1 #ifndef _NFNETLINK_H 2 #define _NFNETLINK_H 3 #include <linux/types.h> 4 5 #ifndef __KERNEL__ 6 /* nfnetlink groups: Up to 32 maximum - backwards compatibility for userspace */ 7 #define NF_NETLINK_CONNTRACK_NEW 0x00000001 8 #define NF_NETLINK_CONNTRACK_UPDATE 0x00000002 9 #define NF_NETLINK_CONNTRACK_DESTROY 0x00000004 10 #define NF_NETLINK_CONNTRACK_EXP_NEW 0x00000008 11 #define NF_NETLINK_CONNTRACK_EXP_UPDATE 0x00000010 12 #define NF_NETLINK_CONNTRACK_EXP_DESTROY 0x00000020 13 #endif 14 15 enum nfnetlink_groups { 16 NFNLGRP_NONE, 17 #define NFNLGRP_NONE NFNLGRP_NONE 18 NFNLGRP_CONNTRACK_NEW, 19 #define NFNLGRP_CONNTRACK_NEW NFNLGRP_CONNTRACK_NEW 20 NFNLGRP_CONNTRACK_UPDATE, 21 #define NFNLGRP_CONNTRACK_UPDATE NFNLGRP_CONNTRACK_UPDATE 22 NFNLGRP_CONNTRACK_DESTROY, 23 #define NFNLGRP_CONNTRACK_DESTROY NFNLGRP_CONNTRACK_DESTROY 24 NFNLGRP_CONNTRACK_EXP_NEW, 25 #define NFNLGRP_CONNTRACK_EXP_NEW NFNLGRP_CONNTRACK_EXP_NEW 26 NFNLGRP_CONNTRACK_EXP_UPDATE, 27 #define NFNLGRP_CONNTRACK_EXP_UPDATE NFNLGRP_CONNTRACK_EXP_UPDATE 28 NFNLGRP_CONNTRACK_EXP_DESTROY, 29 #define NFNLGRP_CONNTRACK_EXP_DESTROY NFNLGRP_CONNTRACK_EXP_DESTROY 30 __NFNLGRP_MAX, 31 }; 32 #define NFNLGRP_MAX (__NFNLGRP_MAX - 1) 33 34 /* Generic structure for encapsulation optional netfilter information. 35 * It is reminiscent of sockaddr, but with sa_family replaced 36 * with attribute type. 37 * ! This should someday be put somewhere generic as now rtnetlink and 38 * ! nfnetlink use the same attributes methods. - J. Schulist. 39 */ 40 41 struct nfattr 42 { 43 u_int16_t nfa_len; 44 u_int16_t nfa_type; /* we use 15 bits for the type, and the highest 45 * bit to indicate whether the payload is nested */ 46 } __attribute__ ((packed)); 47 48 /* FIXME: Apart from NFNL_NFA_NESTED shamelessly copy and pasted from 49 * rtnetlink.h, it's time to put this in a generic file */ 50 51 #define NFNL_NFA_NEST 0x8000 52 #define NFA_TYPE(attr) ((attr)->nfa_type & 0x7fff) 53 54 #define NFA_ALIGNTO 4 55 #define NFA_ALIGN(len) (((len) + NFA_ALIGNTO - 1) & ~(NFA_ALIGNTO - 1)) 56 #define NFA_OK(nfa,len) ((len) > 0 && (nfa)->nfa_len >= sizeof(struct nfattr) \ 57 && (nfa)->nfa_len <= (len)) 58 #define NFA_NEXT(nfa,attrlen) ((attrlen) -= NFA_ALIGN((nfa)->nfa_len), \ 59 (struct nfattr *)(((char *)(nfa)) + NFA_ALIGN((nfa)->nfa_len))) 60 #define NFA_LENGTH(len) (NFA_ALIGN(sizeof(struct nfattr)) + (len)) 61 #define NFA_SPACE(len) NFA_ALIGN(NFA_LENGTH(len)) 62 #define NFA_DATA(nfa) ((void *)(((char *)(nfa)) + NFA_LENGTH(0))) 63 #define NFA_PAYLOAD(nfa) ((int)((nfa)->nfa_len) - NFA_LENGTH(0)) 64 #define NFA_NEST(skb, type) \ 65 ({ struct nfattr *__start = (struct nfattr *) (skb)->tail; \ 66 NFA_PUT(skb, (NFNL_NFA_NEST | type), 0, NULL); \ 67 __start; }) 68 #define NFA_NEST_END(skb, start) \ 69 ({ (start)->nfa_len = ((skb)->tail - (unsigned char *) (start)); \ 70 (skb)->len; }) 71 #define NFA_NEST_CANCEL(skb, start) \ 72 ({ if (start) \ 73 skb_trim(skb, (unsigned char *) (start) - (skb)->data); \ 74 -1; }) 75 76 /* General form of address family dependent message. 77 */ 78 struct nfgenmsg { 79 u_int8_t nfgen_family; /* AF_xxx */ 80 u_int8_t version; /* nfnetlink version */ 81 u_int16_t res_id; /* resource id */ 82 } __attribute__ ((packed)); 83 84 #define NFNETLINK_V0 0 85 86 #define NFM_NFA(n) ((struct nfattr *)(((char *)(n)) \ 87 + NLMSG_ALIGN(sizeof(struct nfgenmsg)))) 88 #define NFM_PAYLOAD(n) NLMSG_PAYLOAD(n, sizeof(struct nfgenmsg)) 89 90 /* netfilter netlink message types are split in two pieces: 91 * 8 bit subsystem, 8bit operation. 92 */ 93 94 #define NFNL_SUBSYS_ID(x) ((x & 0xff00) >> 8) 95 #define NFNL_MSG_TYPE(x) (x & 0x00ff) 96 97 /* No enum here, otherwise __stringify() trick of MODULE_ALIAS_NFNL_SUBSYS() 98 * won't work anymore */ 99 #define NFNL_SUBSYS_NONE 0 100 #define NFNL_SUBSYS_CTNETLINK 1 101 #define NFNL_SUBSYS_CTNETLINK_EXP 2 102 #define NFNL_SUBSYS_QUEUE 3 103 #define NFNL_SUBSYS_ULOG 4 104 #define NFNL_SUBSYS_COUNT 5 105 106 #ifdef __KERNEL__ 107 108 #include <linux/netlink.h> 109 #include <linux/capability.h> 110 111 struct nfnl_callback 112 { 113 int (*call)(struct sock *nl, struct sk_buff *skb, 114 struct nlmsghdr *nlh, struct nfattr *cda[], int *errp); 115 u_int16_t attr_count; /* number of nfattr's */ 116 }; 117 118 struct nfnetlink_subsystem 119 { 120 const char *name; 121 __u8 subsys_id; /* nfnetlink subsystem ID */ 122 __u8 cb_count; /* number of callbacks */ 123 struct nfnl_callback *cb; /* callback for individual types */ 124 }; 125 126 extern void __nfa_fill(struct sk_buff *skb, int attrtype, 127 int attrlen, const void *data); 128 #define NFA_PUT(skb, attrtype, attrlen, data) \ 129 ({ if (skb_tailroom(skb) < (int)NFA_SPACE(attrlen)) goto nfattr_failure; \ 130 __nfa_fill(skb, attrtype, attrlen, data); }) 131 132 extern struct semaphore nfnl_sem; 133 134 #define nfnl_shlock() down(&nfnl_sem) 135 #define nfnl_shlock_nowait() down_trylock(&nfnl_sem) 136 137 #define nfnl_shunlock() do { up(&nfnl_sem); \ 138 if(nfnl && nfnl->sk_receive_queue.qlen) \ 139 nfnl->sk_data_ready(nfnl, 0); \ 140 } while(0) 141 142 extern void nfnl_lock(void); 143 extern void nfnl_unlock(void); 144 145 extern int nfnetlink_subsys_register(struct nfnetlink_subsystem *n); 146 extern int nfnetlink_subsys_unregister(struct nfnetlink_subsystem *n); 147 148 extern void nfattr_parse(struct nfattr *tb[], int maxattr, 149 struct nfattr *nfa, int len); 150 151 #define nfattr_parse_nested(tb, max, nfa) \ 152 nfattr_parse((tb), (max), NFA_DATA((nfa)), NFA_PAYLOAD((nfa))) 153 154 #define nfattr_bad_size(tb, max, cta_min) \ 155 ({ int __i, __res = 0; \ 156 for (__i=0; __i<max; __i++) { \ 157 if (!cta_min[__i]) \ 158 continue; \ 159 if (tb[__i] && NFA_PAYLOAD(tb[__i]) < cta_min[__i]){ \ 160 __res = 1; \ 161 break; \ 162 } \ 163 } \ 164 __res; \ 165 }) 166 167 extern int nfnetlink_has_listeners(unsigned int group); 168 extern int nfnetlink_send(struct sk_buff *skb, u32 pid, unsigned group, 169 int echo); 170 extern int nfnetlink_unicast(struct sk_buff *skb, u_int32_t pid, int flags); 171 172 #define MODULE_ALIAS_NFNL_SUBSYS(subsys) \ 173 MODULE_ALIAS("nfnetlink-subsys-" __stringify(subsys)) 174 175 #endif /* __KERNEL__ */ 176 #endif /* _NFNETLINK_H */ 177