cregit-Linux how code gets into the kernel

Release 4.12 include/net/ip.h

Directory: include/net
/*
 * 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/route.h>
#include <net/snmp.h>
#include <net/flow.h>
#include <net/flow_dissector.h>


#define IPV4_MAX_PMTU		65535U		
/* RFC 2675, Section 5.1 */

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)

	
u16			frag_max_size;
};


static inline bool ipv4_l3mdev_skb(u16 flags) { return !!(flags & IPSKB_L3SLAVE); }

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static inline unsigned int ip_hdrlen(const struct sk_buff *skb) { return ip_hdr(skb)->ihl * 4; }

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Arnaldo Carvalho de Melo24100.00%2100.00%
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struct ipcm_cookie { struct sockcm_cookie sockc; __be32 addr; int oif; struct ip_options_rcu *opt; __u8 tx_flags; __u8 ttl; __s16 tos; char priority; }; #define IPCB(skb) ((struct inet_skb_parm*)((skb)->cb)) #define PKTINFO_SKB_CB(skb) ((struct in_pktinfo *)((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; 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); int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev); int ip_local_deliver(struct sk_buff *skb); 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 *)); 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); 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, 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); }

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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); }

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Francesco Fusco41100.00%1100.00%
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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); }

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Francesco Fusco41100.00%1100.00%
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/* 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; }

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KOVACS Krisztian26100.00%1100.00%
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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); #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) u64 snmp_get_cpu_field(void __percpu *mib, int cpu, int offct); 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); }

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Raghavendra K T31100.00%1100.00%
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static inline u64 snmp_fold_field64(void __percpu *mib, int offt, size_t syncp_off) { return snmp_fold_field(mib, offt); }

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#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(struct net *net, int *low, int *high); #ifdef CONFIG_SYSCTL
static inline int inet_is_local_reserved_port(struct net *net, int port) { if (!net->ipv4.sysctl_local_reserved_ports) return 0; return test_bit(port, net->ipv4.sysctl_local_reserved_ports); }

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static inline bool sysctl_dev_name_is_allowed(const char *name) { return strcmp(name, "default") != 0 && strcmp(name, "all") != 0; }

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static inline int inet_prot_sock(struct net *net) { return net->ipv4.sysctl_ip_prot_sock; }

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#else
static inline int inet_is_local_reserved_port(struct net *net, int port) { return 0; }

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static inline int inet_prot_sock(struct net *net) { return PROT_SOCK; }

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#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) \ ((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; }

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#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; }

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Linus Torvalds (pre-git)4374.14%466.67%
Al Viro1424.14%116.67%
Arnaldo Carvalho de Melo11.72%116.67%
Total58100.00%6100.00%


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 && !(dst_metric_locked(dst, RTAX_MTU))); }

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Linus Torvalds (pre-git)3566.04%342.86%
Eric Dumazet1120.75%114.29%
David S. Miller35.66%114.29%
Alexey Kuznetsov23.77%114.29%
Satoru SATOH23.77%114.29%
Total53100.00%7100.00%


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; }

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static inline bool ip_sk_use_pmtu(const struct sock *sk) { return inet_sk(sk)->pmtudisc < IP_PMTUDISC_PROBE; }

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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; }

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static inline unsigned int ip_dst_mtu_maybe_forward(const struct dst_entry *dst, bool forwarding) { struct net *net = dev_net(dst->dev); if (net->ipv4.sysctl_ip_fwd_use_pmtu || dst_metric_locked(dst, RTAX_MTU) || !forwarding) return dst_mtu(dst); return min(dst->dev->mtu, IP_MAX_MTU); }

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static inline unsigned int ip_skb_dst_mtu(struct sock *sk, const struct sk_buff *skb) { 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); } return min(skb_dst(skb)->dev->mtu, IP_MAX_MTU); }

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u32 ip_idents_reserve(u32 hash, int segs); 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); if ((iph->frag_off & htons(IP_DF)) && !skb->ignore_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. */ if (sk && inet_sk(sk)->inet_daddr) { iph->id = htons(inet_sk(sk)->inet_id); inet_sk(sk)->inet_id += segs; } else { iph->id = 0; } } else { __ip_select_ident(net, iph, segs); } }

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Alexey Kuznetsov7162.83%114.29%
Ansis Atteka1815.93%114.29%
Eric Dumazet1513.27%228.57%
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Américo Wang10.88%114.29%
Arnaldo Carvalho de Melo10.88%114.29%
Total113100.00%7100.00%


static inline void ip_select_ident(struct net *net, struct sk_buff *skb, struct sock *sk) { ip_select_ident_segs(net, skb, sk, 1); }

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Total33100.00%4100.00%


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); }

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Tom Herbert41100.00%1100.00%
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/* 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->saddr, sizeof(flow->addrs.v4addrs)); flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS; }

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static inline __wsum inet_gro_compute_pseudo(struct sk_buff *skb, int proto) { const struct iphdr *iph = skb_gro_network_header(skb); return csum_tcpudp_nofold(iph->saddr, iph->daddr, skb_gro_len(skb), proto, 0); }

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Tom Herbert47100.00%1100.00%
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/* * 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; }

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Linus Torvalds (pre-git)7292.31%375.00%
Al Viro67.69%125.00%
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/* * 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; }

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Roland Dreier17983.64%133.33%
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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)); }

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Timo Teräs69100.00%1100.00%
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#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 }

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Arnaldo Carvalho de Melo8392.22%240.00%
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#endif
static inline unsigned int ipv4_addr_hash(__be32 ip) { return (__force unsigned int) ip; }

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David Ahern19100.00%1100.00%
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bool ip_call_ra_chain(struct sk_buff *skb); /* * Functions provided by ip_fragment.c */ enum ip_defrag_users {