/* * 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; size_t len; 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; p = kstrndup(delim + 1, len, GFP_KERNEL); if (p) { unsigned long scope_id = 0; struct net_device *dev; dev = dev_get_by_name(net, p); if (dev != NULL) { scope_id = dev->ifindex; dev_put(dev); } else { if (strict_strtoul(p, 10, &scope_id) == 0) { kfree(p); return 0; } } kfree(p); sin6->sin6_scope_id = scope_id; return 1; } return 0; } 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); } #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) { 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 strict_strtoul() 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')]; unsigned long 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(strict_strtoul(c + 1, 10, &portlo) != 0)) return 0; if (unlikely(portlo > 255)) return 0; *c = '\0'; c = strrchr(buf, '.'); if (unlikely(c == NULL)) return 0; if (unlikely(strict_strtoul(c + 1, 10, &porthi) != 0)) return 0; if (unlikely(porthi > 255)) 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);