1 /* xfrm4_protocol.c - Generic xfrm protocol multiplexer.
3 * Copyright (C) 2013 secunet Security Networks AG
6 * Steffen Klassert <steffen.klassert@secunet.com>
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License
13 * as published by the Free Software Foundation; either version
14 * 2 of the License, or (at your option) any later version.
17 #include <linux/init.h>
18 #include <linux/mutex.h>
19 #include <linux/skbuff.h>
22 #include <net/protocol.h>
25 static struct xfrm4_protocol __rcu
*esp4_handlers __read_mostly
;
26 static struct xfrm4_protocol __rcu
*ah4_handlers __read_mostly
;
27 static struct xfrm4_protocol __rcu
*ipcomp4_handlers __read_mostly
;
28 static DEFINE_MUTEX(xfrm4_protocol_mutex
);
30 static inline struct xfrm4_protocol __rcu
**proto_handlers(u8 protocol
)
34 return &esp4_handlers
;
38 return &ipcomp4_handlers
;
44 #define for_each_protocol_rcu(head, handler) \
45 for (handler = rcu_dereference(head); \
47 handler = rcu_dereference(handler->next)) \
49 int xfrm4_rcv_cb(struct sk_buff *skb, u8 protocol, int err)
52 struct xfrm4_protocol
*handler
;
54 for_each_protocol_rcu(*proto_handlers(protocol
), handler
)
55 if ((ret
= handler
->cb_handler(skb
, err
)) <= 0)
60 EXPORT_SYMBOL(xfrm4_rcv_cb
);
62 int xfrm4_rcv_encap(struct sk_buff
*skb
, int nexthdr
, __be32 spi
,
66 struct xfrm4_protocol
*handler
;
68 XFRM_TUNNEL_SKB_CB(skb
)->tunnel
.ip4
= NULL
;
69 XFRM_SPI_SKB_CB(skb
)->family
= AF_INET
;
70 XFRM_SPI_SKB_CB(skb
)->daddroff
= offsetof(struct iphdr
, daddr
);
72 for_each_protocol_rcu(*proto_handlers(nexthdr
), handler
)
73 if ((ret
= handler
->input_handler(skb
, nexthdr
, spi
, encap_type
)) != -EINVAL
)
76 icmp_send(skb
, ICMP_DEST_UNREACH
, ICMP_PORT_UNREACH
, 0);
81 EXPORT_SYMBOL(xfrm4_rcv_encap
);
83 static int xfrm4_esp_rcv(struct sk_buff
*skb
)
86 struct xfrm4_protocol
*handler
;
88 XFRM_TUNNEL_SKB_CB(skb
)->tunnel
.ip4
= NULL
;
90 for_each_protocol_rcu(esp4_handlers
, handler
)
91 if ((ret
= handler
->handler(skb
)) != -EINVAL
)
94 icmp_send(skb
, ICMP_DEST_UNREACH
, ICMP_PORT_UNREACH
, 0);
100 static void xfrm4_esp_err(struct sk_buff
*skb
, u32 info
)
102 struct xfrm4_protocol
*handler
;
104 for_each_protocol_rcu(esp4_handlers
, handler
)
105 if (!handler
->err_handler(skb
, info
))
109 static int xfrm4_ah_rcv(struct sk_buff
*skb
)
112 struct xfrm4_protocol
*handler
;
114 XFRM_TUNNEL_SKB_CB(skb
)->tunnel
.ip4
= NULL
;
116 for_each_protocol_rcu(ah4_handlers
, handler
)
117 if ((ret
= handler
->handler(skb
)) != -EINVAL
)
120 icmp_send(skb
, ICMP_DEST_UNREACH
, ICMP_PORT_UNREACH
, 0);
126 static void xfrm4_ah_err(struct sk_buff
*skb
, u32 info
)
128 struct xfrm4_protocol
*handler
;
130 for_each_protocol_rcu(ah4_handlers
, handler
)
131 if (!handler
->err_handler(skb
, info
))
135 static int xfrm4_ipcomp_rcv(struct sk_buff
*skb
)
138 struct xfrm4_protocol
*handler
;
140 XFRM_TUNNEL_SKB_CB(skb
)->tunnel
.ip4
= NULL
;
142 for_each_protocol_rcu(ipcomp4_handlers
, handler
)
143 if ((ret
= handler
->handler(skb
)) != -EINVAL
)
146 icmp_send(skb
, ICMP_DEST_UNREACH
, ICMP_PORT_UNREACH
, 0);
152 static void xfrm4_ipcomp_err(struct sk_buff
*skb
, u32 info
)
154 struct xfrm4_protocol
*handler
;
156 for_each_protocol_rcu(ipcomp4_handlers
, handler
)
157 if (!handler
->err_handler(skb
, info
))
161 static const struct net_protocol esp4_protocol
= {
162 .handler
= xfrm4_esp_rcv
,
163 .err_handler
= xfrm4_esp_err
,
168 static const struct net_protocol ah4_protocol
= {
169 .handler
= xfrm4_ah_rcv
,
170 .err_handler
= xfrm4_ah_err
,
175 static const struct net_protocol ipcomp4_protocol
= {
176 .handler
= xfrm4_ipcomp_rcv
,
177 .err_handler
= xfrm4_ipcomp_err
,
182 static struct xfrm_input_afinfo xfrm4_input_afinfo
= {
184 .owner
= THIS_MODULE
,
185 .callback
= xfrm4_rcv_cb
,
188 static inline const struct net_protocol
*netproto(unsigned char protocol
)
192 return &esp4_protocol
;
194 return &ah4_protocol
;
196 return &ipcomp4_protocol
;
202 int xfrm4_protocol_register(struct xfrm4_protocol
*handler
,
203 unsigned char protocol
)
205 struct xfrm4_protocol __rcu
**pprev
;
206 struct xfrm4_protocol
*t
;
207 bool add_netproto
= false;
209 int priority
= handler
->priority
;
211 mutex_lock(&xfrm4_protocol_mutex
);
213 if (!rcu_dereference_protected(*proto_handlers(protocol
),
214 lockdep_is_held(&xfrm4_protocol_mutex
)))
217 for (pprev
= proto_handlers(protocol
);
218 (t
= rcu_dereference_protected(*pprev
,
219 lockdep_is_held(&xfrm4_protocol_mutex
))) != NULL
;
221 if (t
->priority
< priority
)
223 if (t
->priority
== priority
)
227 handler
->next
= *pprev
;
228 rcu_assign_pointer(*pprev
, handler
);
233 mutex_unlock(&xfrm4_protocol_mutex
);
236 if (inet_add_protocol(netproto(protocol
), protocol
)) {
237 pr_err("%s: can't add protocol\n", __func__
);
244 EXPORT_SYMBOL(xfrm4_protocol_register
);
246 int xfrm4_protocol_deregister(struct xfrm4_protocol
*handler
,
247 unsigned char protocol
)
249 struct xfrm4_protocol __rcu
**pprev
;
250 struct xfrm4_protocol
*t
;
253 mutex_lock(&xfrm4_protocol_mutex
);
255 for (pprev
= proto_handlers(protocol
);
256 (t
= rcu_dereference_protected(*pprev
,
257 lockdep_is_held(&xfrm4_protocol_mutex
))) != NULL
;
260 *pprev
= handler
->next
;
266 if (!rcu_dereference_protected(*proto_handlers(protocol
),
267 lockdep_is_held(&xfrm4_protocol_mutex
))) {
268 if (inet_del_protocol(netproto(protocol
), protocol
) < 0) {
269 pr_err("%s: can't remove protocol\n", __func__
);
274 mutex_unlock(&xfrm4_protocol_mutex
);
280 EXPORT_SYMBOL(xfrm4_protocol_deregister
);
282 void __init
xfrm4_protocol_init(void)
284 xfrm_input_register_afinfo(&xfrm4_input_afinfo
);
286 EXPORT_SYMBOL(xfrm4_protocol_init
);