1 /* SPDX-License-Identifier: GPL-2.0 */
5 * Copyright (c) 2017 - 2019, Intel Corporation.
11 #include <linux/skbuff.h>
12 #include <linux/tcp.h>
13 #include <linux/types.h>
17 /* MPTCP sk_buff extension data */
39 #define MPTCP_RM_IDS_MAX 8
41 struct mptcp_rm_list {
42 u8 ids[MPTCP_RM_IDS_MAX];
46 struct mptcp_addr_info {
52 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
53 struct in6_addr addr6;
58 struct mptcp_out_options {
59 #if IS_ENABLED(CONFIG_MPTCP)
61 struct mptcp_rm_list rm_list;
78 struct mptcp_addr_info addr;
82 struct mptcp_ext ext_copy;
96 void mptcp_init(void);
98 static inline bool sk_is_mptcp(const struct sock *sk)
100 return tcp_sk(sk)->is_mptcp;
103 static inline bool rsk_is_mptcp(const struct request_sock *req)
105 return tcp_rsk(req)->is_mptcp;
108 static inline bool rsk_drop_req(const struct request_sock *req)
110 return tcp_rsk(req)->is_mptcp && tcp_rsk(req)->drop_req;
113 void mptcp_space(const struct sock *ssk, int *space, int *full_space);
114 bool mptcp_syn_options(struct sock *sk, const struct sk_buff *skb,
115 unsigned int *size, struct mptcp_out_options *opts);
116 bool mptcp_synack_options(const struct request_sock *req, unsigned int *size,
117 struct mptcp_out_options *opts);
118 bool mptcp_established_options(struct sock *sk, struct sk_buff *skb,
119 unsigned int *size, unsigned int remaining,
120 struct mptcp_out_options *opts);
121 bool mptcp_incoming_options(struct sock *sk, struct sk_buff *skb);
123 void mptcp_write_options(__be32 *ptr, const struct tcp_sock *tp,
124 struct mptcp_out_options *opts);
126 /* move the skb extension owership, with the assumption that 'to' is
129 static inline void mptcp_skb_ext_move(struct sk_buff *to,
130 struct sk_buff *from)
132 if (!skb_ext_exist(from, SKB_EXT_MPTCP))
135 if (WARN_ON_ONCE(to->active_extensions))
138 to->active_extensions = from->active_extensions;
139 to->extensions = from->extensions;
140 from->active_extensions = 0;
143 static inline void mptcp_skb_ext_copy(struct sk_buff *to,
144 struct sk_buff *from)
146 struct mptcp_ext *from_ext;
148 from_ext = skb_ext_find(from, SKB_EXT_MPTCP);
152 from_ext->frozen = 1;
153 skb_ext_copy(to, from);
156 static inline bool mptcp_ext_matches(const struct mptcp_ext *to_ext,
157 const struct mptcp_ext *from_ext)
159 /* MPTCP always clears the ext when adding it to the skb, so
160 * holes do not bother us here
163 (to_ext && from_ext &&
164 !memcmp(from_ext, to_ext, sizeof(struct mptcp_ext)));
167 /* check if skbs can be collapsed.
168 * MPTCP collapse is allowed if neither @to or @from carry an mptcp data
169 * mapping, or if the extension of @to is the same as @from.
170 * Collapsing is not possible if @to lacks an extension, but @from carries one.
172 static inline bool mptcp_skb_can_collapse(const struct sk_buff *to,
173 const struct sk_buff *from)
175 return mptcp_ext_matches(skb_ext_find(to, SKB_EXT_MPTCP),
176 skb_ext_find(from, SKB_EXT_MPTCP));
179 void mptcp_seq_show(struct seq_file *seq);
180 int mptcp_subflow_init_cookie_req(struct request_sock *req,
181 const struct sock *sk_listener,
182 struct sk_buff *skb);
183 struct request_sock *mptcp_subflow_reqsk_alloc(const struct request_sock_ops *ops,
184 struct sock *sk_listener,
185 bool attach_listener);
187 __be32 mptcp_get_reset_option(const struct sk_buff *skb);
189 static inline __be32 mptcp_reset_option(const struct sk_buff *skb)
191 if (skb_ext_exist(skb, SKB_EXT_MPTCP))
192 return mptcp_get_reset_option(skb);
198 static inline void mptcp_init(void)
202 static inline bool sk_is_mptcp(const struct sock *sk)
207 static inline bool rsk_is_mptcp(const struct request_sock *req)
212 static inline bool rsk_drop_req(const struct request_sock *req)
217 static inline void mptcp_parse_option(const struct sk_buff *skb,
218 const unsigned char *ptr, int opsize,
219 struct tcp_options_received *opt_rx)
223 static inline bool mptcp_syn_options(struct sock *sk, const struct sk_buff *skb,
225 struct mptcp_out_options *opts)
230 static inline bool mptcp_synack_options(const struct request_sock *req,
232 struct mptcp_out_options *opts)
237 static inline bool mptcp_established_options(struct sock *sk,
240 unsigned int remaining,
241 struct mptcp_out_options *opts)
246 static inline bool mptcp_incoming_options(struct sock *sk,
252 static inline void mptcp_skb_ext_move(struct sk_buff *to,
253 const struct sk_buff *from)
257 static inline void mptcp_skb_ext_copy(struct sk_buff *to,
258 struct sk_buff *from)
262 static inline bool mptcp_skb_can_collapse(const struct sk_buff *to,
263 const struct sk_buff *from)
268 static inline void mptcp_space(const struct sock *ssk, int *s, int *fs) { }
269 static inline void mptcp_seq_show(struct seq_file *seq) { }
271 static inline int mptcp_subflow_init_cookie_req(struct request_sock *req,
272 const struct sock *sk_listener,
275 return 0; /* TCP fallback */
278 static inline struct request_sock *mptcp_subflow_reqsk_alloc(const struct request_sock_ops *ops,
279 struct sock *sk_listener,
280 bool attach_listener)
285 static inline __be32 mptcp_reset_option(const struct sk_buff *skb) { return htonl(0u); }
286 #endif /* CONFIG_MPTCP */
288 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
289 int mptcpv6_init(void);
290 void mptcpv6_handle_mapped(struct sock *sk, bool mapped);
291 #elif IS_ENABLED(CONFIG_IPV6)
292 static inline int mptcpv6_init(void) { return 0; }
293 static inline void mptcpv6_handle_mapped(struct sock *sk, bool mapped) { }
296 #endif /* __NET_MPTCP_H */