linux/net/core/utils.c
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00

473 lines
11 KiB
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 <kuznet@ms2.inr.ac.ru>
*/
#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(net_ratelimit_state, 5 * HZ, 10);
/*
* All net warning printk()s should be guarded by this function.
*/
int net_ratelimit(void)
{
return __ratelimit(&net_ratelimit_state);
}
EXPORT_SYMBOL(net_ratelimit);
/*
* 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)
{
unsigned int l;
unsigned int val;
int i;
l = 0;
for (i = 0; i < 4; i++) {
l <<= 8;
if (*str != '\0') {
val = 0;
while (*str != '\0' && *str != '.' && *str != '\n') {
val *= 10;
val += *str - '0';
str++;
}
l |= val;
if (*str != '\0')
str++;
}
}
return htonl(l);
}
EXPORT_SYMBOL(in_aton);
#define IN6PTON_XDIGIT 0x00010000
#define IN6PTON_DIGIT 0x00020000
#define IN6PTON_COLON_MASK 0x00700000
#define IN6PTON_COLON_1 0x00100000 /* single : requested */
#define IN6PTON_COLON_2 0x00200000 /* second : requested */
#define IN6PTON_COLON_1_2 0x00400000 /* :: requested */
#define IN6PTON_DOT 0x00800000 /* . */
#define IN6PTON_DELIM 0x10000000
#define IN6PTON_NULL 0x20000000 /* first/tail */
#define IN6PTON_UNKNOWN 0x40000000
static inline int xdigit2bin(char c, int delim)
{
int val;
if (c == delim || c == '\0')
return IN6PTON_DELIM;
if (c == ':')
return IN6PTON_COLON_MASK;
if (c == '.')
return IN6PTON_DOT;
val = hex_to_bin(c);
if (val >= 0)
return val | IN6PTON_XDIGIT | (val < 10 ? IN6PTON_DIGIT : 0);
if (delim == -1)
return IN6PTON_DELIM;
return IN6PTON_UNKNOWN;
}
/**
* 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)
{
const char *s;
u8 *d;
u8 dbuf[4];
int ret = 0;
int i;
int w = 0;
if (srclen < 0)
srclen = strlen(src);
s = src;
d = dbuf;
i = 0;
while (1) {
int c;
c = xdigit2bin(srclen > 0 ? *s : '\0', delim);
if (!(c & (IN6PTON_DIGIT | IN6PTON_DOT | IN6PTON_DELIM | IN6PTON_COLON_MASK))) {
goto out;
}
if (c & (IN6PTON_DOT | IN6PTON_DELIM | IN6PTON_COLON_MASK)) {
if (w == 0)
goto out;
*d++ = w & 0xff;
w = 0;
i++;
if (c & (IN6PTON_DELIM | IN6PTON_COLON_MASK)) {
if (i != 4)
goto out;
break;
}
goto cont;
}
w = (w * 10) + c;
if ((w & 0xffff) > 255) {
goto out;
}
cont:
if (i >= 4)
goto out;
s++;
srclen--;
}
ret = 1;
memcpy(dst, dbuf, sizeof(dbuf));
out:
if (end)
*end = s;
return ret;
}
EXPORT_SYMBOL(in4_pton);
/**
* 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)
{
const char *s, *tok = NULL;
u8 *d, *dc = NULL;
u8 dbuf[16];
int ret = 0;
int i;
int state = IN6PTON_COLON_1_2 | IN6PTON_XDIGIT | IN6PTON_NULL;
int w = 0;
memset(dbuf, 0, sizeof(dbuf));
s = src;
d = dbuf;
if (srclen < 0)
srclen = strlen(src);
while (1) {
int c;
c = xdigit2bin(srclen > 0 ? *s : '\0', delim);
if (!(c & state))
goto out;
if (c & (IN6PTON_DELIM | IN6PTON_COLON_MASK)) {
/* process one 16-bit word */
if (!(state & IN6PTON_NULL)) {
*d++ = (w >> 8) & 0xff;
*d++ = w & 0xff;
}
w = 0;
if (c & IN6PTON_DELIM) {
/* We've processed last word */
break;
}
/*
* COLON_1 => XDIGIT
* COLON_2 => XDIGIT|DELIM
* COLON_1_2 => COLON_2
*/
switch (state & IN6PTON_COLON_MASK) {
case IN6PTON_COLON_2:
dc = d;
state = IN6PTON_XDIGIT | IN6PTON_DELIM;
if (dc - dbuf >= sizeof(dbuf))
state |= IN6PTON_NULL;
break;
case IN6PTON_COLON_1|IN6PTON_COLON_1_2:
state = IN6PTON_XDIGIT | IN6PTON_COLON_2;
break;
case IN6PTON_COLON_1:
state = IN6PTON_XDIGIT;
break;
case IN6PTON_COLON_1_2:
state = IN6PTON_COLON_2;
break;
default:
state = 0;
}
tok = s + 1;
goto cont;
}
if (c & IN6PTON_DOT) {
ret = in4_pton(tok ? tok : s, srclen + (int)(s - tok), d, delim, &s);
if (ret > 0) {
d += 4;
break;
}
goto out;
}
w = (w << 4) | (0xff & c);
state = IN6PTON_COLON_1 | IN6PTON_DELIM;
if (!(w & 0xf000)) {
state |= IN6PTON_XDIGIT;
}
if (!dc && d + 2 < dbuf + sizeof(dbuf)) {
state |= IN6PTON_COLON_1_2;
state &= ~IN6PTON_DELIM;
}
if (d + 2 >= dbuf + sizeof(dbuf)) {
state &= ~(IN6PTON_COLON_1|IN6PTON_COLON_1_2);
}
cont:
if ((dc && d + 4 < dbuf + sizeof(dbuf)) ||
d + 4 == dbuf + sizeof(dbuf)) {
state |= IN6PTON_DOT;
}
if (d >= dbuf + sizeof(dbuf)) {
state &= ~(IN6PTON_XDIGIT|IN6PTON_COLON_MASK);
}
s++;
srclen--;
}
i = 15; d--;
if (dc) {
while (d >= dc)
dst[i--] = *d--;
while (i >= dc - dbuf)
dst[i--] = 0;
while (i >= 0)
dst[i--] = *d--;
} else
memcpy(dst, dbuf, sizeof(dbuf));
ret = 1;
out:
if (end)
*end = s;
return ret;
}
EXPORT_SYMBOL(in6_pton);
static int inet4_pton(const char *src, u16 port_num,
struct sockaddr_storage *addr)
{
struct sockaddr_in *addr4 = (struct sockaddr_in *)addr;
int srclen = strlen(src);
if (srclen > INET_ADDRSTRLEN)
return -EINVAL;
if (in4_pton(src, srclen, (u8 *)&addr4->sin_addr.s_addr,
'\n', NULL) == 0)
return -EINVAL;
addr4->sin_family = AF_INET;
addr4->sin_port = htons(port_num);
return 0;
}
static int inet6_pton(struct net *net, const char *src, u16 port_num,
struct sockaddr_storage *addr)
{
struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)addr;
const char *scope_delim;
int srclen = strlen(src);
if (srclen > INET6_ADDRSTRLEN)
return -EINVAL;
if (in6_pton(src, srclen, (u8 *)&addr6->sin6_addr.s6_addr,
'%', &scope_delim) == 0)
return -EINVAL;
if (ipv6_addr_type(&addr6->sin6_addr) & IPV6_ADDR_LINKLOCAL &&
src + srclen != scope_delim && *scope_delim == '%') {
struct net_device *dev;
char scope_id[16];
size_t scope_len = min_t(size_t, sizeof(scope_id) - 1,
src + srclen - scope_delim - 1);
memcpy(scope_id, scope_delim + 1, scope_len);
scope_id[scope_len] = '\0';
dev = dev_get_by_name(net, scope_id);
if (dev) {
addr6->sin6_scope_id = dev->ifindex;
dev_put(dev);
} else if (kstrtouint(scope_id, 0, &addr6->sin6_scope_id)) {
return -EINVAL;
}
}
addr6->sin6_family = AF_INET6;
addr6->sin6_port = htons(port_num);
return 0;
}
/**
* 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)
{
u16 port_num;
int ret = -EINVAL;
if (port) {
if (kstrtou16(port, 0, &port_num))
return -EINVAL;
} else {
port_num = 0;
}
switch (af) {
case AF_INET:
ret = inet4_pton(src, port_num, addr);
break;
case AF_INET6:
ret = inet6_pton(net, src, port_num, addr);
break;
case AF_UNSPEC:
ret = inet4_pton(src, port_num, addr);
if (ret)
ret = inet6_pton(net, src, port_num, addr);
break;
default:
pr_err("unexpected address family %d\n", af);
}
return ret;
}
EXPORT_SYMBOL(inet_pton_with_scope);
bool inet_addr_is_any(struct sockaddr *addr)
{
if (addr->sa_family == AF_INET6) {
struct sockaddr_in6 *in6 = (struct sockaddr_in6 *)addr;
const struct sockaddr_in6 in6_any =
{ .sin6_addr = IN6ADDR_ANY_INIT };
if (!memcmp(in6->sin6_addr.s6_addr,
in6_any.sin6_addr.s6_addr, 16))
return true;
} else if (addr->sa_family == AF_INET) {
struct sockaddr_in *in = (struct sockaddr_in *)addr;
if (in->sin_addr.s_addr == htonl(INADDR_ANY))
return true;
} else {
pr_warn("unexpected address family %u\n", addr->sa_family);
}
return false;
}
EXPORT_SYMBOL(inet_addr_is_any);
void inet_proto_csum_replace4(__sum16 *sum, struct sk_buff *skb,
__be32 from, __be32 to, bool pseudohdr)
{
if (skb->ip_summed != CHECKSUM_PARTIAL) {
csum_replace4(sum, from, to);
if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr)
skb->csum = ~csum_add(csum_sub(~(skb->csum),
(__force __wsum)from),
(__force __wsum)to);
} else if (pseudohdr)
*sum = ~csum_fold(csum_add(csum_sub(csum_unfold(*sum),
(__force __wsum)from),
(__force __wsum)to));
}
EXPORT_SYMBOL(inet_proto_csum_replace4);
void inet_proto_csum_replace16(__sum16 *sum, struct sk_buff *skb,
const __be32 *from, const __be32 *to,
bool pseudohdr)
{
__be32 diff[] = {
~from[0], ~from[1], ~from[2], ~from[3],
to[0], to[1], to[2], to[3],
};
if (skb->ip_summed != CHECKSUM_PARTIAL) {
*sum = csum_fold(csum_partial(diff, sizeof(diff),
~csum_unfold(*sum)));
if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr)
skb->csum = ~csum_partial(diff, sizeof(diff),
~skb->csum);
} else if (pseudohdr)
*sum = ~csum_fold(csum_partial(diff, sizeof(diff),
csum_unfold(*sum)));
}
EXPORT_SYMBOL(inet_proto_csum_replace16);
void inet_proto_csum_replace_by_diff(__sum16 *sum, struct sk_buff *skb,
__wsum diff, bool pseudohdr)
{
if (skb->ip_summed != CHECKSUM_PARTIAL) {
*sum = csum_fold(csum_add(diff, ~csum_unfold(*sum)));
if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr)
skb->csum = ~csum_add(diff, ~skb->csum);
} else if (pseudohdr) {
*sum = ~csum_fold(csum_add(diff, csum_unfold(*sum)));
}
}
EXPORT_SYMBOL(inet_proto_csum_replace_by_diff);