}
/*
- * Attempt an NFSv2/3 mount via a mount(2) system call.
+ * Reconstruct the mount option string based on a portmapper probe
+ * of the server. Returns one if the server's portmapper returned
+ * something we can use, otherwise zero.
+ *
+ * To handle version and transport protocol fallback properly, we
+ * need to parse some of the mount options in order to set up a
+ * portmap probe. Mount options that rewrite_mount_options()
+ * doesn't recognize are left alone.
+ *
+ * Returns a new group of mount options if successful; otherwise
+ * NULL is returned if some failure occurred.
+ */
+static struct mount_options *rewrite_mount_options(char *str)
+{
+ struct mount_options *options;
+ char *option, new_option[64];
+ clnt_addr_t mnt_server = { };
+ clnt_addr_t nfs_server = { };
+ int p;
+
+ options = po_split(str);
+ if (!options)
+ return NULL;
+
+ option = po_get(options, "addr");
+ if (option) {
+ nfs_server.saddr.sin_family = AF_INET;
+ if (!inet_aton((const char *)option, &nfs_server.saddr.sin_addr))
+ goto err;
+ } else
+ goto err;
+
+ option = po_get(options, "mountaddr");
+ if (option) {
+ mnt_server.saddr.sin_family = AF_INET;
+ if (!inet_aton((const char *)option, &mnt_server.saddr.sin_addr))
+ goto err;
+ } else
+ memcpy(&mnt_server.saddr, &nfs_server.saddr,
+ sizeof(mnt_server.saddr));
+
+ option = po_get(options, "mountport");
+ if (option)
+ mnt_server.pmap.pm_port = atoi(option);
+ mnt_server.pmap.pm_prog = MOUNTPROG;
+ option = po_get(options, "mountprog");
+ if (option)
+ mnt_server.pmap.pm_prog = atoi(option);
+ option = po_get(options, "mountvers");
+ if (option)
+ mnt_server.pmap.pm_vers = atoi(option);
+
+ option = po_get(options, "port");
+ if (option) {
+ nfs_server.pmap.pm_port = atoi(option);
+ po_remove_all(options, "port");
+ }
+ nfs_server.pmap.pm_prog = NFS_PROGRAM;
+ option = po_get(options, "nfsprog");
+ if (option)
+ nfs_server.pmap.pm_prog = atoi(option);
+
+ option = po_get(options, "nfsvers");
+ if (option) {
+ nfs_server.pmap.pm_vers = atoi(option);
+ po_remove_all(options, "nfsvers");
+ }
+ option = po_get(options, "vers");
+ if (option) {
+ nfs_server.pmap.pm_vers = atoi(option);
+ po_remove_all(options, "vers");
+ }
+ option = po_get(options, "proto");
+ if (option) {
+ if (strcmp(option, "tcp") == 0) {
+ nfs_server.pmap.pm_prot = IPPROTO_TCP;
+ po_remove_all(options, "proto");
+ }
+ if (strcmp(option, "udp") == 0) {
+ nfs_server.pmap.pm_prot = IPPROTO_UDP;
+ po_remove_all(options, "proto");
+ }
+ }
+ p = po_rightmost(options, "tcp", "udp");
+ switch (p) {
+ case PO_KEY2_RIGHTMOST:
+ nfs_server.pmap.pm_prot = IPPROTO_UDP;
+ break;
+ case PO_KEY1_RIGHTMOST:
+ nfs_server.pmap.pm_prot = IPPROTO_TCP;
+ break;
+ }
+ po_remove_all(options, "tcp");
+ po_remove_all(options, "udp");
+
+ if (!probe_bothports(&mnt_server, &nfs_server)) {
+ rpc_mount_errors("rpcbind", 0, 0);
+ goto err;
+ }
+
+ snprintf(new_option, sizeof(new_option) - 1,
+ "nfsvers=%lu", nfs_server.pmap.pm_vers);
+ if (po_append(options, new_option) == PO_FAILED)
+ goto err;
+
+ if (nfs_server.pmap.pm_prot == IPPROTO_TCP)
+ snprintf(new_option, sizeof(new_option) - 1,
+ "proto=tcp");
+ else
+ snprintf(new_option, sizeof(new_option) - 1,
+ "proto=udp");
+ if (po_append(options, new_option) == PO_FAILED)
+ goto err;
+
+ if (nfs_server.pmap.pm_port != NFS_PORT) {
+ snprintf(new_option, sizeof(new_option) - 1,
+ "port=%lu", nfs_server.pmap.pm_port);
+ if (po_append(options, new_option) == PO_FAILED)
+ goto err;
+
+ }
+
+ return options;
+
+err:
+ po_destroy(options);
+ return NULL;
+}
+
+/*
+ * Retry an NFS mount that failed because the requested service isn't
+ * available on the server.
+ *
+ * Returns 1 if successful. Otherwise, returns zero.
+ * "errno" is set to reflect the individual error.
+ *
+ * Side effect: If the retry is successful, both 'options' and
+ * 'extra_opts' are updated to reflect the mount options that worked.
+ * If the retry fails, 'options' and 'extra_opts' are left unchanged.
+ */
+static int retry_nfsmount(const char *spec, const char *node,
+ int flags, struct mount_options *options,
+ int fake, char **extra_opts)
+{
+ struct mount_options *retry_options;
+ char *retry_str = NULL;
+
+ retry_options = rewrite_mount_options(*extra_opts);
+ if (!retry_options) {
+ errno = EIO;
+ return 0;
+ }
+
+ if (po_join(retry_options, &retry_str) == PO_FAILED) {
+ po_destroy(retry_options);
+ errno = EIO;
+ return 0;
+ }
+
+ if (verbose)
+ printf(_("%s: text-based options (retry): '%s'\n"),
+ progname, retry_str);
+
+ if (!mount(spec, node, "nfs",
+ flags & ~(MS_USER|MS_USERS), retry_str)) {
+ free(*extra_opts);
+ *extra_opts = retry_str;
+ po_replace(options, retry_options);
+ return 1;
+ }
+
+ po_destroy(retry_options);
+ free(retry_str);
+ return 0;
+}
+
+/*
+ * Attempt an NFSv2/3 mount via a mount(2) system call. If the kernel
+ * claims the requested service isn't supported on the server, probe
+ * the server to see what's supported, rewrite the mount options,
+ * and retry the request.
*
* Returns 1 if successful. Otherwise, returns zero.
* "errno" is set to reflect the individual error.
+ *
+ * Side effect: If the retry is successful, both 'options' and
+ * 'extra_opts' are updated to reflect the mount options that worked.
+ * If the retry fails, 'options' and 'extra_opts' are left unchanged.
*/
static int try_nfs23mount(const char *spec, const char *node,
int flags, struct mount_options *options,
if (!mount(spec, node, "nfs",
flags & ~(MS_USER|MS_USERS), *extra_opts))
return 1;
- return 0;
+
+ /*
+ * The kernel returns EOPNOTSUPP if the RPC bind failed,
+ * and EPROTONOSUPPORT if the version isn't supported.
+ */
+ if (errno != EOPNOTSUPP && errno != EPROTONOSUPPORT)
+ return 0;
+
+ return retry_nfsmount(spec, node, flags, options, fake, extra_opts);
}
/*
projects / nfs-utils.git / blobdiff