linux/net/ipv6/xfrm6_state.c
Masahide NAKAMURA 59fbb3a61e [IPV6] MIP6: Loadable module support for MIPv6.
This patch makes MIPv6 loadable module named "mip6".

Here is a modprobe.conf(5) example to load it automatically
when user application uses XFRM state for MIPv6:

alias xfrm-type-10-43 mip6
alias xfrm-type-10-60 mip6

Some MIPv6 feature is not included by this modular, however,
it should not be affected to other features like either IPsec
or IPv6 with and without the patch.
We may discuss XFRM, MH (RAW socket) and ancillary data/sockopt
separately for future work.

Loadable features:
* MH receiving check (to send ICMP error back)
* RO header parsing and building (i.e. RH2 and HAO in DSTOPTS)
* XFRM policy/state database handling for RO

These are NOT covered as loadable:
* Home Address flags and its rule on source address selection
* XFRM sub policy (depends on its own kernel option)
* XFRM functions to receive RO as IPv6 extension header
* MH sending/receiving through raw socket if user application
  opens it (since raw socket allows to do so)
* RH2 sending as ancillary data
* RH2 operation with setsockopt(2)

Signed-off-by: Masahide NAKAMURA <nakam@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:15:42 -07:00

186 lines
4 KiB
C

/*
* xfrm6_state.c: based on xfrm4_state.c
*
* Authors:
* Mitsuru KANDA @USAGI
* Kazunori MIYAZAWA @USAGI
* Kunihiro Ishiguro <kunihiro@ipinfusion.com>
* IPv6 support
* YOSHIFUJI Hideaki @USAGI
* Split up af-specific portion
*
*/
#include <net/xfrm.h>
#include <linux/pfkeyv2.h>
#include <linux/ipsec.h>
#include <net/ipv6.h>
#include <net/addrconf.h>
static struct xfrm_state_afinfo xfrm6_state_afinfo;
static void
__xfrm6_init_tempsel(struct xfrm_state *x, struct flowi *fl,
struct xfrm_tmpl *tmpl,
xfrm_address_t *daddr, xfrm_address_t *saddr)
{
/* Initialize temporary selector matching only
* to current session. */
ipv6_addr_copy((struct in6_addr *)&x->sel.daddr, &fl->fl6_dst);
ipv6_addr_copy((struct in6_addr *)&x->sel.saddr, &fl->fl6_src);
x->sel.dport = xfrm_flowi_dport(fl);
x->sel.dport_mask = htons(0xffff);
x->sel.sport = xfrm_flowi_sport(fl);
x->sel.sport_mask = htons(0xffff);
x->sel.prefixlen_d = 128;
x->sel.prefixlen_s = 128;
x->sel.proto = fl->proto;
x->sel.ifindex = fl->oif;
x->id = tmpl->id;
if (ipv6_addr_any((struct in6_addr*)&x->id.daddr))
memcpy(&x->id.daddr, daddr, sizeof(x->sel.daddr));
memcpy(&x->props.saddr, &tmpl->saddr, sizeof(x->props.saddr));
if (ipv6_addr_any((struct in6_addr*)&x->props.saddr))
memcpy(&x->props.saddr, saddr, sizeof(x->props.saddr));
x->props.mode = tmpl->mode;
x->props.reqid = tmpl->reqid;
x->props.family = AF_INET6;
}
static int
__xfrm6_state_sort(struct xfrm_state **dst, struct xfrm_state **src, int n)
{
int i;
int j = 0;
/* Rule 1: select IPsec transport except AH */
for (i = 0; i < n; i++) {
if (src[i]->props.mode == XFRM_MODE_TRANSPORT &&
src[i]->id.proto != IPPROTO_AH) {
dst[j++] = src[i];
src[i] = NULL;
}
}
if (j == n)
goto end;
/* Rule 2: select MIPv6 RO or inbound trigger */
#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
for (i = 0; i < n; i++) {
if (src[i] &&
(src[i]->props.mode == XFRM_MODE_ROUTEOPTIMIZATION ||
src[i]->props.mode == XFRM_MODE_IN_TRIGGER)) {
dst[j++] = src[i];
src[i] = NULL;
}
}
if (j == n)
goto end;
#endif
/* Rule 3: select IPsec transport AH */
for (i = 0; i < n; i++) {
if (src[i] &&
src[i]->props.mode == XFRM_MODE_TRANSPORT &&
src[i]->id.proto == IPPROTO_AH) {
dst[j++] = src[i];
src[i] = NULL;
}
}
if (j == n)
goto end;
/* Rule 4: select IPsec tunnel */
for (i = 0; i < n; i++) {
if (src[i] &&
src[i]->props.mode == XFRM_MODE_TUNNEL) {
dst[j++] = src[i];
src[i] = NULL;
}
}
if (likely(j == n))
goto end;
/* Final rule */
for (i = 0; i < n; i++) {
if (src[i]) {
dst[j++] = src[i];
src[i] = NULL;
}
}
end:
return 0;
}
static int
__xfrm6_tmpl_sort(struct xfrm_tmpl **dst, struct xfrm_tmpl **src, int n)
{
int i;
int j = 0;
/* Rule 1: select IPsec transport */
for (i = 0; i < n; i++) {
if (src[i]->mode == XFRM_MODE_TRANSPORT) {
dst[j++] = src[i];
src[i] = NULL;
}
}
if (j == n)
goto end;
/* Rule 2: select MIPv6 RO or inbound trigger */
#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
for (i = 0; i < n; i++) {
if (src[i] &&
(src[i]->mode == XFRM_MODE_ROUTEOPTIMIZATION ||
src[i]->mode == XFRM_MODE_IN_TRIGGER)) {
dst[j++] = src[i];
src[i] = NULL;
}
}
if (j == n)
goto end;
#endif
/* Rule 3: select IPsec tunnel */
for (i = 0; i < n; i++) {
if (src[i] &&
src[i]->mode == XFRM_MODE_TUNNEL) {
dst[j++] = src[i];
src[i] = NULL;
}
}
if (likely(j == n))
goto end;
/* Final rule */
for (i = 0; i < n; i++) {
if (src[i]) {
dst[j++] = src[i];
src[i] = NULL;
}
}
end:
return 0;
}
static struct xfrm_state_afinfo xfrm6_state_afinfo = {
.family = AF_INET6,
.init_tempsel = __xfrm6_init_tempsel,
.tmpl_sort = __xfrm6_tmpl_sort,
.state_sort = __xfrm6_state_sort,
.output = xfrm6_output,
};
void __init xfrm6_state_init(void)
{
xfrm_state_register_afinfo(&xfrm6_state_afinfo);
}
void xfrm6_state_fini(void)
{
xfrm_state_unregister_afinfo(&xfrm6_state_afinfo);
}