static void ila_csum_do_neutral(struct ila_addr *iaddr,
struct ila_params *p)
{
__sum16 *adjust = (__force __sum16 *)&iaddr->ident.v16[3];
__wsum diff, fval;
/* Check if checksum adjust value has been cached */
if (p->locator_match.v64) {
diff = p->csum_diff;
} else {
diff = compute_csum_diff8((__be32 *)iaddr,
(__be32 *)&p->locator);
}
fval = (__force __wsum)(ila_csum_neutral_set(iaddr->ident) ?
~CSUM_NEUTRAL_FLAG : CSUM_NEUTRAL_FLAG);
diff = csum_add(diff, fval);
*adjust = ~csum_fold(csum_add(diff, csum_unfold(*adjust)));
/* Flip the csum-neutral bit. Either we are doing a SIR->ILA
* translation with ILA_CSUM_NEUTRAL_MAP as the csum_method
* and the C-bit is not set, or we are doing an ILA-SIR
* tranlsation and the C-bit is set.
*/
iaddr->ident.csum_neutral ^= 1;
}
void ila_init_saved_csum(struct ila_params *p)
{
if (!p->locator_match.v64)
return;
p->csum_diff = compute_csum_diff8(
(__be32 *)&p->locator_match,
(__be32 *)&p->locator);
}
static __wsum get_csum_diff(struct ipv6hdr *ip6h, struct ila_params *p)
{
struct ila_addr *iaddr = ila_a2i(&ip6h->daddr);
if (p->locator_match.v64)
return p->csum_diff;
else
return compute_csum_diff8((__be32 *)&iaddr->loc,
(__be32 *)&p->locator);
}
static int ila_build_state(struct nlattr *nla,
unsigned int family, const void *cfg,
struct lwtunnel_state **ts,
struct netlink_ext_ack *extack)
{
struct ila_lwt *ilwt;
struct ila_params *p;
struct nlattr *tb[ILA_ATTR_MAX + 1];
struct lwtunnel_state *newts;
const struct fib6_config *cfg6 = cfg;
struct ila_addr *iaddr;
int ret;
if (family != AF_INET6)
return -EINVAL;
if (cfg6->fc_dst_len < 8 * sizeof(struct ila_locator) + 3) {
/* Need to have full locator and at least type field
* included in destination
*/
return -EINVAL;
}
iaddr = (struct ila_addr *)&cfg6->fc_dst;
if (!ila_addr_is_ila(iaddr) || ila_csum_neutral_set(iaddr->ident)) {
/* Don't allow translation for a non-ILA address or checksum
* neutral flag to be set.
*/
return -EINVAL;
}
ret = nla_parse_nested(tb, ILA_ATTR_MAX, nla, ila_nl_policy, extack);
if (ret < 0)
return ret;
if (!tb[ILA_ATTR_LOCATOR])
return -EINVAL;
newts = lwtunnel_state_alloc(sizeof(*ilwt));
if (!newts)
return -ENOMEM;
ilwt = ila_lwt_lwtunnel(newts);
ret = dst_cache_init(&ilwt->dst_cache, GFP_ATOMIC);
if (ret) {
kfree(newts);
return ret;
}
p = ila_params_lwtunnel(newts);
p->locator.v64 = (__force __be64)nla_get_u64(tb[ILA_ATTR_LOCATOR]);
/* Precompute checksum difference for translation since we
* know both the old locator and the new one.
*/
p->locator_match = iaddr->loc;
p->csum_diff = compute_csum_diff8(
(__be32 *)&p->locator_match, (__be32 *)&p->locator);
if (tb[ILA_ATTR_CSUM_MODE])
p->csum_mode = nla_get_u8(tb[ILA_ATTR_CSUM_MODE]);
ila_init_saved_csum(p);
newts->type = LWTUNNEL_ENCAP_ILA;
newts->flags |= LWTUNNEL_STATE_OUTPUT_REDIRECT |
LWTUNNEL_STATE_INPUT_REDIRECT;
if (cfg6->fc_dst_len == 8 * sizeof(struct in6_addr))
ilwt->connected = 1;
*ts = newts;
return 0;
}