// 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){	const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;	const struct in6_addr *addr = &sin6->sin6_addr; 	/*	 * RFC 4291, Section 2.2.2	 *	 * Shorthanded ANY address	 */	if (ipv6_addr_any(addr))		return snprintf(buf, buflen, "::"); 	/*	 * RFC 4291, Section 2.2.2	 *	 * Shorthanded loopback address	 */	if (ipv6_addr_loopback(addr))		return snprintf(buf, buflen, "::1"); 	/*	 * RFC 4291, Section 2.2.3	 *	 * Special presentation address format for mapped v4	 * addresses.	 */	if (ipv6_addr_v4mapped(addr))		return snprintf(buf, buflen, "::ffff:%pI4",					&addr->s6_addr32[3]); 	/*	 * RFC 4291, Section 2.2.1	 */	return snprintf(buf, buflen, "%pI6c", addr);} static size_t rpc_ntop6(const struct sockaddr *sap,			char *buf, const size_t buflen){	const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;	char scopebuf[IPV6_SCOPE_ID_LEN];	size_t len;	int rc; 	len = rpc_ntop6_noscopeid(sap, buf, buflen);	if (unlikely(len == 0))		return len; 	if (!(ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL))		return len;	if (sin6->sin6_scope_id == 0)		return len; 	rc = snprintf(scopebuf, sizeof(scopebuf), "%c%u",			IPV6_SCOPE_DELIMITER, sin6->sin6_scope_id);	if (unlikely((size_t)rc >= sizeof(scopebuf)))		return 0; 	len += rc;	if (unlikely(len >= buflen))		return 0; 	strcat(buf, scopebuf);	return len;} #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){	const struct sockaddr_in *sin = (struct sockaddr_in *)sap; 	return snprintf(buf, buflen, "%pI4", &sin->sin_addr);} /** * 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){	switch (sap->sa_family) {	case AF_INET:		return rpc_ntop4(sap, buf, buflen);	case AF_INET6:		return rpc_ntop6(sap, buf, buflen);	} 	return 0;}EXPORT_SYMBOL_GPL(rpc_ntop); static size_t rpc_pton4(const char *buf, const size_t buflen,			struct sockaddr *sap, const size_t salen){	struct sockaddr_in *sin = (struct sockaddr_in *)sap;	u8 *addr = (u8 *)&sin->sin_addr.s_addr; 	if (buflen > INET_ADDRSTRLEN || salen < sizeof(struct sockaddr_in))		return 0; 	memset(sap, 0, sizeof(struct sockaddr_in)); 	if (in4_pton(buf, buflen, addr, '\0', NULL) == 0)		return 0; 	sin->sin_family = AF_INET;	return sizeof(struct sockaddr_in);} #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){	char p[IPV6_SCOPE_ID_LEN + 1];	size_t len;	u32 scope_id = 0;	struct net_device *dev; 	if ((buf + buflen) == delim)		return 1; 	if (*delim != IPV6_SCOPE_DELIMITER)		return 0; 	if (!(ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL))		return 0; 	len = (buf + buflen) - delim - 1;	if (len > IPV6_SCOPE_ID_LEN)		return 0; 	memcpy(p, delim + 1, len);	p[len] = 0; 	dev = dev_get_by_name(net, p);	if (dev != NULL) {		scope_id = dev->ifindex;		dev_put(dev);	} else {		if (kstrtou32(p, 10, &scope_id) != 0)			return 0;	} 	sin6->sin6_scope_id = scope_id;	return 1;} static size_t rpc_pton6(struct net *net, const char *buf, const size_t buflen,			struct sockaddr *sap, const size_t salen){	struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;	u8 *addr = (u8 *)&sin6->sin6_addr.in6_u;	const char *delim; 	if (buflen > (INET6_ADDRSTRLEN + IPV6_SCOPE_ID_LEN) ||	    salen < sizeof(struct sockaddr_in6))		return 0; 	memset(sap, 0, sizeof(struct sockaddr_in6)); 	if (in6_pton(buf, buflen, addr, IPV6_SCOPE_DELIMITER, &delim) == 0)		return 0; 	if (!rpc_parse_scope_id(net, buf, buflen, delim, sin6))		return 0; 	sin6->sin6_family = AF_INET6;	return sizeof(struct sockaddr_in6);}#elsestatic 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){	unsigned int i; 	for (i = 0; i < buflen; i++)		if (buf[i] == ':')			return rpc_pton6(net, buf, buflen, sap, salen);	return rpc_pton4(buf, buflen, sap, salen);}EXPORT_SYMBOL_GPL(rpc_pton); /** * 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){	char portbuf[RPCBIND_MAXUADDRPLEN];	char addrbuf[RPCBIND_MAXUADDRLEN];	unsigned short port; 	switch (sap->sa_family) {	case AF_INET:		if (rpc_ntop4(sap, addrbuf, sizeof(addrbuf)) == 0)			return NULL;		port = ntohs(((struct sockaddr_in *)sap)->sin_port);		break;	case AF_INET6:		if (rpc_ntop6_noscopeid(sap, addrbuf, sizeof(addrbuf)) == 0)			return NULL;		port = ntohs(((struct sockaddr_in6 *)sap)->sin6_port);		break;	default:		return NULL;	} 	if (snprintf(portbuf, sizeof(portbuf),		     ".%u.%u", port >> 8, port & 0xff) >= (int)sizeof(portbuf))		return NULL; 	if (strlcat(addrbuf, portbuf, sizeof(addrbuf)) >= sizeof(addrbuf))		return NULL; 	return kstrdup(addrbuf, 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){	char *c, buf[RPCBIND_MAXUADDRLEN + sizeof('\0')];	u8 portlo, porthi;	unsigned short port; 	if (uaddr_len > RPCBIND_MAXUADDRLEN)		return 0; 	memcpy(buf, uaddr, uaddr_len); 	buf[uaddr_len] = '\0';	c = strrchr(buf, '.');	if (unlikely(c == NULL))		return 0;	if (unlikely(kstrtou8(c + 1, 10, &portlo) != 0))		return 0; 	*c = '\0';	c = strrchr(buf, '.');	if (unlikely(c == NULL))		return 0;	if (unlikely(kstrtou8(c + 1, 10, &porthi) != 0))		return 0; 	port = (unsigned short)((porthi << 8) | portlo); 	*c = '\0';	if (rpc_pton(net, buf, strlen(buf), sap, salen) == 0)		return 0; 	switch (sap->sa_family) {	case AF_INET:		((struct sockaddr_in *)sap)->sin_port = htons(port);		return sizeof(struct sockaddr_in);	case AF_INET6:		((struct sockaddr_in6 *)sap)->sin6_port = htons(port);		return sizeof(struct sockaddr_in6);	} 	return 0;}EXPORT_SYMBOL_GPL(rpc_uaddr2sockaddr);