statd: Introduce statd version of matchhostname()

For the near future, statd will support IPv6 but exportfs will not.
Thus statd will need a version of matchhostname() that can deal
properly with IPv6 remotes.  To reduce the risk of breaking exportfs,
introduce a separate version of matchhostname() for statd to use while
exportfs continues to use the existing AF_INET-only implementation.

Note that statd will never send matchhostname() a hostname string
containing export wildcards, so is_hostame() is not needed in the
statd version of matchhostname().  This saves some computational
expense when comparing hostnames.

A separate statd-specific implementation of matchhostname() allows
some flexibility in the long term, as well.  We might want to enrich
the matching heuristics of our SM_NOTIFY, for example, or replace
them entirely with a heuristic that is not dependent upon DNS.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

diff --git a/utils/statd/Makefile.am b/utils/statd/Makefile.am
index d9731b7f107b5125d19d6f9064171edcc99a1383..a94c01207b128f0985b3873c46b5cd93e6296c70 100644 (file)
--- a/utils/statd/Makefile.am
+++ b/utils/statd/Makefile.am
@@ -6,14 +6,13 @@ RPCPREFIX     = rpc.
 KPREFIX                = @kprefix@
 sbin_PROGRAMS  = statd sm-notify
 dist_sbin_SCRIPTS      = start-statd
-statd_SOURCES = callback.c notlist.c misc.c monitor.c \
+statd_SOURCES = callback.c notlist.c misc.c monitor.c hostname.c \
                simu.c stat.c statd.c svc_run.c rmtcall.c \
                notlist.h statd.h system.h version.h
 sm_notify_SOURCES = sm-notify.c
 
 BUILT_SOURCES = $(GENFILES)
-statd_LDADD = ../../support/export/libexport.a \
-             ../../support/nsm/libnsm.a \
+statd_LDADD = ../../support/nsm/libnsm.a \
              ../../support/nfs/libnfs.a \
              ../../support/misc/libmisc.a \
              $(LIBWRAP) $(LIBNSL)

diff --git a/utils/statd/callback.c b/utils/statd/callback.c
index 2f98aeb2adb468ae6e6d79a38a11d2a4a8346f8c..b1acd15ae8ae025bb75bf63703bfd274f0a60619 100644 (file)
--- a/utils/statd/callback.c
+++ b/utils/statd/callback.c
@@ -13,7 +13,6 @@
 #include <arpa/inet.h>
 
 #include "rpcmisc.h"
-#include "misc.h"
 #include "statd.h"
 #include "notlist.h"
 
@@ -52,8 +51,8 @@ sm_notify_1_svc(struct stat_chge *argp, struct svc_req *rqstp)
         */
        for (lp = rtnl ; lp ; lp = lp->next)
                if (NL_STATE(lp) != argp->state &&
-                   (matchhostname(argp->mon_name, lp->dns_name) ||
-                    matchhostname(ip_addr, lp->dns_name))) {
+                   (statd_matchhostname(argp->mon_name, lp->dns_name) ||
+                    statd_matchhostname(ip_addr, lp->dns_name))) {
                        NL_STATE(lp) = argp->state;
                        call = nlist_clone(lp);
                        nlist_insert(&notify, call);

diff --git a/utils/statd/hostname.c b/utils/statd/hostname.c
new file mode 100644 (file)
index 0000000..3d10d6f
--- /dev/null
+++ b/utils/statd/hostname.c
@@ -0,0 +1,119 @@
+/*
+ * 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 <strings.h>
+#include <netdb.h>
+
+#include "sockaddr.h"
+#include "statd.h"
+#include "xlog.h"
+
+/*
+ * 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;
+}
+
+/**
+ * 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;
+       struct addrinfo hint = {
+               .ai_family      = AF_UNSPEC,
+               .ai_flags       = AI_CANONNAME,
+               .ai_protocol    = (int)IPPROTO_UDP,
+       };
+       _Bool result = false;
+
+       if (strcasecmp(hostname1, hostname2) == 0) {
+               result = true;
+               goto out;
+       }
+
+       results1 = get_addrinfo(hostname1, &hint);
+       if (results1 == NULL)
+               goto out;
+       results2 = get_addrinfo(hostname2, &hint);
+       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:
+       freeaddrinfo(results2);
+       freeaddrinfo(results1);
+
+       xlog(D_CALL, "%s: hostnames %s", __func__,
+                       (result ? "matched" : "did not match"));
+       return result;
+}

diff --git a/utils/statd/monitor.c b/utils/statd/monitor.c
index f818b2b4ae69d38f282845887853ddcb53695b74..51075b591de58d468835ba0ca13cb9d192da8416 100644 (file)
--- a/utils/statd/monitor.c
+++ b/utils/statd/monitor.c
@@ -22,7 +22,6 @@
 #include <dirent.h>
 
 #include "rpcmisc.h"
-#include "misc.h"
 #include "nsm.h"
 #include "statd.h"
 #include "notlist.h"
@@ -145,7 +144,7 @@ sm_mon_1_svc(struct mon *argp, struct svc_req *rqstp)
        clnt = rtnl;
 
        while ((clnt = nlist_gethost(clnt, mon_name, 0))) {
-               if (matchhostname(NL_MY_NAME(clnt), my_name) &&
+               if (statd_matchhostname(NL_MY_NAME(clnt), my_name) &&
                    NL_MY_PROC(clnt) == id->my_proc &&
                    NL_MY_PROG(clnt) == id->my_prog &&
                    NL_MY_VERS(clnt) == id->my_vers &&
@@ -298,7 +297,7 @@ sm_unmon_1_svc(struct mon_id *argp, struct svc_req *rqstp)
         * entry winds up in the list the way I'm currently handling them.)
         */
        while ((clnt = nlist_gethost(clnt, mon_name, 0))) {
-               if (matchhostname(NL_MY_NAME(clnt), my_name) &&
+               if (statd_matchhostname(NL_MY_NAME(clnt), my_name) &&
                        NL_MY_PROC(clnt) == id->my_proc &&
                        NL_MY_PROG(clnt) == id->my_prog &&
                        NL_MY_VERS(clnt) == id->my_vers) {

diff --git a/utils/statd/notlist.c b/utils/statd/notlist.c
index 1698c26abef92166941dc39eba066b879422957c..de7d0465e60877300ba2cbf30a40516a6484f154 100644 (file)
--- a/utils/statd/notlist.c
+++ b/utils/statd/notlist.c
@@ -17,7 +17,6 @@
 #endif
 
 #include <string.h>
-#include "misc.h"
 #include "statd.h"
 #include "notlist.h"
 
@@ -234,7 +233,8 @@ nlist_gethost(notify_list *list, char *host, int myname)
        notify_list     *lp;
 
        for (lp = list; lp; lp = lp->next) {
-               if (matchhostname(host, myname? NL_MY_NAME(lp) : NL_MON_NAME(lp)))
+               if (statd_matchhostname(host,
+                               myname? NL_MY_NAME(lp) : NL_MON_NAME(lp)))
                        return lp;
        }
 

diff --git a/utils/statd/statd.h b/utils/statd/statd.h
index 542a87798a93dafba5d854f05ec268a6df080017..fd6a0846ed1bcf0b4fe55d146aa1ca6ac5ac9517 100644 (file)
--- a/utils/statd/statd.h
+++ b/utils/statd/statd.h
@@ -22,7 +22,8 @@
 /*
  * Function prototypes.
  */
-extern void    change_state(void);
+extern _Bool   statd_matchhostname(const char *hostname1, const char *hostname2);
+
 extern void    my_svc_run(void);
 extern void    notify_hosts(void);
 extern void    shuffle_dirs(void);