1 files changed, 319 insertions, 0 deletions
diff --git a/utils/statd/hostname.c b/utils/statd/hostname.c
new file mode 100644
index 0000000..16e21fc
--- /dev/null
+++ b/utils/statd/hostname.c
@@ -0,0 +1,319 @@
+/*
+ * Copyright 2009 Oracle.  All rights reserved.
+ *
+ * This file is part of nfs-utils.
+ *
+ * nfs-utils is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * nfs-utils is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with nfs-utils.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/*
+ * NSM for Linux.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <sys/types.h>
+#include <sys/socket.h>
+
+#include <stdlib.h>
+#include <stdbool.h>
+#include <string.h>
+#include <strings.h>
+#include <netdb.h>
+#include <arpa/inet.h>
+
+#include "nfslib.h"
+#include "sockaddr.h"
+#include "statd.h"
+#include "xlog.h"
+
+/**
+ * statd_present_address - convert sockaddr to presentation address
+ * @sap: pointer to socket address to convert
+ * @buf: pointer to buffer to fill in
+ * @buflen: length of buffer
+ *
+ * Convert the passed-in sockaddr-style address to presentation format.
+ * The presentation format address is placed in @buf and is
+ * '\0'-terminated.
+ *
+ * Returns true if successful; otherwise false.
+ *
+ * getnameinfo(3) is preferred, since it can parse IPv6 scope IDs.
+ * An alternate version of statd_present_address() is available to
+ * handle older glibcs that do not have getnameinfo(3).
+ */
+#ifdef HAVE_GETNAMEINFO
+_Bool
+statd_present_address(const struct sockaddr *sap, char *buf, const size_t buflen)
+{
+	socklen_t salen;
+	int error;
+
+	salen = nfs_sockaddr_length(sap);
+	if (salen == 0) {
+		xlog(D_GENERAL, "%s: unsupported address family",
+				__func__);
+		return false;
+	}
+
+	error = getnameinfo(sap, salen, buf, (socklen_t)buflen,
+						NULL, 0, NI_NUMERICHOST);
+	if (error != 0) {
+		xlog(D_GENERAL, "%s: getnameinfo(3): %s",
+				__func__, gai_strerror(error));
+		return false;
+	}
+	return true;
+}
+#else	/* !HAVE_GETNAMEINFO */
+_Bool
+statd_present_address(const struct sockaddr *sap, char *buf, const size_t buflen)
+{
+	const struct sockaddr_in *sin = (const struct sockaddr_in *)sap;
+
+	if (sin->sin_family != AF_INET) {
+		xlog(D_GENERAL, "%s: unsupported address family", __func__);
+		return false;
+	}
+
+	/* ensure '\0' termination */
+	memset(buf, 0, buflen);
+
+	if (inet_ntop(AF_INET, (char *)&sin->sin_addr,
+					buf, (socklen_t)buflen) == NULL) {
+		xlog(D_GENERAL, "%s: inet_ntop(3): %m", __func__);
+		return false;
+	}
+	return true;
+}
+#endif	/* !HAVE_GETNAMEINFO */
+
+/*
+ * Look up the hostname; report exceptional errors.  Caller must
+ * call freeaddrinfo(3) if a valid addrinfo is returned.
+ */
+__attribute__((__malloc__))
+static struct addrinfo *
+get_addrinfo(const char *hostname, const struct addrinfo *hint)
+{
+	struct addrinfo *ai = NULL;
+	int error;
+
+	error = getaddrinfo(hostname, NULL, hint, &ai);
+	switch (error) {
+	case 0:
+		return ai;
+	case EAI_NONAME:
+		break;
+	default:
+		xlog(D_GENERAL, "%s: failed to resolve host %s: %s",
+				__func__, hostname, gai_strerror(error));
+	}
+
+	return NULL;
+}
+
+#ifdef HAVE_GETNAMEINFO
+static _Bool
+get_nameinfo(const struct sockaddr *sap, const socklen_t salen,
+		/*@out@*/ char *buf, const socklen_t buflen)
+{
+	int error;
+
+	error = getnameinfo(sap, salen, buf, buflen, NULL, 0, NI_NAMEREQD);
+	if (error != 0) {
+		xlog(D_GENERAL, "%s: failed to resolve address: %s",
+				__func__, gai_strerror(error));
+		return false;
+	}
+
+	return true;
+}
+#else	/* !HAVE_GETNAMEINFO */
+static _Bool
+get_nameinfo(const struct sockaddr *sap,
+		__attribute__ ((unused)) const socklen_t salen,
+		/*@out@*/ char *buf, socklen_t buflen)
+{
+	struct sockaddr_in *sin = (struct sockaddr_in *)(char *)sap;
+	struct hostent *hp;
+
+	if (sin->sin_family != AF_INET) {
+		xlog(D_GENERAL, "%s: unknown address family: %d",
+				sin->sin_family);
+		return false;
+	}
+
+	hp = gethostbyaddr((const char *)&(sin->sin_addr.s_addr),
+				sizeof(struct in_addr), AF_INET);
+	if (hp == NULL) {
+		xlog(D_GENERAL, "%s: failed to resolve address: %m", __func__);
+		return false;
+	}
+
+	strncpy(buf, hp->h_name, (size_t)buflen);
+	return true;
+}
+#endif	/* !HAVE_GETNAMEINFO */
+
+/**
+ * statd_canonical_name - choose file name for monitor record files
+ * @hostname: C string containing hostname or presentation address
+ *
+ * Returns a '\0'-terminated ASCII string containing a fully qualified
+ * canonical hostname, or NULL if @hostname does not have a reverse
+ * mapping.  Caller must free the result with free(3).
+ *
+ * Incoming hostnames are looked up to determine the canonical hostname,
+ * and incoming presentation addresses are converted to canonical
+ * hostnames.
+ */
+__attribute__((__malloc__))
+char *
+statd_canonical_name(const char *hostname)
+{
+	struct addrinfo hint = {
+#ifdef IPV6_SUPPORTED
+		.ai_family	= AF_UNSPEC,
+#else	/* !IPV6_SUPPORTED */
+		.ai_family	= AF_INET,
+#endif	/* !IPV6_SUPPORTED */
+		.ai_flags	= AI_NUMERICHOST,
+		.ai_protocol	= (int)IPPROTO_UDP,
+	};
+	char buf[NI_MAXHOST];
+	struct addrinfo *ai;
+
+	ai = get_addrinfo(hostname, &hint);
+	if (ai != NULL) {
+		/* @hostname was a presentation address */
+		_Bool result;
+		result = get_nameinfo(ai->ai_addr, ai->ai_addrlen,
+					buf, (socklen_t)sizeof(buf));
+		nfs_freeaddrinfo(ai);
+		if (!result || buf[0] == '\0')
+			/* OK to use presentation address,
+			 * if no reverse map exists */
+			return strdup(hostname);
+		return strdup(buf);
+	}
+
+	/* @hostname was a hostname */
+	hint.ai_flags = AI_CANONNAME;
+	ai = get_addrinfo(hostname, &hint);
+	if (ai == NULL)
+		return NULL;
+	strcpy(buf, ai->ai_canonname);
+	nfs_freeaddrinfo(ai);
+
+	return strdup(buf);
+}
+
+/*
+ * Take care to perform an explicit reverse lookup on presentation
+ * addresses.  Otherwise we don't get a real canonical name or a
+ * complete list of addresses.
+ *
+ * Returns an addrinfo list that has ai_canonname filled in, or
+ * NULL if some error occurs.  Caller must free the returned
+ * list with freeaddrinfo(3).
+ */
+__attribute__((__malloc__))
+static struct addrinfo *
+statd_canonical_list(const char *hostname)
+{
+	struct addrinfo hint = {
+#ifdef IPV6_SUPPORTED
+		.ai_family	= AF_UNSPEC,
+#else	/* !IPV6_SUPPORTED */
+		.ai_family	= AF_INET,
+#endif	/* !IPV6_SUPPORTED */
+		.ai_flags	= AI_NUMERICHOST,
+		.ai_protocol	= (int)IPPROTO_UDP,
+	};
+	char buf[NI_MAXHOST];
+	struct addrinfo *ai;
+
+	ai = get_addrinfo(hostname, &hint);
+	if (ai != NULL) {
+		/* @hostname was a presentation address */
+		_Bool result;
+		result = get_nameinfo(ai->ai_addr, ai->ai_addrlen,
+					buf, (socklen_t)sizeof(buf));
+		nfs_freeaddrinfo(ai);
+		if (result)
+			goto out;
+	}
+	/* @hostname was a hostname or had no reverse mapping */
+	strcpy(buf, hostname);
+
+out:
+	hint.ai_flags = AI_CANONNAME;
+	return get_addrinfo(buf, &hint);
+}
+
+/**
+ * statd_matchhostname - check if two hostnames are equivalent
+ * @hostname1: C string containing hostname
+ * @hostname2: C string containing hostname
+ *
+ * Returns true if the hostnames are the same, the hostnames resolve
+ * to the same canonical name, or the hostnames resolve to at least
+ * one address that is the same.  False is returned if the hostnames
+ * do not match in any of these ways, if either hostname contains
+ * wildcard characters, if either hostname is a netgroup name, or
+ * if an error occurs.
+ */
+_Bool
+statd_matchhostname(const char *hostname1, const char *hostname2)
+{
+	struct addrinfo *ai1, *ai2, *results1 = NULL, *results2 = NULL;
+	_Bool result = false;
+
+	if (strcasecmp(hostname1, hostname2) == 0) {
+		result = true;
+		goto out;
+	}
+
+	results1 = statd_canonical_list(hostname1);
+	if (results1 == NULL)
+		goto out;
+	results2 = statd_canonical_list(hostname2);
+	if (results2 == NULL)
+		goto out;
+
+	if (strcasecmp(results1->ai_canonname, results2->ai_canonname) == 0) {
+		result = true;
+		goto out;
+	}
+
+	for (ai1 = results1; ai1 != NULL; ai1 = ai1->ai_next)
+		for (ai2 = results2; ai2 != NULL; ai2 = ai2->ai_next)
+			if (nfs_compare_sockaddr(ai1->ai_addr, ai2->ai_addr)) {
+				result = true;
+				break;
+			}
+
+out:
+	nfs_freeaddrinfo(results2);
+	nfs_freeaddrinfo(results1);
+
+	xlog(D_CALL, "%s: hostnames %s and %s %s", __func__,
+			hostname1, hostname2,
+			(result ? "matched" : "did not match"));
+	return result;
+}