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 #define MPTCP_RM_IDS_MAX 8
39 struct mptcp_rm_list {
40 u8 ids[MPTCP_RM_IDS_MAX];
44 struct mptcp_addr_info {
50 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
51 struct in6_addr addr6;
56 struct mptcp_out_options {
57 #if IS_ENABLED(CONFIG_MPTCP)
62 struct mptcp_addr_info addr;
63 struct mptcp_rm_list rm_list;
72 struct mptcp_ext ext_copy;
77 extern struct request_sock_ops mptcp_subflow_request_sock_ops;
79 void mptcp_init(void);
81 static inline bool sk_is_mptcp(const struct sock *sk)
83 return tcp_sk(sk)->is_mptcp;
86 static inline bool rsk_is_mptcp(const struct request_sock *req)
88 return tcp_rsk(req)->is_mptcp;
91 static inline bool rsk_drop_req(const struct request_sock *req)
93 return tcp_rsk(req)->is_mptcp && tcp_rsk(req)->drop_req;
96 void mptcp_space(const struct sock *ssk, int *space, int *full_space);
97 bool mptcp_syn_options(struct sock *sk, const struct sk_buff *skb,
98 unsigned int *size, struct mptcp_out_options *opts);
99 bool mptcp_synack_options(const struct request_sock *req, unsigned int *size,
100 struct mptcp_out_options *opts);
101 bool mptcp_established_options(struct sock *sk, struct sk_buff *skb,
102 unsigned int *size, unsigned int remaining,
103 struct mptcp_out_options *opts);
104 void mptcp_incoming_options(struct sock *sk, struct sk_buff *skb);
106 void mptcp_write_options(__be32 *ptr, const struct tcp_sock *tp,
107 struct mptcp_out_options *opts);
109 /* move the skb extension owership, with the assumption that 'to' is
112 static inline void mptcp_skb_ext_move(struct sk_buff *to,
113 struct sk_buff *from)
115 if (!skb_ext_exist(from, SKB_EXT_MPTCP))
118 if (WARN_ON_ONCE(to->active_extensions))
121 to->active_extensions = from->active_extensions;
122 to->extensions = from->extensions;
123 from->active_extensions = 0;
126 static inline void mptcp_skb_ext_copy(struct sk_buff *to,
127 struct sk_buff *from)
129 struct mptcp_ext *from_ext;
131 from_ext = skb_ext_find(from, SKB_EXT_MPTCP);
135 from_ext->frozen = 1;
136 skb_ext_copy(to, from);
139 static inline bool mptcp_ext_matches(const struct mptcp_ext *to_ext,
140 const struct mptcp_ext *from_ext)
142 /* MPTCP always clears the ext when adding it to the skb, so
143 * holes do not bother us here
146 (to_ext && from_ext &&
147 !memcmp(from_ext, to_ext, sizeof(struct mptcp_ext)));
150 /* check if skbs can be collapsed.
151 * MPTCP collapse is allowed if neither @to or @from carry an mptcp data
152 * mapping, or if the extension of @to is the same as @from.
153 * Collapsing is not possible if @to lacks an extension, but @from carries one.
155 static inline bool mptcp_skb_can_collapse(const struct sk_buff *to,
156 const struct sk_buff *from)
158 return mptcp_ext_matches(skb_ext_find(to, SKB_EXT_MPTCP),
159 skb_ext_find(from, SKB_EXT_MPTCP));
162 void mptcp_seq_show(struct seq_file *seq);
163 int mptcp_subflow_init_cookie_req(struct request_sock *req,
164 const struct sock *sk_listener,
165 struct sk_buff *skb);
167 __be32 mptcp_get_reset_option(const struct sk_buff *skb);
169 static inline __be32 mptcp_reset_option(const struct sk_buff *skb)
171 if (skb_ext_exist(skb, SKB_EXT_MPTCP))
172 return mptcp_get_reset_option(skb);
178 static inline void mptcp_init(void)
182 static inline bool sk_is_mptcp(const struct sock *sk)
187 static inline bool rsk_is_mptcp(const struct request_sock *req)
192 static inline bool rsk_drop_req(const struct request_sock *req)
197 static inline void mptcp_parse_option(const struct sk_buff *skb,
198 const unsigned char *ptr, int opsize,
199 struct tcp_options_received *opt_rx)
203 static inline bool mptcp_syn_options(struct sock *sk, const struct sk_buff *skb,
205 struct mptcp_out_options *opts)
210 static inline bool mptcp_synack_options(const struct request_sock *req,
212 struct mptcp_out_options *opts)
217 static inline bool mptcp_established_options(struct sock *sk,
220 unsigned int remaining,
221 struct mptcp_out_options *opts)
226 static inline void mptcp_incoming_options(struct sock *sk,
231 static inline void mptcp_skb_ext_move(struct sk_buff *to,
232 const struct sk_buff *from)
236 static inline void mptcp_skb_ext_copy(struct sk_buff *to,
237 struct sk_buff *from)
241 static inline bool mptcp_skb_can_collapse(const struct sk_buff *to,
242 const struct sk_buff *from)
247 static inline void mptcp_space(const struct sock *ssk, int *s, int *fs) { }
248 static inline void mptcp_seq_show(struct seq_file *seq) { }
250 static inline int mptcp_subflow_init_cookie_req(struct request_sock *req,
251 const struct sock *sk_listener,
254 return 0; /* TCP fallback */
257 static inline __be32 mptcp_reset_option(const struct sk_buff *skb) { return htonl(0u); }
258 #endif /* CONFIG_MPTCP */
260 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
261 int mptcpv6_init(void);
262 void mptcpv6_handle_mapped(struct sock *sk, bool mapped);
263 #elif IS_ENABLED(CONFIG_IPV6)
264 static inline int mptcpv6_init(void) { return 0; }
265 static inline void mptcpv6_handle_mapped(struct sock *sk, bool mapped) { }
268 #endif /* __NET_MPTCP_H */