/* * INET An implementation of the TCP/IP protocol suite for the LINUX * operating system. INET is implemented using the BSD Socket * interface as the means of communication with the user level. * * Definitions for the IP module. * * Version: @(#)ip.h 1.0.2 05/07/93 * * Authors: Ross Biro * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> * Alan Cox, <gw4pts@gw4pts.ampr.org> * * Changes: * Mike McLagan : Routing by source * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. */ #ifndef _IP_H #define _IP_H #include <linux/types.h> #include <linux/ip.h> #include <linux/in.h> #include <linux/skbuff.h> #include <net/inet_sock.h> #include <net/snmp.h> #include <net/flow.h> struct sock; struct inet_skb_parm { struct ip_options opt; /* Compiled IP options */ unsigned char flags; #define IPSKB_FORWARDED 1 #define IPSKB_XFRM_TUNNEL_SIZE 2 #define IPSKB_XFRM_TRANSFORMED 4 #define IPSKB_FRAG_COMPLETE 8 #define IPSKB_REROUTED 16 u16 frag_max_size; }; static inline unsigned int ip_hdrlen(const struct sk_buff *skb) { return ip_hdr(skb)->ihl * 4; } struct ipcm_cookie { __be32 addr; int oif; struct ip_options_rcu *opt; __u8 tx_flags; }; #define IPCB(skb) ((struct inet_skb_parm*)((skb)->cb)) struct ip_ra_chain { struct ip_ra_chain __rcu *next; struct sock *sk; union { void (*destructor)(struct sock *); struct sock *saved_sk; }; struct rcu_head rcu; }; extern struct ip_ra_chain __rcu *ip_ra_chain; /* IP flags. */ #define IP_CE 0x8000 /* Flag: "Congestion" */ #define IP_DF 0x4000 /* Flag: "Don't Fragment" */ #define IP_MF 0x2000 /* Flag: "More Fragments" */ #define IP_OFFSET 0x1FFF /* "Fragment Offset" part */ #define IP_FRAG_TIME (30 * HZ) /* fragment lifetime */ struct msghdr; struct net_device; struct packet_type; struct rtable; struct sockaddr; extern int igmp_mc_proc_init(void); /* * Functions provided by ip.c */ extern int ip_build_and_send_pkt(struct sk_buff *skb, struct sock *sk, __be32 saddr, __be32 daddr, struct ip_options_rcu *opt); extern int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev); extern int ip_local_deliver(struct sk_buff *skb); extern int ip_mr_input(struct sk_buff *skb); extern int ip_output(struct sk_buff *skb); extern int ip_mc_output(struct sk_buff *skb); extern int ip_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *)); extern int ip_do_nat(struct sk_buff *skb); extern void ip_send_check(struct iphdr *ip); extern int __ip_local_out(struct sk_buff *skb); extern int ip_local_out(struct sk_buff *skb); extern int ip_queue_xmit(struct sk_buff *skb, struct flowi *fl); extern void ip_init(void); extern int ip_append_data(struct sock *sk, struct flowi4 *fl4, int getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb), void *from, int len, int protolen, struct ipcm_cookie *ipc, struct rtable **rt, unsigned int flags); extern int ip_generic_getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb); extern ssize_t ip_append_page(struct sock *sk, struct flowi4 *fl4, struct page *page, int offset, size_t size, int flags); extern struct sk_buff *__ip_make_skb(struct sock *sk, struct flowi4 *fl4, struct sk_buff_head *queue, struct inet_cork *cork); extern int ip_send_skb(struct net *net, struct sk_buff *skb); extern int ip_push_pending_frames(struct sock *sk, struct flowi4 *fl4); extern void ip_flush_pending_frames(struct sock *sk); extern struct sk_buff *ip_make_skb(struct sock *sk, struct flowi4 *fl4, int getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb), void *from, int length, int transhdrlen, struct ipcm_cookie *ipc, struct rtable **rtp, unsigned int flags); static inline struct sk_buff *ip_finish_skb(struct sock *sk, struct flowi4 *fl4) { return __ip_make_skb(sk, fl4, &sk->sk_write_queue, &inet_sk(sk)->cork.base); } /* datagram.c */ extern int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len); struct ip_reply_arg { struct kvec iov[1]; int flags; __wsum csum; int csumoffset; /* u16 offset of csum in iov[0].iov_base */ /* -1 if not needed */ int bound_dev_if; u8 tos; }; #define IP_REPLY_ARG_NOSRCCHECK 1 static inline __u8 ip_reply_arg_flowi_flags(const struct ip_reply_arg *arg) { return (arg->flags & IP_REPLY_ARG_NOSRCCHECK) ? FLOWI_FLAG_ANYSRC : 0; } void ip_send_unicast_reply(struct net *net, struct sk_buff *skb, __be32 daddr, __be32 saddr, const struct ip_reply_arg *arg, unsigned int len); struct ipv4_config { int log_martians; int no_pmtu_disc; }; extern struct ipv4_config ipv4_config; #define IP_INC_STATS(net, field) SNMP_INC_STATS64((net)->mib.ip_statistics, field) #define IP_INC_STATS_BH(net, field) SNMP_INC_STATS64_BH((net)->mib.ip_statistics, field) #define IP_ADD_STATS(net, field, val) SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val) #define IP_ADD_STATS_BH(net, field, val) SNMP_ADD_STATS64_BH((net)->mib.ip_statistics, field, val) #define IP_UPD_PO_STATS(net, field, val) SNMP_UPD_PO_STATS64((net)->mib.ip_statistics, field, val) #define IP_UPD_PO_STATS_BH(net, field, val) SNMP_UPD_PO_STATS64_BH((net)->mib.ip_statistics, field, val) #define NET_INC_STATS(net, field) SNMP_INC_STATS((net)->mib.net_statistics, field) #define NET_INC_STATS_BH(net, field) SNMP_INC_STATS_BH((net)->mib.net_statistics, field) #define NET_INC_STATS_USER(net, field) SNMP_INC_STATS_USER((net)->mib.net_statistics, field) #define NET_ADD_STATS_BH(net, field, adnd) SNMP_ADD_STATS_BH((net)->mib.net_statistics, field, adnd) #define NET_ADD_STATS_USER(net, field, adnd) SNMP_ADD_STATS_USER((net)->mib.net_statistics, field, adnd) extern unsigned long snmp_fold_field(void __percpu *mib[], int offt); #if BITS_PER_LONG==32 extern u64 snmp_fold_field64(void __percpu *mib[], int offt, size_t sync_off); #else static inline u64 snmp_fold_field64(void __percpu *mib[], int offt, size_t syncp_off) { return snmp_fold_field(mib, offt); } #endif extern int snmp_mib_init(void __percpu *ptr[2], size_t mibsize, size_t align); extern void snmp_mib_free(void __percpu *ptr[2]); extern struct local_ports { seqlock_t lock; int range[2]; } sysctl_local_ports; extern void inet_get_local_port_range(int *low, int *high); extern unsigned long *sysctl_local_reserved_ports; static inline int inet_is_reserved_local_port(int port) { return test_bit(port, sysctl_local_reserved_ports); } extern int sysctl_ip_nonlocal_bind; /* From inetpeer.c */ extern int inet_peer_threshold; extern int inet_peer_minttl; extern int inet_peer_maxttl; /* From ip_input.c */ extern int sysctl_ip_early_demux; /* From ip_output.c */ extern int sysctl_ip_dynaddr; extern void ipfrag_init(void); extern void ip_static_sysctl_init(void); static inline bool ip_is_fragment(const struct iphdr *iph) { return (iph->frag_off & htons(IP_MF | IP_OFFSET)) != 0; } #ifdef CONFIG_INET #include <net/dst.h> /* The function in 2.2 was invalid, producing wrong result for * check=0xFEFF. It was noticed by Arthur Skawina _year_ ago. --ANK(000625) */ static inline int ip_decrease_ttl(struct iphdr *iph) { u32 check = (__force u32)iph->check; check += (__force u32)htons(0x0100); iph->check = (__force __sum16)(check + (check>=0xFFFF)); return --iph->ttl; } static inline int ip_dont_fragment(struct sock *sk, struct dst_entry *dst) { return inet_sk(sk)->pmtudisc == IP_PMTUDISC_DO || (inet_sk(sk)->pmtudisc == IP_PMTUDISC_WANT && !(dst_metric_locked(dst, RTAX_MTU))); } extern void __ip_select_ident(struct iphdr *iph, struct dst_entry *dst, int more); static inline void ip_select_ident(struct iphdr *iph, struct dst_entry *dst, struct sock *sk) { if (iph->frag_off & htons(IP_DF)) { /* This is only to work around buggy Windows95/2000 * VJ compression implementations. If the ID field * does not change, they drop every other packet in * a TCP stream using header compression. */ iph->id = (sk && inet_sk(sk)->inet_daddr) ? htons(inet_sk(sk)->inet_id++) : 0; } else __ip_select_ident(iph, dst, 0); } static inline void ip_select_ident_more(struct iphdr *iph, struct dst_entry *dst, struct sock *sk, int more) { if (iph->frag_off & htons(IP_DF)) { if (sk && inet_sk(sk)->inet_daddr) { iph->id = htons(inet_sk(sk)->inet_id); inet_sk(sk)->inet_id += 1 + more; } else iph->id = 0; } else __ip_select_ident(iph, dst, more); } /* * Map a multicast IP onto multicast MAC for type ethernet. */ static inline void ip_eth_mc_map(__be32 naddr, char *buf) { __u32 addr=ntohl(naddr); buf[0]=0x01; buf[1]=0x00; buf[2]=0x5e; buf[5]=addr&0xFF; addr>>=8; buf[4]=addr&0xFF; addr>>=8; buf[3]=addr&0x7F; } /* * Map a multicast IP onto multicast MAC for type IP-over-InfiniBand. * Leave P_Key as 0 to be filled in by driver. */ static inline void ip_ib_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf) { __u32 addr; unsigned char scope = broadcast[5] & 0xF; buf[0] = 0; /* Reserved */ buf[1] = 0xff; /* Multicast QPN */ buf[2] = 0xff; buf[3] = 0xff; addr = ntohl(naddr); buf[4] = 0xff; buf[5] = 0x10 | scope; /* scope from broadcast address */ buf[6] = 0x40; /* IPv4 signature */ buf[7] = 0x1b; buf[8] = broadcast[8]; /* P_Key */ buf[9] = broadcast[9]; buf[10] = 0; buf[11] = 0; buf[12] = 0; buf[13] = 0; buf[14] = 0; buf[15] = 0; buf[19] = addr & 0xff; addr >>= 8; buf[18] = addr & 0xff; addr >>= 8; buf[17] = addr & 0xff; addr >>= 8; buf[16] = addr & 0x0f; } static inline void ip_ipgre_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf) { if ((broadcast[0] | broadcast[1] | broadcast[2] | broadcast[3]) != 0) memcpy(buf, broadcast, 4); else memcpy(buf, &naddr, sizeof(naddr)); } #if IS_ENABLED(CONFIG_IPV6) #include <linux/ipv6.h> #endif static __inline__ void inet_reset_saddr(struct sock *sk) { inet_sk(sk)->inet_rcv_saddr = inet_sk(sk)->inet_saddr = 0; #if IS_ENABLED(CONFIG_IPV6) if (sk->sk_family == PF_INET6) { struct ipv6_pinfo *np = inet6_sk(sk); memset(&np->saddr, 0, sizeof(np->saddr)); memset(&np->rcv_saddr, 0, sizeof(np->rcv_saddr)); } #endif } #endif static inline int sk_mc_loop(struct sock *sk) { if (!sk) return 1; switch (sk->sk_family) { case AF_INET: return inet_sk(sk)->mc_loop; #if IS_ENABLED(CONFIG_IPV6) case AF_INET6: return inet6_sk(sk)->mc_loop; #endif } WARN_ON(1); return 1; } extern bool ip_call_ra_chain(struct sk_buff *skb); /* * Functions provided by ip_fragment.c */ enum ip_defrag_users { IP_DEFRAG_LOCAL_DELIVER, IP_DEFRAG_CALL_RA_CHAIN, IP_DEFRAG_CONNTRACK_IN, __IP_DEFRAG_CONNTRACK_IN_END = IP_DEFRAG_CONNTRACK_IN + USHRT_MAX, IP_DEFRAG_CONNTRACK_OUT, __IP_DEFRAG_CONNTRACK_OUT_END = IP_DEFRAG_CONNTRACK_OUT + USHRT_MAX, IP_DEFRAG_CONNTRACK_BRIDGE_IN, __IP_DEFRAG_CONNTRACK_BRIDGE_IN = IP_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX, IP_DEFRAG_VS_IN, IP_DEFRAG_VS_OUT, IP_DEFRAG_VS_FWD, IP_DEFRAG_AF_PACKET, IP_DEFRAG_MACVLAN, }; int ip_defrag(struct sk_buff *skb, u32 user); #ifdef CONFIG_INET struct sk_buff *ip_check_defrag(struct sk_buff *skb, u32 user); #else static inline struct sk_buff *ip_check_defrag(struct sk_buff *skb, u32 user) { return skb; } #endif int ip_frag_mem(struct net *net); int ip_frag_nqueues(struct net *net); /* * Functions provided by ip_forward.c */ extern int ip_forward(struct sk_buff *skb); /* * Functions provided by ip_options.c */ extern void ip_options_build(struct sk_buff *skb, struct ip_options *opt, __be32 daddr, struct rtable *rt, int is_frag); extern int ip_options_echo(struct ip_options *dopt, struct sk_buff *skb); extern void ip_options_fragment(struct sk_buff *skb); extern int ip_options_compile(struct net *net, struct ip_options *opt, struct sk_buff *skb); extern int ip_options_get(struct net *net, struct ip_options_rcu **optp, unsigned char *data, int optlen); extern int ip_options_get_from_user(struct net *net, struct ip_options_rcu **optp, unsigned char __user *data, int optlen); extern void ip_options_undo(struct ip_options * opt); extern void ip_forward_options(struct sk_buff *skb); extern int ip_options_rcv_srr(struct sk_buff *skb); /* * Functions provided by ip_sockglue.c */ extern void ipv4_pktinfo_prepare(struct sk_buff *skb); extern void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb); extern int ip_cmsg_send(struct net *net, struct msghdr *msg, struct ipcm_cookie *ipc); extern int ip_setsockopt(struct sock *sk, int level, int optname, char __user *optval, unsigned int optlen); extern int ip_getsockopt(struct sock *sk, int level, int optname, char __user *optval, int __user *optlen); extern int compat_ip_setsockopt(struct sock *sk, int level, int optname, char __user *optval, unsigned int optlen); extern int compat_ip_getsockopt(struct sock *sk, int level, int optname, char __user *optval, int __user *optlen); extern int ip_ra_control(struct sock *sk, unsigned char on, void (*destructor)(struct sock *)); extern int ip_recv_error(struct sock *sk, struct msghdr *msg, int len); extern void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port, u32 info, u8 *payload); extern void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 dport, u32 info); #ifdef CONFIG_PROC_FS extern int ip_misc_proc_init(void); #endif #endif /* _IP_H */