Esempio n. 1
0
/*
 * Find a server address that can be used by `caller' to contact
 * the local service specified by `serv_uaddr'. If `clnt_uaddr' is
 * non-NULL, it is used instead of `caller' as a hint suggesting
 * the best address (e.g. the `r_addr' field of an rpc, which
 * contains the rpcbind server address that the caller used).
 *
 * Returns the best server address as a malloc'd "universal address"
 * string which should be freed by the caller. On error, returns NULL.
 */
char *
addrmerge(struct netbuf *caller, const char *serv_uaddr, const char *clnt_uaddr,
	  const char *netid)
{
	struct ifaddrs *ifap, *ifp = NULL, *bestif;
	struct netbuf *serv_nbp = NULL, *hint_nbp = NULL, tbuf;
	struct sockaddr *caller_sa, *hint_sa, *ifsa, *ifmasksa, *serv_sa;
	struct sockaddr_storage ss;
	struct netconfig *nconf;
	char *caller_uaddr = NULL;
	const char *hint_uaddr = NULL;
	char *ret = NULL;
	int bestif_goodness;

#ifdef ND_DEBUG
	if (debugging)
		fprintf(stderr, "addrmerge(caller, %s, %s, %s\n", serv_uaddr,
		    clnt_uaddr == NULL ? "NULL" : clnt_uaddr, netid);
#endif
	caller_sa = caller->buf;
	if ((nconf = rpcbind_get_conf(netid)) == NULL)
		goto freeit;
	if ((caller_uaddr = taddr2uaddr(nconf, caller)) == NULL)
		goto freeit;

	/*
	 * Use `clnt_uaddr' as the hint if non-NULL, but ignore it if its
	 * address family is different from that of the caller.
	 */
	hint_sa = NULL;
	if (clnt_uaddr != NULL) {
		hint_uaddr = clnt_uaddr;
		if ((hint_nbp = uaddr2taddr(nconf, clnt_uaddr)) == NULL)
			goto freeit;
		hint_sa = hint_nbp->buf;
	}
	if (hint_sa == NULL || hint_sa->sa_family != caller_sa->sa_family) {
		hint_uaddr = caller_uaddr;
		hint_sa = caller->buf;
	}

#ifdef ND_DEBUG
	if (debugging)
		fprintf(stderr, "addrmerge: hint %s\n", hint_uaddr);
#endif
	/* Local caller, just return the server address. */
	if (strncmp(caller_uaddr, "0.0.0.0.", 8) == 0 ||
	    strncmp(caller_uaddr, "::.", 3) == 0 || caller_uaddr[0] == '/') {
		ret = strdup(serv_uaddr);
		goto freeit;
	}

	if (getifaddrs(&ifp) < 0)
		goto freeit;

	/*
	 * Loop through all interface addresses.  We are listening to an address
	 * if any of the following are true:
	 * a) It's a loopback address
	 * b) It was specified with the -h command line option
	 * c) There were no -h command line options.
	 *
	 * Among addresses on which we are listening, choose in order of
	 * preference an address that is:
	 *
	 * a) Equal to the hint
	 * b) A link local address with the same scope ID as the client's
	 *    address, if the client's address is also link local
	 * c) An address on the same subnet as the client's address
	 * d) A non-localhost, non-p2p address
	 * e) Any usable address
	 */
	bestif = NULL;
	bestif_goodness = 0;
	for (ifap = ifp; ifap != NULL; ifap = ifap->ifa_next) {
		ifsa = ifap->ifa_addr;
		ifmasksa = ifap->ifa_netmask;

		/* Skip addresses where we don't listen */
		if (ifsa == NULL || ifsa->sa_family != hint_sa->sa_family ||
		    !(ifap->ifa_flags & IFF_UP))
			continue;

		if (!(ifap->ifa_flags & IFF_LOOPBACK) && !listen_addr(ifsa))
			continue;

		if ((hint_sa->sa_family == AF_INET) &&
		    ((((struct sockaddr_in*)hint_sa)->sin_addr.s_addr == 
		      ((struct sockaddr_in*)ifsa)->sin_addr.s_addr))) {
			const int goodness = 4;

			bestif_goodness = goodness;
			bestif = ifap;
			goto found;
		}
#ifdef INET6
		if ((hint_sa->sa_family == AF_INET6) &&
		    (0 == memcmp(&((struct sockaddr_in6*)hint_sa)->sin6_addr,
				 &((struct sockaddr_in6*)ifsa)->sin6_addr,
				 sizeof(struct in6_addr))) &&
		    (((struct sockaddr_in6*)hint_sa)->sin6_scope_id ==
		    (((struct sockaddr_in6*)ifsa)->sin6_scope_id))) {
			const int goodness = 4;

			bestif_goodness = goodness;
			bestif = ifap;
			goto found;
		}
		if (hint_sa->sa_family == AF_INET6) {
			/*
			 * For v6 link local addresses, if the caller is on
			 * a link-local address then use the scope id to see
			 * which one.
			 */
			if (IN6_IS_ADDR_LINKLOCAL(&SA2SIN6ADDR(ifsa)) &&
			    IN6_IS_ADDR_LINKLOCAL(&SA2SIN6ADDR(caller_sa)) &&
			    IN6_IS_ADDR_LINKLOCAL(&SA2SIN6ADDR(hint_sa))) {
				if (SA2SIN6(ifsa)->sin6_scope_id ==
				    SA2SIN6(caller_sa)->sin6_scope_id) {
					const int goodness = 3;

					if (bestif_goodness < goodness) {
						bestif = ifap;
						bestif_goodness = goodness;
					}
				}
			}
		}
#endif /* INET6 */
		if (0 == bitmaskcmp(hint_sa, ifsa, ifmasksa)) {
			const int goodness = 2;

			if (bestif_goodness < goodness) {
				bestif = ifap;
				bestif_goodness = goodness;
			}
		}
		if (!(ifap->ifa_flags & (IFF_LOOPBACK | IFF_POINTOPOINT))) {
			const int goodness = 1;

			if (bestif_goodness < goodness) {
				bestif = ifap;
				bestif_goodness = goodness;
			}
		}
		if (bestif == NULL)
			bestif = ifap;
	}
	if (bestif == NULL)
		goto freeit;

found:
	/*
	 * Construct the new address using the address from
	 * `bestif', and the port number from `serv_uaddr'.
	 */
	serv_nbp = uaddr2taddr(nconf, serv_uaddr);
	if (serv_nbp == NULL)
		goto freeit;
	serv_sa = serv_nbp->buf;

	memcpy(&ss, bestif->ifa_addr, bestif->ifa_addr->sa_len);
	switch (ss.ss_family) {
	case AF_INET:
		SA2SIN(&ss)->sin_port = SA2SIN(serv_sa)->sin_port;
		break;
#ifdef INET6
	case AF_INET6:
		SA2SIN6(&ss)->sin6_port = SA2SIN6(serv_sa)->sin6_port;
		break;
#endif
	}
	tbuf.len = ss.ss_len;
	tbuf.maxlen = sizeof(ss);
	tbuf.buf = &ss;
	ret = taddr2uaddr(nconf, &tbuf);

freeit:
	if (caller_uaddr != NULL)
		free(caller_uaddr);
	if (hint_nbp != NULL) {
		free(hint_nbp->buf);
		free(hint_nbp);
	}
	if (serv_nbp != NULL) {
		free(serv_nbp->buf);
		free(serv_nbp);
	}
	if (ifp != NULL)
		freeifaddrs(ifp);

#ifdef ND_DEBUG
	if (debugging)
		fprintf(stderr, "addrmerge: returning %s\n", ret);
#endif
	return ret;
}
Esempio n. 2
0
/*
 * Find a server address that can be used by `caller' to contact
 * the local service specified by `serv_uaddr'. If `clnt_uaddr' is
 * non-NULL, it is used instead of `caller' as a hint suggesting
 * the best address (e.g. the `r_addr' field of an rpc, which
 * contains the rpcbind server address that the caller used).
 *
 * Returns the best server address as a malloc'd "universal address"
 * string which should be freed by the caller. On error, returns NULL.
 */
char *
addrmerge(arpc_addr_t *caller, const char *serv_uaddr, const char *clnt_uaddr,
	  const char *netid)
{
	struct ifaddrs *ifap, *ifp = NULL, *bestif;
	arpc_addr_t *serv_nbp = NULL, *hint_nbp = NULL, tbuf;
	struct sockaddr *caller_sa, *hint_sa, *ifsa, *ifmasksa, *serv_sa;
	struct sockaddr_storage ss;
	socklen_t len;
	const char *hint_uaddr = NULL;
	char *caller_uaddr = NULL;
	char *ret = NULL;
	int err;

#ifdef ND_DEBUG
	if (debugging)
		fprintf(stderr, "addrmerge(caller, %s, %s, %s\n", serv_uaddr,
		    clnt_uaddr == NULL ? "NULL" : clnt_uaddr, netid);
#endif
	caller_sa = (struct sockaddr *)caller->buf;

	err = ar_taddr2uaddr(rpcbind_ioctx, netid, caller, &caller_uaddr);
	if (err != 0) {
		goto freeit;
	}

	/*
	 * Use `clnt_uaddr' as the hint if non-NULL, but ignore it if its
	 * address family is different from that of the caller.
	 */
	hint_sa = NULL;
	if (clnt_uaddr != NULL) {
		hint_uaddr = clnt_uaddr;
		err = ar_uaddr2taddr(rpcbind_ioctx, netid, 
				     clnt_uaddr, &hint_nbp);
		if (err != 0) {
			goto freeit;
		}
		hint_sa = (struct sockaddr *)hint_nbp->buf;
	}
	if (hint_sa == NULL || hint_sa->sa_family != caller_sa->sa_family) {
		hint_uaddr = caller_uaddr;
		hint_sa = (struct sockaddr *)caller->buf;
	}

#ifdef ND_DEBUG
	if (debugging) {
		fprintf(stderr, "addrmerge: hint %s\n", hint_uaddr);
	}
#endif
	/* Local caller, just return the server address. */
	if (strncmp(caller_uaddr, "0.0.0.0.", 8) == 0 ||
	    strncmp(caller_uaddr, "::.", 3) == 0 || caller_uaddr[0] == '/') {
		ret = strdup(serv_uaddr);
		goto freeit;
	}

	if (getifaddrs(&ifp) < 0) {
		goto freeit;
	}

	/*
	 * 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.
	 */
	bestif = NULL;
	for (ifap = ifp; ifap != NULL; ifap = ifap->ifa_next) {
		ifsa = ifap->ifa_addr;
		ifmasksa = ifap->ifa_netmask;

		if (ifsa == NULL || ifsa->sa_family != hint_sa->sa_family ||
		    !(ifap->ifa_flags & IFF_UP)) {
			continue;
		}

		switch (hint_sa->sa_family) {
		case AF_INET:
			/*
			 * If the hint address matches this interface
			 * address/netmask, then we're done.
			 */
			if (!bitmaskcmp(&SA2SINADDR(ifsa),
			    &SA2SINADDR(hint_sa), &SA2SINADDR(ifmasksa),
			    sizeof(struct in_addr))) {
				bestif = ifap;
				goto found;
			}
			break;
		case AF_INET6:
			/*
			 * For v6 link local addresses, if the caller is on
			 * a link-local address then use the scope id to see
			 * which one.
			 */
			in6_fillscopeid(SA2SIN6(ifsa));
			if (IN6_IS_ADDR_LINKLOCAL(&SA2SIN6ADDR(ifsa)) &&
			    IN6_IS_ADDR_LINKLOCAL(&SA2SIN6ADDR(caller_sa)) &&
			    IN6_IS_ADDR_LINKLOCAL(&SA2SIN6ADDR(hint_sa))) {
				if (SA2SIN6(ifsa)->sin6_scope_id ==
				    SA2SIN6(caller_sa)->sin6_scope_id) {
					bestif = ifap;
					goto found;
				}
			} else if (!bitmaskcmp(&SA2SIN6ADDR(ifsa),
			    &SA2SIN6ADDR(hint_sa), &SA2SIN6ADDR(ifmasksa),
			    sizeof(struct in6_addr))) {
				bestif = ifap;
				goto found;
			}
			break;
		default:
			continue;
		}

		/*
		 * Remember the first possibly useful interface, preferring
		 * "normal" to point-to-point and loopback ones.
		 */
		if (bestif == NULL ||
		    (!(ifap->ifa_flags & (IFF_LOOPBACK | IFF_POINTOPOINT)) &&
		     (bestif->ifa_flags & (IFF_LOOPBACK | IFF_POINTOPOINT)))) {
			bestif = ifap;
		}
	}
	if (bestif == NULL) {
		goto freeit;
	}

found:
	/*
	 * Construct the new address using the the address from
	 * `bestif', and the port number from `serv_uaddr'.
	 */
	err = ar_uaddr2taddr(rpcbind_ioctx, netid, serv_uaddr, &serv_nbp);
	if (err != 0) {
		goto freeit;
	}
	serv_sa = (struct sockaddr *)serv_nbp->buf;

	switch (ss.ss_family) {
	case AF_INET:
		len = sizeof(struct sockaddr_in);
		memcpy(&ss, bestif->ifa_addr, len);
		SA2SIN(&ss)->sin_port = SA2SIN(serv_sa)->sin_port;
		break;
	case AF_INET6:
		len = sizeof(struct sockaddr_in6);
		memcpy(&ss, bestif->ifa_addr, len);
		SA2SIN6(&ss)->sin6_port = SA2SIN6(serv_sa)->sin6_port;
		break;
	default:
		memset(&ss, 0, sizeof(ss));
		len = 0;
		break;
	}
	tbuf.len = len;
	tbuf.maxlen = sizeof(ss);
	tbuf.buf = (char *)&ss;
	err = ar_taddr2uaddr(rpcbind_ioctx, netid, &tbuf, &ret);
	if (err != 0) {
		ret = NULL;
	}
freeit:
	if (caller_uaddr != NULL) {
		free(caller_uaddr);
	}
	if (hint_nbp != NULL) {
		if (hint_nbp->buf) {
			free(hint_nbp->buf);
		}
		free(hint_nbp);
	}
	if (serv_nbp != NULL) {
		if (serv_nbp->buf) {
			free(serv_nbp->buf);
		}
		free(serv_nbp);
	}
	if (ifp != NULL) {
		freeifaddrs(ifp);
	}

#ifdef ND_DEBUG
	if (debugging) {
		fprintf(stderr, "addrmerge: returning %s\n", ret);
	}
#endif
	return ret;
}
Esempio n. 3
0
char *
addrmerge(struct netbuf *caller, char *serv_uaddr, char *clnt_uaddr,
	  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 = (struct sockaddr *)serv_nbp->buf;
	if (clnt_uaddr != NULL) {
		clnt_nbp = uaddr2taddr(nconf, clnt_uaddr);
		if (clnt_nbp == NULL) {
			free(serv_nbp);
			return NULL;
		}
		clnt_sa = (struct sockaddr *)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 = (struct sockaddr *)
		    malloc(sizeof (struct sockaddr_storage));
		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;
			in6_fillscopeid(ifsin6);
			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:
		assert(newsin6);
		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;
}