xref: /linux/drivers/net/ethernet/mellanox/mlxsw/spectrum_ipip.c (revision ec8a42e7343234802b9054874fe01810880289ce)
1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /* Copyright (c) 2017-2018 Mellanox Technologies. All rights reserved */
3 
4 #include <net/ip_tunnels.h>
5 #include <net/ip6_tunnel.h>
6 #include <net/inet_ecn.h>
7 
8 #include "spectrum_ipip.h"
9 #include "reg.h"
10 
11 struct ip_tunnel_parm
12 mlxsw_sp_ipip_netdev_parms4(const struct net_device *ol_dev)
13 {
14 	struct ip_tunnel *tun = netdev_priv(ol_dev);
15 
16 	return tun->parms;
17 }
18 
19 struct __ip6_tnl_parm
20 mlxsw_sp_ipip_netdev_parms6(const struct net_device *ol_dev)
21 {
22 	struct ip6_tnl *tun = netdev_priv(ol_dev);
23 
24 	return tun->parms;
25 }
26 
27 static bool mlxsw_sp_ipip_parms4_has_ikey(struct ip_tunnel_parm parms)
28 {
29 	return !!(parms.i_flags & TUNNEL_KEY);
30 }
31 
32 static bool mlxsw_sp_ipip_parms4_has_okey(struct ip_tunnel_parm parms)
33 {
34 	return !!(parms.o_flags & TUNNEL_KEY);
35 }
36 
37 static u32 mlxsw_sp_ipip_parms4_ikey(struct ip_tunnel_parm parms)
38 {
39 	return mlxsw_sp_ipip_parms4_has_ikey(parms) ?
40 		be32_to_cpu(parms.i_key) : 0;
41 }
42 
43 static u32 mlxsw_sp_ipip_parms4_okey(struct ip_tunnel_parm parms)
44 {
45 	return mlxsw_sp_ipip_parms4_has_okey(parms) ?
46 		be32_to_cpu(parms.o_key) : 0;
47 }
48 
49 static union mlxsw_sp_l3addr
50 mlxsw_sp_ipip_parms4_saddr(struct ip_tunnel_parm parms)
51 {
52 	return (union mlxsw_sp_l3addr) { .addr4 = parms.iph.saddr };
53 }
54 
55 static union mlxsw_sp_l3addr
56 mlxsw_sp_ipip_parms6_saddr(struct __ip6_tnl_parm parms)
57 {
58 	return (union mlxsw_sp_l3addr) { .addr6 = parms.laddr };
59 }
60 
61 static union mlxsw_sp_l3addr
62 mlxsw_sp_ipip_parms4_daddr(struct ip_tunnel_parm parms)
63 {
64 	return (union mlxsw_sp_l3addr) { .addr4 = parms.iph.daddr };
65 }
66 
67 static union mlxsw_sp_l3addr
68 mlxsw_sp_ipip_parms6_daddr(struct __ip6_tnl_parm parms)
69 {
70 	return (union mlxsw_sp_l3addr) { .addr6 = parms.raddr };
71 }
72 
73 union mlxsw_sp_l3addr
74 mlxsw_sp_ipip_netdev_saddr(enum mlxsw_sp_l3proto proto,
75 			   const struct net_device *ol_dev)
76 {
77 	struct ip_tunnel_parm parms4;
78 	struct __ip6_tnl_parm parms6;
79 
80 	switch (proto) {
81 	case MLXSW_SP_L3_PROTO_IPV4:
82 		parms4 = mlxsw_sp_ipip_netdev_parms4(ol_dev);
83 		return mlxsw_sp_ipip_parms4_saddr(parms4);
84 	case MLXSW_SP_L3_PROTO_IPV6:
85 		parms6 = mlxsw_sp_ipip_netdev_parms6(ol_dev);
86 		return mlxsw_sp_ipip_parms6_saddr(parms6);
87 	}
88 
89 	WARN_ON(1);
90 	return (union mlxsw_sp_l3addr) {0};
91 }
92 
93 static __be32 mlxsw_sp_ipip_netdev_daddr4(const struct net_device *ol_dev)
94 {
95 
96 	struct ip_tunnel_parm parms4 = mlxsw_sp_ipip_netdev_parms4(ol_dev);
97 
98 	return mlxsw_sp_ipip_parms4_daddr(parms4).addr4;
99 }
100 
101 static union mlxsw_sp_l3addr
102 mlxsw_sp_ipip_netdev_daddr(enum mlxsw_sp_l3proto proto,
103 			   const struct net_device *ol_dev)
104 {
105 	struct ip_tunnel_parm parms4;
106 	struct __ip6_tnl_parm parms6;
107 
108 	switch (proto) {
109 	case MLXSW_SP_L3_PROTO_IPV4:
110 		parms4 = mlxsw_sp_ipip_netdev_parms4(ol_dev);
111 		return mlxsw_sp_ipip_parms4_daddr(parms4);
112 	case MLXSW_SP_L3_PROTO_IPV6:
113 		parms6 = mlxsw_sp_ipip_netdev_parms6(ol_dev);
114 		return mlxsw_sp_ipip_parms6_daddr(parms6);
115 	}
116 
117 	WARN_ON(1);
118 	return (union mlxsw_sp_l3addr) {0};
119 }
120 
121 bool mlxsw_sp_l3addr_is_zero(union mlxsw_sp_l3addr addr)
122 {
123 	union mlxsw_sp_l3addr naddr = {0};
124 
125 	return !memcmp(&addr, &naddr, sizeof(naddr));
126 }
127 
128 static int
129 mlxsw_sp_ipip_nexthop_update_gre4(struct mlxsw_sp *mlxsw_sp, u32 adj_index,
130 				  struct mlxsw_sp_ipip_entry *ipip_entry)
131 {
132 	u16 rif_index = mlxsw_sp_ipip_lb_rif_index(ipip_entry->ol_lb);
133 	__be32 daddr4 = mlxsw_sp_ipip_netdev_daddr4(ipip_entry->ol_dev);
134 	char ratr_pl[MLXSW_REG_RATR_LEN];
135 
136 	mlxsw_reg_ratr_pack(ratr_pl, MLXSW_REG_RATR_OP_WRITE_WRITE_ENTRY,
137 			    true, MLXSW_REG_RATR_TYPE_IPIP,
138 			    adj_index, rif_index);
139 	mlxsw_reg_ratr_ipip4_entry_pack(ratr_pl, be32_to_cpu(daddr4));
140 
141 	return mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(ratr), ratr_pl);
142 }
143 
144 static int
145 mlxsw_sp_ipip_decap_config_gre4(struct mlxsw_sp *mlxsw_sp,
146 				struct mlxsw_sp_ipip_entry *ipip_entry,
147 				u32 tunnel_index)
148 {
149 	u16 rif_index = mlxsw_sp_ipip_lb_rif_index(ipip_entry->ol_lb);
150 	u16 ul_rif_id = mlxsw_sp_ipip_lb_ul_rif_id(ipip_entry->ol_lb);
151 	char rtdp_pl[MLXSW_REG_RTDP_LEN];
152 	struct ip_tunnel_parm parms;
153 	unsigned int type_check;
154 	bool has_ikey;
155 	u32 daddr4;
156 	u32 ikey;
157 
158 	parms = mlxsw_sp_ipip_netdev_parms4(ipip_entry->ol_dev);
159 	has_ikey = mlxsw_sp_ipip_parms4_has_ikey(parms);
160 	ikey = mlxsw_sp_ipip_parms4_ikey(parms);
161 
162 	mlxsw_reg_rtdp_pack(rtdp_pl, MLXSW_REG_RTDP_TYPE_IPIP, tunnel_index);
163 	mlxsw_reg_rtdp_egress_router_interface_set(rtdp_pl, ul_rif_id);
164 
165 	type_check = has_ikey ?
166 		MLXSW_REG_RTDP_IPIP_TYPE_CHECK_ALLOW_GRE_KEY :
167 		MLXSW_REG_RTDP_IPIP_TYPE_CHECK_ALLOW_GRE;
168 
169 	/* Linux demuxes tunnels based on packet SIP (which must match tunnel
170 	 * remote IP). Thus configure decap so that it filters out packets that
171 	 * are not IPv4 or have the wrong SIP. IPIP_DECAP_ERROR trap is
172 	 * generated for packets that fail this criterion. Linux then handles
173 	 * such packets in slow path and generates ICMP destination unreachable.
174 	 */
175 	daddr4 = be32_to_cpu(mlxsw_sp_ipip_netdev_daddr4(ipip_entry->ol_dev));
176 	mlxsw_reg_rtdp_ipip4_pack(rtdp_pl, rif_index,
177 				  MLXSW_REG_RTDP_IPIP_SIP_CHECK_FILTER_IPV4,
178 				  type_check, has_ikey, daddr4, ikey);
179 
180 	return mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(rtdp), rtdp_pl);
181 }
182 
183 static bool mlxsw_sp_ipip_tunnel_complete(enum mlxsw_sp_l3proto proto,
184 					  const struct net_device *ol_dev)
185 {
186 	union mlxsw_sp_l3addr saddr = mlxsw_sp_ipip_netdev_saddr(proto, ol_dev);
187 	union mlxsw_sp_l3addr daddr = mlxsw_sp_ipip_netdev_daddr(proto, ol_dev);
188 
189 	/* Tunnels with unset local or remote address are valid in Linux and
190 	 * used for lightweight tunnels (LWT) and Non-Broadcast Multi-Access
191 	 * (NBMA) tunnels. In principle these can be offloaded, but the driver
192 	 * currently doesn't support this. So punt.
193 	 */
194 	return !mlxsw_sp_l3addr_is_zero(saddr) &&
195 	       !mlxsw_sp_l3addr_is_zero(daddr);
196 }
197 
198 static bool mlxsw_sp_ipip_can_offload_gre4(const struct mlxsw_sp *mlxsw_sp,
199 					   const struct net_device *ol_dev)
200 {
201 	struct ip_tunnel *tunnel = netdev_priv(ol_dev);
202 	__be16 okflags = TUNNEL_KEY; /* We can't offload any other features. */
203 	bool inherit_ttl = tunnel->parms.iph.ttl == 0;
204 	bool inherit_tos = tunnel->parms.iph.tos & 0x1;
205 
206 	return (tunnel->parms.i_flags & ~okflags) == 0 &&
207 	       (tunnel->parms.o_flags & ~okflags) == 0 &&
208 	       inherit_ttl && inherit_tos &&
209 	       mlxsw_sp_ipip_tunnel_complete(MLXSW_SP_L3_PROTO_IPV4, ol_dev);
210 }
211 
212 static struct mlxsw_sp_rif_ipip_lb_config
213 mlxsw_sp_ipip_ol_loopback_config_gre4(struct mlxsw_sp *mlxsw_sp,
214 				      const struct net_device *ol_dev)
215 {
216 	struct ip_tunnel_parm parms = mlxsw_sp_ipip_netdev_parms4(ol_dev);
217 	enum mlxsw_reg_ritr_loopback_ipip_type lb_ipipt;
218 
219 	lb_ipipt = mlxsw_sp_ipip_parms4_has_okey(parms) ?
220 		MLXSW_REG_RITR_LOOPBACK_IPIP_TYPE_IP_IN_GRE_KEY_IN_IP :
221 		MLXSW_REG_RITR_LOOPBACK_IPIP_TYPE_IP_IN_GRE_IN_IP;
222 	return (struct mlxsw_sp_rif_ipip_lb_config){
223 		.lb_ipipt = lb_ipipt,
224 		.okey = mlxsw_sp_ipip_parms4_okey(parms),
225 		.ul_protocol = MLXSW_SP_L3_PROTO_IPV4,
226 		.saddr = mlxsw_sp_ipip_netdev_saddr(MLXSW_SP_L3_PROTO_IPV4,
227 						    ol_dev),
228 	};
229 }
230 
231 static int
232 mlxsw_sp_ipip_ol_netdev_change_gre4(struct mlxsw_sp *mlxsw_sp,
233 				    struct mlxsw_sp_ipip_entry *ipip_entry,
234 				    struct netlink_ext_ack *extack)
235 {
236 	union mlxsw_sp_l3addr old_saddr, new_saddr;
237 	union mlxsw_sp_l3addr old_daddr, new_daddr;
238 	struct ip_tunnel_parm new_parms;
239 	bool update_tunnel = false;
240 	bool update_decap = false;
241 	bool update_nhs = false;
242 	int err = 0;
243 
244 	new_parms = mlxsw_sp_ipip_netdev_parms4(ipip_entry->ol_dev);
245 
246 	new_saddr = mlxsw_sp_ipip_parms4_saddr(new_parms);
247 	old_saddr = mlxsw_sp_ipip_parms4_saddr(ipip_entry->parms4);
248 	new_daddr = mlxsw_sp_ipip_parms4_daddr(new_parms);
249 	old_daddr = mlxsw_sp_ipip_parms4_daddr(ipip_entry->parms4);
250 
251 	if (!mlxsw_sp_l3addr_eq(&new_saddr, &old_saddr)) {
252 		u16 ul_tb_id = mlxsw_sp_ipip_dev_ul_tb_id(ipip_entry->ol_dev);
253 
254 		/* Since the local address has changed, if there is another
255 		 * tunnel with a matching saddr, both need to be demoted.
256 		 */
257 		if (mlxsw_sp_ipip_demote_tunnel_by_saddr(mlxsw_sp,
258 							 MLXSW_SP_L3_PROTO_IPV4,
259 							 new_saddr, ul_tb_id,
260 							 ipip_entry)) {
261 			mlxsw_sp_ipip_entry_demote_tunnel(mlxsw_sp, ipip_entry);
262 			return 0;
263 		}
264 
265 		update_tunnel = true;
266 	} else if ((mlxsw_sp_ipip_parms4_okey(ipip_entry->parms4) !=
267 		    mlxsw_sp_ipip_parms4_okey(new_parms)) ||
268 		   ipip_entry->parms4.link != new_parms.link) {
269 		update_tunnel = true;
270 	} else if (!mlxsw_sp_l3addr_eq(&new_daddr, &old_daddr)) {
271 		update_nhs = true;
272 	} else if (mlxsw_sp_ipip_parms4_ikey(ipip_entry->parms4) !=
273 		   mlxsw_sp_ipip_parms4_ikey(new_parms)) {
274 		update_decap = true;
275 	}
276 
277 	if (update_tunnel)
278 		err = __mlxsw_sp_ipip_entry_update_tunnel(mlxsw_sp, ipip_entry,
279 							  true, true, true,
280 							  extack);
281 	else if (update_nhs)
282 		err = __mlxsw_sp_ipip_entry_update_tunnel(mlxsw_sp, ipip_entry,
283 							  false, false, true,
284 							  extack);
285 	else if (update_decap)
286 		err = __mlxsw_sp_ipip_entry_update_tunnel(mlxsw_sp, ipip_entry,
287 							  false, false, false,
288 							  extack);
289 
290 	ipip_entry->parms4 = new_parms;
291 	return err;
292 }
293 
294 static const struct mlxsw_sp_ipip_ops mlxsw_sp_ipip_gre4_ops = {
295 	.dev_type = ARPHRD_IPGRE,
296 	.ul_proto = MLXSW_SP_L3_PROTO_IPV4,
297 	.nexthop_update = mlxsw_sp_ipip_nexthop_update_gre4,
298 	.decap_config = mlxsw_sp_ipip_decap_config_gre4,
299 	.can_offload = mlxsw_sp_ipip_can_offload_gre4,
300 	.ol_loopback_config = mlxsw_sp_ipip_ol_loopback_config_gre4,
301 	.ol_netdev_change = mlxsw_sp_ipip_ol_netdev_change_gre4,
302 };
303 
304 const struct mlxsw_sp_ipip_ops *mlxsw_sp_ipip_ops_arr[] = {
305 	[MLXSW_SP_IPIP_TYPE_GRE4] = &mlxsw_sp_ipip_gre4_ops,
306 };
307 
308 static int mlxsw_sp_ipip_ecn_encap_init_one(struct mlxsw_sp *mlxsw_sp,
309 					    u8 inner_ecn, u8 outer_ecn)
310 {
311 	char tieem_pl[MLXSW_REG_TIEEM_LEN];
312 
313 	mlxsw_reg_tieem_pack(tieem_pl, inner_ecn, outer_ecn);
314 	return mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(tieem), tieem_pl);
315 }
316 
317 int mlxsw_sp_ipip_ecn_encap_init(struct mlxsw_sp *mlxsw_sp)
318 {
319 	int i;
320 
321 	/* Iterate over inner ECN values */
322 	for (i = INET_ECN_NOT_ECT; i <= INET_ECN_CE; i++) {
323 		u8 outer_ecn = INET_ECN_encapsulate(0, i);
324 		int err;
325 
326 		err = mlxsw_sp_ipip_ecn_encap_init_one(mlxsw_sp, i, outer_ecn);
327 		if (err)
328 			return err;
329 	}
330 
331 	return 0;
332 }
333 
334 static int mlxsw_sp_ipip_ecn_decap_init_one(struct mlxsw_sp *mlxsw_sp,
335 					    u8 inner_ecn, u8 outer_ecn)
336 {
337 	char tidem_pl[MLXSW_REG_TIDEM_LEN];
338 	bool trap_en, set_ce = false;
339 	u8 new_inner_ecn;
340 
341 	trap_en = __INET_ECN_decapsulate(outer_ecn, inner_ecn, &set_ce);
342 	new_inner_ecn = set_ce ? INET_ECN_CE : inner_ecn;
343 
344 	mlxsw_reg_tidem_pack(tidem_pl, outer_ecn, inner_ecn, new_inner_ecn,
345 			     trap_en, trap_en ? MLXSW_TRAP_ID_DECAP_ECN0 : 0);
346 	return mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(tidem), tidem_pl);
347 }
348 
349 int mlxsw_sp_ipip_ecn_decap_init(struct mlxsw_sp *mlxsw_sp)
350 {
351 	int i, j, err;
352 
353 	/* Iterate over inner ECN values */
354 	for (i = INET_ECN_NOT_ECT; i <= INET_ECN_CE; i++) {
355 		/* Iterate over outer ECN values */
356 		for (j = INET_ECN_NOT_ECT; j <= INET_ECN_CE; j++) {
357 			err = mlxsw_sp_ipip_ecn_decap_init_one(mlxsw_sp, i, j);
358 			if (err)
359 				return err;
360 		}
361 	}
362 
363 	return 0;
364 }
365