net/utils: generic inet_pton_with_scope helper

Several locations in the stack need to handle ipv4/ipv6
(with scope) and port strings conversion to sockaddr.
Add a helper that takes either AF_INET, AF_INET6 or
AF_UNSPEC (for wildcard) to centralize this handling.

Suggested-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
This commit is contained in:
Sagi Grimberg 2017-02-05 21:47:22 +02:00 committed by Jens Axboe
parent 297186d640
commit b1a951fe46
2 changed files with 109 additions and 0 deletions

View File

@ -43,6 +43,8 @@
#define _LINUX_INET_H
#include <linux/types.h>
#include <net/net_namespace.h>
#include <linux/socket.h>
/*
* These mimic similar macros defined in user-space for inet_ntop(3).
@ -54,4 +56,8 @@
extern __be32 in_aton(const char *str);
extern int in4_pton(const char *src, int srclen, u8 *dst, int delim, const char **end);
extern int in6_pton(const char *src, int srclen, u8 *dst, int delim, const char **end);
extern int inet_pton_with_scope(struct net *net, unsigned short af,
const char *src, const char *port, struct sockaddr_storage *addr);
#endif /* _LINUX_INET_H */

View File

@ -26,9 +26,11 @@
#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>
@ -300,6 +302,107 @@ out:
}
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),
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);
void inet_proto_csum_replace4(__sum16 *sum, struct sk_buff *skb,
__be32 from, __be32 to, bool pseudohdr)
{