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-rw-r--r--include/net/ip.h806
1 files changed, 806 insertions, 0 deletions
diff --git a/include/net/ip.h b/include/net/ip.h
new file mode 100644
index 000000000..c83c09c65
--- /dev/null
+++ b/include/net/ip.h
@@ -0,0 +1,806 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * 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
+ */
+#ifndef _IP_H
+#define _IP_H
+
+#include <linux/types.h>
+#include <linux/ip.h>
+#include <linux/in.h>
+#include <linux/skbuff.h>
+#include <linux/jhash.h>
+#include <linux/sockptr.h>
+#include <linux/static_key.h>
+
+#include <net/inet_sock.h>
+#include <net/route.h>
+#include <net/snmp.h>
+#include <net/flow.h>
+#include <net/flow_dissector.h>
+#include <net/netns/hash.h>
+#include <net/lwtunnel.h>
+
+#define IPV4_MAX_PMTU 65535U /* RFC 2675, Section 5.1 */
+#define IPV4_MIN_MTU 68 /* RFC 791 */
+
+extern unsigned int sysctl_fib_sync_mem;
+extern unsigned int sysctl_fib_sync_mem_min;
+extern unsigned int sysctl_fib_sync_mem_max;
+
+struct sock;
+
+struct inet_skb_parm {
+ int iif;
+ struct ip_options opt; /* Compiled IP options */
+ u16 flags;
+
+#define IPSKB_FORWARDED BIT(0)
+#define IPSKB_XFRM_TUNNEL_SIZE BIT(1)
+#define IPSKB_XFRM_TRANSFORMED BIT(2)
+#define IPSKB_FRAG_COMPLETE BIT(3)
+#define IPSKB_REROUTED BIT(4)
+#define IPSKB_DOREDIRECT BIT(5)
+#define IPSKB_FRAG_PMTU BIT(6)
+#define IPSKB_L3SLAVE BIT(7)
+#define IPSKB_NOPOLICY BIT(8)
+#define IPSKB_MULTIPATH BIT(9)
+
+ u16 frag_max_size;
+};
+
+static inline bool ipv4_l3mdev_skb(u16 flags)
+{
+ return !!(flags & IPSKB_L3SLAVE);
+}
+
+static inline unsigned int ip_hdrlen(const struct sk_buff *skb)
+{
+ return ip_hdr(skb)->ihl * 4;
+}
+
+struct ipcm_cookie {
+ struct sockcm_cookie sockc;
+ __be32 addr;
+ int oif;
+ struct ip_options_rcu *opt;
+ __u8 protocol;
+ __u8 ttl;
+ __s16 tos;
+ char priority;
+ __u16 gso_size;
+};
+
+static inline void ipcm_init(struct ipcm_cookie *ipcm)
+{
+ *ipcm = (struct ipcm_cookie) { .tos = -1 };
+}
+
+static inline void ipcm_init_sk(struct ipcm_cookie *ipcm,
+ const struct inet_sock *inet)
+{
+ ipcm_init(ipcm);
+
+ ipcm->sockc.mark = READ_ONCE(inet->sk.sk_mark);
+ ipcm->sockc.tsflags = READ_ONCE(inet->sk.sk_tsflags);
+ ipcm->oif = READ_ONCE(inet->sk.sk_bound_dev_if);
+ ipcm->addr = inet->inet_saddr;
+ ipcm->protocol = inet->inet_num;
+}
+
+#define IPCB(skb) ((struct inet_skb_parm*)((skb)->cb))
+#define PKTINFO_SKB_CB(skb) ((struct in_pktinfo *)((skb)->cb))
+
+/* return enslaved device index if relevant */
+static inline int inet_sdif(const struct sk_buff *skb)
+{
+#if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV)
+ if (skb && ipv4_l3mdev_skb(IPCB(skb)->flags))
+ return IPCB(skb)->iif;
+#endif
+ return 0;
+}
+
+/* Special input handler for packets caught by router alert option.
+ They are selected only by protocol field, and then processed likely
+ local ones; but only if someone wants them! Otherwise, router
+ not running rsvpd will kill RSVP.
+
+ It is user level problem, what it will make with them.
+ I have no idea, how it will masquearde or NAT them (it is joke, joke :-)),
+ but receiver should be enough clever f.e. to forward mtrace requests,
+ sent to multicast group to reach destination designated router.
+ */
+
+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;
+};
+
+/* 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;
+
+int igmp_mc_init(void);
+
+/*
+ * Functions provided by ip.c
+ */
+
+int ip_build_and_send_pkt(struct sk_buff *skb, const struct sock *sk,
+ __be32 saddr, __be32 daddr,
+ struct ip_options_rcu *opt, u8 tos);
+int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt,
+ struct net_device *orig_dev);
+void ip_list_rcv(struct list_head *head, struct packet_type *pt,
+ struct net_device *orig_dev);
+int ip_local_deliver(struct sk_buff *skb);
+void ip_protocol_deliver_rcu(struct net *net, struct sk_buff *skb, int proto);
+int ip_mr_input(struct sk_buff *skb);
+int ip_output(struct net *net, struct sock *sk, struct sk_buff *skb);
+int ip_mc_output(struct net *net, struct sock *sk, struct sk_buff *skb);
+int ip_do_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
+ int (*output)(struct net *, struct sock *, struct sk_buff *));
+
+struct ip_fraglist_iter {
+ struct sk_buff *frag;
+ struct iphdr *iph;
+ int offset;
+ unsigned int hlen;
+};
+
+void ip_fraglist_init(struct sk_buff *skb, struct iphdr *iph,
+ unsigned int hlen, struct ip_fraglist_iter *iter);
+void ip_fraglist_prepare(struct sk_buff *skb, struct ip_fraglist_iter *iter);
+
+static inline struct sk_buff *ip_fraglist_next(struct ip_fraglist_iter *iter)
+{
+ struct sk_buff *skb = iter->frag;
+
+ iter->frag = skb->next;
+ skb_mark_not_on_list(skb);
+
+ return skb;
+}
+
+struct ip_frag_state {
+ bool DF;
+ unsigned int hlen;
+ unsigned int ll_rs;
+ unsigned int mtu;
+ unsigned int left;
+ int offset;
+ int ptr;
+ __be16 not_last_frag;
+};
+
+void ip_frag_init(struct sk_buff *skb, unsigned int hlen, unsigned int ll_rs,
+ unsigned int mtu, bool DF, struct ip_frag_state *state);
+struct sk_buff *ip_frag_next(struct sk_buff *skb,
+ struct ip_frag_state *state);
+
+void ip_send_check(struct iphdr *ip);
+int __ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
+int ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
+
+int __ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl,
+ __u8 tos);
+void ip_init(void);
+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);
+int ip_generic_getfrag(void *from, char *to, int offset, int len, int odd,
+ struct sk_buff *skb);
+ssize_t ip_append_page(struct sock *sk, struct flowi4 *fl4, struct page *page,
+ int offset, size_t size, int flags);
+struct sk_buff *__ip_make_skb(struct sock *sk, struct flowi4 *fl4,
+ struct sk_buff_head *queue,
+ struct inet_cork *cork);
+int ip_send_skb(struct net *net, struct sk_buff *skb);
+int ip_push_pending_frames(struct sock *sk, struct flowi4 *fl4);
+void ip_flush_pending_frames(struct sock *sk);
+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,
+ struct inet_cork *cork, unsigned int flags);
+
+int ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl);
+
+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);
+}
+
+static inline __u8 get_rttos(struct ipcm_cookie* ipc, struct inet_sock *inet)
+{
+ return (ipc->tos != -1) ? RT_TOS(ipc->tos) : RT_TOS(inet->tos);
+}
+
+static inline __u8 get_rtconn_flags(struct ipcm_cookie* ipc, struct sock* sk)
+{
+ return (ipc->tos != -1) ? RT_CONN_FLAGS_TOS(sk, ipc->tos) : RT_CONN_FLAGS(sk);
+}
+
+/* datagram.c */
+int __ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len);
+int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len);
+
+void ip4_datagram_release_cb(struct sock *sk);
+
+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;
+ kuid_t uid;
+};
+
+#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 sock *sk, struct sk_buff *skb,
+ const struct ip_options *sopt,
+ __be32 daddr, __be32 saddr,
+ const struct ip_reply_arg *arg,
+ unsigned int len, u64 transmit_time, u32 txhash);
+
+#define IP_INC_STATS(net, field) SNMP_INC_STATS64((net)->mib.ip_statistics, field)
+#define __IP_INC_STATS(net, field) __SNMP_INC_STATS64((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(net, field, val) __SNMP_ADD_STATS64((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(net, field, val) __SNMP_UPD_PO_STATS64((net)->mib.ip_statistics, field, val)
+#define NET_INC_STATS(net, field) SNMP_INC_STATS((net)->mib.net_statistics, field)
+#define __NET_INC_STATS(net, field) __SNMP_INC_STATS((net)->mib.net_statistics, field)
+#define NET_ADD_STATS(net, field, adnd) SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd)
+#define __NET_ADD_STATS(net, field, adnd) __SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd)
+
+static inline u64 snmp_get_cpu_field(void __percpu *mib, int cpu, int offt)
+{
+ return *(((unsigned long *)per_cpu_ptr(mib, cpu)) + offt);
+}
+
+unsigned long snmp_fold_field(void __percpu *mib, int offt);
+#if BITS_PER_LONG==32
+u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct,
+ size_t syncp_offset);
+u64 snmp_fold_field64(void __percpu *mib, int offt, size_t sync_off);
+#else
+static inline u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct,
+ size_t syncp_offset)
+{
+ return snmp_get_cpu_field(mib, cpu, offct);
+
+}
+
+static inline u64 snmp_fold_field64(void __percpu *mib, int offt, size_t syncp_off)
+{
+ return snmp_fold_field(mib, offt);
+}
+#endif
+
+#define snmp_get_cpu_field64_batch(buff64, stats_list, mib_statistic, offset) \
+{ \
+ int i, c; \
+ for_each_possible_cpu(c) { \
+ for (i = 0; stats_list[i].name; i++) \
+ buff64[i] += snmp_get_cpu_field64( \
+ mib_statistic, \
+ c, stats_list[i].entry, \
+ offset); \
+ } \
+}
+
+#define snmp_get_cpu_field_batch(buff, stats_list, mib_statistic) \
+{ \
+ int i, c; \
+ for_each_possible_cpu(c) { \
+ for (i = 0; stats_list[i].name; i++) \
+ buff[i] += snmp_get_cpu_field( \
+ mib_statistic, \
+ c, stats_list[i].entry); \
+ } \
+}
+
+void inet_get_local_port_range(const struct net *net, int *low, int *high);
+void inet_sk_get_local_port_range(const struct sock *sk, int *low, int *high);
+
+#ifdef CONFIG_SYSCTL
+static inline bool inet_is_local_reserved_port(struct net *net, unsigned short port)
+{
+ if (!net->ipv4.sysctl_local_reserved_ports)
+ return false;
+ return test_bit(port, net->ipv4.sysctl_local_reserved_ports);
+}
+
+static inline bool sysctl_dev_name_is_allowed(const char *name)
+{
+ return strcmp(name, "default") != 0 && strcmp(name, "all") != 0;
+}
+
+static inline bool inet_port_requires_bind_service(struct net *net, unsigned short port)
+{
+ return port < READ_ONCE(net->ipv4.sysctl_ip_prot_sock);
+}
+
+#else
+static inline bool inet_is_local_reserved_port(struct net *net, unsigned short port)
+{
+ return false;
+}
+
+static inline bool inet_port_requires_bind_service(struct net *net, unsigned short port)
+{
+ return port < PROT_SOCK;
+}
+#endif
+
+__be32 inet_current_timestamp(void);
+
+/* From inetpeer.c */
+extern int inet_peer_threshold;
+extern int inet_peer_minttl;
+extern int inet_peer_maxttl;
+
+void ipfrag_init(void);
+
+void ip_static_sysctl_init(void);
+
+#define IP4_REPLY_MARK(net, mark) \
+ (READ_ONCE((net)->ipv4.sysctl_fwmark_reflect) ? (mark) : 0)
+
+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_mtu_locked(const struct dst_entry *dst)
+{
+ const struct rtable *rt = (const struct rtable *)dst;
+
+ return rt->rt_mtu_locked || dst_metric_locked(dst, RTAX_MTU);
+}
+
+static inline
+int ip_dont_fragment(const struct sock *sk, const struct dst_entry *dst)
+{
+ u8 pmtudisc = READ_ONCE(inet_sk(sk)->pmtudisc);
+
+ return pmtudisc == IP_PMTUDISC_DO ||
+ (pmtudisc == IP_PMTUDISC_WANT &&
+ !ip_mtu_locked(dst));
+}
+
+static inline bool ip_sk_accept_pmtu(const struct sock *sk)
+{
+ return inet_sk(sk)->pmtudisc != IP_PMTUDISC_INTERFACE &&
+ inet_sk(sk)->pmtudisc != IP_PMTUDISC_OMIT;
+}
+
+static inline bool ip_sk_use_pmtu(const struct sock *sk)
+{
+ return inet_sk(sk)->pmtudisc < IP_PMTUDISC_PROBE;
+}
+
+static inline bool ip_sk_ignore_df(const struct sock *sk)
+{
+ return inet_sk(sk)->pmtudisc < IP_PMTUDISC_DO ||
+ inet_sk(sk)->pmtudisc == IP_PMTUDISC_OMIT;
+}
+
+static inline unsigned int ip_dst_mtu_maybe_forward(const struct dst_entry *dst,
+ bool forwarding)
+{
+ const struct rtable *rt = container_of(dst, struct rtable, dst);
+ struct net *net = dev_net(dst->dev);
+ unsigned int mtu;
+
+ if (READ_ONCE(net->ipv4.sysctl_ip_fwd_use_pmtu) ||
+ ip_mtu_locked(dst) ||
+ !forwarding) {
+ mtu = rt->rt_pmtu;
+ if (mtu && time_before(jiffies, rt->dst.expires))
+ goto out;
+ }
+
+ /* 'forwarding = true' case should always honour route mtu */
+ mtu = dst_metric_raw(dst, RTAX_MTU);
+ if (mtu)
+ goto out;
+
+ mtu = READ_ONCE(dst->dev->mtu);
+
+ if (unlikely(ip_mtu_locked(dst))) {
+ if (rt->rt_uses_gateway && mtu > 576)
+ mtu = 576;
+ }
+
+out:
+ mtu = min_t(unsigned int, mtu, IP_MAX_MTU);
+
+ return mtu - lwtunnel_headroom(dst->lwtstate, mtu);
+}
+
+static inline unsigned int ip_skb_dst_mtu(struct sock *sk,
+ const struct sk_buff *skb)
+{
+ unsigned int mtu;
+
+ if (!sk || !sk_fullsock(sk) || ip_sk_use_pmtu(sk)) {
+ bool forwarding = IPCB(skb)->flags & IPSKB_FORWARDED;
+
+ return ip_dst_mtu_maybe_forward(skb_dst(skb), forwarding);
+ }
+
+ mtu = min(READ_ONCE(skb_dst(skb)->dev->mtu), IP_MAX_MTU);
+ return mtu - lwtunnel_headroom(skb_dst(skb)->lwtstate, mtu);
+}
+
+struct dst_metrics *ip_fib_metrics_init(struct net *net, struct nlattr *fc_mx,
+ int fc_mx_len,
+ struct netlink_ext_ack *extack);
+static inline void ip_fib_metrics_put(struct dst_metrics *fib_metrics)
+{
+ if (fib_metrics != &dst_default_metrics &&
+ refcount_dec_and_test(&fib_metrics->refcnt))
+ kfree(fib_metrics);
+}
+
+/* ipv4 and ipv6 both use refcounted metrics if it is not the default */
+static inline
+void ip_dst_init_metrics(struct dst_entry *dst, struct dst_metrics *fib_metrics)
+{
+ dst_init_metrics(dst, fib_metrics->metrics, true);
+
+ if (fib_metrics != &dst_default_metrics) {
+ dst->_metrics |= DST_METRICS_REFCOUNTED;
+ refcount_inc(&fib_metrics->refcnt);
+ }
+}
+
+static inline
+void ip_dst_metrics_put(struct dst_entry *dst)
+{
+ struct dst_metrics *p = (struct dst_metrics *)DST_METRICS_PTR(dst);
+
+ if (p != &dst_default_metrics && refcount_dec_and_test(&p->refcnt))
+ kfree(p);
+}
+
+void __ip_select_ident(struct net *net, struct iphdr *iph, int segs);
+
+static inline void ip_select_ident_segs(struct net *net, struct sk_buff *skb,
+ struct sock *sk, int segs)
+{
+ struct iphdr *iph = ip_hdr(skb);
+
+ /* We had many attacks based on IPID, use the private
+ * generator as much as we can.
+ */
+ if (sk && inet_sk(sk)->inet_daddr) {
+ int val;
+
+ /* avoid atomic operations for TCP,
+ * as we hold socket lock at this point.
+ */
+ if (sk_is_tcp(sk)) {
+ sock_owned_by_me(sk);
+ val = atomic_read(&inet_sk(sk)->inet_id);
+ atomic_set(&inet_sk(sk)->inet_id, val + segs);
+ } else {
+ val = atomic_add_return(segs, &inet_sk(sk)->inet_id);
+ }
+ iph->id = htons(val);
+ return;
+ }
+ if ((iph->frag_off & htons(IP_DF)) && !skb->ignore_df) {
+ iph->id = 0;
+ } else {
+ /* Unfortunately we need the big hammer to get a suitable IPID */
+ __ip_select_ident(net, iph, segs);
+ }
+}
+
+static inline void ip_select_ident(struct net *net, struct sk_buff *skb,
+ struct sock *sk)
+{
+ ip_select_ident_segs(net, skb, sk, 1);
+}
+
+static inline __wsum inet_compute_pseudo(struct sk_buff *skb, int proto)
+{
+ return csum_tcpudp_nofold(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr,
+ skb->len, proto, 0);
+}
+
+/* copy IPv4 saddr & daddr to flow_keys, possibly using 64bit load/store
+ * Equivalent to : flow->v4addrs.src = iph->saddr;
+ * flow->v4addrs.dst = iph->daddr;
+ */
+static inline void iph_to_flow_copy_v4addrs(struct flow_keys *flow,
+ const struct iphdr *iph)
+{
+ BUILD_BUG_ON(offsetof(typeof(flow->addrs), v4addrs.dst) !=
+ offsetof(typeof(flow->addrs), v4addrs.src) +
+ sizeof(flow->addrs.v4addrs.src));
+ memcpy(&flow->addrs.v4addrs, &iph->addrs, sizeof(flow->addrs.v4addrs));
+ flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
+}
+
+/*
+ * 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(&sk->sk_v6_rcv_saddr, 0, sizeof(sk->sk_v6_rcv_saddr));
+ }
+#endif
+}
+
+#endif
+
+static inline unsigned int ipv4_addr_hash(__be32 ip)
+{
+ return (__force unsigned int) ip;
+}
+
+static inline u32 ipv4_portaddr_hash(const struct net *net,
+ __be32 saddr,
+ unsigned int port)
+{
+ return jhash_1word((__force u32)saddr, net_hash_mix(net)) ^ port;
+}
+
+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,
+};
+
+/* Return true if the value of 'user' is between 'lower_bond'
+ * and 'upper_bond' inclusively.
+ */
+static inline bool ip_defrag_user_in_between(u32 user,
+ enum ip_defrag_users lower_bond,
+ enum ip_defrag_users upper_bond)
+{
+ return user >= lower_bond && user <= upper_bond;
+}
+
+int ip_defrag(struct net *net, struct sk_buff *skb, u32 user);
+#ifdef CONFIG_INET
+struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user);
+#else
+static inline struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user)
+{
+ return skb;
+}
+#endif
+
+/*
+ * Functions provided by ip_forward.c
+ */
+
+int ip_forward(struct sk_buff *skb);
+
+/*
+ * Functions provided by ip_options.c
+ */
+
+void ip_options_build(struct sk_buff *skb, struct ip_options *opt,
+ __be32 daddr, struct rtable *rt);
+
+int __ip_options_echo(struct net *net, struct ip_options *dopt,
+ struct sk_buff *skb, const struct ip_options *sopt);
+static inline int ip_options_echo(struct net *net, struct ip_options *dopt,
+ struct sk_buff *skb)
+{
+ return __ip_options_echo(net, dopt, skb, &IPCB(skb)->opt);
+}
+
+void ip_options_fragment(struct sk_buff *skb);
+int __ip_options_compile(struct net *net, struct ip_options *opt,
+ struct sk_buff *skb, __be32 *info);
+int ip_options_compile(struct net *net, struct ip_options *opt,
+ struct sk_buff *skb);
+int ip_options_get(struct net *net, struct ip_options_rcu **optp,
+ sockptr_t data, int optlen);
+void ip_options_undo(struct ip_options *opt);
+void ip_forward_options(struct sk_buff *skb);
+int ip_options_rcv_srr(struct sk_buff *skb, struct net_device *dev);
+
+/*
+ * Functions provided by ip_sockglue.c
+ */
+
+void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb);
+void ip_cmsg_recv_offset(struct msghdr *msg, struct sock *sk,
+ struct sk_buff *skb, int tlen, int offset);
+int ip_cmsg_send(struct sock *sk, struct msghdr *msg,
+ struct ipcm_cookie *ipc, bool allow_ipv6);
+DECLARE_STATIC_KEY_FALSE(ip4_min_ttl);
+int do_ip_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
+ unsigned int optlen);
+int ip_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
+ unsigned int optlen);
+int do_ip_getsockopt(struct sock *sk, int level, int optname,
+ sockptr_t optval, sockptr_t optlen);
+int ip_getsockopt(struct sock *sk, int level, int optname, char __user *optval,
+ int __user *optlen);
+int ip_ra_control(struct sock *sk, unsigned char on,
+ void (*destructor)(struct sock *));
+
+int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len);
+void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
+ u32 info, u8 *payload);
+void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 dport,
+ u32 info);
+
+static inline void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb)
+{
+ ip_cmsg_recv_offset(msg, skb->sk, skb, 0, 0);
+}
+
+bool icmp_global_allow(void);
+extern int sysctl_icmp_msgs_per_sec;
+extern int sysctl_icmp_msgs_burst;
+
+#ifdef CONFIG_PROC_FS
+int ip_misc_proc_init(void);
+#endif
+
+int rtm_getroute_parse_ip_proto(struct nlattr *attr, u8 *ip_proto, u8 family,
+ struct netlink_ext_ack *extack);
+
+static inline bool inetdev_valid_mtu(unsigned int mtu)
+{
+ return likely(mtu >= IPV4_MIN_MTU);
+}
+
+void ip_sock_set_freebind(struct sock *sk);
+int ip_sock_set_mtu_discover(struct sock *sk, int val);
+void ip_sock_set_pktinfo(struct sock *sk);
+void ip_sock_set_recverr(struct sock *sk);
+void ip_sock_set_tos(struct sock *sk, int val);
+void __ip_sock_set_tos(struct sock *sk, int val);
+
+#endif /* _IP_H */