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         u32                     ir_mark;
  92         struct ip_options_rcu   *opt;
  93 };
  94
  95 static inline struct inet_request_sock *inet_rsk(const struct request_sock *sk)
  96 {
  97         return (struct inet_request_sock *)sk;
  98 }
  99
 100 static inline u32 inet_request_mark(struct sock *sk, struct sk_buff *skb)
 101 {
 102         if (!sk->sk_mark && sock_net(sk)->ipv4.sysctl_tcp_fwmark_accept)
 103                 return skb->mark;
 104
 105         return sk->sk_mark;
 106 }
 107
 108 struct inet_cork {
 109         unsigned int            flags;
 110         __be32                  addr;
 111         struct ip_options       *opt;
 112         unsigned int            fragsize;
 113         int                     length; /* Total length of all frames */
 114         struct dst_entry        *dst;
 115         u8                      tx_flags;
 116 };
 117
 118 struct inet_cork_full {
 119         struct inet_cork        base;
 120         struct flowi            fl;
 121 };
 122
 123 struct ip_mc_socklist;
 124 struct ipv6_pinfo;
 125 struct rtable;
 126
 127 /** struct inet_sock - representation of INET sockets
 128  *
 129  * @sk - ancestor class
 130  * @pinet6 - pointer to IPv6 control block
 131  * @inet_daddr - Foreign IPv4 addr
 132  * @inet_rcv_saddr - Bound local IPv4 addr
 133  * @inet_dport - Destination port
 134  * @inet_num - Local port
 135  * @inet_saddr - Sending source
 136  * @uc_ttl - Unicast TTL
 137  * @inet_sport - Source port
 138  * @inet_id - ID counter for DF pkts
 139  * @tos - TOS
 140  * @mc_ttl - Multicasting TTL
 141  * @is_icsk - is this an inet_connection_sock?
 142  * @uc_index - Unicast outgoing device index
 143  * @mc_index - Multicast device index
 144  * @mc_list - Group array
 145  * @cork - info to build ip hdr on each ip frag while socket is corked
 146  */
 147 struct inet_sock {
 148         /* sk and pinet6 has to be the first two members of inet_sock */
 149         struct sock             sk;
 150 #if IS_ENABLED(CONFIG_IPV6)
 151         struct ipv6_pinfo       *pinet6;
 152 #endif
 153         /* Socket demultiplex comparisons on incoming packets. */
 154 #define inet_daddr              sk.__sk_common.skc_daddr
 155 #define inet_rcv_saddr          sk.__sk_common.skc_rcv_saddr
 156 #define inet_addrpair           sk.__sk_common.skc_addrpair
 157 #define inet_dport              sk.__sk_common.skc_dport
 158 #define inet_num                sk.__sk_common.skc_num
 159 #define inet_portpair           sk.__sk_common.skc_portpair
 160
 161         __be32                  inet_saddr;
 162         __s16                   uc_ttl;
 163         __u16                   cmsg_flags;
 164         __be16                  inet_sport;
 165         __u16                   inet_id;
 166
 167         struct ip_options_rcu __rcu     *inet_opt;
 168         int                     rx_dst_ifindex;
 169         __u8                    tos;
 170         __u8                    min_ttl;
 171         __u8                    mc_ttl;
 172         __u8                    pmtudisc;
 173         __u8                    recverr:1,
 174                                 is_icsk:1,
 175                                 freebind:1,
 176                                 hdrincl:1,
 177                                 mc_loop:1,
 178                                 transparent:1,
 179                                 mc_all:1,
 180                                 nodefrag:1;
 181         __u8                    rcv_tos;
 182         int                     uc_index;
 183         int                     mc_index;
 184         __be32                  mc_addr;
 185         struct ip_mc_socklist __rcu     *mc_list;
 186         struct inet_cork_full   cork;
 187 };
 188
 189 #define IPCORK_OPT      1       /* ip-options has been held in ipcork.opt */
 190 #define IPCORK_ALLFRAG  2       /* always fragment (for ipv6 for now) */
 191
 192 static inline struct inet_sock *inet_sk(const struct sock *sk)
 193 {
 194         return (struct inet_sock *)sk;
 195 }
 196
 197 static inline void __inet_sk_copy_descendant(struct sock *sk_to,
 198                                              const struct sock *sk_from,
 199                                              const int ancestor_size)
 200 {
 201         memcpy(inet_sk(sk_to) + 1, inet_sk(sk_from) + 1,
 202                sk_from->sk_prot->obj_size - ancestor_size);
 203 }
 204 #if !(IS_ENABLED(CONFIG_IPV6))
 205 static inline void inet_sk_copy_descendant(struct sock *sk_to,
 206                                            const struct sock *sk_from)
 207 {
 208         __inet_sk_copy_descendant(sk_to, sk_from, sizeof(struct inet_sock));
 209 }
 210 #endif
 211
 212 extern int inet_sk_rebuild_header(struct sock *sk);
 213
 214 extern u32 inet_ehash_secret;
 215 extern u32 ipv6_hash_secret;
 216 extern void build_ehash_secret(void);
 217
 218 static inline unsigned int inet_ehashfn(struct net *net,
 219                                         const __be32 laddr, const __u16 lport,
 220                                         const __be32 faddr, const __be16 fport)
 221 {
 222         return jhash_3words((__force __u32) laddr,
 223                             (__force __u32) faddr,
 224                             ((__u32) lport) << 16 | (__force __u32)fport,
 225                             inet_ehash_secret + net_hash_mix(net));
 226 }
 227
 228 static inline int inet_sk_ehashfn(const struct sock *sk)
 229 {
 230         const struct inet_sock *inet = inet_sk(sk);
 231         const __be32 laddr = inet->inet_rcv_saddr;
 232         const __u16 lport = inet->inet_num;
 233         const __be32 faddr = inet->inet_daddr;
 234         const __be16 fport = inet->inet_dport;
 235         struct net *net = sock_net(sk);
 236
 237         return inet_ehashfn(net, laddr, lport, faddr, fport);
 238 }
 239
 240 static inline struct request_sock *inet_reqsk_alloc(struct request_sock_ops *ops)
 241 {
 242         struct request_sock *req = reqsk_alloc(ops);
 243         struct inet_request_sock *ireq = inet_rsk(req);
 244
 245         if (req != NULL) {
 246                 kmemcheck_annotate_bitfield(ireq, flags);
 247                 ireq->opt = NULL;
 248         }
 249
 250         return req;
 251 }
 252
 253 static inline __u8 inet_sk_flowi_flags(const struct sock *sk)
 254 {
 255         __u8 flags = 0;
 256
 257         if (inet_sk(sk)->transparent || inet_sk(sk)->hdrincl)
 258                 flags |= FLOWI_FLAG_ANYSRC;
 259         return flags;
 260 }
 261
 262 #endif  /* _INET_SOCK_H */