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 the UDP module. 7 * 8 * Version: @(#)udp.h 1.0.2 05/07/93 9 * 10 * Authors: Ross Biro 11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 12 * 13 * Fixes: 14 * Alan Cox : Turned on udp checksums. I don't want to 15 * chase 'memory corruption' bugs that aren't! 16 * 17 * This program is free software; you can redistribute it and/or 18 * modify it under the terms of the GNU General Public License 19 * as published by the Free Software Foundation; either version 20 * 2 of the License, or (at your option) any later version. 21 */ 22 #ifndef _UDP_H 23 #define _UDP_H 24 25 #include <linux/list.h> 26 #include <net/inet_sock.h> 27 #include <net/sock.h> 28 #include <net/snmp.h> 29 #include <net/ip.h> 30 #include <linux/ipv6.h> 31 #include <linux/seq_file.h> 32 #include <linux/poll.h> 33 34 /** 35 * struct udp_skb_cb - UDP(-Lite) private variables 36 * 37 * @header: private variables used by IPv4/IPv6 38 * @cscov: checksum coverage length (UDP-Lite only) 39 * @partial_cov: if set indicates partial csum coverage 40 */ 41 struct udp_skb_cb { 42 union { 43 struct inet_skb_parm h4; 44 #if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE) 45 struct inet6_skb_parm h6; 46 #endif 47 } header; 48 __u16 cscov; 49 __u8 partial_cov; 50 }; 51 #define UDP_SKB_CB(__skb) ((struct udp_skb_cb *)((__skb)->cb)) 52 53 extern struct hlist_head udp_hash[UDP_HTABLE_SIZE]; 54 extern rwlock_t udp_hash_lock; 55 56 57 /* Note: this must match 'valbool' in sock_setsockopt */ 58 #define UDP_CSUM_NOXMIT 1 59 60 /* Used by SunRPC/xprt layer. */ 61 #define UDP_CSUM_NORCV 2 62 63 /* Default, as per the RFC, is to always do csums. */ 64 #define UDP_CSUM_DEFAULT 0 65 66 extern struct proto udp_prot; 67 68 extern atomic_t udp_memory_allocated; 69 70 /* sysctl variables for udp */ 71 extern int sysctl_udp_mem[3]; 72 extern int sysctl_udp_rmem_min; 73 extern int sysctl_udp_wmem_min; 74 75 struct sk_buff; 76 77 /* 78 * Generic checksumming routines for UDP(-Lite) v4 and v6 79 */ 80 static inline __sum16 __udp_lib_checksum_complete(struct sk_buff *skb) 81 { 82 return __skb_checksum_complete_head(skb, UDP_SKB_CB(skb)->cscov); 83 } 84 85 static inline int udp_lib_checksum_complete(struct sk_buff *skb) 86 { 87 return !skb_csum_unnecessary(skb) && 88 __udp_lib_checksum_complete(skb); 89 } 90 91 /** 92 * udp_csum_outgoing - compute UDPv4/v6 checksum over fragments 93 * @sk: socket we are writing to 94 * @skb: sk_buff containing the filled-in UDP header 95 * (checksum field must be zeroed out) 96 */ 97 static inline __wsum udp_csum_outgoing(struct sock *sk, struct sk_buff *skb) 98 { 99 __wsum csum = csum_partial(skb_transport_header(skb), 100 sizeof(struct udphdr), 0); 101 skb_queue_walk(&sk->sk_write_queue, skb) { 102 csum = csum_add(csum, skb->csum); 103 } 104 return csum; 105 } 106 107 /* hash routines shared between UDPv4/6 and UDP-Litev4/6 */ 108 static inline void udp_lib_hash(struct sock *sk) 109 { 110 BUG(); 111 } 112 113 static inline void udp_lib_unhash(struct sock *sk) 114 { 115 write_lock_bh(&udp_hash_lock); 116 if (sk_del_node_init(sk)) { 117 inet_sk(sk)->num = 0; 118 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1); 119 } 120 write_unlock_bh(&udp_hash_lock); 121 } 122 123 static inline void udp_lib_close(struct sock *sk, long timeout) 124 { 125 sk_common_release(sk); 126 } 127 128 extern int udp_lib_get_port(struct sock *sk, unsigned short snum, 129 int (*)(const struct sock*,const struct sock*)); 130 131 /* net/ipv4/udp.c */ 132 extern int udp_get_port(struct sock *sk, unsigned short snum, 133 int (*saddr_cmp)(const struct sock *, const struct sock *)); 134 extern void udp_err(struct sk_buff *, u32); 135 136 extern int udp_sendmsg(struct kiocb *iocb, struct sock *sk, 137 struct msghdr *msg, size_t len); 138 extern void udp_flush_pending_frames(struct sock *sk); 139 140 extern int udp_rcv(struct sk_buff *skb); 141 extern int udp_ioctl(struct sock *sk, int cmd, unsigned long arg); 142 extern int udp_disconnect(struct sock *sk, int flags); 143 extern unsigned int udp_poll(struct file *file, struct socket *sock, 144 poll_table *wait); 145 extern int udp_lib_getsockopt(struct sock *sk, int level, int optname, 146 char __user *optval, int __user *optlen); 147 extern int udp_lib_setsockopt(struct sock *sk, int level, int optname, 148 char __user *optval, int optlen, 149 int (*push_pending_frames)(struct sock *)); 150 151 DECLARE_SNMP_STAT(struct udp_mib, udp_statistics); 152 DECLARE_SNMP_STAT(struct udp_mib, udp_stats_in6); 153 154 /* UDP-Lite does not have a standardized MIB yet, so we inherit from UDP */ 155 DECLARE_SNMP_STAT(struct udp_mib, udplite_statistics); 156 DECLARE_SNMP_STAT(struct udp_mib, udplite_stats_in6); 157 158 /* 159 * SNMP statistics for UDP and UDP-Lite 160 */ 161 #define UDP_INC_STATS_USER(field, is_udplite) do { \ 162 if (is_udplite) SNMP_INC_STATS_USER(udplite_statistics, field); \ 163 else SNMP_INC_STATS_USER(udp_statistics, field); } while(0) 164 #define UDP_INC_STATS_BH(field, is_udplite) do { \ 165 if (is_udplite) SNMP_INC_STATS_BH(udplite_statistics, field); \ 166 else SNMP_INC_STATS_BH(udp_statistics, field); } while(0) 167 168 #define UDP6_INC_STATS_BH(field, is_udplite) do { \ 169 if (is_udplite) SNMP_INC_STATS_BH(udplite_stats_in6, field); \ 170 else SNMP_INC_STATS_BH(udp_stats_in6, field); } while(0) 171 #define UDP6_INC_STATS_USER(field, is_udplite) do { \ 172 if (is_udplite) SNMP_INC_STATS_USER(udplite_stats_in6, field); \ 173 else SNMP_INC_STATS_USER(udp_stats_in6, field); } while(0) 174 175 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 176 #define UDPX_INC_STATS_BH(sk, field) \ 177 do { \ 178 if ((sk)->sk_family == AF_INET) \ 179 UDP_INC_STATS_BH(field, 0); \ 180 else \ 181 UDP6_INC_STATS_BH(field, 0); \ 182 } while (0); 183 #else 184 #define UDPX_INC_STATS_BH(sk, field) UDP_INC_STATS_BH(field, 0) 185 #endif 186 187 /* /proc */ 188 struct udp_seq_afinfo { 189 char *name; 190 sa_family_t family; 191 struct hlist_head *hashtable; 192 struct file_operations seq_fops; 193 struct seq_operations seq_ops; 194 }; 195 196 struct udp_iter_state { 197 struct seq_net_private p; 198 sa_family_t family; 199 struct hlist_head *hashtable; 200 int bucket; 201 }; 202 203 #ifdef CONFIG_PROC_FS 204 extern int udp_proc_register(struct net *net, struct udp_seq_afinfo *afinfo); 205 extern void udp_proc_unregister(struct net *net, struct udp_seq_afinfo *afinfo); 206 207 extern int udp4_proc_init(void); 208 extern void udp4_proc_exit(void); 209 #endif 210 211 extern void udp_init(void); 212 #endif /* _UDP_H */ 213