]> git.decadent.org.uk Git - nfs-utils.git/blobdiff - utils/mountd/cache.c
mountd: Add lookup_export_parent()
[nfs-utils.git] / utils / mountd / cache.c
index 7d804322a2dfce0a45256dcb44d05297dce7ed5e..b858e6001ccceb2f9dbf8b4eb1aefb7375802158 100644 (file)
@@ -831,12 +831,66 @@ lookup_export(char *dom, char *path, struct addrinfo *ai)
 #include <nfs-plugin.h>
 
 /*
- * Walk through a set of FS locations and build a set of export options.
+ * Find the export entry for the parent of "pathname".
+ * Caller must not free returned exportent.
+ */
+static struct exportent *lookup_parent_export(char *dom,
+               const char *pathname, struct addrinfo *ai)
+{
+       char *parent, *slash;
+       nfs_export *result;
+
+       parent = strdup(pathname);
+       if (parent == NULL) {
+               xlog(D_GENERAL, "%s: failed to allocate parent path buffer",
+                       __func__);
+               goto out_default;
+       }
+       xlog(D_CALL, "%s: pathname = '%s'", __func__, pathname);
+
+again:
+       /* shorten pathname by one component */
+       slash = strrchr(parent, '/');
+       if (slash == NULL) {
+               xlog(D_GENERAL, "%s: no slash found in pathname",
+                       __func__);
+               goto out_default;
+       }
+       *slash = '\0';
+
+       if (strlen(parent) == 0) {
+               result = lookup_export(dom, "/", ai);
+               if (result == NULL) {
+                       xlog(L_ERROR, "%s: no root export found.", __func__);
+                       goto out_default;
+               }
+               goto out;
+       }
+
+       result = lookup_export(dom, parent, ai);
+       if (result == NULL) {
+               xlog(D_GENERAL, "%s: lookup_export(%s) found nothing",
+                       __func__, parent);
+               goto again;
+       }
+
+out:
+       xlog(D_CALL, "%s: found export for %s", __func__, parent);
+       free(parent);
+       return &result->m_export;
+
+out_default:
+       free(parent);
+       return mkexportent("*", "/", "insecure");
+}
+
+/*
+ * Walk through a set of FS locations and build an e_fslocdata string.
  * Returns true if all went to plan; otherwise, false.
  */
-static _Bool
-locations_to_options(struct jp_ops *ops, nfs_fsloc_set_t locations,
-               char *options, size_t remaining, int *ttl)
+static bool locations_to_fslocdata(struct jp_ops *ops,
+               nfs_fsloc_set_t locations, char *fslocdata,
+               size_t remaining, int *ttl)
 {
        char *server, *last_path, *rootpath, *ptr;
        _Bool seen = false;
@@ -844,7 +898,7 @@ locations_to_options(struct jp_ops *ops, nfs_fsloc_set_t locations,
        last_path = NULL;
        rootpath = NULL;
        server = NULL;
-       ptr = options;
+       ptr = fslocdata;
        *ttl = 0;
 
        for (;;) {
@@ -870,14 +924,14 @@ locations_to_options(struct jp_ops *ops, nfs_fsloc_set_t locations,
                                goto out_false;
                        }
                        if ((size_t)len >= remaining) {
-                               xlog(D_GENERAL, "%s: options buffer overflow", __func__);
+                               xlog(D_GENERAL, "%s: fslocdata buffer overflow", __func__);
                                goto out_false;
                        }
                        remaining -= (size_t)len;
                        ptr += len;
                } else {
                        if (last_path == NULL)
-                               len = snprintf(ptr, remaining, "refer=%s@%s",
+                               len = snprintf(ptr, remaining, "%s@%s",
                                                        rootpath, server);
                        else
                                len = snprintf(ptr, remaining, ":%s@%s",
@@ -887,7 +941,7 @@ locations_to_options(struct jp_ops *ops, nfs_fsloc_set_t locations,
                                goto out_false;
                        }
                        if ((size_t)len >= remaining) {
-                               xlog(D_GENERAL, "%s: options buffer overflow",
+                               xlog(D_GENERAL, "%s: fslocdata buffer overflow",
                                        __func__);
                                goto out_false;
                        }
@@ -901,8 +955,8 @@ locations_to_options(struct jp_ops *ops, nfs_fsloc_set_t locations,
                free(server);
        }
 
-       xlog(D_CALL, "%s: options='%s', ttl=%d",
-               __func__, options, *ttl);
+       xlog(D_CALL, "%s: fslocdata='%s', ttl=%d",
+               __func__, fslocdata, *ttl);
        return seen;
 
 out_false:
@@ -917,17 +971,20 @@ out_false:
  *
  * Returned exportent points to static memory.
  */
-static struct exportent *do_locations_to_export(struct jp_ops *ops,
+static struct exportent *locations_to_export(struct jp_ops *ops,
                nfs_fsloc_set_t locations, const char *junction,
-               char *options, size_t options_len)
+               struct exportent *UNUSED(parent))
 {
+       static char fslocdata[BUFSIZ];
        struct exportent *exp;
        int ttl;
 
-       if (!locations_to_options(ops, locations, options, options_len, &ttl))
+       fslocdata[0] = '\0';
+       if (!locations_to_fslocdata(ops, locations,
+                                       fslocdata, sizeof(fslocdata), &ttl))
                return NULL;
 
-       exp = mkexportent("*", (char *)junction, options);
+       exp = mkexportent("*", (char *)junction, "");
        if (exp == NULL) {
                xlog(L_ERROR, "%s: Failed to construct exportent", __func__);
                return NULL;
@@ -935,33 +992,14 @@ static struct exportent *do_locations_to_export(struct jp_ops *ops,
 
        exp->e_uuid = NULL;
        exp->e_ttl = ttl;
-       return exp;
-}
 
-/*
- * Convert set of FS locations to an exportent.  Returns pointer to
- * an exportent if "junction" refers to a junction.
- *
- * Returned exportent points to static memory.
- */
-static struct exportent *locations_to_export(struct jp_ops *ops,
-               nfs_fsloc_set_t locations, const char *junction)
-{
-       struct exportent *exp;
-       char *options;
-
-       options = malloc(BUFSIZ);
-       if (options == NULL) {
-               xlog(D_GENERAL, "%s: failed to allocate options buffer",
-                       __func__);
+       free(exp->e_fslocdata);
+       exp->e_fslocmethod = FSLOC_REFER;
+       exp->e_fslocdata = strdup(fslocdata);
+       if (exp->e_fslocdata == NULL) {
+               xlog(L_ERROR, "%s: No memory", __func__);
                return NULL;
        }
-       options[0] = '\0';
-
-       exp = do_locations_to_export(ops, locations, junction,
-                                               options, BUFSIZ);
-
-       free(options);
        return exp;
 }
 
@@ -972,11 +1010,11 @@ static struct exportent *locations_to_export(struct jp_ops *ops,
  *
  * Returned exportent points to static memory.
  */
-static struct exportent *invoke_junction_ops(void *handle,
-               const char *junction)
+static struct exportent *invoke_junction_ops(void *handle, char *dom,
+               const char *junction, struct addrinfo *ai)
 {
+       struct exportent *parent, *exp = NULL;
        nfs_fsloc_set_t locations;
-       struct exportent *exp;
        enum jp_status status;
        struct jp_ops *ops;
        char *error;
@@ -1002,15 +1040,28 @@ static struct exportent *invoke_junction_ops(void *handle,
        }
 
        status = ops->jp_get_locations(junction, &locations);
-       if (status != JP_OK) {
-               xlog(D_GENERAL, "%s: failed to resolve %s: %s",
-                       __func__, junction, ops->jp_error(status));
-               return NULL;
+       switch (status) {
+       case JP_OK:
+               break;
+       case JP_NOTJUNCTION:
+               xlog(D_GENERAL, "%s: %s is not a junction",
+                       __func__, junction);
+               goto out;
+       default:
+               xlog(L_WARNING, "Dangling junction %s: %s",
+                       junction, ops->jp_error(status));
+               goto out;
        }
 
-       exp = locations_to_export(ops, locations, junction);
+       parent = lookup_parent_export(dom, junction, ai);
+       if (parent == NULL)
+               goto out;
+
+       exp = locations_to_export(ops, locations, junction, parent);
 
        ops->jp_put_locations(locations);
+
+out:
        ops->jp_done();
        return exp;
 }
@@ -1022,7 +1073,8 @@ static struct exportent *invoke_junction_ops(void *handle,
  *
  * Returned exportent points to static memory.
  */
-static struct exportent *lookup_junction(const char *pathname)
+static struct exportent *lookup_junction(char *dom, const char *pathname,
+               struct addrinfo *ai)
 {
        struct exportent *exp;
        void *handle;
@@ -1034,7 +1086,7 @@ static struct exportent *lookup_junction(const char *pathname)
        }
        (void)dlerror();        /* Clear any error */
 
-       exp = invoke_junction_ops(handle, pathname);
+       exp = invoke_junction_ops(handle, dom, pathname, ai);
 
        /* We could leave it loaded to make junction resolution
         * faster next time.  However, if we want to replace the
@@ -1043,7 +1095,8 @@ static struct exportent *lookup_junction(const char *pathname)
        return exp;
 }
 #else  /* !HAVE_NFS_PLUGIN_H */
-static inline struct exportent *lookup_junction(const char *UNUSED(pathname))
+static inline struct exportent *lookup_junction(char *UNUSED(dom),
+               const char *UNUSED(pathname), struct addrinfo *UNUSED(ai))
 {
        return NULL;
 }
@@ -1097,7 +1150,7 @@ static void nfsd_export(FILE *f)
                        dump_to_cache(f, dom, path, NULL);
                }
        } else {
-               dump_to_cache(f, dom, path, lookup_junction(path));
+               dump_to_cache(f, dom, path, lookup_junction(dom, path, ai));
        }
  out:
        xlog(D_CALL, "nfsd_export: found %p path %s", found, path ? path : NULL);