Line data    Source code

       1             : /* SPDX-License-Identifier: GPL-2.0-or-later */
       2             : /*
       3             :  * INET         An implementation of the TCP/IP protocol suite for the LINUX
       4             :  *              operating system.  INET is implemented using the  BSD Socket
       5             :  *              interface as the means of communication with the user level.
       6             :  *
       7             :  *              Definitions for the UDP protocol.
       8             :  *
       9             :  * Version:     @(#)udp.h       1.0.2   04/28/93
      10             :  *
      11             :  * Author:      Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
      12             :  */
      13             : #ifndef _LINUX_UDP_H
      14             : #define _LINUX_UDP_H
      15             : 
      16             : #include <net/inet_sock.h>
      17             : #include <linux/skbuff.h>
      18             : #include <net/netns/hash.h>
      19             : #include <uapi/linux/udp.h>
      20             : 
      21          22 : static inline struct udphdr *udp_hdr(const struct sk_buff *skb)
      22             : {
      23          22 :         return (struct udphdr *)skb_transport_header(skb);
      24             : }
      25             : 
      26             : static inline struct udphdr *inner_udp_hdr(const struct sk_buff *skb)
      27             : {
      28             :         return (struct udphdr *)skb_inner_transport_header(skb);
      29             : }
      30             : 
      31             : #define UDP_HTABLE_SIZE_MIN             (CONFIG_BASE_SMALL ? 128 : 256)
      32             : 
      33          82 : static inline u32 udp_hashfn(const struct net *net, u32 num, u32 mask)
      34             : {
      35          82 :         return (num + net_hash_mix(net)) & mask;
      36             : }
      37             : 
      38             : struct udp_sock {
      39             :         /* inet_sock has to be the first member */
      40             :         struct inet_sock inet;
      41             : #define udp_port_hash           inet.sk.__sk_common.skc_u16hashes[0]
      42             : #define udp_portaddr_hash       inet.sk.__sk_common.skc_u16hashes[1]
      43             : #define udp_portaddr_node       inet.sk.__sk_common.skc_portaddr_node
      44             :         int              pending;       /* Any pending frames ? */
      45             :         unsigned int     corkflag;      /* Cork is required */
      46             :         __u8             encap_type;    /* Is this an Encapsulation socket? */
      47             :         unsigned char    no_check6_tx:1,/* Send zero UDP6 checksums on TX? */
      48             :                          no_check6_rx:1,/* Allow zero UDP6 checksums on RX? */
      49             :                          encap_enabled:1, /* This socket enabled encap
      50             :                                            * processing; UDP tunnels and
      51             :                                            * different encapsulation layer set
      52             :                                            * this
      53             :                                            */
      54             :                          gro_enabled:1; /* Can accept GRO packets */
      55             :         /*
      56             :          * Following member retains the information to create a UDP header
      57             :          * when the socket is uncorked.
      58             :          */
      59             :         __u16            len;           /* total length of pending frames */
      60             :         __u16            gso_size;
      61             :         /*
      62             :          * Fields specific to UDP-Lite.
      63             :          */
      64             :         __u16            pcslen;
      65             :         __u16            pcrlen;
      66             : /* indicator bits used by pcflag: */
      67             : #define UDPLITE_BIT      0x1            /* set by udplite proto init function */
      68             : #define UDPLITE_SEND_CC  0x2            /* set via udplite setsockopt         */
      69             : #define UDPLITE_RECV_CC  0x4            /* set via udplite setsocktopt        */
      70             :         __u8             pcflag;        /* marks socket as UDP-Lite if > 0    */
      71             :         __u8             unused[3];
      72             :         /*
      73             :          * For encapsulation sockets.
      74             :          */
      75             :         int (*encap_rcv)(struct sock *sk, struct sk_buff *skb);
      76             :         int (*encap_err_lookup)(struct sock *sk, struct sk_buff *skb);
      77             :         void (*encap_destroy)(struct sock *sk);
      78             : 
      79             :         /* GRO functions for UDP socket */
      80             :         struct sk_buff *        (*gro_receive)(struct sock *sk,
      81             :                                                struct list_head *head,
      82             :                                                struct sk_buff *skb);
      83             :         int                     (*gro_complete)(struct sock *sk,
      84             :                                                 struct sk_buff *skb,
      85             :                                                 int nhoff);
      86             : 
      87             :         /* udp_recvmsg try to use this before splicing sk_receive_queue */
      88             :         struct sk_buff_head     reader_queue ____cacheline_aligned_in_smp;
      89             : 
      90             :         /* This field is dirtied by udp_recvmsg() */
      91             :         int             forward_deficit;
      92             : };
      93             : 
      94             : #define UDP_MAX_SEGMENTS        (1 << 6UL)
      95             : 
      96         565 : static inline struct udp_sock *udp_sk(const struct sock *sk)
      97             : {
      98         515 :         return (struct udp_sock *)sk;
      99             : }
     100             : 
     101             : static inline void udp_set_no_check6_tx(struct sock *sk, bool val)
     102             : {
     103             :         udp_sk(sk)->no_check6_tx = val;
     104             : }
     105             : 
     106             : static inline void udp_set_no_check6_rx(struct sock *sk, bool val)
     107             : {
     108             :         udp_sk(sk)->no_check6_rx = val;
     109             : }
     110             : 
     111             : static inline bool udp_get_no_check6_tx(struct sock *sk)
     112             : {
     113             :         return udp_sk(sk)->no_check6_tx;
     114             : }
     115             : 
     116             : static inline bool udp_get_no_check6_rx(struct sock *sk)
     117             : {
     118             :         return udp_sk(sk)->no_check6_rx;
     119             : }
     120             : 
     121           0 : static inline void udp_cmsg_recv(struct msghdr *msg, struct sock *sk,
     122             :                                  struct sk_buff *skb)
     123             : {
     124           0 :         int gso_size;
     125             : 
     126           0 :         if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) {
     127           0 :                 gso_size = skb_shinfo(skb)->gso_size;
     128           0 :                 put_cmsg(msg, SOL_UDP, UDP_GRO, sizeof(gso_size), &gso_size);
     129             :         }
     130           0 : }
     131             : 
     132           2 : static inline bool udp_unexpected_gso(struct sock *sk, struct sk_buff *skb)
     133             : {
     134           2 :         return !udp_sk(sk)->gro_enabled && skb_is_gso(skb) &&
     135           0 :                skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4;
     136             : }
     137             : 
     138             : #define udp_portaddr_for_each_entry(__sk, list) \
     139             :         hlist_for_each_entry(__sk, list, __sk_common.skc_portaddr_node)
     140             : 
     141             : #define udp_portaddr_for_each_entry_rcu(__sk, list) \
     142             :         hlist_for_each_entry_rcu(__sk, list, __sk_common.skc_portaddr_node)
     143             : 
     144             : #define IS_UDPLITE(__sk) (__sk->sk_protocol == IPPROTO_UDPLITE)
     145             : 
     146             : #endif  /* _LINUX_UDP_H */