linux/net/sunrpc/addr.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright 2009, Oracle.  All rights reserved.
 *
 * Convert socket addresses to presentation addresses and universal
 * addresses, and vice versa.
 *
 * Universal addresses are introduced by RFC 1833 and further refined by
 * recent RFCs describing NFSv4.  The universal address format is part
 * of the external (network) interface provided by rpcbind version 3
 * and 4, and by NFSv4.  Such an address is a string containing a
 * presentation format IP address followed by a port number in
 * "hibyte.lobyte" format.
 *
 * IPv6 addresses can also include a scope ID, typically denoted by
 * a '%' followed by a device name or a non-negative integer.  Refer to
 * RFC 4291, Section 2.2 for details on IPv6 presentation formats.
 */

#include <net/ipv6.h>
#include <linux/sunrpc/addr.h>
#include <linux/sunrpc/msg_prot.h>
#include <linux/slab.h>
#include <linux/export.h>

#if IS_ENABLED(CONFIG_IPV6)

static size_t rpc_ntop6_noscopeid(const struct sockaddr *sap,
				  char *buf, const int buflen)
{ … }

static size_t rpc_ntop6(const struct sockaddr *sap,
			char *buf, const size_t buflen)
{ … }

#else	/* !IS_ENABLED(CONFIG_IPV6) */

static size_t rpc_ntop6_noscopeid(const struct sockaddr *sap,
				  char *buf, const int buflen)
{
	return 0;
}

static size_t rpc_ntop6(const struct sockaddr *sap,
			char *buf, const size_t buflen)
{
	return 0;
}

#endif	/* !IS_ENABLED(CONFIG_IPV6) */

static int rpc_ntop4(const struct sockaddr *sap,
		     char *buf, const size_t buflen)
{ … }

/**
 * rpc_ntop - construct a presentation address in @buf
 * @sap: socket address
 * @buf: construction area
 * @buflen: size of @buf, in bytes
 *
 * Plants a %NUL-terminated string in @buf and returns the length
 * of the string, excluding the %NUL.  Otherwise zero is returned.
 */
size_t rpc_ntop(const struct sockaddr *sap, char *buf, const size_t buflen)
{ … }
EXPORT_SYMBOL_GPL(…);

static size_t rpc_pton4(const char *buf, const size_t buflen,
			struct sockaddr *sap, const size_t salen)
{ … }

#if IS_ENABLED(CONFIG_IPV6)
static int rpc_parse_scope_id(struct net *net, const char *buf,
			      const size_t buflen, const char *delim,
			      struct sockaddr_in6 *sin6)
{ … }

static size_t rpc_pton6(struct net *net, const char *buf, const size_t buflen,
			struct sockaddr *sap, const size_t salen)
{ … }
#else
static size_t rpc_pton6(struct net *net, const char *buf, const size_t buflen,
			struct sockaddr *sap, const size_t salen)
{
	return 0;
}
#endif

/**
 * rpc_pton - Construct a sockaddr in @sap
 * @net: applicable network namespace
 * @buf: C string containing presentation format IP address
 * @buflen: length of presentation address in bytes
 * @sap: buffer into which to plant socket address
 * @salen: size of buffer in bytes
 *
 * Returns the size of the socket address if successful; otherwise
 * zero is returned.
 *
 * Plants a socket address in @sap and returns the size of the
 * socket address, if successful.  Returns zero if an error
 * occurred.
 */
size_t rpc_pton(struct net *net, const char *buf, const size_t buflen,
		struct sockaddr *sap, const size_t salen)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * rpc_sockaddr2uaddr - Construct a universal address string from @sap.
 * @sap: socket address
 * @gfp_flags: allocation mode
 *
 * Returns a %NUL-terminated string in dynamically allocated memory;
 * otherwise NULL is returned if an error occurred.  Caller must
 * free the returned string.
 */
char *rpc_sockaddr2uaddr(const struct sockaddr *sap, gfp_t gfp_flags)
{ … }

/**
 * rpc_uaddr2sockaddr - convert a universal address to a socket address.
 * @net: applicable network namespace
 * @uaddr: C string containing universal address to convert
 * @uaddr_len: length of universal address string
 * @sap: buffer into which to plant socket address
 * @salen: size of buffer
 *
 * @uaddr does not have to be '\0'-terminated, but kstrtou8() and
 * rpc_pton() require proper string termination to be successful.
 *
 * Returns the size of the socket address if successful; otherwise
 * zero is returned.
 */
size_t rpc_uaddr2sockaddr(struct net *net, const char *uaddr,
			  const size_t uaddr_len, struct sockaddr *sap,
			  const size_t salen)
{ … }
EXPORT_SYMBOL_GPL(…);