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 #include <linux/bitops.h>
  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 #include <net/tcp_states.h>
  31
  32 /** struct ip_options - IP Options
  33  *
  34  * @faddr - Saved first hop address
  35  * @nexthop - Saved nexthop address in LSRR and SSRR
  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 #define ir_loc_addr             req.__req_common.skc_rcv_saddr
  75 #define ir_rmt_addr             req.__req_common.skc_daddr
  76 #define ir_num                  req.__req_common.skc_num
  77 #define ir_rmt_port             req.__req_common.skc_dport
  78 #define ir_v6_rmt_addr          req.__req_common.skc_v6_daddr
  79 #define ir_v6_loc_addr          req.__req_common.skc_v6_rcv_saddr
  80 #define ir_iif                  req.__req_common.skc_bound_dev_if
  81 #define ir_cookie               req.__req_common.skc_cookie
  82 #define ireq_net                req.__req_common.skc_net
  83 #define ireq_state              req.__req_common.skc_state
  84 #define ireq_family             req.__req_common.skc_family
  85
  86         kmemcheck_bitfield_begin(flags);
  87         u16                     snd_wscale : 4,
  88                                 rcv_wscale : 4,
  89                                 tstamp_ok  : 1,
  90                                 sack_ok    : 1,
  91                                 wscale_ok  : 1,
  92                                 ecn_ok     : 1,
  93                                 acked      : 1,
  94                                 no_srccheck: 1;
  95         kmemcheck_bitfield_end(flags);
  96         u32                     ir_mark;
  97         union {
  98                 struct ip_options_rcu   *opt;
  99                 struct sk_buff          *pktopts;
 100         };
 101 };
 102
 103 static inline struct inet_request_sock *inet_rsk(const struct request_sock *sk)
 104 {
 105         return (struct inet_request_sock *)sk;
 106 }
 107
 108 static inline u32 inet_request_mark(const struct sock *sk, struct sk_buff *skb)
 109 {
 110         if (!sk->sk_mark && sock_net(sk)->ipv4.sysctl_tcp_fwmark_accept)
 111                 return skb->mark;
 112
 113         return sk->sk_mark;
 114 }
 115
 116 struct inet_cork {
 117         unsigned int            flags;
 118         __be32                  addr;
 119         struct ip_options       *opt;
 120         unsigned int            fragsize;
 121         int                     length; /* Total length of all frames */
 122         struct dst_entry        *dst;
 123         u8                      tx_flags;
 124         __u8                    ttl;
 125         __s16                   tos;
 126         char                    priority;
 127 };
 128
 129 struct inet_cork_full {
 130         struct inet_cork        base;
 131         struct flowi            fl;
 132 };
 133
 134 struct ip_mc_socklist;
 135 struct ipv6_pinfo;
 136 struct rtable;
 137
 138 /** struct inet_sock - representation of INET sockets
 139  *
 140  * @sk - ancestor class
 141  * @pinet6 - pointer to IPv6 control block
 142  * @inet_daddr - Foreign IPv4 addr
 143  * @inet_rcv_saddr - Bound local IPv4 addr
 144  * @inet_dport - Destination port
 145  * @inet_num - Local port
 146  * @inet_saddr - Sending source
 147  * @uc_ttl - Unicast TTL
 148  * @inet_sport - Source port
 149  * @inet_id - ID counter for DF pkts
 150  * @tos - TOS
 151  * @mc_ttl - Multicasting TTL
 152  * @is_icsk - is this an inet_connection_sock?
 153  * @uc_index - Unicast outgoing device index
 154  * @mc_index - Multicast device index
 155  * @mc_list - Group array
 156  * @cork - info to build ip hdr on each ip frag while socket is corked
 157  */
 158 struct inet_sock {
 159         /* sk and pinet6 has to be the first two members of inet_sock */
 160         struct sock             sk;
 161 #if IS_ENABLED(CONFIG_IPV6)
 162         struct ipv6_pinfo       *pinet6;
 163 #endif
 164         /* Socket demultiplex comparisons on incoming packets. */
 165 #define inet_daddr              sk.__sk_common.skc_daddr
 166 #define inet_rcv_saddr          sk.__sk_common.skc_rcv_saddr
 167 #define inet_dport              sk.__sk_common.skc_dport
 168 #define inet_num                sk.__sk_common.skc_num
 169
 170         __be32                  inet_saddr;
 171         __s16                   uc_ttl;
 172         __u16                   cmsg_flags;
 173         __be16                  inet_sport;
 174         __u16                   inet_id;
 175
 176         struct ip_options_rcu __rcu     *inet_opt;
 177         int                     rx_dst_ifindex;
 178         __u8                    tos;
 179         __u8                    min_ttl;
 180         __u8                    mc_ttl;
 181         __u8                    pmtudisc;
 182         __u8                    recverr:1,
 183                                 is_icsk:1,
 184                                 freebind:1,
 185                                 hdrincl:1,
 186                                 mc_loop:1,
 187                                 transparent:1,
 188                                 mc_all:1,
 189                                 nodefrag:1;
 190         __u8                    bind_address_no_port:1;
 191         __u8                    rcv_tos;
 192         __u8                    convert_csum;
 193         int                     uc_index;
 194         int                     mc_index;
 195         __be32                  mc_addr;
 196         struct ip_mc_socklist __rcu     *mc_list;
 197         struct inet_cork_full   cork;
 198 };
 199
 200 #define IPCORK_OPT      1       /* ip-options has been held in ipcork.opt */
 201 #define IPCORK_ALLFRAG  2       /* always fragment (for ipv6 for now) */
 202
 203 /* cmsg flags for inet */
 204 #define IP_CMSG_PKTINFO         BIT(0)
 205 #define IP_CMSG_TTL             BIT(1)
 206 #define IP_CMSG_TOS             BIT(2)
 207 #define IP_CMSG_RECVOPTS        BIT(3)
 208 #define IP_CMSG_RETOPTS         BIT(4)
 209 #define IP_CMSG_PASSSEC         BIT(5)
 210 #define IP_CMSG_ORIGDSTADDR     BIT(6)
 211 #define IP_CMSG_CHECKSUM        BIT(7)
 212
 213 /* SYNACK messages might be attached to request sockets.
 214  * Some places want to reach the listener in this case.
 215  */
 216 static inline struct sock *skb_to_full_sk(const struct sk_buff *skb)
 217 {
 218         struct sock *sk = skb->sk;
 219
 220         if (sk && sk->sk_state == TCP_NEW_SYN_RECV)
 221                 sk = inet_reqsk(sk)->rsk_listener;
 222         return sk;
 223 }
 224
 225 static inline struct inet_sock *inet_sk(const struct sock *sk)
 226 {
 227         return (struct inet_sock *)sk;
 228 }
 229
 230 static inline void __inet_sk_copy_descendant(struct sock *sk_to,
 231                                              const struct sock *sk_from,
 232                                              const int ancestor_size)
 233 {
 234         memcpy(inet_sk(sk_to) + 1, inet_sk(sk_from) + 1,
 235                sk_from->sk_prot->obj_size - ancestor_size);
 236 }
 237 #if !(IS_ENABLED(CONFIG_IPV6))
 238 static inline void inet_sk_copy_descendant(struct sock *sk_to,
 239                                            const struct sock *sk_from)
 240 {
 241         __inet_sk_copy_descendant(sk_to, sk_from, sizeof(struct inet_sock));
 242 }
 243 #endif
 244
 245 int inet_sk_rebuild_header(struct sock *sk);
 246
 247 static inline unsigned int __inet_ehashfn(const __be32 laddr,
 248                                           const __u16 lport,
 249                                           const __be32 faddr,
 250                                           const __be16 fport,
 251                                           u32 initval)
 252 {
 253         return jhash_3words((__force __u32) laddr,
 254                             (__force __u32) faddr,
 255                             ((__u32) lport) << 16 | (__force __u32)fport,
 256                             initval);
 257 }
 258
 259 struct request_sock *inet_reqsk_alloc(const struct request_sock_ops *ops,
 260                                       struct sock *sk_listener,
 261                                       bool attach_listener);
 262
 263 static inline __u8 inet_sk_flowi_flags(const struct sock *sk)
 264 {
 265         __u8 flags = 0;
 266
 267         if (inet_sk(sk)->transparent || inet_sk(sk)->hdrincl)
 268                 flags |= FLOWI_FLAG_ANYSRC;
 269         return flags;
 270 }
 271
 272 static inline void inet_inc_convert_csum(struct sock *sk)
 273 {
 274         inet_sk(sk)->convert_csum++;
 275 }
 276
 277 static inline void inet_dec_convert_csum(struct sock *sk)
 278 {
 279         if (inet_sk(sk)->convert_csum > 0)
 280                 inet_sk(sk)->convert_csum--;
 281 }
 282
 283 static inline bool inet_get_convert_csum(struct sock *sk)
 284 {
 285         return !!inet_sk(sk)->convert_csum;
 286 }
 287
 288 #endif  /* _INET_SOCK_H */