linux/net/core/utils.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *	Generic address resultion entity
 *
 *	Authors:
 *	net_random Alan Cox
 *	net_ratelimit Andi Kleen
 *	in{4,6}_pton YOSHIFUJI Hideaki, Copyright (C)2006 USAGI/WIDE Project
 *
 *	Created by Alexey Kuznetsov <[email protected]>
 */

#include <linux/module.h>
#include <linux/jiffies.h>
#include <linux/kernel.h>
#include <linux/ctype.h>
#include <linux/inet.h>
#include <linux/mm.h>
#include <linux/net.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/percpu.h>
#include <linux/init.h>
#include <linux/ratelimit.h>
#include <linux/socket.h>

#include <net/sock.h>
#include <net/net_ratelimit.h>
#include <net/ipv6.h>

#include <asm/byteorder.h>
#include <linux/uaccess.h>

DEFINE_RATELIMIT_STATE(…);
/*
 * All net warning printk()s should be guarded by this function.
 */
int net_ratelimit(void)
{ … }
EXPORT_SYMBOL(…);

/*
 * Convert an ASCII string to binary IP.
 * This is outside of net/ipv4/ because various code that uses IP addresses
 * is otherwise not dependent on the TCP/IP stack.
 */

__be32 in_aton(const char *str)
{ … }
EXPORT_SYMBOL(…);

#define IN6PTON_XDIGIT …
#define IN6PTON_DIGIT …
#define IN6PTON_COLON_MASK …
#define IN6PTON_COLON_1 …
#define IN6PTON_COLON_2 …
#define IN6PTON_COLON_1_2 …
#define IN6PTON_DOT …
#define IN6PTON_DELIM …
#define IN6PTON_NULL …
#define IN6PTON_UNKNOWN …

static inline int xdigit2bin(char c, int delim)
{ … }

/**
 * in4_pton - convert an IPv4 address from literal to binary representation
 * @src: the start of the IPv4 address string
 * @srclen: the length of the string, -1 means strlen(src)
 * @dst: the binary (u8[4] array) representation of the IPv4 address
 * @delim: the delimiter of the IPv4 address in @src, -1 means no delimiter
 * @end: A pointer to the end of the parsed string will be placed here
 *
 * Return one on success, return zero when any error occurs
 * and @end will point to the end of the parsed string.
 *
 */
int in4_pton(const char *src, int srclen,
	     u8 *dst,
	     int delim, const char **end)
{ … }
EXPORT_SYMBOL(…);

/**
 * in6_pton - convert an IPv6 address from literal to binary representation
 * @src: the start of the IPv6 address string
 * @srclen: the length of the string, -1 means strlen(src)
 * @dst: the binary (u8[16] array) representation of the IPv6 address
 * @delim: the delimiter of the IPv6 address in @src, -1 means no delimiter
 * @end: A pointer to the end of the parsed string will be placed here
 *
 * Return one on success, return zero when any error occurs
 * and @end will point to the end of the parsed string.
 *
 */
int in6_pton(const char *src, int srclen,
	     u8 *dst,
	     int delim, const char **end)
{ … }
EXPORT_SYMBOL(…);

static int inet4_pton(const char *src, u16 port_num,
		struct sockaddr_storage *addr)
{ … }

static int inet6_pton(struct net *net, const char *src, u16 port_num,
		struct sockaddr_storage *addr)
{ … }

/**
 * inet_pton_with_scope - convert an IPv4/IPv6 and port to socket address
 * @net: net namespace (used for scope handling)
 * @af: address family, AF_INET, AF_INET6 or AF_UNSPEC for either
 * @src: the start of the address string
 * @port: the start of the port string (or NULL for none)
 * @addr: output socket address
 *
 * Return zero on success, return errno when any error occurs.
 */
int inet_pton_with_scope(struct net *net, __kernel_sa_family_t af,
		const char *src, const char *port, struct sockaddr_storage *addr)
{ … }
EXPORT_SYMBOL(…);

bool inet_addr_is_any(struct sockaddr *addr)
{ … }
EXPORT_SYMBOL(…);

void inet_proto_csum_replace4(__sum16 *sum, struct sk_buff *skb,
			      __be32 from, __be32 to, bool pseudohdr)
{ … }
EXPORT_SYMBOL(…);

/**
 * inet_proto_csum_replace16 - update layer 4 header checksum field
 * @sum: Layer 4 header checksum field
 * @skb: sk_buff for the packet
 * @from: old IPv6 address
 * @to: new IPv6 address
 * @pseudohdr: True if layer 4 header checksum includes pseudoheader
 *
 * Update layer 4 header as per the update in IPv6 src/dst address.
 *
 * There is no need to update skb->csum in this function, because update in two
 * fields a.) IPv6 src/dst address and b.) L4 header checksum cancels each other
 * for skb->csum calculation. Whereas inet_proto_csum_replace4 function needs to
 * update skb->csum, because update in 3 fields a.) IPv4 src/dst address,
 * b.) IPv4 Header checksum and c.) L4 header checksum results in same diff as
 * L4 Header checksum for skb->csum calculation.
 */
void inet_proto_csum_replace16(__sum16 *sum, struct sk_buff *skb,
			       const __be32 *from, const __be32 *to,
			       bool pseudohdr)
{ … }
EXPORT_SYMBOL(…);

void inet_proto_csum_replace_by_diff(__sum16 *sum, struct sk_buff *skb,
				     __wsum diff, bool pseudohdr)
{ … }
EXPORT_SYMBOL(…);