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 */
37 struct mptcp_out_options {
38 #if IS_ENABLED(CONFIG_MPTCP)
44 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
45 struct in6_addr addr6;
58 struct mptcp_ext ext_copy;
63 extern struct request_sock_ops mptcp_subflow_request_sock_ops;
65 void mptcp_init(void);
67 static inline bool sk_is_mptcp(const struct sock *sk)
69 return tcp_sk(sk)->is_mptcp;
72 static inline bool rsk_is_mptcp(const struct request_sock *req)
74 return tcp_rsk(req)->is_mptcp;
77 static inline bool rsk_drop_req(const struct request_sock *req)
79 return tcp_rsk(req)->is_mptcp && tcp_rsk(req)->drop_req;
82 void mptcp_space(const struct sock *ssk, int *space, int *full_space);
83 bool mptcp_syn_options(struct sock *sk, const struct sk_buff *skb,
84 unsigned int *size, struct mptcp_out_options *opts);
85 bool mptcp_synack_options(const struct request_sock *req, unsigned int *size,
86 struct mptcp_out_options *opts);
87 bool mptcp_established_options(struct sock *sk, struct sk_buff *skb,
88 unsigned int *size, unsigned int remaining,
89 struct mptcp_out_options *opts);
90 void mptcp_incoming_options(struct sock *sk, struct sk_buff *skb);
92 void mptcp_write_options(__be32 *ptr, const struct tcp_sock *tp,
93 struct mptcp_out_options *opts);
95 /* move the skb extension owership, with the assumption that 'to' is
98 static inline void mptcp_skb_ext_move(struct sk_buff *to,
101 if (!skb_ext_exist(from, SKB_EXT_MPTCP))
104 if (WARN_ON_ONCE(to->active_extensions))
107 to->active_extensions = from->active_extensions;
108 to->extensions = from->extensions;
109 from->active_extensions = 0;
112 static inline void mptcp_skb_ext_copy(struct sk_buff *to,
113 struct sk_buff *from)
115 struct mptcp_ext *from_ext;
117 from_ext = skb_ext_find(from, SKB_EXT_MPTCP);
121 from_ext->frozen = 1;
122 skb_ext_copy(to, from);
125 static inline bool mptcp_ext_matches(const struct mptcp_ext *to_ext,
126 const struct mptcp_ext *from_ext)
128 /* MPTCP always clears the ext when adding it to the skb, so
129 * holes do not bother us here
132 (to_ext && from_ext &&
133 !memcmp(from_ext, to_ext, sizeof(struct mptcp_ext)));
136 /* check if skbs can be collapsed.
137 * MPTCP collapse is allowed if neither @to or @from carry an mptcp data
138 * mapping, or if the extension of @to is the same as @from.
139 * Collapsing is not possible if @to lacks an extension, but @from carries one.
141 static inline bool mptcp_skb_can_collapse(const struct sk_buff *to,
142 const struct sk_buff *from)
144 return mptcp_ext_matches(skb_ext_find(to, SKB_EXT_MPTCP),
145 skb_ext_find(from, SKB_EXT_MPTCP));
148 void mptcp_seq_show(struct seq_file *seq);
149 int mptcp_subflow_init_cookie_req(struct request_sock *req,
150 const struct sock *sk_listener,
151 struct sk_buff *skb);
154 static inline void mptcp_init(void)
158 static inline bool sk_is_mptcp(const struct sock *sk)
163 static inline bool rsk_is_mptcp(const struct request_sock *req)
168 static inline bool rsk_drop_req(const struct request_sock *req)
173 static inline void mptcp_parse_option(const struct sk_buff *skb,
174 const unsigned char *ptr, int opsize,
175 struct tcp_options_received *opt_rx)
179 static inline bool mptcp_syn_options(struct sock *sk, const struct sk_buff *skb,
181 struct mptcp_out_options *opts)
186 static inline bool mptcp_synack_options(const struct request_sock *req,
188 struct mptcp_out_options *opts)
193 static inline bool mptcp_established_options(struct sock *sk,
196 unsigned int remaining,
197 struct mptcp_out_options *opts)
202 static inline void mptcp_incoming_options(struct sock *sk,
207 static inline void mptcp_skb_ext_move(struct sk_buff *to,
208 const struct sk_buff *from)
212 static inline void mptcp_skb_ext_copy(struct sk_buff *to,
213 struct sk_buff *from)
217 static inline bool mptcp_skb_can_collapse(const struct sk_buff *to,
218 const struct sk_buff *from)
223 static inline void mptcp_space(const struct sock *ssk, int *s, int *fs) { }
224 static inline void mptcp_seq_show(struct seq_file *seq) { }
226 static inline int mptcp_subflow_init_cookie_req(struct request_sock *req,
227 const struct sock *sk_listener,
230 return 0; /* TCP fallback */
232 #endif /* CONFIG_MPTCP */
234 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
235 int mptcpv6_init(void);
236 void mptcpv6_handle_mapped(struct sock *sk, bool mapped);
237 #elif IS_ENABLED(CONFIG_IPV6)
238 static inline int mptcpv6_init(void) { return 0; }
239 static inline void mptcpv6_handle_mapped(struct sock *sk, bool mapped) { }
242 #endif /* __NET_MPTCP_H */