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>
19 /* MPTCP sk_buff extension data */
42 #define MPTCP_RM_IDS_MAX 8
44 struct mptcp_rm_list {
45 u8 ids[MPTCP_RM_IDS_MAX];
49 struct mptcp_addr_info {
55 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
56 struct in6_addr addr6;
61 struct mptcp_out_options {
62 #if IS_ENABLED(CONFIG_MPTCP)
64 struct mptcp_rm_list rm_list;
81 struct mptcp_addr_info addr;
85 struct mptcp_ext ext_copy;
99 extern struct request_sock_ops mptcp_subflow_request_sock_ops;
101 void mptcp_init(void);
103 static inline bool sk_is_mptcp(const struct sock *sk)
105 return tcp_sk(sk)->is_mptcp;
108 static inline bool rsk_is_mptcp(const struct request_sock *req)
110 return tcp_rsk(req)->is_mptcp;
113 static inline bool rsk_drop_req(const struct request_sock *req)
115 return tcp_rsk(req)->is_mptcp && tcp_rsk(req)->drop_req;
118 void mptcp_space(const struct sock *ssk, int *space, int *full_space);
119 bool mptcp_syn_options(struct sock *sk, const struct sk_buff *skb,
120 unsigned int *size, struct mptcp_out_options *opts);
121 bool mptcp_synack_options(const struct request_sock *req, unsigned int *size,
122 struct mptcp_out_options *opts);
123 bool mptcp_established_options(struct sock *sk, struct sk_buff *skb,
124 unsigned int *size, unsigned int remaining,
125 struct mptcp_out_options *opts);
126 bool mptcp_incoming_options(struct sock *sk, struct sk_buff *skb);
128 void mptcp_write_options(struct tcphdr *th, __be32 *ptr, struct tcp_sock *tp,
129 struct mptcp_out_options *opts);
131 void mptcp_diag_fill_info(struct mptcp_sock *msk, struct mptcp_info *info);
133 /* move the skb extension owership, with the assumption that 'to' is
136 static inline void mptcp_skb_ext_move(struct sk_buff *to,
137 struct sk_buff *from)
139 if (!skb_ext_exist(from, SKB_EXT_MPTCP))
142 if (WARN_ON_ONCE(to->active_extensions))
145 to->active_extensions = from->active_extensions;
146 to->extensions = from->extensions;
147 from->active_extensions = 0;
150 static inline void mptcp_skb_ext_copy(struct sk_buff *to,
151 struct sk_buff *from)
153 struct mptcp_ext *from_ext;
155 from_ext = skb_ext_find(from, SKB_EXT_MPTCP);
159 from_ext->frozen = 1;
160 skb_ext_copy(to, from);
163 static inline bool mptcp_ext_matches(const struct mptcp_ext *to_ext,
164 const struct mptcp_ext *from_ext)
166 /* MPTCP always clears the ext when adding it to the skb, so
167 * holes do not bother us here
170 (to_ext && from_ext &&
171 !memcmp(from_ext, to_ext, sizeof(struct mptcp_ext)));
174 /* check if skbs can be collapsed.
175 * MPTCP collapse is allowed if neither @to or @from carry an mptcp data
176 * mapping, or if the extension of @to is the same as @from.
177 * Collapsing is not possible if @to lacks an extension, but @from carries one.
179 static inline bool mptcp_skb_can_collapse(const struct sk_buff *to,
180 const struct sk_buff *from)
182 return mptcp_ext_matches(skb_ext_find(to, SKB_EXT_MPTCP),
183 skb_ext_find(from, SKB_EXT_MPTCP));
186 void mptcp_seq_show(struct seq_file *seq);
187 int mptcp_subflow_init_cookie_req(struct request_sock *req,
188 const struct sock *sk_listener,
189 struct sk_buff *skb);
191 __be32 mptcp_get_reset_option(const struct sk_buff *skb);
193 static inline __be32 mptcp_reset_option(const struct sk_buff *skb)
195 if (skb_ext_exist(skb, SKB_EXT_MPTCP))
196 return mptcp_get_reset_option(skb);
202 static inline void mptcp_init(void)
206 static inline bool sk_is_mptcp(const struct sock *sk)
211 static inline bool rsk_is_mptcp(const struct request_sock *req)
216 static inline bool rsk_drop_req(const struct request_sock *req)
221 static inline bool mptcp_syn_options(struct sock *sk, const struct sk_buff *skb,
223 struct mptcp_out_options *opts)
228 static inline bool mptcp_synack_options(const struct request_sock *req,
230 struct mptcp_out_options *opts)
235 static inline bool mptcp_established_options(struct sock *sk,
238 unsigned int remaining,
239 struct mptcp_out_options *opts)
244 static inline bool mptcp_incoming_options(struct sock *sk,
250 static inline void mptcp_skb_ext_move(struct sk_buff *to,
251 const struct sk_buff *from)
255 static inline void mptcp_skb_ext_copy(struct sk_buff *to,
256 struct sk_buff *from)
260 static inline bool mptcp_skb_can_collapse(const struct sk_buff *to,
261 const struct sk_buff *from)
266 static inline void mptcp_space(const struct sock *ssk, int *s, int *fs) { }
267 static inline void mptcp_seq_show(struct seq_file *seq) { }
269 static inline int mptcp_subflow_init_cookie_req(struct request_sock *req,
270 const struct sock *sk_listener,
273 return 0; /* TCP fallback */
276 static inline __be32 mptcp_reset_option(const struct sk_buff *skb) { return htonl(0u); }
277 #endif /* CONFIG_MPTCP */
279 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
280 int mptcpv6_init(void);
281 void mptcpv6_handle_mapped(struct sock *sk, bool mapped);
282 #elif IS_ENABLED(CONFIG_IPV6)
283 static inline int mptcpv6_init(void) { return 0; }
284 static inline void mptcpv6_handle_mapped(struct sock *sk, bool mapped) { }
287 #if defined(CONFIG_MPTCP) && defined(CONFIG_BPF_SYSCALL)
288 struct mptcp_sock *bpf_mptcp_sock_from_subflow(struct sock *sk);
290 static inline struct mptcp_sock *bpf_mptcp_sock_from_subflow(struct sock *sk) { return NULL; }
293 #endif /* __NET_MPTCP_H */