include/net/inet_sock.h

   1 /*
   2  * INET         An implementation of the TCP/IP protocol suite for the LINUX
   3  *              operating system.  INET is implemented using the  BSD Socket
   4  *              interface as the means of communication with the user level.
   5  *
   6  *              Definitions for inet_sock
   7  *
   8  * Authors:     Many, reorganised here by
   9  *              Arnaldo Carvalho de Melo <acme@mandriva.com>
  10  *
  11  *              This program is free software; you can redistribute it and/or
  12  *              modify it under the terms of the GNU General Public License
  13  *              as published by the Free Software Foundation; either version
  14  *              2 of the License, or (at your option) any later version.
  15  */
  16 #ifndef _INET_SOCK_H
  17 #define _INET_SOCK_H
  18
  19
  20 #include <linux/kmemcheck.h>
  21 #include <linux/string.h>
  22 #include <linux/types.h>
  23 #include <linux/jhash.h>
  24 #include <linux/netdevice.h>
  25
  26 #include <net/flow.h>
  27 #include <net/sock.h>
  28 #include <net/request_sock.h>
  29 #include <net/netns/hash.h>
  30
  31 /** struct ip_options - IP Options
  32  *
  33  * @faddr - Saved first hop address
  34  * @nexthop - Saved nexthop address in LSRR and SSRR
  35  * @is_data - Options in __data, rather than skb
  36  * @is_strictroute - Strict source route
  37  * @srr_is_hit - Packet destination addr was our one
  38  * @is_changed - IP checksum more not valid
  39  * @rr_needaddr - Need to record addr of outgoing dev
  40  * @ts_needtime - Need to record timestamp
  41  * @ts_needaddr - Need to record addr of outgoing dev
  42  */
  43 struct ip_options {
  44         __be32          faddr;
  45         __be32          nexthop;
  46         unsigned char   optlen;
  47         unsigned char   srr;
  48         unsigned char   rr;
  49         unsigned char   ts;
  50         unsigned char   is_strictroute:1,
  51                         srr_is_hit:1,
  52                         is_changed:1,
  53                         rr_needaddr:1,
  54                         ts_needtime:1,
  55                         ts_needaddr:1;
  56         unsigned char   router_alert;
  57         unsigned char   cipso;
  58         unsigned char   __pad2;
  59         unsigned char   __data[0];
  60 };
  61
  62 struct ip_options_rcu {
  63         struct rcu_head rcu;
  64         struct ip_options opt;
  65 };
  66
  67 struct ip_options_data {
  68         struct ip_options_rcu   opt;
  69         char                    data[40];
  70 };
  71
  72 struct inet_request_sock {
  73         struct request_sock     req;
  74 #if IS_ENABLED(CONFIG_IPV6)
  75         u16                     inet6_rsk_offset;
  76 #endif
  77         __be16                  loc_port;
  78         __be32                  loc_addr;
  79         __be32                  rmt_addr;
  80         __be16                  rmt_port;
  81         kmemcheck_bitfield_begin(flags);
  82         u16                     snd_wscale : 4,
  83                                 rcv_wscale : 4,
  84                                 tstamp_ok  : 1,
  85                                 sack_ok    : 1,
  86                                 wscale_ok  : 1,
  87                                 ecn_ok     : 1,
  88                                 acked      : 1,
  89                                 no_srccheck: 1;
  90         kmemcheck_bitfield_end(flags);
  91         struct ip_options_rcu   *opt;
  92 };
  93
  94 static inline struct inet_request_sock *inet_rsk(const struct request_sock *sk)
  95 {
  96         return (struct inet_request_sock *)sk;
  97 }
  98
  99 struct inet_cork {
 100         unsigned int            flags;
 101         __be32                  addr;
 102         struct ip_options       *opt;
 103         unsigned int            fragsize;
 104         struct dst_entry        *dst;
 105         int                     length; /* Total length of all frames */
 106         struct page             *page;
 107         u32                     off;
 108         u8                      tx_flags;
 109 };
 110
 111 struct inet_cork_full {
 112         struct inet_cork        base;
 113         struct flowi            fl;
 114 };
 115
 116 struct ip_mc_socklist;
 117 struct ipv6_pinfo;
 118 struct rtable;
 119
 120 /** struct inet_sock - representation of INET sockets
 121  *
 122  * @sk - ancestor class
 123  * @pinet6 - pointer to IPv6 control block
 124  * @inet_daddr - Foreign IPv4 addr
 125  * @inet_rcv_saddr - Bound local IPv4 addr
 126  * @inet_dport - Destination port
 127  * @inet_num - Local port
 128  * @inet_saddr - Sending source
 129  * @uc_ttl - Unicast TTL
 130  * @inet_sport - Source port
 131  * @inet_id - ID counter for DF pkts
 132  * @tos - TOS
 133  * @mc_ttl - Multicasting TTL
 134  * @is_icsk - is this an inet_connection_sock?
 135  * @uc_index - Unicast outgoing device index
 136  * @mc_index - Multicast device index
 137  * @mc_list - Group array
 138  * @cork - info to build ip hdr on each ip frag while socket is corked
 139  */
 140 struct inet_sock {
 141         /* sk and pinet6 has to be the first two members of inet_sock */
 142         struct sock             sk;
 143 #if IS_ENABLED(CONFIG_IPV6)
 144         struct ipv6_pinfo       *pinet6;
 145 #endif
 146         /* Socket demultiplex comparisons on incoming packets. */
 147 #define inet_daddr              sk.__sk_common.skc_daddr
 148 #define inet_rcv_saddr          sk.__sk_common.skc_rcv_saddr
 149
 150         __be16                  inet_dport;
 151         __u16                   inet_num;
 152         __be32                  inet_saddr;
 153         __s16                   uc_ttl;
 154         __u16                   cmsg_flags;
 155         __be16                  inet_sport;
 156         __u16                   inet_id;
 157
 158         struct ip_options_rcu __rcu     *inet_opt;
 159         __u8                    tos;
 160         __u8                    min_ttl;
 161         __u8                    mc_ttl;
 162         __u8                    pmtudisc;
 163         __u8                    recverr:1,
 164                                 is_icsk:1,
 165                                 freebind:1,
 166                                 hdrincl:1,
 167                                 mc_loop:1,
 168                                 transparent:1,
 169                                 mc_all:1,
 170                                 nodefrag:1;
 171         __u8                    rcv_tos;
 172         int                     uc_index;
 173         int                     mc_index;
 174         __be32                  mc_addr;
 175         struct ip_mc_socklist __rcu     *mc_list;
 176         struct inet_cork_full   cork;
 177 };
 178
 179 #define IPCORK_OPT      1       /* ip-options has been held in ipcork.opt */
 180 #define IPCORK_ALLFRAG  2       /* always fragment (for ipv6 for now) */
 181
 182 static inline struct inet_sock *inet_sk(const struct sock *sk)
 183 {
 184         return (struct inet_sock *)sk;
 185 }
 186
 187 static inline void __inet_sk_copy_descendant(struct sock *sk_to,
 188                                              const struct sock *sk_from,
 189                                              const int ancestor_size)
 190 {
 191         memcpy(inet_sk(sk_to) + 1, inet_sk(sk_from) + 1,
 192                sk_from->sk_prot->obj_size - ancestor_size);
 193 }
 194 #if !(IS_ENABLED(CONFIG_IPV6))
 195 static inline void inet_sk_copy_descendant(struct sock *sk_to,
 196                                            const struct sock *sk_from)
 197 {
 198         __inet_sk_copy_descendant(sk_to, sk_from, sizeof(struct inet_sock));
 199 }
 200 #endif
 201
 202 extern int inet_sk_rebuild_header(struct sock *sk);
 203
 204 extern u32 inet_ehash_secret;
 205 extern void build_ehash_secret(void);
 206
 207 static inline unsigned int inet_ehashfn(struct net *net,
 208                                         const __be32 laddr, const __u16 lport,
 209                                         const __be32 faddr, const __be16 fport)
 210 {
 211         return jhash_3words((__force __u32) laddr,
 212                             (__force __u32) faddr,
 213                             ((__u32) lport) << 16 | (__force __u32)fport,
 214                             inet_ehash_secret + net_hash_mix(net));
 215 }
 216
 217 static inline int inet_sk_ehashfn(const struct sock *sk)
 218 {
 219         const struct inet_sock *inet = inet_sk(sk);
 220         const __be32 laddr = inet->inet_rcv_saddr;
 221         const __u16 lport = inet->inet_num;
 222         const __be32 faddr = inet->inet_daddr;
 223         const __be16 fport = inet->inet_dport;
 224         struct net *net = sock_net(sk);
 225
 226         return inet_ehashfn(net, laddr, lport, faddr, fport);
 227 }
 228
 229 static inline struct request_sock *inet_reqsk_alloc(struct request_sock_ops *ops)
 230 {
 231         struct request_sock *req = reqsk_alloc(ops);
 232         struct inet_request_sock *ireq = inet_rsk(req);
 233
 234         if (req != NULL) {
 235                 kmemcheck_annotate_bitfield(ireq, flags);
 236                 ireq->opt = NULL;
 237         }
 238
 239         return req;
 240 }
 241
 242 static inline __u8 inet_sk_flowi_flags(const struct sock *sk)
 243 {
 244         __u8 flags = 0;
 245
 246         if (inet_sk(sk)->transparent || inet_sk(sk)->hdrincl)
 247                 flags |= FLOWI_FLAG_ANYSRC;
 248         if (sk->sk_protocol == IPPROTO_TCP)
 249                 flags |= FLOWI_FLAG_PRECOW_METRICS;
 250         return flags;
 251 }
 252
 253 #endif  /* _INET_SOCK_H */