0x00 "lm_J*j"Tf]jbѿ h0 B l4( (  fB- _I|+am_J*j"Tf]ˊbѿ? /* SPDX-License-Identifier: GPL-2.0-or-later */ /* * INET An implementation of the TCP/IP protocol suite for the LINUX * operating system. INET is implemented using the BSD Socket * interface as the means of communication with the user level. * * Definitions for the TCP protocol. * * Version: @(#)tcp.h 1.0.2 04/28/93 * * Author: Fred N. van Kempen, */ #ifndef _LINUX_TCP_H #define _LINUX_TCP_H #include #include #include #include #include #include static inline struct tcphdr *tcp_hdr(const struct sk_buff *skb) { return (struct tcphdr *)skb_transport_header(skb); } static inline unsigned int __tcp_hdrlen(const struct tcphdr *th) { return th->doff * 4; } static inline unsigned int tcp_hdrlen(const struct sk_buff *skb) { return __tcp_hdrlen(tcp_hdr(skb)); } static inline struct tcphdr *inner_tcp_hdr(const struct sk_buff *skb) { return (struct tcphdr *)skb_inner_transport_header(skb); } static inline unsigned int inner_tcp_hdrlen(const struct sk_buff *skb) { return inner_tcp_hdr(skb)->doff * 4; } /** * skb_tcp_all_headers - Returns size of all headers for a TCP packet * @skb: buffer * * Used in TX path, for a packet known to be a TCP one. * * if (skb_is_gso(skb)) { * int hlen = skb_tcp_all_headers(skb); * ... */ static inline int skb_tcp_all_headers(const struct sk_buff *skb) { return skb_transport_offset(skb) + tcp_hdrlen(skb); } /** * skb_inner_tcp_all_headers - Returns size of all headers for an encap TCP packet * @skb: buffer * * Used in TX path, for a packet known to be a TCP one. * * if (skb_is_gso(skb) && skb->encapsulation) { * int hlen = skb_inner_tcp_all_headers(skb); * ... */ static inline int skb_inner_tcp_all_headers(const struct sk_buff *skb) { return skb_inner_transport_offset(skb) + inner_tcp_hdrlen(skb); } static inline unsigned int tcp_optlen(const struct sk_buff *skb) { return (tcp_hdr(skb)->doff - 5) * 4; } /* TCP Fast Open */ #define TCP_FASTOPEN_COOKIE_MIN 4 /* Min Fast Open Cookie size in bytes */ #define TCP_FASTOPEN_COOKIE_MAX 16 /* Max Fast Open Cookie size in bytes */ #define TCP_FASTOPEN_COOKIE_SIZE 8 /* the size employed by this impl. */ /* TCP Fast Open Cookie as stored in memory */ struct tcp_fastopen_cookie { __le64 val[DIV_ROUND_UP(TCP_FASTOPEN_COOKIE_MAX, sizeof(u64))]; s8 len; bool exp; /* In RFC6994 experimental option format */ }; /* This defines a selective acknowledgement block. */ struct tcp_sack_block_wire { __be32 start_seq; __be32 end_seq; }; struct tcp_sack_block { u32 start_seq; u32 end_seq; }; /*These are used to set the sack_ok field in struct tcp_options_received */ #define TCP_SACK_SEEN (1 << 0) /*1 = peer is SACK capable, */ #define TCP_DSACK_SEEN (1 << 2) /*1 = DSACK was received from peer*/ struct tcp_options_received { /* PAWS/RTTM data */ int ts_recent_stamp;/* Time we stored ts_recent (for aging) */ u32 ts_recent; /* Time stamp to echo next */ u32 rcv_tsval; /* Time stamp value */ u32 rcv_tsecr; /* Time stamp echo reply */ u16 saw_tstamp : 1, /* Saw TIMESTAMP on last packet */ tstamp_ok : 1, /* TIMESTAMP seen on SYN packet */ dsack : 1, /* D-SACK is scheduled */ wscale_ok : 1, /* Wscale seen on SYN packet */ sack_ok : 3, /* SACK seen on SYN packet */ smc_ok : 1, /* SMC seen on SYN packet */ snd_wscale : 4, /* Window scaling received from sender */ rcv_wscale : 4; /* Window scaling to send to receiver */ u8 saw_unknown:1, /* Received unknown option */ unused:7; u8 num_sacks; /* Number of SACK blocks */ u16 user_mss; /* mss requested by user in ioctl */ u16 mss_clamp; /* Maximal mss, negotiated at connection setup */ }; static inline void tcp_clear_options(struct tcp_options_received *rx_opt) { rx_opt->tstamp_ok = rx_o