mountd: Make NFS version checks more strict

Ensure users and programmers specify NFS version numbers correctly.
This also makes the next patch more clean.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Steve Dickson <steved@redhat.com>

diff --git a/utils/mountd/mountd.c b/utils/mountd/mountd.c
index 982b06ea143facc7937cbbd7489a25934aad09c1..753fd377331598946ade574fc0ae785b334d360f 100644 (file)
--- a/utils/mountd/mountd.c
+++ b/utils/mountd/mountd.c
@@ -71,16 +71,34 @@ static struct option longopts[] =
        { NULL, 0, 0, 0 }
 };
 
-static int nfs_version = -1;
+#define NFSVERSBIT(vers)       (0x1 << (vers - 1))
+#define NFSVERSBIT_ALL         (NFSVERSBIT(2) | NFSVERSBIT(3) | NFSVERSBIT(4))
+
+static int nfs_version = NFSVERSBIT_ALL;
+
+static int version2(void)
+{
+       return nfs_version & NFSVERSBIT(2);
+}
+
+static int version3(void)
+{
+       return nfs_version & NFSVERSBIT(3);
+}
+
+static int version_any(void)
+{
+       return nfs_version & NFSVERSBIT_ALL;
+}
 
 static void
 unregister_services (void)
 {
-       if (nfs_version & (0x1 << 1)) {
+       if (version2()) {
                pmap_unset (MOUNTPROG, MOUNTVERS);
                pmap_unset (MOUNTPROG, MOUNTVERS_POSIX);
        }
-       if (nfs_version & (0x1 << 2))
+       if (version3())
                pmap_unset (MOUNTPROG, MOUNTVERS_NFSV3);
 }
 
@@ -673,6 +691,7 @@ main(int argc, char **argv)
        int     port = 0;
        int     descriptors = 0;
        int     c;
+       int     vers;
        struct sigaction sa;
        struct rlimit rlim;
 
@@ -716,7 +735,13 @@ main(int argc, char **argv)
                        }
                        break;
                case 'N':
-                       nfs_version &= ~(1 << (atoi (optarg) - 1));
+                       vers = atoi(optarg);
+                       if (vers < 2 || vers > 4) {
+                               fprintf(stderr, "%s: bad version number: %s\n",
+                                       argv[0], optarg);
+                               usage(argv[0], 1);
+                       }
+                       nfs_version &= ~NFSVERSBIT(vers);
                        break;
                case 'n':
                        _rpcfdtype = SOCK_DGRAM;
@@ -735,7 +760,13 @@ main(int argc, char **argv)
                        num_threads = atoi (optarg);
                        break;
                case 'V':
-                       nfs_version |= 1 << (atoi (optarg) - 1);
+                       vers = atoi(optarg);
+                       if (vers < 2 || vers > 4) {
+                               fprintf(stderr, "%s: bad version number: %s\n",
+                                       argv[0], optarg);
+                               usage(argv[0], 1);
+                       }
+                       nfs_version |= NFSVERSBIT(vers);
                        break;
                case 'v':
                        printf("kmountd %s\n", VERSION);
@@ -750,7 +781,7 @@ main(int argc, char **argv)
        /* No more arguments allowed.
         * Require at least one valid version (2, 3, or 4)
         */
-       if (optind != argc || !(nfs_version & 0xE))
+       if (optind != argc || !version_any())
                usage(argv [0], 1);
 
        if (chdir(state_dir)) {
@@ -798,13 +829,13 @@ main(int argc, char **argv)
        if (new_cache)
                cache_open();
 
-       if (nfs_version & (0x1 << 1)) {
+       if (version2()) {
                rpc_init("mountd", MOUNTPROG, MOUNTVERS,
                         mount_dispatch, port);
                rpc_init("mountd", MOUNTPROG, MOUNTVERS_POSIX,
                         mount_dispatch, port);
        }
-       if (nfs_version & (0x1 << 2))
+       if (version3())
                rpc_init("mountd", MOUNTPROG, MOUNTVERS_NFSV3,
                         mount_dispatch, port);