
struct dst_spi_proto_arg arg;
arg.dst = dst;
arg.spi = spi;
arg.proto = proto;
return sa_find(ipsec_sa_check, &arg);
}
/*
* Check if SA matches the flow of another SA in V_ARG. It has to
* be a finished non-replaced phase 2 SA.
* XXX At some point other selectors will matter here too.
*/
static int
ipsec_sa_check_flow(struct sa *sa, void *v_arg)
{
struct sa *sa2 = v_arg;
struct ipsec_sa *isa = sa->data, *isa2 = sa2->data;
if (sa == sa2 || sa->phase != 2 ||
(sa->flags & (SA_FLAG_READY | SA_FLAG_REPLACED)) != SA_FLAG_READY)
return 0;
if (isa->tproto != isa2->tproto || isa->sport != isa2->sport ||
isa->dport != isa2->dport)
return 0;
return isa->src_net->sa_family == isa2->src_net->sa_family &&
memcmp(sockaddr_addrdata(isa->src_net),
sockaddr_addrdata(isa2->src_net),
sockaddr_addrlen(isa->src_net)) == 0 &&
memcmp(sockaddr_addrdata(isa->src_mask),
sockaddr_addrdata(isa2->src_mask),
sockaddr_addrlen(isa->src_mask)) == 0 &&
memcmp(sockaddr_addrdata(isa->dst_net),
sockaddr_addrdata(isa2->dst_net),
sockaddr_addrlen(isa->dst_net)) == 0 &&
memcmp(sockaddr_addrdata(isa->dst_mask),
sockaddr_addrdata(isa2->dst_mask),
sockaddr_addrlen(isa->dst_mask)) == 0;
}
/*
* Construct a PF tag if specified in the configuration.
* It is possible to use variables to expand the tag:
* $id The string representation of the remote ID
* $domain The stripped domain part of the ID (for FQDN and UFQDN)
*/
static int
ipsec_sa_tag(struct exchange *exchange, struct sa *sa, struct sa *isakmp_sa)
{
char *format, *section;
char *id_string = NULL, *domain = NULL;
int error = -1;
size_t len;
sa->tag = NULL;
if (exchange->name == NULL ||
(section = exchange->name) == NULL ||
(format = conf_get_str(section, "PF-Tag")) == NULL)
return (0); /* ignore if not present */
len = PF_TAG_NAME_SIZE;
if ((sa->tag = calloc(1, len)) == NULL) {
log_error("ipsec_sa_tag: calloc");
goto fail;
}
if (strlcpy(sa->tag, format, len) >= len) {
log_print("ipsec_sa_tag: tag too long");
goto fail;
}
if (isakmp_sa->initiator)
id_string = ipsec_id_string(isakmp_sa->id_r,
isakmp_sa->id_r_len);
else
id_string = ipsec_id_string(isakmp_sa->id_i,
isakmp_sa->id_i_len);
if (strstr(format, "$id") != NULL) {
if (id_string == NULL) {
log_print("ipsec_sa_tag: cannot get ID");
goto fail;
}
if (expand_string(sa->tag, len, "$id", id_string) != 0) {
log_print("ipsec_sa_tag: failed to expand tag");
goto fail;
}
}
if (strstr(format, "$domain") != NULL) {
if (id_string == NULL) {
log_print("ipsec_sa_tag: cannot get ID");
goto fail;
}
if (strncmp(id_string, "fqdn/", strlen("fqdn/")) == 0)
domain = strchr(id_string, '.');
else if (strncmp(id_string, "ufqdn/", strlen("ufqdn/")) == 0)
domain = strchr(id_string, '@');
if (domain == NULL || strlen(domain) < 2) {
log_print("ipsec_sa_tag: no valid domain in ID %s",
id_string);
goto fail;
}
domain++;
if (expand_string(sa->tag, len, "$domain", domain) != 0) {
log_print("ipsec_sa_tag: failed to expand tag");
goto fail;
}
}
LOG_DBG((LOG_SA, 10, "ipsec_sa_tag: tag_len %ld tag \"%s\"",
strlen(sa->tag), sa->tag));
error = 0;
fail:
free(id_string);
if (error != 0) {
free(sa->tag);
sa->tag = NULL;
}
return (error);
}
/*
* Do IPsec DOI specific finalizations task for the exchange where MSG was
* the final message.
*/
static void
ipsec_finalize_exchange(struct message *msg)
{
struct sa *isakmp_sa = msg->isakmp_sa;
struct ipsec_sa *isa;
struct exchange *exchange = msg->exchange;
struct ipsec_exch *ie = exchange->data;
struct sa *sa = 0, *old_sa;
struct proto *proto, *last_proto = 0;
char *addr1, *addr2, *mask1, *mask2;
switch (exchange->phase) {
case 1:
switch (exchange->type) {
case ISAKMP_EXCH_ID_PROT:
case ISAKMP_EXCH_AGGRESSIVE:
isa = isakmp_sa->data;
isa->hash = ie->hash->type;
isa->prf_type = ie->prf_type;
isa->skeyid_len = ie->skeyid_len;
isa->skeyid_d = ie->skeyid_d;
isa->skeyid_a = ie->skeyid_a;
/* Prevents early free of SKEYID_*. */
ie->skeyid_a = ie->skeyid_d = 0;
/*
* If a lifetime was negotiated setup the expiration
* timers.
*/
if (isakmp_sa->seconds)
sa_setup_expirations(isakmp_sa);
if (isakmp_sa->flags & SA_FLAG_NAT_T_KEEPALIVE)
nat_t_setup_keepalive(isakmp_sa);
break;
}
break;
case 2:
switch (exchange->type) {
case IKE_EXCH_QUICK_MODE:
/*
* Tell the application(s) about the SPIs and key
* material.
*/
for (sa = TAILQ_FIRST(&exchange->sa_list); sa;
sa = TAILQ_NEXT(sa, next)) {
isa = sa->data;
if (exchange->initiator) {
/*
* Initiator is source, responder is
* destination.
*/
if (ipsec_set_network(ie->id_ci,
ie->id_cr, isa)) {
log_print(
"ipsec_finalize_exchange: "
"ipsec_set_network "
"failed");
return;
}
} else {
/*
* Responder is source, initiator is
* destination.
*/
if (ipsec_set_network(ie->id_cr,
ie->id_ci, isa)) {
log_print(
"ipsec_finalize_exchange: "
"ipsec_set_network "
"failed");
return;
}
}
if (ipsec_sa_tag(exchange, sa, isakmp_sa) == -1)
return;
for (proto = TAILQ_FIRST(&sa->protos),
last_proto = 0; proto;
proto = TAILQ_NEXT(proto, link)) {
if (pf_key_v2_set_spi(sa, proto,
0, isakmp_sa) ||
(last_proto &&
pf_key_v2_group_spis(sa,
last_proto, proto, 0)) ||
pf_key_v2_set_spi(sa, proto,
1, isakmp_sa) ||
(last_proto &&
pf_key_v2_group_spis(sa,
last_proto, proto, 1)))
/*
* XXX Tear down this
* exchange.
*/
return;
last_proto = proto;
}
if (sockaddr2text(isa->src_net, &addr1, 0))
addr1 = 0;
if (sockaddr2text(isa->src_mask, &mask1, 0))
mask1 = 0;
if (sockaddr2text(isa->dst_net, &addr2, 0))
addr2 = 0;
if (sockaddr2text(isa->dst_mask, &mask2, 0))
mask2 = 0;
LOG_DBG((LOG_EXCHANGE, 50,
"ipsec_finalize_exchange: src %s %s "
"dst %s %s tproto %u sport %u dport %u",
addr1 ? addr1 : "<??\?>",
mask1 ? mask1 : "<??\?>",
addr2 ? addr2 : "<??\?>",
mask2 ? mask2 : "<??\?>",
isa->tproto, ntohs(isa->sport),
ntohs(isa->dport)));
free(addr1);
free(mask1);
free(addr2);
free(mask2);
/*
* If this is not an SA acquired by the
* kernel, it needs to have a SPD entry
* (a.k.a. flow) set up.
*/
if (!(sa->flags & SA_FLAG_ONDEMAND ||
conf_get_str("General", "Acquire-Only") ||
acquire_only) &&
pf_key_v2_enable_sa(sa, isakmp_sa))
/* XXX Tear down this exchange. */
return;
/*
* Mark elder SAs with the same flow
* information as replaced.
*/
while ((old_sa = sa_find(ipsec_sa_check_flow,
sa)) != 0)
sa_mark_replaced(old_sa);
}
break;
}
}
}
/* Set the client addresses in ISA from SRC_ID and DST_ID. */
static int
ipsec_set_network(u_int8_t *src_id, u_int8_t *dst_id, struct ipsec_sa *isa)
{
int id;
char *name, *nat = NULL;
u_int8_t *nat_id = NULL;
size_t nat_sz;
if ((name = connection_passive_lookup_by_ids(src_id, dst_id)))
nat = conf_get_str(name, "NAT-ID");
if (nat) {
if ((nat_id = ipsec_build_id(nat, &nat_sz))) {
LOG_DBG((LOG_EXCHANGE, 50, "ipsec_set_network: SRC-NAT:"
" src: %s -> %s", name, nat));
src_id = nat_id;
} else
log_print("ipsec_set_network: ipsec_build_id"
" failed for NAT-ID: %s", nat);
}
/* Set source address/mask. */
id = GET_ISAKMP_ID_TYPE(src_id);
switch (id) {
case IPSEC_ID_IPV4_ADDR:
case IPSEC_ID_IPV4_ADDR_SUBNET:
isa->src_net = (struct sockaddr *)calloc(1,
sizeof(struct sockaddr_in));
if (!isa->src_net)
goto memfail;
isa->src_net->sa_family = AF_INET;
isa->src_net->sa_len = sizeof(struct sockaddr_in);
isa->src_mask = (struct sockaddr *)calloc(1,
sizeof(struct sockaddr_in));
if (!isa->src_mask)
goto memfail;
isa->src_mask->sa_family = AF_INET;
isa->src_mask->sa_len = sizeof(struct sockaddr_in);
break;
case IPSEC_ID_IPV6_ADDR:
case IPSEC_ID_IPV6_ADDR_SUBNET:
isa->src_net = (struct sockaddr *)calloc(1,
sizeof(struct sockaddr_in6));
if (!isa->src_net)
goto memfail;
isa->src_net->sa_family = AF_INET6;
isa->src_net->sa_len = sizeof(struct sockaddr_in6);
isa->src_mask = (struct sockaddr *)calloc(1,
sizeof(struct sockaddr_in6));
if (!isa->src_mask)
goto memfail;
isa->src_mask->sa_family = AF_INET6;
isa->src_mask->sa_len = sizeof(struct sockaddr_in6);
break;
case IPSEC_ID_IPV4_RANGE:
case IPSEC_ID_IPV6_RANGE:
case IPSEC_ID_DER_ASN1_DN:
case IPSEC_ID_DER_ASN1_GN:
case IPSEC_ID_KEY_ID:
default:
log_print("ipsec_set_network: ID type %d (%s) not supported",
id, constant_name(ipsec_id_cst, id));
return -1;
}
/* Net */
memcpy(sockaddr_addrdata(isa->src_net), src_id + ISAKMP_ID_DATA_OFF,
sockaddr_addrlen(isa->src_net));
/* Mask */
switch (id) {
case IPSEC_ID_IPV4_ADDR:
case IPSEC_ID_IPV6_ADDR:
memset(sockaddr_addrdata(isa->src_mask), 0xff,
sockaddr_addrlen(isa->src_mask));
break;
case IPSEC_ID_IPV4_ADDR_SUBNET:
case IPSEC_ID_IPV6_ADDR_SUBNET:
memcpy(sockaddr_addrdata(isa->src_mask), src_id +
ISAKMP_ID_DATA_OFF + sockaddr_addrlen(isa->src_net),
sockaddr_addrlen(isa->src_mask));
break;
}
memcpy(&isa->sport,
src_id + ISAKMP_ID_DOI_DATA_OFF + IPSEC_ID_PORT_OFF,
IPSEC_ID_PORT_LEN);
if (nat_id)
free(nat_id);
/* Set destination address. */
id = GET_ISAKMP_ID_TYPE(dst_id);
switch (id) {
case IPSEC_ID_IPV4_ADDR:
case IPSEC_ID_IPV4_ADDR_SUBNET:
isa->dst_net = (struct sockaddr *)calloc(1,
sizeof(struct sockaddr_in));
if (!isa->dst_net)
goto memfail;
isa->dst_net->sa_family = AF_INET;
isa->dst_net->sa_len = sizeof(struct sockaddr_in);
isa->dst_mask = (struct sockaddr *)calloc(1,
sizeof(struct sockaddr_in));
if (!isa->dst_mask)
goto memfail;
isa->dst_mask->sa_family = AF_INET;
isa->dst_mask->sa_len = sizeof(struct sockaddr_in);
break;
case IPSEC_ID_IPV6_ADDR:
case IPSEC_ID_IPV6_ADDR_SUBNET:
isa->dst_net = (struct sockaddr *)calloc(1,
sizeof(struct sockaddr_in6));
if (!isa->dst_net)
goto memfail;
isa->dst_net->sa_family = AF_INET6;
isa->dst_net->sa_len = sizeof(struct sockaddr_in6);
isa->dst_mask = (struct sockaddr *)calloc(1,
sizeof(struct sockaddr_in6));
if (!isa->dst_mask)
goto memfail;
isa->dst_mask->sa_family = AF_INET6;
isa->dst_mask->sa_len = sizeof(struct sockaddr_in6);
break;
}
/* Net */
memcpy(sockaddr_addrdata(isa->dst_net), dst_id + ISAKMP_ID_DATA_OFF,
sockaddr_addrlen(isa->dst_net));
/* Mask */
switch (id) {
case IPSEC_ID_IPV4_ADDR:
case IPSEC_ID_IPV6_ADDR:
memset(sockaddr_addrdata(isa->dst_mask), 0xff,
sockaddr_addrlen(isa->dst_mask));
break;
case IPSEC_ID_IPV4_ADDR_SUBNET:
case IPSEC_ID_IPV6_ADDR_SUBNET:
memcpy(sockaddr_addrdata(isa->dst_mask), dst_id +
ISAKMP_ID_DATA_OFF + sockaddr_addrlen(isa->dst_net),
sockaddr_addrlen(isa->dst_mask));
break;
}
memcpy(&isa->tproto, dst_id + ISAKMP_ID_DOI_DATA_OFF +
IPSEC_ID_PROTO_OFF, IPSEC_ID_PROTO_LEN);
memcpy(&isa->dport,
dst_id + ISAKMP_ID_DOI_DATA_OFF + IPSEC_ID_PORT_OFF,
IPSEC_ID_PORT_LEN);
return 0;
memfail:
log_error("ipsec_set_network: calloc () failed");
return -1;
}
/* Free the DOI-specific exchange data pointed to by VIE. */
static void
ipsec_free_exchange_data(void *vie)
{
struct ipsec_exch *ie = vie;
struct isakmp_cfg_attr *attr;
free(ie->sa_i_b);
free(ie->id_ci);
free(ie->id_cr);
free(ie->g_xi);
free(ie->g_xr);
free(ie->g_xy);
free(ie->skeyid);
free(ie->skeyid_d);
free(ie->skeyid_a);
free(ie->skeyid_e);
free(ie->hash_i);
free(ie->hash_r);
if (ie->group)
group_free(ie->group);
for (attr = LIST_FIRST(&ie->attrs); attr;
attr = LIST_FIRST(&ie->attrs)) {
LIST_REMOVE(attr, link);
if (attr->length)
free(attr->value);
free(attr);
}
}
/* Free the DOI-specific SA data pointed to by VISA. */
static void
ipsec_free_sa_data(void *visa)
{
struct ipsec_sa *isa = visa;
free(isa->src_net);
free(isa->src_mask);
free(isa->dst_net);
free(isa->dst_mask);
free(isa->skeyid_a);
free(isa->skeyid_d);
}
/* Free the DOI-specific protocol data of an SA pointed to by VIPROTO. */
static void
ipsec_free_proto_data(void *viproto)
{
struct ipsec_proto *iproto = viproto;
int i;
for (i = 0; i < 2; i++)
free(iproto->keymat[i]);
}
/* Return exchange script based on TYPE. */
static int16_t *
ipsec_exchange_script(u_int8_t type)
{
switch (type) {
case ISAKMP_EXCH_TRANSACTION:
return script_transaction;
case IKE_EXCH_QUICK_MODE:
return script_quick_mode;
case IKE_EXCH_NEW_GROUP_MODE:
return script_new_group_mode;
}
return 0;
}
/* Initialize this DOI, requires doi_init to already have been called. */
void
ipsec_init(void)
{
doi_register(&ipsec_doi);
}
/* Given a message MSG, return a suitable IV (or rather keystate). */
static struct keystate *
ipsec_get_keystate(struct message *msg)
{
struct keystate *ks;
struct hash *hash;
/* If we have already have an IV, use it. */
if (msg->exchange && msg->exchange->keystate) {
ks = malloc(sizeof *ks);
if (!ks) {
log_error("ipsec_get_keystate: malloc (%lu) failed",
(unsigned long) sizeof *ks);
return 0;
}
memcpy(ks, msg->exchange->keystate, sizeof *ks);
return ks;
}
/*
* For phase 2 when no SA yet is setup we need to hash the IV used by
* the ISAKMP SA concatenated with the message ID, and use that as an
* IV for further cryptographic operations.
*/
if (!msg->isakmp_sa->keystate) {
log_print("ipsec_get_keystate: no keystate in ISAKMP SA %p",
msg->isakmp_sa);
return 0;
}
ks = crypto_clone_keystate(msg->isakmp_sa->keystate);
if (!ks)
return 0;
hash = hash_get(((struct ipsec_sa *)msg->isakmp_sa->data)->hash);
hash->Init(hash->ctx);
LOG_DBG_BUF((LOG_CRYPTO, 80, "ipsec_get_keystate: final phase 1 IV",
ks->riv, ks->xf->blocksize));
hash->Update(hash->ctx, ks->riv, ks->xf->blocksize);
LOG_DBG_BUF((LOG_CRYPTO, 80, "ipsec_get_keystate: message ID",
((u_int8_t *) msg->iov[0].iov_base) + ISAKMP_HDR_MESSAGE_ID_OFF,
ISAKMP_HDR_MESSAGE_ID_LEN));
hash->Update(hash->ctx, ((u_int8_t *) msg->iov[0].iov_base) +
ISAKMP_HDR_MESSAGE_ID_OFF, ISAKMP_HDR_MESSAGE_ID_LEN);
hash->Final(hash->digest, hash->ctx);
crypto_init_iv(ks, hash->digest, ks->xf->blocksize);
LOG_DBG_BUF((LOG_CRYPTO, 80, "ipsec_get_keystate: phase 2 IV",
hash->digest, ks->xf->blocksize));
return ks;
}
static void
ipsec_setup_situation(u_int8_t *buf)
{
SET_IPSEC_SIT_SIT(buf + ISAKMP_SA_SIT_OFF, IPSEC_SIT_IDENTITY_ONLY);
}
static size_t
ipsec_situation_size(void)
{
return IPSEC_SIT_SIT_LEN;
}
static u_int8_t
ipsec_spi_size(u_int8_t proto)
{
return IPSEC_SPI_SIZE;
}
static int
ipsec_validate_attribute(u_int16_t type, u_int8_t * value, u_int16_t len,
void *vmsg)
{
struct message *msg = vmsg;
if (msg->exchange->phase == 1 &&
(type < IKE_ATTR_ENCRYPTION_ALGORITHM || type > IKE_ATTR_GROUP_ORDER))
return -1;
if (msg->exchange->phase == 2 &&
(type < IPSEC_ATTR_SA_LIFE_TYPE || type > IPSEC_ATTR_ECN_TUNNEL))
return -1;
return 0;
}
static int
ipsec_validate_exchange(u_int8_t exch)
{
return exch != IKE_EXCH_QUICK_MODE && exch != IKE_EXCH_NEW_GROUP_MODE;
}
static int
ipsec_validate_id_information(u_int8_t type, u_int8_t *extra, u_int8_t *buf,
size_t sz, struct exchange *exchange)
{
u_int8_t proto = GET_IPSEC_ID_PROTO(extra);
u_int16_t port = GET_IPSEC_ID_PORT(extra);
LOG_DBG((LOG_MESSAGE, 40,
"ipsec_validate_id_information: proto %d port %d type %d",
proto, port, type));
if (type < IPSEC_ID_IPV4_ADDR || type > IPSEC_ID_KEY_ID)
return -1;
switch (type) {
case IPSEC_ID_IPV4_ADDR:
LOG_DBG_BUF((LOG_MESSAGE, 40,
"ipsec_validate_id_information: IPv4", buf,
sizeof(struct in_addr)));
break;
case IPSEC_ID_IPV6_ADDR:
LOG_DBG_BUF((LOG_MESSAGE, 40,
"ipsec_validate_id_information: IPv6", buf,
sizeof(struct in6_addr)));
break;
case IPSEC_ID_IPV4_ADDR_SUBNET:
LOG_DBG_BUF((LOG_MESSAGE, 40,
"ipsec_validate_id_information: IPv4 network/netmask",
buf, 2 * sizeof(struct in_addr)));
break;
case IPSEC_ID_IPV6_ADDR_SUBNET:
LOG_DBG_BUF((LOG_MESSAGE, 40,
"ipsec_validate_id_information: IPv6 network/netmask",
buf, 2 * sizeof(struct in6_addr)));
break;
default:
break;
}
if (exchange->phase == 1 &&
(proto != IPPROTO_UDP || port != UDP_DEFAULT_PORT) &&
(proto != 0 || port != 0)) {
/*
* XXX SSH's ISAKMP tester fails this test (proto 17 - port
* 0).
*/
#ifdef notyet
return -1;
#else
log_print("ipsec_validate_id_information: dubious ID "
"information accepted");
#endif
}
/* XXX More checks? */
return 0;
}
static int
ipsec_validate_key_information(u_int8_t *buf, size_t sz)
{
/* XXX Not implemented yet. */
return 0;
}
static int
ipsec_validate_notification(u_int16_t type)
{
return type < IPSEC_NOTIFY_RESPONDER_LIFETIME ||
type > IPSEC_NOTIFY_INITIAL_CONTACT ? -1 : 0;
}
static int
ipsec_validate_proto(u_int8_t proto)
{
return proto < IPSEC_PROTO_IPSEC_AH ||
proto > IPSEC_PROTO_IPCOMP ? -1 : 0;
}
static int
ipsec_validate_situation(u_int8_t *buf, size_t *sz, size_t len)
{
if (len < IPSEC_SIT_SIT_OFF + IPSEC_SIT_SIT_LEN) {
log_print("ipsec_validate_situation: payload too short: %u",
(unsigned int) len);
return -1;
}
/* Currently only "identity only" situations are supported. */
if (GET_IPSEC_SIT_SIT(buf) != IPSEC_SIT_IDENTITY_ONLY)
return 1;
*sz = IPSEC_SIT_SIT_LEN;
return 0;
}
static int
ipsec_validate_transform_id(u_int8_t proto, u_int8_t transform_id)
{
switch (proto) {
/*
* As no unexpected protocols can occur, we just tie the
* default case to the first case, in order to silence a GCC
* warning.
*/
default:
case ISAKMP_PROTO_ISAKMP:
return transform_id != IPSEC_TRANSFORM_KEY_IKE;
case IPSEC_PROTO_IPSEC_AH:
return transform_id < IPSEC_AH_MD5 ||
transform_id > IPSEC_AH_RIPEMD ? -1 : 0;
case IPSEC_PROTO_IPSEC_ESP:
return transform_id < IPSEC_ESP_DES_IV64 ||
(transform_id > IPSEC_ESP_AES_128_CTR &&
transform_id < IPSEC_ESP_AES_MARS) ||
transform_id > IPSEC_ESP_AES_TWOFISH ? -1 : 0;
case IPSEC_PROTO_IPCOMP:
return transform_id < IPSEC_IPCOMP_OUI ||
transform_id > IPSEC_IPCOMP_V42BIS ? -1 : 0;
}
}
static int
ipsec_initiator(struct message *msg)
{
struct exchange *exchange = msg->exchange;
int (**script)(struct message *) = 0;
/* Check that the SA is coherent with the IKE rules. */
if (exchange->type != ISAKMP_EXCH_TRANSACTION &&
((exchange->phase == 1 && exchange->type != ISAKMP_EXCH_ID_PROT &&
exchange->type != ISAKMP_EXCH_AGGRESSIVE &&
exchange->type != ISAKMP_EXCH_INFO) ||
(exchange->phase == 2 && exchange->type != IKE_EXCH_QUICK_MODE &&
exchange->type != ISAKMP_EXCH_INFO))) {
log_print("ipsec_initiator: unsupported exchange type %d "
"in phase %d", exchange->type, exchange->phase);
return -1;
}
switch (exchange->type) {
case ISAKMP_EXCH_ID_PROT:
script = ike_main_mode_initiator;
break;
case ISAKMP_EXCH_AGGRESSIVE:
script = ike_aggressive_initiator;
break;
case ISAKMP_EXCH_TRANSACTION:
script = isakmp_cfg_initiator;
break;
case ISAKMP_EXCH_INFO:
return message_send_info(msg);
case IKE_EXCH_QUICK_MODE:
script = ike_quick_mode_initiator;
break;
default:
log_print("ipsec_initiator: unsupported exchange type %d",
exchange->type);
return -1;
}
/* Run the script code for this step. */
if (script)
return script[exchange->step] (msg);
return 0;
}
/*
* delete all SA's from addr with the associated proto and SPI's
*
* spis[] is an array of SPIs of size 16-octet for proto ISAKMP
* or 4-octet otherwise.
*/
static void
ipsec_delete_spi_list(struct sockaddr *addr, u_int8_t proto, u_int8_t *spis,
int nspis, char *type)
{
struct sa *sa;
char *peer;
char ids[1024];
int i;
for (i = 0; i < nspis; i++) {
if (proto == ISAKMP_PROTO_ISAKMP) {
u_int8_t *spi = spis + i * ISAKMP_HDR_COOKIES_LEN;
/*
* This really shouldn't happen in IPSEC DOI
* code, but Cisco VPN 3000 sends ISAKMP DELETE's
* this way.
*/
sa = sa_lookup_isakmp_sa(addr, spi);
} else {
u_int32_t spi = ((u_int32_t *)spis)[i];
sa = ipsec_sa_lookup(addr, spi, proto);
}
if (sa == NULL) {
LOG_DBG((LOG_SA, 30, "ipsec_delete_spi_list: could "
"not locate SA (SPI %08x, proto %u)",
((u_int32_t *)spis)[i], proto));
continue;
}
strlcpy(ids,
sa->doi->decode_ids("initiator id: %s, responder id: %s",
sa->id_i, sa->id_i_len, sa->id_r, sa->id_r_len, 0),
sizeof ids);
if (sockaddr2text(addr, &peer, 0))
peer = NULL;
/* only log deletion of SAs which are not soft expired yet */
if (sa->soft_death != NULL)
log_verbose("isakmpd: Peer %s made us delete live SA "
"%s for proto %d, %s", peer ? peer : "<unknown>",
sa->name ? sa->name : "<unnamed>", proto, ids);
LOG_DBG((LOG_SA, 30, "ipsec_delete_spi_list: "
"%s made us delete SA %p (%d references) for proto %d (%s)",
type, sa, sa->refcnt, proto, ids));
free(peer);
/* Delete the SA and search for the next */
sa_free(sa);
}
}
static int
ipsec_responder(struct message *msg)
{
struct exchange *exchange = msg->exchange;
int (**script)(struct message *) = 0;
struct payload *p;
u_int16_t type;
/* Check that a new exchange is coherent with the IKE rules. */
if (exchange->step == 0 && exchange->type != ISAKMP_EXCH_TRANSACTION &&
((exchange->phase == 1 && exchange->type != ISAKMP_EXCH_ID_PROT &&
exchange->type != ISAKMP_EXCH_AGGRESSIVE &&
exchange->type != ISAKMP_EXCH_INFO) ||
(exchange->phase == 2 && exchange->type != IKE_EXCH_QUICK_MODE &&
exchange->type != ISAKMP_EXCH_INFO))) {
message_drop(msg, ISAKMP_NOTIFY_UNSUPPORTED_EXCHANGE_TYPE,
0, 1, 0);
return -1;
}
LOG_DBG((LOG_MISC, 30, "ipsec_responder: phase %d exchange %d step %d",
exchange->phase, exchange->type, exchange->step));
switch (exchange->type) {
case ISAKMP_EXCH_ID_PROT:
script = ike_main_mode_responder;
break;
case ISAKMP_EXCH_AGGRESSIVE:
script = ike_aggressive_responder;
break;
case ISAKMP_EXCH_TRANSACTION:
script = isakmp_cfg_responder;
break;
case ISAKMP_EXCH_INFO:
TAILQ_FOREACH(p, &msg->payload[ISAKMP_PAYLOAD_NOTIFY], link) {
type = GET_ISAKMP_NOTIFY_MSG_TYPE(p->p);
LOG_DBG((LOG_EXCHANGE, 10,
"ipsec_responder: got NOTIFY of type %s",
constant_name(isakmp_notify_cst, type)));
switch (type) {
case IPSEC_NOTIFY_INITIAL_CONTACT:
/* Handled by leftover logic. */
break;
case ISAKMP_NOTIFY_STATUS_DPD_R_U_THERE:
case ISAKMP_NOTIFY_STATUS_DPD_R_U_THERE_ACK:
dpd_handle_notify(msg, p);
break;
default:
p->flags |= PL_MARK;
break;
}
}
/*
* If any DELETEs are in here, let the logic of leftover
* payloads deal with them.
*/
return 0;
case IKE_EXCH_QUICK_MODE:
script = ike_quick_mode_responder;
break;
default:
message_drop(msg, ISAKMP_NOTIFY_UNSUPPORTED_EXCHANGE_TYPE,
0, 1, 0);
return -1;
}
/* Run the script code for this step. */
if (script)
return script[exchange->step] (msg);
/*
* XXX So far we don't accept any proposals for exchanges we don't
* support.
*/
if (payload_first(msg, ISAKMP_PAYLOAD_SA)) {
message_drop(msg, ISAKMP_NOTIFY_NO_PROPOSAL_CHOSEN, 0, 1, 0);
return -1;
}
return 0;
}
static enum hashes
from_ike_hash(u_int16_t hash)
{
switch (hash) {
case IKE_HASH_MD5:
return HASH_MD5;
case IKE_HASH_SHA:
return HASH_SHA1;
case IKE_HASH_SHA2_256:
return HASH_SHA2_256;
case IKE_HASH_SHA2_384:
return HASH_SHA2_384;
case IKE_HASH_SHA2_512:
return HASH_SHA2_512;
}
return -1;
}
static enum transform
from_ike_crypto(u_int16_t crypto)
{
/* Coincidentally this is the null operation :-) */
return crypto;
}
/*
* Find out whether the attribute of type TYPE with a LEN length value
* pointed to by VALUE is incompatible with what we can handle.
* VMSG is a pointer to the current message.
*/
int
ipsec_is_attribute_incompatible(u_int16_t type, u_int8_t *value, u_int16_t len,
void *vmsg)
{
struct message *msg = vmsg;
u_int16_t dv = decode_16(value);
if (msg->exchange->phase == 1) {
switch (type) {
case IKE_ATTR_ENCRYPTION_ALGORITHM:
return !crypto_get(from_ike_crypto(dv));
case IKE_ATTR_HASH_ALGORITHM:
return !hash_get(from_ike_hash(dv));
case IKE_ATTR_AUTHENTICATION_METHOD:
return !ike_auth_get(dv);
case IKE_ATTR_GROUP_DESCRIPTION:
return (dv < IKE_GROUP_DESC_MODP_768 ||
dv > IKE_GROUP_DESC_MODP_1536) &&
(dv < IKE_GROUP_DESC_MODP_2048 ||
dv > IKE_GROUP_DESC_MODP_8192);
case IKE_ATTR_GROUP_TYPE:
return 1;
case IKE_ATTR_GROUP_PRIME:
return 1;
case IKE_ATTR_GROUP_GENERATOR_1:
return 1;
case IKE_ATTR_GROUP_GENERATOR_2:
return 1;
case IKE_ATTR_GROUP_CURVE_A:
return 1;
case IKE_ATTR_GROUP_CURVE_B:
return 1;
case IKE_ATTR_LIFE_TYPE:
return dv < IKE_DURATION_SECONDS ||
dv > IKE_DURATION_KILOBYTES;
case IKE_ATTR_LIFE_DURATION:
return len != 2 && len != 4;
case IKE_ATTR_PRF:
return 1;
case IKE_ATTR_KEY_LENGTH:
/*
* Our crypto routines only allows key-lengths which
* are multiples of an octet.
*/
return dv % 8 != 0;
case IKE_ATTR_FIELD_SIZE:
return 1;
case IKE_ATTR_GROUP_ORDER:
return 1;
}
} else {
switch (type) {
case IPSEC_ATTR_SA_LIFE_TYPE:
return dv < IPSEC_DURATION_SECONDS ||
dv > IPSEC_DURATION_KILOBYTES;
case IPSEC_ATTR_SA_LIFE_DURATION:
return len != 2 && len != 4;
case IPSEC_ATTR_GROUP_DESCRIPTION:
return (dv < IKE_GROUP_DESC_MODP_768 ||
dv > IKE_GROUP_DESC_MODP_1536) &&
(dv < IKE_GROUP_DESC_MODP_2048 ||
IKE_GROUP_DESC_MODP_8192 < dv);
case IPSEC_ATTR_ENCAPSULATION_MODE:
return dv != IPSEC_ENCAP_TUNNEL &&
dv != IPSEC_ENCAP_TRANSPORT &&
dv != IPSEC_ENCAP_UDP_ENCAP_TUNNEL &&
dv != IPSEC_ENCAP_UDP_ENCAP_TRANSPORT &&
dv != IPSEC_ENCAP_UDP_ENCAP_TUNNEL_DRAFT &&
dv != IPSEC_ENCAP_UDP_ENCAP_TRANSPORT_DRAFT;
case IPSEC_ATTR_AUTHENTICATION_ALGORITHM:
return dv < IPSEC_AUTH_HMAC_MD5 ||
dv > IPSEC_AUTH_HMAC_RIPEMD;
case IPSEC_ATTR_KEY_LENGTH:
/*
* XXX Blowfish needs '0'. Others appear to disregard
* this attr?
*/
return 0;
case IPSEC_ATTR_KEY_ROUNDS:
return 1;
case IPSEC_ATTR_COMPRESS_DICTIONARY_SIZE:
return 1;
case IPSEC_ATTR_COMPRESS_PRIVATE_ALGORITHM:
return 1;
case IPSEC_ATTR_ECN_TUNNEL:
return 1;
}
}
/* XXX Silence gcc. */
return 1;
}
/*
* Log the attribute of TYPE with a LEN length value pointed to by VALUE
* in human-readable form. VMSG is a pointer to the current message.
*/
int
ipsec_debug_attribute(u_int16_t type, u_int8_t *value, u_int16_t len,
void *vmsg)
{
struct message *msg = vmsg;
char val[20];
/* XXX Transient solution. */
if (len == 2)
snprintf(val, sizeof val, "%d", decode_16(value));
else if (len == 4)
snprintf(val, sizeof val, "%d", decode_32(value));
else
snprintf(val, sizeof val, "unrepresentable");
LOG_DBG((LOG_MESSAGE, 50, "Attribute %s value %s",
constant_name(msg->exchange->phase == 1 ? ike_attr_cst :
ipsec_attr_cst, type), val));
return 0;
}
/*
* Decode the attribute of type TYPE with a LEN length value pointed to by
* VALUE. VIDA is a pointer to a context structure where we can find the
* current message, SA and protocol.
*/
int
ipsec_decode_attribute(u_int16_t type, u_int8_t *value, u_int16_t len,
void *vida)
{
struct ipsec_decode_arg *ida = vida;
struct message *msg = ida->msg;
struct sa *sa = ida->sa;
struct ipsec_sa *isa = sa->data;
struct proto *proto = ida->proto;
struct ipsec_proto *iproto = proto->data;
struct exchange *exchange = msg->exchange;
struct ipsec_exch *ie = exchange->data;
static int lifetype = 0;
if (exchange->phase == 1) {
switch (type) {
case IKE_ATTR_ENCRYPTION_ALGORITHM:
/* XXX Errors possible? */
exchange->crypto = crypto_get(from_ike_crypto(
decode_16(value)));
break;
case IKE_ATTR_HASH_ALGORITHM:
/* XXX Errors possible? */
ie->hash = hash_get(from_ike_hash(decode_16(value)));
break;
case IKE_ATTR_AUTHENTICATION_METHOD:
/* XXX Errors possible? */
ie->ike_auth = ike_auth_get(decode_16(value));
break;
case IKE_ATTR_GROUP_DESCRIPTION:
isa->group_desc = decode_16(value);
break;
case IKE_ATTR_GROUP_TYPE:
break;
case IKE_ATTR_GROUP_PRIME:
break;
case IKE_ATTR_GROUP_GENERATOR_1:
break;
case IKE_ATTR_GROUP_GENERATOR_2:
break;
case IKE_ATTR_GROUP_CURVE_A:
break;
case IKE_ATTR_GROUP_CURVE_B:
break;
case IKE_ATTR_LIFE_TYPE:
lifetype = decode_16(value);
return 0;
case IKE_ATTR_LIFE_DURATION:
switch (lifetype) {
case IKE_DURATION_SECONDS:
switch (len) {
case 2:
sa->seconds = decode_16(value);
break;
case 4:
sa->seconds = decode_32(value);
break;
default:
log_print("ipsec_decode_attribute: "
"unreasonable lifetime");
}
break;
case IKE_DURATION_KILOBYTES:
switch (len) {
case 2:
sa->kilobytes = decode_16(value);
break;
case 4:
sa->kilobytes = decode_32(value);
break;
default:
log_print("ipsec_decode_attribute: "
"unreasonable lifetime");
}
break;
default:
log_print("ipsec_decode_attribute: unknown "
"lifetime type");
}
break;
case IKE_ATTR_PRF:
break;
case IKE_ATTR_KEY_LENGTH:
exchange->key_length = decode_16(value) / 8;
break;
case IKE_ATTR_FIELD_SIZE:
break;
case IKE_ATTR_GROUP_ORDER:
break;
}
} else {
switch (type) {
case IPSEC_ATTR_SA_LIFE_TYPE:
lifetype = decode_16(value);
return 0;
case IPSEC_ATTR_SA_LIFE_DURATION:
switch (lifetype) {
case IPSEC_DURATION_SECONDS:
switch (len) {
case 2:
sa->seconds = decode_16(value);
break;
case 4:
sa->seconds = decode_32(value);
break;
default:
log_print("ipsec_decode_attribute: "
"unreasonable lifetime");
}
break;
case IPSEC_DURATION_KILOBYTES:
switch (len) {
case 2:
sa->kilobytes = decode_16(value);
break;
case 4:
sa->kilobytes = decode_32(value);
break;
default:
log_print("ipsec_decode_attribute: "
"unreasonable lifetime");
}
break;
default:
log_print("ipsec_decode_attribute: unknown "
"lifetime type");
}
break;
case IPSEC_ATTR_GROUP_DESCRIPTION:
isa->group_desc = decode_16(value);
break;
case IPSEC_ATTR_ENCAPSULATION_MODE:
/*
* XXX Multiple protocols must have same
* encapsulation mode, no?
*/
iproto->encap_mode = decode_16(value);
break;
case IPSEC_ATTR_AUTHENTICATION_ALGORITHM:
iproto->auth = decode_16(value);
break;
case IPSEC_ATTR_KEY_LENGTH:
iproto->keylen = decode_16(value);
break;
case IPSEC_ATTR_KEY_ROUNDS:
iproto->keyrounds = decode_16(value);
break;
case IPSEC_ATTR_COMPRESS_DICTIONARY_SIZE:
break;
case IPSEC_ATTR_COMPRESS_PRIVATE_ALGORITHM:
break;
case IPSEC_ATTR_ECN_TUNNEL:
break;
}
}
lifetype = 0;
return 0;
}
/*
* Walk over the attributes of the transform payload found in BUF, and
* fill out the fields of the SA attached to MSG. Also mark the SA as
* processed.
*/
void
ipsec_decode_transform(struct message *msg, struct sa *sa, struct proto *proto,
u_int8_t *buf)
{
struct ipsec_exch *ie = msg->exchange->data;
struct ipsec_decode_arg ida;
LOG_DBG((LOG_MISC, 20, "ipsec_decode_transform: transform %d chosen",
GET_ISAKMP_TRANSFORM_NO(buf)));
ida.msg = msg;
ida.sa = sa;
ida.proto = proto;
/* The default IKE lifetime is 8 hours. */
if (sa->phase == 1)
sa->seconds = 28800;
/* Extract the attributes and stuff them into the SA. */
attribute_map(buf + ISAKMP_TRANSFORM_SA_ATTRS_OFF,
GET_ISAKMP_GEN_LENGTH(buf) - ISAKMP_TRANSFORM_SA_ATTRS_OFF,
ipsec_decode_attribute, &ida);
/*
* If no pseudo-random function was negotiated, it's HMAC.
* XXX As PRF_HMAC currently is zero, this is a no-op.
*/
if (!ie->prf_type)
ie->prf_type = PRF_HMAC;
}
/*
* Delete the IPsec SA represented by the INCOMING direction in protocol PROTO
* of the IKE security association SA.
*/
static void
ipsec_delete_spi(struct sa *sa, struct proto *proto, int incoming)
{
if (sa->phase == 1)
return;
/*
* If the SA was not replaced and was not one acquired through the
* kernel (ACQUIRE message), remove the flow associated with it.
* We ignore any errors from the disabling of the flow.
*/
if (sa->flags & SA_FLAG_READY && !(sa->flags & SA_FLAG_ONDEMAND ||
sa->flags & SA_FLAG_REPLACED || acquire_only ||
conf_get_str("General", "Acquire-Only")))
pf_key_v2_disable_sa(sa, incoming);
/* XXX Error handling? Is it interesting? */
pf_key_v2_delete_spi(sa, proto, incoming);
}
/*
* Store BUF into the g^x entry of the exchange that message MSG belongs to.
* PEER is non-zero when the value is our peer's, and zero when it is ours.
*/
static int
ipsec_g_x(struct message *msg, int peer, u_int8_t *buf)
{
struct exchange *exchange = msg->exchange;
struct ipsec_exch *ie = exchange->data;
u_int8_t **g_x;
int initiator = exchange->initiator ^ peer;
char header[32];
g_x = initiator ? &ie->g_xi : &ie->g_xr;
*g_x = malloc(ie->g_x_len);
if (!*g_x) {
log_error("ipsec_g_x: malloc (%lu) failed",
(unsigned long)ie->g_x_len);
return -1;
}
memcpy(*g_x, buf, ie->g_x_len);
snprintf(header, sizeof header, "ipsec_g_x: g^x%c",
initiator ? 'i' : 'r');
LOG_DBG_BUF((LOG_MISC, 80, header, *g_x, ie->g_x_len));
return 0;
}
/* Generate our DH value. */
int
ipsec_gen_g_x(struct message *msg)
{
struct exchange *exchange = msg->exchange;
struct ipsec_exch *ie = exchange->data;
u_int8_t *buf;
buf = malloc(ISAKMP_KE_SZ + ie->g_x_len);
if (!buf) {
log_error("ipsec_gen_g_x: malloc (%lu) failed",
ISAKMP_KE_SZ + (unsigned long)ie->g_x_len);
return -1;
}
if (message_add_payload(msg, ISAKMP_PAYLOAD_KEY_EXCH, buf,
ISAKMP_KE_SZ + ie->g_x_len, 1)) {
free(buf);
return -1;
}
if (dh_create_exchange(ie->group, buf + ISAKMP_KE_DATA_OFF)) {
log_print("ipsec_gen_g_x: dh_create_exchange failed");
free(buf);
return -1;
}
return ipsec_g_x(msg, 0, buf + ISAKMP_KE_DATA_OFF);
}
/* Save the peer's DH value. */
int
ipsec_save_g_x(struct message *msg)
{
struct exchange *exchange = msg->exchange;
struct ipsec_exch *ie = exchange->data;
struct payload *kep;
kep = payload_first(msg, ISAKMP_PAYLOAD_KEY_EXCH);
kep->flags |= PL_MARK;
ie->g_x_len = GET_ISAKMP_GEN_LENGTH(kep->p) - ISAKMP_KE_DATA_OFF;
/* Check that the given length matches the group's expectancy. */
if (ie->g_x_len != (size_t) dh_getlen(ie->group)) {
/* XXX Is this a good notify type? */
message_drop(msg, ISAKMP_NOTIFY_PAYLOAD_MALFORMED, 0, 1, 0);
return -1;
}
return ipsec_g_x(msg, 1, kep->p + ISAKMP_KE_DATA_OFF);
}
/*
* Get a SPI for PROTO and the transport MSG passed over. Store the
* size where SZ points. NB! A zero return is OK if *SZ is zero.
*/
static u_int8_t *
ipsec_get_spi(size_t *sz, u_int8_t proto, struct message *msg)
{
struct sockaddr *dst, *src;
struct transport *transport = msg->transport;
if (msg->exchange->phase == 1) {
*sz = 0;
return 0;
} else {
/* We are the destination in the SA we want a SPI for. */
transport->vtbl->get_src(transport, &dst);
/* The peer is the source. */
transport->vtbl->get_dst(transport, &src);
return pf_key_v2_get_spi(sz, proto, src, dst,
msg->exchange->seq);
}
}
/*
* We have gotten a payload PAYLOAD of type TYPE, which did not get handled
* by the logic of the exchange MSG takes part in. Now is the time to deal
* with such a payload if we know how to, if we don't, return -1, otherwise
* 0.
*/
int
ipsec_handle_leftover_payload(struct message *msg, u_int8_t type,
struct payload *payload)
{
u_int32_t spisz, nspis;
struct sockaddr *dst;
int reenter = 0;
u_int8_t *spis, proto;
struct sa *sa;
switch (type) {
case ISAKMP_PAYLOAD_DELETE:
proto = GET_ISAKMP_DELETE_PROTO(payload->p);
nspis = GET_ISAKMP_DELETE_NSPIS(payload->p);
spisz = GET_ISAKMP_DELETE_SPI_SZ(payload->p);
if (nspis == 0) {
LOG_DBG((LOG_SA, 60, "ipsec_handle_leftover_payload: "
"message specified zero SPIs, ignoring"));
return -1;
}
/* verify proper SPI size */
if ((proto == ISAKMP_PROTO_ISAKMP &&
spisz != ISAKMP_HDR_COOKIES_LEN) ||
(proto != ISAKMP_PROTO_ISAKMP && spisz != sizeof(u_int32_t))) {
log_print("ipsec_handle_leftover_payload: invalid SPI "
"size %d for proto %d in DELETE payload",
spisz, proto);
return -1;
}
spis = (u_int8_t *) calloc(nspis, spisz);
if (!spis) {
log_error("ipsec_handle_leftover_payload: malloc "
"(%d) failed", nspis * spisz);
return -1;
}
/* extract SPI and get dst address */
memcpy(spis, payload->p + ISAKMP_DELETE_SPI_OFF, nspis * spisz);
msg->transport->vtbl->get_dst(msg->transport, &dst);
ipsec_delete_spi_list(dst, proto, spis, nspis, "DELETE");
free(spis);
payload->flags |= PL_MARK;
return 0;
case ISAKMP_PAYLOAD_NOTIFY:
switch (GET_ISAKMP_NOTIFY_MSG_TYPE(payload->p)) {
case IPSEC_NOTIFY_INITIAL_CONTACT:
/*
* Permit INITIAL-CONTACT if
* - this is not an AGGRESSIVE mode exchange
* - it is protected by an ISAKMP SA
*
* XXX Instead of the first condition above, we could
* XXX permit this only for phase 2. In the last
* XXX packet of main-mode, this payload, while
* XXX encrypted, is not part of the hash digest. As
* XXX we currently send our own INITIAL-CONTACTs at
* XXX this point, this too would need to be changed.
*/
if (msg->exchange->type == ISAKMP_EXCH_AGGRESSIVE) {
log_print("ipsec_handle_leftover_payload: got "
"INITIAL-CONTACT in AGGRESSIVE mode");
return -1;
}
if ((msg->exchange->flags & EXCHANGE_FLAG_ENCRYPT)
== 0) {
log_print("ipsec_handle_leftover_payload: got "
"INITIAL-CONTACT without ISAKMP SA");
return -1;
}
if ((msg->flags & MSG_AUTHENTICATED) == 0) {
log_print("ipsec_handle_leftover_payload: "
"got unauthenticated INITIAL-CONTACT");
return -1;
}
/*
* Find out who is sending this and then delete every
* SA that is ready. Exchanges will timeout
* themselves and then the non-ready SAs will
* disappear too.
*/
msg->transport->vtbl->get_dst(msg->transport, &dst);
while ((sa = sa_lookup_by_peer(dst, SA_LEN(dst), 0)) != 0) {
/*
* Don't delete the current SA -- we received
* the notification over it, so it's obviously
* still active. We temporarily need to remove
* the SA from the list to avoid an endless
* loop, but keep a reference so it won't
* disappear meanwhile.
*/
if (sa == msg->isakmp_sa) {
sa_reference(sa);
sa_remove(sa);
reenter = 1;
continue;
}
LOG_DBG((LOG_SA, 30,
"ipsec_handle_leftover_payload: "
"INITIAL-CONTACT made us delete SA %p",
sa));
sa_delete(sa, 0);
}
if (reenter) {
sa_enter(msg->isakmp_sa);
sa_release(msg->isakmp_sa);
}
payload->flags |= PL_MARK;
return 0;
}
}
return -1;
}
/* Return the encryption keylength in octets of the ESP protocol PROTO. */
int
ipsec_esp_enckeylength(struct proto *proto)
{
struct ipsec_proto *iproto = proto->data;
/* Compute the keylength to use. */
switch (proto->id) {
case IPSEC_ESP_DES:
case IPSEC_ESP_DES_IV32:
case IPSEC_ESP_DES_IV64:
return 8;
case IPSEC_ESP_3DES:
return 24;
case IPSEC_ESP_CAST:
if (!iproto->keylen)
return 16;
return iproto->keylen / 8;
case IPSEC_ESP_AES_128_CTR:
return 20;
case IPSEC_ESP_AES:
if (!iproto->keylen)
return 16;
/* FALLTHROUGH */
default:
return iproto->keylen / 8;
}
}
/* Return the authentication keylength in octets of the ESP protocol PROTO. */
int
ipsec_esp_authkeylength(struct proto *proto)
{
struct ipsec_proto *iproto = proto->data;
switch (iproto->auth) {
case IPSEC_AUTH_HMAC_MD5:
return 16;
case IPSEC_AUTH_HMAC_SHA:
case IPSEC_AUTH_HMAC_RIPEMD:
return 20;
case IPSEC_AUTH_HMAC_SHA2_256:
return 32;
case IPSEC_AUTH_HMAC_SHA2_384:
return 48;
case IPSEC_AUTH_HMAC_SHA2_512:
return 64;
default:
return 0;
}
}
/* Return the authentication keylength in octets of the AH protocol PROTO. */
int
ipsec_ah_keylength(struct proto *proto)
{
switch (proto->id) {
case IPSEC_AH_MD5:
return 16;
case IPSEC_AH_SHA:
case IPSEC_AH_RIPEMD:
return 20;
case IPSEC_AH_SHA2_256:
return 32;
case IPSEC_AH_SHA2_384:
return 48;
case IPSEC_AH_SHA2_512:
return 64;
default:
return -1;
}
}
/* Return the total keymaterial length of the protocol PROTO. */
int
ipsec_keymat_length(struct proto *proto)
{
switch (proto->proto) {
case IPSEC_PROTO_IPSEC_ESP:
return ipsec_esp_enckeylength(proto)
+ ipsec_esp_authkeylength(proto);
case IPSEC_PROTO_IPSEC_AH:
return ipsec_ah_keylength(proto);
default:
return -1;
}
}
/* Helper function for ipsec_get_id(). */
static int
ipsec_get_proto_port(char *section, u_int8_t *tproto, u_int16_t *port)
{
struct protoent *pe = NULL;
struct servent *se;
char *pstr;
pstr = conf_get_str(section, "Protocol");
if (!pstr) {
*tproto = 0;
return 0;
}
*tproto = (u_int8_t)atoi(pstr);
if (!*tproto) {
pe = getprotobyname(pstr);
if (pe)
*tproto = pe->p_proto;
}
if (!*tproto) {
log_print("ipsec_get_proto_port: protocol \"%s\" unknown",
pstr);
return -1;
}
pstr = conf_get_str(section, "Port");
if (!pstr)
return 0;
*port = (u_int16_t)atoi(pstr);
if (!*port) {
se = getservbyname(pstr,
pe ? pe->p_name : (pstr ? pstr : NULL));
if (se)
*port = ntohs(se->s_port);
}
if (!*port) {
log_print("ipsec_get_proto_port: port \"%s\" unknown",
pstr);
return -1;
}
return 0;
}
/*
* Out of a named section SECTION in the configuration file find out
* the network address and mask as well as the ID type. Put the info
* in the areas pointed to by ADDR, MASK, TPROTO, PORT, and ID respectively.
* Return 0 on success and -1 on failure.
*/
int
ipsec_get_id(char *section, int *id, struct sockaddr **addr,
struct sockaddr **mask, u_int8_t *tproto, u_int16_t *port)
{
char *type, *address, *netmask;
sa_family_t af = 0;
type = conf_get_str(section, "ID-type");
if (!type) {
log_print("ipsec_get_id: section %s has no \"ID-type\" tag",
section);
return -1;
}
*id = constant_value(ipsec_id_cst, type);
switch (*id) {
case IPSEC_ID_IPV4_ADDR:
case IPSEC_ID_IPV4_ADDR_SUBNET:
af = AF_INET;
break;
case IPSEC_ID_IPV6_ADDR:
case IPSEC_ID_IPV6_ADDR_SUBNET:
af = AF_INET6;
break;
}
switch (*id) {
case IPSEC_ID_IPV4_ADDR:
case IPSEC_ID_IPV6_ADDR: {
int ret;
address = conf_get_str(section, "Address");
if (!address) {
log_print("ipsec_get_id: section %s has no "
"\"Address\" tag", section);
return -1;
}
if (text2sockaddr(address, NULL, addr, af, 0)) {
log_print("ipsec_get_id: invalid address %s in "
"section %s", address, section);
return -1;
}
ret = ipsec_get_proto_port(section, tproto, port);
if (ret < 0)
free(*addr);
return ret;
}
#ifdef notyet
case IPSEC_ID_FQDN:
return -1;
case IPSEC_ID_USER_FQDN:
return -1;
#endif
case IPSEC_ID_IPV4_ADDR_SUBNET:
case IPSEC_ID_IPV6_ADDR_SUBNET: {
int ret;
address = conf_get_str(section, "Network");
if (!address) {
log_print("ipsec_get_id: section %s has no "
"\"Network\" tag", section);
return -1;
}
if (text2sockaddr(address, NULL, addr, af, 0)) {
log_print("ipsec_get_id: invalid section %s "
"network %s", section, address);
return -1;
}
netmask = conf_get_str(section, "Netmask");
if (!netmask) {
log_print("ipsec_get_id: section %s has no "
"\"Netmask\" tag", section);
free(*addr);
return -1;
}
if (text2sockaddr(netmask, NULL, mask, af, 1)) {
log_print("ipsec_get_id: invalid section %s "
"network %s", section, netmask);
free(*addr);
return -1;
}
ret = ipsec_get_proto_port(section, tproto, port);
if (ret < 0) {
free(*mask);
free(*addr);
}
return ret;
}
#ifdef notyet
case IPSEC_ID_IPV4_RANGE:
return -1;
case IPSEC_ID_IPV6_RANGE:
return -1;
case IPSEC_ID_DER_ASN1_DN:
return -1;
case IPSEC_ID_DER_ASN1_GN:
return -1;
case IPSEC_ID_KEY_ID:
return -1;
#endif
default:
log_print("ipsec_get_id: unknown ID type \"%s\" in "
"section %s", type, section);
return -1;
}
return 0;
}
/*
* XXX I rather want this function to return a status code, and fail if
* we cannot fit the information in the supplied buffer.
*/
static void
ipsec_decode_id(char *buf, size_t size, u_int8_t *id, size_t id_len,
int isakmpform)
{
int id_type;
char *addr = 0, *mask = 0;
u_int32_t *idp;
if (id) {
if (!isakmpform) {
/*
* Exchanges and SAs dont carry the IDs in ISAKMP
* form.
*/
id -= ISAKMP_GEN_SZ;
id_len += ISAKMP_GEN_SZ;
}
id_type = GET_ISAKMP_ID_TYPE(id);
idp = (u_int32_t *) (id + ISAKMP_ID_DATA_OFF);
switch (id_type) {
case IPSEC_ID_IPV4_ADDR:
util_ntoa(&addr, AF_INET, id + ISAKMP_ID_DATA_OFF);
snprintf(buf, size, "%s", addr);
break;
case IPSEC_ID_IPV4_ADDR_SUBNET:
util_ntoa(&addr, AF_INET, id + ISAKMP_ID_DATA_OFF);
util_ntoa(&mask, AF_INET, id + ISAKMP_ID_DATA_OFF + 4);
snprintf(buf, size, "%s/%s", addr, mask);
break;
case IPSEC_ID_IPV6_ADDR:
util_ntoa(&addr, AF_INET6, id + ISAKMP_ID_DATA_OFF);
snprintf(buf, size, "%s", addr);
break;
case IPSEC_ID_IPV6_ADDR_SUBNET:
util_ntoa(&addr, AF_INET6, id + ISAKMP_ID_DATA_OFF);
util_ntoa(&mask, AF_INET6, id + ISAKMP_ID_DATA_OFF +
sizeof(struct in6_addr));
snprintf(buf, size, "%s/%s", addr, mask);
break;
case IPSEC_ID_FQDN:
case IPSEC_ID_USER_FQDN:
/* String is not NUL terminated, be careful */
id_len -= ISAKMP_ID_DATA_OFF;
id_len = MIN(id_len, size - 1);
memcpy(buf, id + ISAKMP_ID_DATA_OFF, id_len);
buf[id_len] = '\0';
break;
case IPSEC_ID_DER_ASN1_DN:
addr = x509_DN_string(id + ISAKMP_ID_DATA_OFF,
id_len - ISAKMP_ID_DATA_OFF);
if (!addr) {
snprintf(buf, size, "unparsable ASN1 DN ID");
return;
}
strlcpy(buf, addr, size);
break;
default:
snprintf(buf, size, "<id type unknown: %x>", id_type);
break;
}
} else
snprintf(buf, size, "<no ipsec id>");
free(addr);
free(mask);
}
char *
ipsec_decode_ids(char *fmt, u_int8_t *id1, size_t id1_len, u_int8_t *id2,
size_t id2_len, int isakmpform)
{
static char result[1024];
char s_id1[256], s_id2[256];
ipsec_decode_id(s_id1, sizeof s_id1, id1, id1_len, isakmpform);
ipsec_decode_id(s_id2, sizeof s_id2, id2, id2_len, isakmpform);
snprintf(result, sizeof result, fmt, s_id1, s_id2);
return result;
}
/*
* Out of a named section SECTION in the configuration file build an
* ISAKMP ID payload. Ths payload size should be stashed in SZ.
* The caller is responsible for freeing the payload.
*/
u_int8_t *
ipsec_build_id(char *section, size_t *sz)
{
struct sockaddr *addr, *mask;
u_int8_t *p;
int id, subnet = 0;
u_int8_t tproto = 0;
u_int16_t port = 0;
if (ipsec_get_id(section, &id, &addr, &mask, &tproto, &port))
return 0;
if (id == IPSEC_ID_IPV4_ADDR_SUBNET || id == IPSEC_ID_IPV6_ADDR_SUBNET)
subnet = 1;
*sz = ISAKMP_ID_SZ + sockaddr_addrlen(addr);
if (subnet)
*sz += sockaddr_addrlen(mask);
p = malloc(*sz);
if (!p) {
log_print("ipsec_build_id: malloc(%lu) failed",
(unsigned long)*sz);
if (subnet)
free(mask);
free(addr);
return 0;
}
SET_ISAKMP_ID_TYPE(p, id);
SET_ISAKMP_ID_DOI_DATA(p, (unsigned char *)"\000\000\000");
memcpy(p + ISAKMP_ID_DATA_OFF, sockaddr_addrdata(addr),
sockaddr_addrlen(addr));
if (subnet)
memcpy(p + ISAKMP_ID_DATA_OFF + sockaddr_addrlen(addr),
sockaddr_addrdata(mask), sockaddr_addrlen(mask));
SET_IPSEC_ID_PROTO(p + ISAKMP_ID_DOI_DATA_OFF, tproto);
SET_IPSEC_ID_PORT(p + ISAKMP_ID_DOI_DATA_OFF, port);
if (subnet)
free(mask);
free(addr);
return p;
}
/*
* copy an ISAKMPD id
*/
int
ipsec_clone_id(u_int8_t **did, size_t *did_len, u_int8_t *id, size_t id_len)
{
free(*did);
if (!id_len || !id) {
*did = 0;
*did_len = 0;
return 0;
}
*did = malloc(id_len);
if (!*did) {
*did_len = 0;
log_error("ipsec_clone_id: malloc(%lu) failed",
(unsigned long)id_len);
return -1;
}
*did_len = id_len;
memcpy(*did, id, id_len);
return 0;
}
/*
* IPsec-specific PROTO initializations. SECTION is only set if we are the
* initiator thus only usable there.
* XXX I want to fix this later.
*/
void
ipsec_proto_init(struct proto *proto, char *section)
{
struct ipsec_proto *iproto = proto->data;
if (proto->sa->phase == 2)
iproto->replay_window = section ? conf_get_num(section,
"ReplayWindow", DEFAULT_REPLAY_WINDOW) :
DEFAULT_REPLAY_WINDOW;
}
/*
* Add a notification payload of type INITIAL CONTACT to MSG if this is
* the first contact we have made to our peer.
*/
int
ipsec_initial_contact(struct message *msg)
{
u_int8_t *buf;
if (ipsec_contacted(msg))
return 0;
buf = malloc(ISAKMP_NOTIFY_SZ + ISAKMP_HDR_COOKIES_LEN);
if (!buf) {
log_error("ike_phase_1_initial_contact: malloc (%d) failed",
ISAKMP_NOTIFY_SZ + ISAKMP_HDR_COOKIES_LEN);
return -1;
}
SET_ISAKMP_NOTIFY_DOI(buf, IPSEC_DOI_IPSEC);
SET_ISAKMP_NOTIFY_PROTO(buf, ISAKMP_PROTO_ISAKMP);
SET_ISAKMP_NOTIFY_SPI_SZ(buf, ISAKMP_HDR_COOKIES_LEN);
SET_ISAKMP_NOTIFY_MSG_TYPE(buf, IPSEC_NOTIFY_INITIAL_CONTACT);
memcpy(buf + ISAKMP_NOTIFY_SPI_OFF, msg->isakmp_sa->cookies,
ISAKMP_HDR_COOKIES_LEN);
if (message_add_payload(msg, ISAKMP_PAYLOAD_NOTIFY, buf,
ISAKMP_NOTIFY_SZ + ISAKMP_HDR_COOKIES_LEN, 1)) {
free(buf);
return -1;
}
return ipsec_add_contact(msg);
}
/*
* Compare the two contacts pointed to by A and B. Return negative if
* *A < *B, 0 if they are equal, and positive if *A is the largest of them.
*/
static int
addr_cmp(const void *a, const void *b)
{
const struct contact *x = a, *y = b;
int minlen = MIN(x->len, y->len);
int rv = memcmp(x->addr, y->addr, minlen);
return rv ? rv : (x->len - y->len);
}
/*
* Add the peer that MSG is bound to as an address we don't want to send
* INITIAL CONTACT too from now on. Do not call this function with a
* specific address duplicate times. We want fast lookup, speed of insertion
* is unimportant, if this is to scale.
*/
static int
ipsec_add_contact(struct message *msg)
{
struct contact *new_contacts;
struct sockaddr *dst, *addr;
int cnt;
if (contact_cnt == contact_limit) {
cnt = contact_limit ? 2 * contact_limit : 64;
new_contacts = realloc(contacts, cnt * sizeof contacts[0]);
if (!new_contacts) {
log_error("ipsec_add_contact: "
"realloc (%p, %lu) failed", contacts,
cnt * (unsigned long) sizeof contacts[0]);
return -1;
}
contact_limit = cnt;
contacts = new_contacts;
}
msg->transport->vtbl->get_dst(msg->transport, &dst);
addr = malloc(SA_LEN(dst));
if (!addr) {
log_error("ipsec_add_contact: malloc (%lu) failed",
(unsigned long)SA_LEN(dst));
return -1;
}
memcpy(addr, dst, SA_LEN(dst));
contacts[contact_cnt].addr = addr;
contacts[contact_cnt++].len = SA_LEN(dst);
/*
* XXX There are better algorithms for already mostly-sorted data like
* this, but only qsort is standard. I will someday do this inline.
*/
qsort(contacts, contact_cnt, sizeof *contacts, addr_cmp);
return 0;
}
/* Return true if the recipient of MSG has already been contacted. */
static int
ipsec_contacted(struct message *msg)
{
struct contact contact;
msg->transport->vtbl->get_dst(msg->transport, &contact.addr);
contact.len = SA_LEN(contact.addr);
return contacts ? (bsearch(&contact, contacts, contact_cnt,
sizeof *contacts, addr_cmp) != 0) : 0;
}
/* Add a HASH for to MSG. */
u_int8_t *
ipsec_add_hash_payload(struct message *msg, size_t hashsize)
{
u_int8_t *buf;
buf = malloc(ISAKMP_HASH_SZ + hashsize);
if (!buf) {
log_error("ipsec_add_hash_payload: malloc (%lu) failed",
ISAKMP_HASH_SZ + (unsigned long) hashsize);
return 0;
}
if (message_add_payload(msg, ISAKMP_PAYLOAD_HASH, buf,
ISAKMP_HASH_SZ + hashsize, 1)) {
free(buf);
return 0;
}
return buf;
}
/* Fill in the HASH payload of MSG. */
int
ipsec_fill_in_hash(struct message *msg)
{
struct exchange *exchange = msg->exchange;
struct sa *isakmp_sa = msg->isakmp_sa;
struct ipsec_sa *isa = isakmp_sa->data;
struct hash *hash = hash_get(isa->hash);
struct prf *prf;
struct payload *payload;
u_int8_t *buf;
u_int32_t i;
char header[80];
/* If no SKEYID_a, we need not do anything. */
if (!isa->skeyid_a)
return 0;
payload = payload_first(msg, ISAKMP_PAYLOAD_HASH);
if (!payload) {
log_print("ipsec_fill_in_hash: no HASH payload found");
return -1;
}
buf = payload->p;
/* Allocate the prf and start calculating our HASH(1). */
LOG_DBG_BUF((LOG_MISC, 90, "ipsec_fill_in_hash: SKEYID_a",
isa->skeyid_a, isa->skeyid_len));
prf = prf_alloc(isa->prf_type, hash->type, isa->skeyid_a,
isa->skeyid_len);
if (!prf)
return -1;
prf->Init(prf->prfctx);
LOG_DBG_BUF((LOG_MISC, 90, "ipsec_fill_in_hash: message_id",
exchange->message_id, ISAKMP_HDR_MESSAGE_ID_LEN));
prf->Update(prf->prfctx, exchange->message_id,
ISAKMP_HDR_MESSAGE_ID_LEN);
/* Loop over all payloads after HASH(1). */
for (i = 2; i < msg->iovlen; i++) {
/* XXX Misleading payload type printouts. */
snprintf(header, sizeof header,
"ipsec_fill_in_hash: payload %d after HASH(1)", i - 1);
LOG_DBG_BUF((LOG_MISC, 90, header, msg->iov[i].iov_base,
msg->iov[i].iov_len));
prf->Update(prf->prfctx, msg->iov[i].iov_base,
msg->iov[i].iov_len);
}
prf->Final(buf + ISAKMP_HASH_DATA_OFF, prf->prfctx);
prf_free(prf);
LOG_DBG_BUF((LOG_MISC, 80, "ipsec_fill_in_hash: HASH(1)", buf +
ISAKMP_HASH_DATA_OFF, hash->hashsize));
return 0;
}
/* Add a HASH payload to MSG, if we have an ISAKMP SA we're protected by. */
static int
ipsec_informational_pre_hook(struct message *msg)
{
struct sa *isakmp_sa = msg->isakmp_sa;
struct ipsec_sa *isa;
struct hash *hash;
if (!isakmp_sa)
return 0;
isa = isakmp_sa->data;
hash = hash_get(isa->hash);
return ipsec_add_hash_payload(msg, hash->hashsize) == 0;
}
/*
* Fill in the HASH payload in MSG, if we have an ISAKMP SA we're protected by.
*/
static int
ipsec_informational_post_hook(struct message *msg)
{
if (!msg->isakmp_sa)
return 0;
return ipsec_fill_in_hash(msg);
}
ssize_t
ipsec_id_size(char *section, u_int8_t *id)
{
char *type, *data;
type = conf_get_str(section, "ID-type");
if (!type) {
log_print("ipsec_id_size: section %s has no \"ID-type\" tag",
section);
return -1;
}
*id = constant_value(ipsec_id_cst, type);
switch (*id) {
case IPSEC_ID_IPV4_ADDR:
return sizeof(struct in_addr);
case IPSEC_ID_IPV4_ADDR_SUBNET:
return 2 * sizeof(struct in_addr);
case IPSEC_ID_IPV6_ADDR:
return sizeof(struct in6_addr);
case IPSEC_ID_IPV6_ADDR_SUBNET:
return 2 * sizeof(struct in6_addr);
case IPSEC_ID_FQDN:
case IPSEC_ID_USER_FQDN:
case IPSEC_ID_KEY_ID:
case IPSEC_ID_DER_ASN1_DN:
case IPSEC_ID_DER_ASN1_GN:
data = conf_get_str(section, "Name");
if (!data) {
log_print("ipsec_id_size: "
"section %s has no \"Name\" tag", section);
return -1;
}
return strlen(data);
}
log_print("ipsec_id_size: unrecognized/unsupported ID-type %d (%s)",
*id, type);
return -1;
}
/*
* Generate a string version of the ID.
*/
char *
ipsec_id_string(u_int8_t *id, size_t id_len)
{
char *buf = 0;
char *addrstr = 0;
size_t len, size;
/*
* XXX Real ugly way of making the offsets correct. Be aware that id
* now will point before the actual buffer and cannot be dereferenced
* without an offset larger than or equal to ISAKM_GEN_SZ.
*/
id -= ISAKMP_GEN_SZ;
/* This is the actual length of the ID data field. */
id_len += ISAKMP_GEN_SZ - ISAKMP_ID_DATA_OFF;
/*
* Conservative allocation.
* XXX I think the ASN1 DN case can be thought through to give a better
* estimate.
*/
size = MAX(sizeof "ipv6/ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff",
sizeof "asn1_dn/" + id_len - ISAKMP_ID_DATA_OFF);
buf = malloc(size);
if (!buf)
/* XXX Log? */
goto fail;
switch (GET_ISAKMP_ID_TYPE(id)) {
case IPSEC_ID_IPV4_ADDR:
if (id_len < sizeof(struct in_addr))
goto fail;
util_ntoa(&addrstr, AF_INET, id + ISAKMP_ID_DATA_OFF);
if (!addrstr)
goto fail;
snprintf(buf, size, "ipv4/%s", addrstr);
break;
case IPSEC_ID_IPV6_ADDR:
if (id_len < sizeof(struct in6_addr))
goto fail;
util_ntoa(&addrstr, AF_INET6, id + ISAKMP_ID_DATA_OFF);
if (!addrstr)
goto fail;
snprintf(buf, size, "ipv6/%s", addrstr);
break;
case IPSEC_ID_FQDN:
case IPSEC_ID_USER_FQDN:
strlcpy(buf, GET_ISAKMP_ID_TYPE(id) == IPSEC_ID_FQDN ?
"fqdn/" : "ufqdn/", size);
len = strlen(buf);
memcpy(buf + len, id + ISAKMP_ID_DATA_OFF, id_len);
*(buf + len + id_len) = '\0';
break;
case IPSEC_ID_DER_ASN1_DN:
strlcpy(buf, "asn1_dn/", size);
len = strlen(buf);
addrstr = x509_DN_string(id + ISAKMP_ID_DATA_OFF,
id_len - ISAKMP_ID_DATA_OFF);
if (!addrstr)
goto fail;
if (size < len + strlen(addrstr) + 1)
goto fail;
strlcpy(buf + len, addrstr, size - len);
break;
default:
/* Unknown type. */
LOG_DBG((LOG_MISC, 10,
"ipsec_id_string: unknown identity type %d\n",
GET_ISAKMP_ID_TYPE(id)));
goto fail;
}
free(addrstr);
return buf;
fail:
free(buf);
free(addrstr);
return 0;
}