/* $NetBSD: util.c,v 1.24 2020/06/17 00:16:22 kamil Exp $ */
/* $FreeBSD: head/usr.sbin/rpcbind/util.c 300973 2016-05-29 20:28:01Z ngie $ */
/*-
* Copyright (c) 2000 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Frank van der Linden.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/queue.h>
#include <net/if.h>
#include <netinet/in.h>
#include <assert.h>
#include <ifaddrs.h>
#include <poll.h>
#include <rpc/rpc.h>
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <netdb.h>
#include <netconfig.h>
#include <stdio.h>
#include <arpa/inet.h>
#include <err.h>
#ifdef RPCBIND_RUMP
#include <rump/rump.h>
#include <rump/rump_syscallshotgun.h>
#include <rump/rump_syscalls.h>
#endif
#include "rpcbind.h"
static struct sockaddr_in *local_in4;
#ifdef INET6
static struct sockaddr_in6 *local_in6;
#endif
static int bitmaskcmp(void *, void *, void *, int);
/*
* For all bits set in "mask", compare the corresponding bits in
* "dst" and "src", and see if they match. Returns 0 if the addresses
* match.
*/
static int
bitmaskcmp(void *dst, void *src, void *mask, int bytelen)
{
int i, j;
u_int8_t *p1 = dst, *p2 = src, *netmask = mask;
u_int8_t bitmask;
for (i = 0; i < bytelen; i++) {
for (j = 0; j < 8; j++) {
bitmask = 1 << j;
if (!(netmask[i] & bitmask))
continue;
if ((p1[i] & bitmask) != (p2[i] & bitmask))
return 1;
}
}
return 0;
}
char *
addrmerge(struct netbuf *caller, char *serv_uaddr, char *clnt_uaddr,
const char *netid)
{
struct ifaddrs *ifap, *ifp, *bestif;
#ifdef INET6
struct sockaddr_in6 *servsin6, *sin6mask, *clntsin6, *ifsin6, *realsin6;
struct sockaddr_in6 *newsin6;
#endif
struct sockaddr_in *servsin, *sinmask, *clntsin, *newsin, *ifsin;
struct netbuf *serv_nbp, *clnt_nbp = NULL, tbuf;
struct sockaddr *serv_sa;
struct sockaddr *clnt_sa;
struct sockaddr_storage ss;
struct netconfig *nconf;
struct sockaddr *clnt = caller->buf;
char *ret = NULL;
#ifdef INET6
servsin6 = ifsin6 = newsin6 = NULL; /* XXXGCC -Wuninitialized */
#endif
servsin = newsin = NULL; /* XXXGCC -Wuninitialized */
#ifdef RPCBIND_DEBUG
if (debugging)
fprintf(stderr, "addrmerge(caller, %s, %s, %s\n", serv_uaddr,
clnt_uaddr, netid);
#endif
nconf = getnetconfigent(netid);
if (nconf == NULL)
return NULL;
/*
* Local merge, just return a duplicate.
*/
if (clnt_uaddr != NULL && strncmp(clnt_uaddr, "0.0.0.0.", 8) == 0)
return strdup(clnt_uaddr);
serv_nbp = uaddr2taddr(nconf, serv_uaddr);
if (serv_nbp == NULL)
return NULL;
serv_sa = serv_nbp->buf;
if (clnt_uaddr != NULL) {
clnt_nbp = uaddr2taddr(nconf, clnt_uaddr);
if (clnt_nbp == NULL) {
free(serv_nbp);
return NULL;
}
clnt_sa = clnt_nbp->buf;
if (clnt_sa->sa_family == AF_LOCAL) {
free(serv_nbp);
free(clnt_nbp);
free(clnt_sa);
return strdup(serv_uaddr);
}
} else {
clnt_sa = malloc(clnt->sa_len);
if (clnt_sa == NULL) {
free(serv_nbp);
return NULL;
}
memcpy(clnt_sa, clnt, clnt->sa_len);
}
if (getifaddrs(&ifp) < 0) {
free(serv_nbp);
free(clnt_sa);
if (clnt_nbp != NULL)
free(clnt_nbp);
return 0;
}
/*
* Loop through all interfaces. For each interface, see if the
* network portion of its address is equal to that of the client.
* If so, we have found the interface that we want to use.
*/
for (ifap = ifp; ifap != NULL; ifap = ifap->ifa_next) {
if (ifap->ifa_addr->sa_family != clnt->sa_family ||
!(ifap->ifa_flags & IFF_UP))
continue;
switch (clnt->sa_family) {
case AF_INET:
/*
* realsin: address that recvfrom gave us.
* ifsin: address of interface being examined.
* clntsin: address that client want us to contact
* it on
* servsin: local address of RPC service.
* sinmask: netmask of this interface
* newsin: initially a copy of clntsin, eventually
* the merged address
*/
servsin = (struct sockaddr_in *)serv_sa;
clntsin = (struct sockaddr_in *)clnt_sa;
sinmask = (struct sockaddr_in *)ifap->ifa_netmask;
newsin = (struct sockaddr_in *)&ss;
ifsin = (struct sockaddr_in *)ifap->ifa_addr;
if (!bitmaskcmp(&ifsin->sin_addr, &clntsin->sin_addr,
&sinmask->sin_addr, sizeof (struct in_addr))) {
goto found;
}
break;
#ifdef INET6
case AF_INET6:
/*
* realsin6: address that recvfrom gave us.
* ifsin6: address of interface being examined.
* clntsin6: address that client want us to contact
* it on
* servsin6: local address of RPC service.
* sin6mask: netmask of this interface
* newsin6: initially a copy of clntsin, eventually
* the merged address
*
* For v6 link local addresses, if the client contacted
* us via a link-local address, and wants us to reply
* to one, use the scope id to see which one.
*/
realsin6 = (struct sockaddr_in6 *)clnt;
ifsin6 = (struct sockaddr_in6 *)ifap->ifa_addr;
inet6_getscopeid(ifsin6, 1);
clntsin6 = (struct sockaddr_in6 *)clnt_sa;
servsin6 = (struct sockaddr_in6 *)serv_sa;
sin6mask = (struct sockaddr_in6 *)ifap->ifa_netmask;
newsin6 = (struct sockaddr_in6 *)&ss;
if (IN6_IS_ADDR_LINKLOCAL(&ifsin6->sin6_addr) &&
IN6_IS_ADDR_LINKLOCAL(&realsin6->sin6_addr) &&
IN6_IS_ADDR_LINKLOCAL(&clntsin6->sin6_addr)) {
if (ifsin6->sin6_scope_id !=
realsin6->sin6_scope_id)
continue;
goto found;
}
if (!bitmaskcmp(&ifsin6->sin6_addr,
&clntsin6->sin6_addr, &sin6mask->sin6_addr,
sizeof (struct in6_addr)))
goto found;
break;
#endif
default:
goto freeit;
}
}
/*
* Didn't find anything. Get the first possibly useful interface,
* preferring "normal" interfaces to point-to-point and loopback
* ones.
*/
bestif = NULL;
for (ifap = ifp; ifap != NULL; ifap = ifap->ifa_next) {
if (ifap->ifa_addr->sa_family != clnt->sa_family ||
!(ifap->ifa_flags & IFF_UP))
continue;
if (!(ifap->ifa_flags & IFF_LOOPBACK) &&
!(ifap->ifa_flags & IFF_POINTOPOINT)) {
bestif = ifap;
break;
}
if (bestif == NULL)
bestif = ifap;
else if ((bestif->ifa_flags & IFF_LOOPBACK) &&
!(ifap->ifa_flags & IFF_LOOPBACK))
bestif = ifap;
}
ifap = bestif;
found:
switch (clnt->sa_family) {
case AF_INET:
memcpy(newsin, ifap->ifa_addr, clnt_sa->sa_len);
newsin->sin_port = servsin->sin_port;
tbuf.len = clnt_sa->sa_len;
tbuf.maxlen = sizeof (struct sockaddr_storage);
tbuf.buf = newsin;
break;
#ifdef INET6
case AF_INET6:
memcpy(newsin6, ifsin6, clnt_sa->sa_len);
newsin6->sin6_port = servsin6->sin6_port;
tbuf.maxlen = sizeof (struct sockaddr_storage);
tbuf.len = clnt_sa->sa_len;
tbuf.buf = newsin6;
break;
#endif
default:
goto freeit;
}
if (ifap != NULL)
ret = taddr2uaddr(nconf, &tbuf);
freeit:
freenetconfigent(nconf);
free(serv_sa);
free(serv_nbp);
if (clnt_sa != NULL)
free(clnt_sa);
if (clnt_nbp != NULL)
free(clnt_nbp);
freeifaddrs(ifp);
#ifdef RPCBIND_DEBUG
if (debugging)
fprintf(stderr, "addrmerge: returning %s\n", ret);
#endif
return ret;
}
void
network_init()
{
#ifdef INET6
struct ifaddrs *ifap, *ifp;
struct ipv6_mreq mreq6;
unsigned int ifindex;
int s;
#endif
int ecode;
struct addrinfo hints, *res;
memset(&hints, 0, sizeof hints);
hints.ai_family = AF_INET;
if ((ecode = getaddrinfo(NULL, "sunrpc", &hints, &res))) {
if (debugging)
fprintf(stderr, "can't get local ip4 address: %s\n",
gai_strerror(ecode));
} else {
local_in4 = malloc(sizeof(*local_in4));
if (local_in4 == NULL) {
if (debugging)
fprintf(stderr, "can't alloc local ip4 addr\n");
}
memcpy(local_in4, res->ai_addr, sizeof *local_in4);
}
#ifdef INET6
hints.ai_family = AF_INET6;
if ((ecode = getaddrinfo(NULL, "sunrpc", &hints, &res))) {
if (debugging)
fprintf(stderr, "can't get local ip6 address: %s\n",
gai_strerror(ecode));
} else {
local_in6 = malloc(sizeof(*local_in6));
if (local_in6 == NULL) {
if (debugging)
fprintf(stderr, "can't alloc local ip6 addr\n");
}
memcpy(local_in6, res->ai_addr, sizeof *local_in6);
}
/*
* Now join the RPC ipv6 multicast group on all interfaces.
*/
if (getifaddrs(&ifp) < 0)
return;
mreq6.ipv6mr_interface = 0;
inet_pton(AF_INET6, RPCB_MULTICAST_ADDR, &mreq6.ipv6mr_multiaddr);
s = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP);
/*
* Loop through all interfaces. For each interface, see if the
* network portion of its address is equal to that of the client.
* If so, we have found the interface that we want to use.
*/
for (ifap = ifp; ifap != NULL; ifap = ifap->ifa_next) {
if (ifap->ifa_addr->sa_family != AF_INET6 ||
!(ifap->ifa_flags & IFF_MULTICAST))
continue;
ifindex = if_nametoindex(ifap->ifa_name);
if (ifindex == mreq6.ipv6mr_interface)
/*
* Already did this one.
*/
continue;
mreq6.ipv6mr_interface = ifindex;
if (setsockopt(s, IPPROTO_IPV6, IPV6_JOIN_GROUP, &mreq6,
sizeof mreq6) < 0)
if (debugging)
warn("setsockopt v6 multicast");
}
freeifaddrs(ifp);
#endif
/* close(s); */
}
struct sockaddr *
local_sa(int af)
{
switch (af) {
case AF_INET:
return (struct sockaddr *)local_in4;
#ifdef INET6
case AF_INET6:
return (struct sockaddr *)local_in6;
#endif
default:
return NULL;
}
}
