1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/errno.h>
4 #include <linux/kernel.h>
5 #include <linux/module.h>
6 #include <linux/skbuff.h>
7 #include <linux/socket.h>
8 #include <linux/types.h>
9 #include <net/checksum.h>
10 #include <net/dst_cache.h>
12 #include <net/ip6_fib.h>
13 #include <net/ip6_route.h>
14 #include <net/lwtunnel.h>
15 #include <net/protocol.h>
16 #include <uapi/linux/ila.h>
21 struct dst_cache dst_cache;
25 static inline struct ila_lwt *ila_lwt_lwtunnel(
26 struct lwtunnel_state *lwt)
28 return (struct ila_lwt *)lwt->data;
31 static inline struct ila_params *ila_params_lwtunnel(
32 struct lwtunnel_state *lwt)
34 return &ila_lwt_lwtunnel(lwt)->p;
37 static int ila_output(struct net *net, struct sock *sk, struct sk_buff *skb)
39 struct dst_entry *orig_dst = skb_dst(skb);
40 struct rt6_info *rt = (struct rt6_info *)orig_dst;
41 struct ila_lwt *ilwt = ila_lwt_lwtunnel(orig_dst->lwtstate);
42 struct dst_entry *dst;
45 if (skb->protocol != htons(ETH_P_IPV6))
48 ila_update_ipv6_locator(skb, ila_params_lwtunnel(orig_dst->lwtstate),
51 if (rt->rt6i_flags & (RTF_GATEWAY | RTF_CACHE)) {
52 /* Already have a next hop address in route, no need for
55 return orig_dst->lwtstate->orig_output(net, sk, skb);
58 dst = dst_cache_get(&ilwt->dst_cache);
60 struct ipv6hdr *ip6h = ipv6_hdr(skb);
63 /* Lookup a route for the new destination. Take into
64 * account that the base route may already have a gateway.
67 memset(&fl6, 0, sizeof(fl6));
68 fl6.flowi6_oif = orig_dst->dev->ifindex;
69 fl6.flowi6_iif = LOOPBACK_IFINDEX;
70 fl6.daddr = *rt6_nexthop((struct rt6_info *)orig_dst,
73 dst = ip6_route_output(net, NULL, &fl6);
80 dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), NULL, 0);
87 dst_cache_set_ip6(&ilwt->dst_cache, dst, &fl6.saddr);
90 skb_dst_set(skb, dst);
91 return dst_output(net, sk, skb);
98 static int ila_input(struct sk_buff *skb)
100 struct dst_entry *dst = skb_dst(skb);
102 if (skb->protocol != htons(ETH_P_IPV6))
105 ila_update_ipv6_locator(skb, ila_params_lwtunnel(dst->lwtstate), false);
107 return dst->lwtstate->orig_input(skb);
114 static const struct nla_policy ila_nl_policy[ILA_ATTR_MAX + 1] = {
115 [ILA_ATTR_LOCATOR] = { .type = NLA_U64, },
116 [ILA_ATTR_CSUM_MODE] = { .type = NLA_U8, },
117 [ILA_ATTR_IDENT_TYPE] = { .type = NLA_U8, },
120 static int ila_build_state(struct nlattr *nla,
121 unsigned int family, const void *cfg,
122 struct lwtunnel_state **ts,
123 struct netlink_ext_ack *extack)
125 struct ila_lwt *ilwt;
126 struct ila_params *p;
127 struct nlattr *tb[ILA_ATTR_MAX + 1];
128 struct lwtunnel_state *newts;
129 const struct fib6_config *cfg6 = cfg;
130 struct ila_addr *iaddr;
131 u8 ident_type = ILA_ATYPE_USE_FORMAT;
132 u8 csum_mode = ILA_CSUM_NO_ACTION;
136 if (family != AF_INET6)
139 ret = nla_parse_nested(tb, ILA_ATTR_MAX, nla, ila_nl_policy, extack);
143 if (!tb[ILA_ATTR_LOCATOR])
146 iaddr = (struct ila_addr *)&cfg6->fc_dst;
148 if (tb[ILA_ATTR_IDENT_TYPE])
149 ident_type = nla_get_u8(tb[ILA_ATTR_IDENT_TYPE]);
151 if (ident_type == ILA_ATYPE_USE_FORMAT) {
152 /* Infer identifier type from type field in formatted
156 if (cfg6->fc_dst_len < 8 * sizeof(struct ila_locator) + 3) {
157 /* Need to have full locator and at least type field
158 * included in destination
163 eff_ident_type = iaddr->ident.type;
165 eff_ident_type = ident_type;
168 switch (eff_ident_type) {
170 /* Don't allow ILA for IID type */
174 case ILA_ATYPE_VIRT_V4:
175 case ILA_ATYPE_VIRT_UNI_V6:
176 case ILA_ATYPE_VIRT_MULTI_V6:
177 case ILA_ATYPE_NONLOCAL_ADDR:
178 /* These ILA formats are not supported yet. */
183 if (tb[ILA_ATTR_CSUM_MODE])
184 csum_mode = nla_get_u8(tb[ILA_ATTR_CSUM_MODE]);
186 if (csum_mode == ILA_CSUM_NEUTRAL_MAP &&
187 ila_csum_neutral_set(iaddr->ident)) {
188 /* Don't allow translation if checksum neutral bit is
189 * configured and it's set in the SIR address.
194 newts = lwtunnel_state_alloc(sizeof(*ilwt));
198 ilwt = ila_lwt_lwtunnel(newts);
199 ret = dst_cache_init(&ilwt->dst_cache, GFP_ATOMIC);
205 p = ila_params_lwtunnel(newts);
207 p->csum_mode = csum_mode;
208 p->ident_type = ident_type;
209 p->locator.v64 = (__force __be64)nla_get_u64(tb[ILA_ATTR_LOCATOR]);
211 /* Precompute checksum difference for translation since we
212 * know both the old locator and the new one.
214 p->locator_match = iaddr->loc;
216 ila_init_saved_csum(p);
218 newts->type = LWTUNNEL_ENCAP_ILA;
219 newts->flags |= LWTUNNEL_STATE_OUTPUT_REDIRECT |
220 LWTUNNEL_STATE_INPUT_REDIRECT;
222 if (cfg6->fc_dst_len == 8 * sizeof(struct in6_addr))
230 static void ila_destroy_state(struct lwtunnel_state *lwt)
232 dst_cache_destroy(&ila_lwt_lwtunnel(lwt)->dst_cache);
235 static int ila_fill_encap_info(struct sk_buff *skb,
236 struct lwtunnel_state *lwtstate)
238 struct ila_params *p = ila_params_lwtunnel(lwtstate);
240 if (nla_put_u64_64bit(skb, ILA_ATTR_LOCATOR, (__force u64)p->locator.v64,
242 goto nla_put_failure;
244 if (nla_put_u8(skb, ILA_ATTR_CSUM_MODE, (__force u8)p->csum_mode))
245 goto nla_put_failure;
247 if (nla_put_u8(skb, ILA_ATTR_IDENT_TYPE, (__force u8)p->ident_type))
248 goto nla_put_failure;
256 static int ila_encap_nlsize(struct lwtunnel_state *lwtstate)
258 return nla_total_size_64bit(sizeof(u64)) + /* ILA_ATTR_LOCATOR */
259 nla_total_size(sizeof(u8)) + /* ILA_ATTR_CSUM_MODE */
260 nla_total_size(sizeof(u8)) + /* ILA_ATTR_IDENT_TYPE */
264 static int ila_encap_cmp(struct lwtunnel_state *a, struct lwtunnel_state *b)
266 struct ila_params *a_p = ila_params_lwtunnel(a);
267 struct ila_params *b_p = ila_params_lwtunnel(b);
269 return (a_p->locator.v64 != b_p->locator.v64);
272 static const struct lwtunnel_encap_ops ila_encap_ops = {
273 .build_state = ila_build_state,
274 .destroy_state = ila_destroy_state,
275 .output = ila_output,
277 .fill_encap = ila_fill_encap_info,
278 .get_encap_size = ila_encap_nlsize,
279 .cmp_encap = ila_encap_cmp,
280 .owner = THIS_MODULE,
283 int ila_lwt_init(void)
285 return lwtunnel_encap_add_ops(&ila_encap_ops, LWTUNNEL_ENCAP_ILA);
288 void ila_lwt_fini(void)
290 lwtunnel_encap_del_ops(&ila_encap_ops, LWTUNNEL_ENCAP_ILA);