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 */
36 struct mptcp_out_options {
37 #if IS_ENABLED(CONFIG_MPTCP)
43 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
44 struct in6_addr addr6;
56 struct mptcp_ext ext_copy;
61 extern struct request_sock_ops mptcp_subflow_request_sock_ops;
63 void mptcp_init(void);
65 static inline bool sk_is_mptcp(const struct sock *sk)
67 return tcp_sk(sk)->is_mptcp;
70 static inline bool rsk_is_mptcp(const struct request_sock *req)
72 return tcp_rsk(req)->is_mptcp;
75 static inline bool rsk_drop_req(const struct request_sock *req)
77 return tcp_rsk(req)->is_mptcp && tcp_rsk(req)->drop_req;
80 void mptcp_space(const struct sock *ssk, int *space, int *full_space);
81 bool mptcp_syn_options(struct sock *sk, const struct sk_buff *skb,
82 unsigned int *size, struct mptcp_out_options *opts);
83 bool mptcp_synack_options(const struct request_sock *req, unsigned int *size,
84 struct mptcp_out_options *opts);
85 bool mptcp_established_options(struct sock *sk, struct sk_buff *skb,
86 unsigned int *size, unsigned int remaining,
87 struct mptcp_out_options *opts);
88 void mptcp_incoming_options(struct sock *sk, struct sk_buff *skb);
90 void mptcp_write_options(__be32 *ptr, struct mptcp_out_options *opts);
92 /* move the skb extension owership, with the assumption that 'to' is
95 static inline void mptcp_skb_ext_move(struct sk_buff *to,
98 if (!skb_ext_exist(from, SKB_EXT_MPTCP))
101 if (WARN_ON_ONCE(to->active_extensions))
104 to->active_extensions = from->active_extensions;
105 to->extensions = from->extensions;
106 from->active_extensions = 0;
109 static inline bool mptcp_ext_matches(const struct mptcp_ext *to_ext,
110 const struct mptcp_ext *from_ext)
112 /* MPTCP always clears the ext when adding it to the skb, so
113 * holes do not bother us here
116 (to_ext && from_ext &&
117 !memcmp(from_ext, to_ext, sizeof(struct mptcp_ext)));
120 /* check if skbs can be collapsed.
121 * MPTCP collapse is allowed if neither @to or @from carry an mptcp data
122 * mapping, or if the extension of @to is the same as @from.
123 * Collapsing is not possible if @to lacks an extension, but @from carries one.
125 static inline bool mptcp_skb_can_collapse(const struct sk_buff *to,
126 const struct sk_buff *from)
128 return mptcp_ext_matches(skb_ext_find(to, SKB_EXT_MPTCP),
129 skb_ext_find(from, SKB_EXT_MPTCP));
132 void mptcp_seq_show(struct seq_file *seq);
133 int mptcp_subflow_init_cookie_req(struct request_sock *req,
134 const struct sock *sk_listener,
135 struct sk_buff *skb);
138 static inline void mptcp_init(void)
142 static inline bool sk_is_mptcp(const struct sock *sk)
147 static inline bool rsk_is_mptcp(const struct request_sock *req)
152 static inline bool rsk_drop_req(const struct request_sock *req)
157 static inline void mptcp_parse_option(const struct sk_buff *skb,
158 const unsigned char *ptr, int opsize,
159 struct tcp_options_received *opt_rx)
163 static inline bool mptcp_syn_options(struct sock *sk, const struct sk_buff *skb,
165 struct mptcp_out_options *opts)
170 static inline bool mptcp_synack_options(const struct request_sock *req,
172 struct mptcp_out_options *opts)
177 static inline bool mptcp_established_options(struct sock *sk,
180 unsigned int remaining,
181 struct mptcp_out_options *opts)
186 static inline void mptcp_incoming_options(struct sock *sk,
191 static inline void mptcp_skb_ext_move(struct sk_buff *to,
192 const struct sk_buff *from)
196 static inline bool mptcp_skb_can_collapse(const struct sk_buff *to,
197 const struct sk_buff *from)
202 static inline void mptcp_space(const struct sock *ssk, int *s, int *fs) { }
203 static inline void mptcp_seq_show(struct seq_file *seq) { }
205 static inline int mptcp_subflow_init_cookie_req(struct request_sock *req,
206 const struct sock *sk_listener,
209 return 0; /* TCP fallback */
211 #endif /* CONFIG_MPTCP */
213 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
214 int mptcpv6_init(void);
215 void mptcpv6_handle_mapped(struct sock *sk, bool mapped);
216 #elif IS_ENABLED(CONFIG_IPV6)
217 static inline int mptcpv6_init(void) { return 0; }
218 static inline void mptcpv6_handle_mapped(struct sock *sk, bool mapped) { }
221 #endif /* __NET_MPTCP_H */