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 struct udp_hslot { 54 struct hlist_nulls_head head; 55 spinlock_t lock; 56 } __attribute__((aligned(2 * sizeof(long)))); 57 struct udp_table { 58 struct udp_hslot hash[UDP_HTABLE_SIZE]; 59 }; 60 extern struct udp_table udp_table; 61 extern void udp_table_init(struct udp_table *); 62 63 64 /* Note: this must match 'valbool' in sock_setsockopt */ 65 #define UDP_CSUM_NOXMIT 1 66 67 /* Used by SunRPC/xprt layer. */ 68 #define UDP_CSUM_NORCV 2 69 70 /* Default, as per the RFC, is to always do csums. */ 71 #define UDP_CSUM_DEFAULT 0 72 73 extern struct proto udp_prot; 74 75 extern atomic_t udp_memory_allocated; 76 77 /* sysctl variables for udp */ 78 extern int sysctl_udp_mem[3]; 79 extern int sysctl_udp_rmem_min; 80 extern int sysctl_udp_wmem_min; 81 82 struct sk_buff; 83 84 /* 85 * Generic checksumming routines for UDP(-Lite) v4 and v6 86 */ 87 static inline __sum16 __udp_lib_checksum_complete(struct sk_buff *skb) 88 { 89 return __skb_checksum_complete_head(skb, UDP_SKB_CB(skb)->cscov); 90 } 91 92 static inline int udp_lib_checksum_complete(struct sk_buff *skb) 93 { 94 return !skb_csum_unnecessary(skb) && 95 __udp_lib_checksum_complete(skb); 96 } 97 98 /** 99 * udp_csum_outgoing - compute UDPv4/v6 checksum over fragments 100 * @sk: socket we are writing to 101 * @skb: sk_buff containing the filled-in UDP header 102 * (checksum field must be zeroed out) 103 */ 104 static inline __wsum udp_csum_outgoing(struct sock *sk, struct sk_buff *skb) 105 { 106 __wsum csum = csum_partial(skb_transport_header(skb), 107 sizeof(struct udphdr), 0); 108 skb_queue_walk(&sk->sk_write_queue, skb) { 109 csum = csum_add(csum, skb->csum); 110 } 111 return csum; 112 } 113 114 /* hash routines shared between UDPv4/6 and UDP-Litev4/6 */ 115 static inline void udp_lib_hash(struct sock *sk) 116 { 117 BUG(); 118 } 119 120 extern void udp_lib_unhash(struct sock *sk); 121 122 static inline void udp_lib_close(struct sock *sk, long timeout) 123 { 124 sk_common_release(sk); 125 } 126 127 extern int ipv4_rcv_saddr_equal(const struct sock *sk1, 128 const struct sock *sk2); 129 extern int udp_lib_get_port(struct sock *sk, unsigned short snum, 130 int (*)(const struct sock*,const struct sock*)); 131 132 /* net/ipv4/udp.c */ 133 extern int udp_get_port(struct sock *sk, unsigned short snum, 134 int (*saddr_cmp)(const struct sock *, const struct sock *)); 135 extern void udp_err(struct sk_buff *, u32); 136 137 extern int udp_sendmsg(struct kiocb *iocb, struct sock *sk, 138 struct msghdr *msg, size_t len); 139 extern void udp_flush_pending_frames(struct sock *sk); 140 141 extern int udp_rcv(struct sk_buff *skb); 142 extern int udp_ioctl(struct sock *sk, int cmd, unsigned long arg); 143 extern int udp_disconnect(struct sock *sk, int flags); 144 extern unsigned int udp_poll(struct file *file, struct socket *sock, 145 poll_table *wait); 146 extern int udp_lib_getsockopt(struct sock *sk, int level, int optname, 147 char __user *optval, int __user *optlen); 148 extern int udp_lib_setsockopt(struct sock *sk, int level, int optname, 149 char __user *optval, int optlen, 150 int (*push_pending_frames)(struct sock *)); 151 152 extern struct sock *udp4_lib_lookup(struct net *net, __be32 saddr, __be16 sport, 153 __be32 daddr, __be16 dport, 154 int dif); 155 156 /* 157 * SNMP statistics for UDP and UDP-Lite 158 */ 159 #define UDP_INC_STATS_USER(net, field, is_udplite) do { \ 160 if (is_udplite) SNMP_INC_STATS_USER((net)->mib.udplite_statistics, field); \ 161 else SNMP_INC_STATS_USER((net)->mib.udp_statistics, field); } while(0) 162 #define UDP_INC_STATS_BH(net, field, is_udplite) do { \ 163 if (is_udplite) SNMP_INC_STATS_BH((net)->mib.udplite_statistics, field); \ 164 else SNMP_INC_STATS_BH((net)->mib.udp_statistics, field); } while(0) 165 166 #define UDP6_INC_STATS_BH(net, field, is_udplite) do { \ 167 if (is_udplite) SNMP_INC_STATS_BH((net)->mib.udplite_stats_in6, field);\ 168 else SNMP_INC_STATS_BH((net)->mib.udp_stats_in6, field); \ 169 } while(0) 170 #define UDP6_INC_STATS_USER(net, field, __lite) do { \ 171 if (__lite) SNMP_INC_STATS_USER((net)->mib.udplite_stats_in6, field); \ 172 else SNMP_INC_STATS_USER((net)->mib.udp_stats_in6, field); \ 173 } 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(sock_net(sk), field, 0); \ 180 else \ 181 UDP6_INC_STATS_BH(sock_net(sk), field, 0); \ 182 } while (0); 183 #else 184 #define UDPX_INC_STATS_BH(sk, field) UDP_INC_STATS_BH(sock_net(sk), field, 0) 185 #endif 186 187 /* /proc */ 188 struct udp_seq_afinfo { 189 char *name; 190 sa_family_t family; 191 struct udp_table *udp_table; 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 int bucket; 200 struct udp_table *udp_table; 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