summaryrefslogtreecommitdiffstats
path: root/fs/orangefs/xattr.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/orangefs/xattr.c')
-rw-r--r--fs/orangefs/xattr.c562
1 files changed, 562 insertions, 0 deletions
diff --git a/fs/orangefs/xattr.c b/fs/orangefs/xattr.c
new file mode 100644
index 000000000..9a5b757fb
--- /dev/null
+++ b/fs/orangefs/xattr.c
@@ -0,0 +1,562 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * (C) 2001 Clemson University and The University of Chicago
+ * Copyright 2018 Omnibond Systems, L.L.C.
+ *
+ * See COPYING in top-level directory.
+ */
+
+/*
+ * Linux VFS extended attribute operations.
+ */
+
+#include "protocol.h"
+#include "orangefs-kernel.h"
+#include "orangefs-bufmap.h"
+#include <linux/posix_acl_xattr.h>
+#include <linux/xattr.h>
+#include <linux/hashtable.h>
+
+#define SYSTEM_ORANGEFS_KEY "system.pvfs2."
+#define SYSTEM_ORANGEFS_KEY_LEN 13
+
+/*
+ * this function returns
+ * 0 if the key corresponding to name is not meant to be printed as part
+ * of a listxattr.
+ * 1 if the key corresponding to name is meant to be returned as part of
+ * a listxattr.
+ * The ones that start SYSTEM_ORANGEFS_KEY are the ones to avoid printing.
+ */
+static int is_reserved_key(const char *key, size_t size)
+{
+
+ if (size < SYSTEM_ORANGEFS_KEY_LEN)
+ return 1;
+
+ return strncmp(key, SYSTEM_ORANGEFS_KEY, SYSTEM_ORANGEFS_KEY_LEN) ? 1 : 0;
+}
+
+static inline int convert_to_internal_xattr_flags(int setxattr_flags)
+{
+ int internal_flag = 0;
+
+ if (setxattr_flags & XATTR_REPLACE) {
+ /* Attribute must exist! */
+ internal_flag = ORANGEFS_XATTR_REPLACE;
+ } else if (setxattr_flags & XATTR_CREATE) {
+ /* Attribute must not exist */
+ internal_flag = ORANGEFS_XATTR_CREATE;
+ }
+ return internal_flag;
+}
+
+static unsigned int xattr_key(const char *key)
+{
+ unsigned int i = 0;
+ while (key)
+ i += *key++;
+ return i % 16;
+}
+
+static struct orangefs_cached_xattr *find_cached_xattr(struct inode *inode,
+ const char *key)
+{
+ struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
+ struct orangefs_cached_xattr *cx;
+ struct hlist_head *h;
+ struct hlist_node *tmp;
+ h = &orangefs_inode->xattr_cache[xattr_key(key)];
+ if (hlist_empty(h))
+ return NULL;
+ hlist_for_each_entry_safe(cx, tmp, h, node) {
+/* if (!time_before(jiffies, cx->timeout)) {
+ hlist_del(&cx->node);
+ kfree(cx);
+ continue;
+ }*/
+ if (!strcmp(cx->key, key))
+ return cx;
+ }
+ return NULL;
+}
+
+/*
+ * Tries to get a specified key's attributes of a given
+ * file into a user-specified buffer. Note that the getxattr
+ * interface allows for the users to probe the size of an
+ * extended attribute by passing in a value of 0 to size.
+ * Thus our return value is always the size of the attribute
+ * unless the key does not exist for the file and/or if
+ * there were errors in fetching the attribute value.
+ */
+ssize_t orangefs_inode_getxattr(struct inode *inode, const char *name,
+ void *buffer, size_t size)
+{
+ struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
+ struct orangefs_kernel_op_s *new_op = NULL;
+ struct orangefs_cached_xattr *cx;
+ ssize_t ret = -ENOMEM;
+ ssize_t length = 0;
+ int fsuid;
+ int fsgid;
+
+ gossip_debug(GOSSIP_XATTR_DEBUG,
+ "%s: name %s, buffer_size %zd\n",
+ __func__, name, size);
+
+ if (S_ISLNK(inode->i_mode))
+ return -EOPNOTSUPP;
+
+ if (strlen(name) >= ORANGEFS_MAX_XATTR_NAMELEN)
+ return -EINVAL;
+
+ fsuid = from_kuid(&init_user_ns, current_fsuid());
+ fsgid = from_kgid(&init_user_ns, current_fsgid());
+
+ gossip_debug(GOSSIP_XATTR_DEBUG,
+ "getxattr on inode %pU, name %s "
+ "(uid %o, gid %o)\n",
+ get_khandle_from_ino(inode),
+ name,
+ fsuid,
+ fsgid);
+
+ down_read(&orangefs_inode->xattr_sem);
+
+ cx = find_cached_xattr(inode, name);
+ if (cx && time_before(jiffies, cx->timeout)) {
+ if (cx->length == -1) {
+ ret = -ENODATA;
+ goto out_unlock;
+ } else {
+ if (size == 0) {
+ ret = cx->length;
+ goto out_unlock;
+ }
+ if (cx->length > size) {
+ ret = -ERANGE;
+ goto out_unlock;
+ }
+ memcpy(buffer, cx->val, cx->length);
+ memset(buffer + cx->length, 0, size - cx->length);
+ ret = cx->length;
+ goto out_unlock;
+ }
+ }
+
+ new_op = op_alloc(ORANGEFS_VFS_OP_GETXATTR);
+ if (!new_op)
+ goto out_unlock;
+
+ new_op->upcall.req.getxattr.refn = orangefs_inode->refn;
+ strcpy(new_op->upcall.req.getxattr.key, name);
+
+ /*
+ * NOTE: Although keys are meant to be NULL terminated textual
+ * strings, I am going to explicitly pass the length just in case
+ * we change this later on...
+ */
+ new_op->upcall.req.getxattr.key_sz = strlen(name) + 1;
+
+ ret = service_operation(new_op, "orangefs_inode_getxattr",
+ get_interruptible_flag(inode));
+ if (ret != 0) {
+ if (ret == -ENOENT) {
+ ret = -ENODATA;
+ gossip_debug(GOSSIP_XATTR_DEBUG,
+ "orangefs_inode_getxattr: inode %pU key %s"
+ " does not exist!\n",
+ get_khandle_from_ino(inode),
+ (char *)new_op->upcall.req.getxattr.key);
+ cx = kmalloc(sizeof *cx, GFP_KERNEL);
+ if (cx) {
+ strcpy(cx->key, name);
+ cx->length = -1;
+ cx->timeout = jiffies +
+ orangefs_getattr_timeout_msecs*HZ/1000;
+ hash_add(orangefs_inode->xattr_cache, &cx->node,
+ xattr_key(cx->key));
+ }
+ }
+ goto out_release_op;
+ }
+
+ /*
+ * Length returned includes null terminator.
+ */
+ length = new_op->downcall.resp.getxattr.val_sz;
+
+ /*
+ * Just return the length of the queried attribute.
+ */
+ if (size == 0) {
+ ret = length;
+ goto out_release_op;
+ }
+
+ /*
+ * Check to see if key length is > provided buffer size.
+ */
+ if (length > size) {
+ ret = -ERANGE;
+ goto out_release_op;
+ }
+
+ memcpy(buffer, new_op->downcall.resp.getxattr.val, length);
+ memset(buffer + length, 0, size - length);
+ gossip_debug(GOSSIP_XATTR_DEBUG,
+ "orangefs_inode_getxattr: inode %pU "
+ "key %s key_sz %d, val_len %d\n",
+ get_khandle_from_ino(inode),
+ (char *)new_op->
+ upcall.req.getxattr.key,
+ (int)new_op->
+ upcall.req.getxattr.key_sz,
+ (int)ret);
+
+ ret = length;
+
+ if (cx) {
+ strcpy(cx->key, name);
+ memcpy(cx->val, buffer, length);
+ cx->length = length;
+ cx->timeout = jiffies + HZ;
+ } else {
+ cx = kmalloc(sizeof *cx, GFP_KERNEL);
+ if (cx) {
+ strcpy(cx->key, name);
+ memcpy(cx->val, buffer, length);
+ cx->length = length;
+ cx->timeout = jiffies + HZ;
+ hash_add(orangefs_inode->xattr_cache, &cx->node,
+ xattr_key(cx->key));
+ }
+ }
+
+out_release_op:
+ op_release(new_op);
+out_unlock:
+ up_read(&orangefs_inode->xattr_sem);
+ return ret;
+}
+
+static int orangefs_inode_removexattr(struct inode *inode, const char *name,
+ int flags)
+{
+ struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
+ struct orangefs_kernel_op_s *new_op = NULL;
+ struct orangefs_cached_xattr *cx;
+ struct hlist_head *h;
+ struct hlist_node *tmp;
+ int ret = -ENOMEM;
+
+ if (strlen(name) >= ORANGEFS_MAX_XATTR_NAMELEN)
+ return -EINVAL;
+
+ down_write(&orangefs_inode->xattr_sem);
+ new_op = op_alloc(ORANGEFS_VFS_OP_REMOVEXATTR);
+ if (!new_op)
+ goto out_unlock;
+
+ new_op->upcall.req.removexattr.refn = orangefs_inode->refn;
+ /*
+ * NOTE: Although keys are meant to be NULL terminated
+ * textual strings, I am going to explicitly pass the
+ * length just in case we change this later on...
+ */
+ strcpy(new_op->upcall.req.removexattr.key, name);
+ new_op->upcall.req.removexattr.key_sz = strlen(name) + 1;
+
+ gossip_debug(GOSSIP_XATTR_DEBUG,
+ "orangefs_inode_removexattr: key %s, key_sz %d\n",
+ (char *)new_op->upcall.req.removexattr.key,
+ (int)new_op->upcall.req.removexattr.key_sz);
+
+ ret = service_operation(new_op,
+ "orangefs_inode_removexattr",
+ get_interruptible_flag(inode));
+ if (ret == -ENOENT) {
+ /*
+ * Request to replace a non-existent attribute is an error.
+ */
+ if (flags & XATTR_REPLACE)
+ ret = -ENODATA;
+ else
+ ret = 0;
+ }
+
+ gossip_debug(GOSSIP_XATTR_DEBUG,
+ "orangefs_inode_removexattr: returning %d\n", ret);
+
+ op_release(new_op);
+
+ h = &orangefs_inode->xattr_cache[xattr_key(name)];
+ hlist_for_each_entry_safe(cx, tmp, h, node) {
+ if (!strcmp(cx->key, name)) {
+ hlist_del(&cx->node);
+ kfree(cx);
+ break;
+ }
+ }
+
+out_unlock:
+ up_write(&orangefs_inode->xattr_sem);
+ return ret;
+}
+
+/*
+ * Tries to set an attribute for a given key on a file.
+ *
+ * Returns a -ve number on error and 0 on success. Key is text, but value
+ * can be binary!
+ */
+int orangefs_inode_setxattr(struct inode *inode, const char *name,
+ const void *value, size_t size, int flags)
+{
+ struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
+ struct orangefs_kernel_op_s *new_op;
+ int internal_flag = 0;
+ struct orangefs_cached_xattr *cx;
+ struct hlist_head *h;
+ struct hlist_node *tmp;
+ int ret = -ENOMEM;
+
+ gossip_debug(GOSSIP_XATTR_DEBUG,
+ "%s: name %s, buffer_size %zd\n",
+ __func__, name, size);
+
+ if (size > ORANGEFS_MAX_XATTR_VALUELEN)
+ return -EINVAL;
+ if (strlen(name) >= ORANGEFS_MAX_XATTR_NAMELEN)
+ return -EINVAL;
+
+ internal_flag = convert_to_internal_xattr_flags(flags);
+
+ /* This is equivalent to a removexattr */
+ if (size == 0 && !value) {
+ gossip_debug(GOSSIP_XATTR_DEBUG,
+ "removing xattr (%s)\n",
+ name);
+ return orangefs_inode_removexattr(inode, name, flags);
+ }
+
+ gossip_debug(GOSSIP_XATTR_DEBUG,
+ "setxattr on inode %pU, name %s\n",
+ get_khandle_from_ino(inode),
+ name);
+
+ down_write(&orangefs_inode->xattr_sem);
+ new_op = op_alloc(ORANGEFS_VFS_OP_SETXATTR);
+ if (!new_op)
+ goto out_unlock;
+
+
+ new_op->upcall.req.setxattr.refn = orangefs_inode->refn;
+ new_op->upcall.req.setxattr.flags = internal_flag;
+ /*
+ * NOTE: Although keys are meant to be NULL terminated textual
+ * strings, I am going to explicitly pass the length just in
+ * case we change this later on...
+ */
+ strcpy(new_op->upcall.req.setxattr.keyval.key, name);
+ new_op->upcall.req.setxattr.keyval.key_sz = strlen(name) + 1;
+ memcpy(new_op->upcall.req.setxattr.keyval.val, value, size);
+ new_op->upcall.req.setxattr.keyval.val_sz = size;
+
+ gossip_debug(GOSSIP_XATTR_DEBUG,
+ "orangefs_inode_setxattr: key %s, key_sz %d "
+ " value size %zd\n",
+ (char *)new_op->upcall.req.setxattr.keyval.key,
+ (int)new_op->upcall.req.setxattr.keyval.key_sz,
+ size);
+
+ ret = service_operation(new_op,
+ "orangefs_inode_setxattr",
+ get_interruptible_flag(inode));
+
+ gossip_debug(GOSSIP_XATTR_DEBUG,
+ "orangefs_inode_setxattr: returning %d\n",
+ ret);
+
+ /* when request is serviced properly, free req op struct */
+ op_release(new_op);
+
+ h = &orangefs_inode->xattr_cache[xattr_key(name)];
+ hlist_for_each_entry_safe(cx, tmp, h, node) {
+ if (!strcmp(cx->key, name)) {
+ hlist_del(&cx->node);
+ kfree(cx);
+ break;
+ }
+ }
+
+out_unlock:
+ up_write(&orangefs_inode->xattr_sem);
+ return ret;
+}
+
+/*
+ * Tries to get a specified object's keys into a user-specified buffer of a
+ * given size. Note that like the previous instances of xattr routines, this
+ * also allows you to pass in a NULL pointer and 0 size to probe the size for
+ * subsequent memory allocations. Thus our return value is always the size of
+ * all the keys unless there were errors in fetching the keys!
+ */
+ssize_t orangefs_listxattr(struct dentry *dentry, char *buffer, size_t size)
+{
+ struct inode *inode = dentry->d_inode;
+ struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
+ struct orangefs_kernel_op_s *new_op;
+ __u64 token = ORANGEFS_ITERATE_START;
+ ssize_t ret = -ENOMEM;
+ ssize_t total = 0;
+ int count_keys = 0;
+ int key_size;
+ int i = 0;
+ int returned_count = 0;
+
+ if (size > 0 && !buffer) {
+ gossip_err("%s: bogus NULL pointers\n", __func__);
+ return -EINVAL;
+ }
+
+ down_read(&orangefs_inode->xattr_sem);
+ new_op = op_alloc(ORANGEFS_VFS_OP_LISTXATTR);
+ if (!new_op)
+ goto out_unlock;
+
+ if (buffer && size > 0)
+ memset(buffer, 0, size);
+
+try_again:
+ key_size = 0;
+ new_op->upcall.req.listxattr.refn = orangefs_inode->refn;
+ new_op->upcall.req.listxattr.token = token;
+ new_op->upcall.req.listxattr.requested_count =
+ (size == 0) ? 0 : ORANGEFS_MAX_XATTR_LISTLEN;
+ ret = service_operation(new_op, __func__,
+ get_interruptible_flag(inode));
+ if (ret != 0)
+ goto done;
+
+ if (size == 0) {
+ /*
+ * This is a bit of a big upper limit, but I did not want to
+ * spend too much time getting this correct, since users end
+ * up allocating memory rather than us...
+ */
+ total = new_op->downcall.resp.listxattr.returned_count *
+ ORANGEFS_MAX_XATTR_NAMELEN;
+ goto done;
+ }
+
+ returned_count = new_op->downcall.resp.listxattr.returned_count;
+ if (returned_count < 0 ||
+ returned_count > ORANGEFS_MAX_XATTR_LISTLEN) {
+ gossip_err("%s: impossible value for returned_count:%d:\n",
+ __func__,
+ returned_count);
+ ret = -EIO;
+ goto done;
+ }
+
+ /*
+ * Check to see how much can be fit in the buffer. Fit only whole keys.
+ */
+ for (i = 0; i < returned_count; i++) {
+ if (new_op->downcall.resp.listxattr.lengths[i] < 0 ||
+ new_op->downcall.resp.listxattr.lengths[i] >
+ ORANGEFS_MAX_XATTR_NAMELEN) {
+ gossip_err("%s: impossible value for lengths[%d]\n",
+ __func__,
+ new_op->downcall.resp.listxattr.lengths[i]);
+ ret = -EIO;
+ goto done;
+ }
+ if (total + new_op->downcall.resp.listxattr.lengths[i] > size)
+ goto done;
+
+ /*
+ * Since many dumb programs try to setxattr() on our reserved
+ * xattrs this is a feeble attempt at defeating those by not
+ * listing them in the output of listxattr.. sigh
+ */
+ if (is_reserved_key(new_op->downcall.resp.listxattr.key +
+ key_size,
+ new_op->downcall.resp.
+ listxattr.lengths[i])) {
+ gossip_debug(GOSSIP_XATTR_DEBUG, "Copying key %d -> %s\n",
+ i, new_op->downcall.resp.listxattr.key +
+ key_size);
+ memcpy(buffer + total,
+ new_op->downcall.resp.listxattr.key + key_size,
+ new_op->downcall.resp.listxattr.lengths[i]);
+ total += new_op->downcall.resp.listxattr.lengths[i];
+ count_keys++;
+ } else {
+ gossip_debug(GOSSIP_XATTR_DEBUG, "[RESERVED] key %d -> %s\n",
+ i, new_op->downcall.resp.listxattr.key +
+ key_size);
+ }
+ key_size += new_op->downcall.resp.listxattr.lengths[i];
+ }
+
+ /*
+ * Since the buffer was large enough, we might have to continue
+ * fetching more keys!
+ */
+ token = new_op->downcall.resp.listxattr.token;
+ if (token != ORANGEFS_ITERATE_END)
+ goto try_again;
+
+done:
+ gossip_debug(GOSSIP_XATTR_DEBUG, "%s: returning %d"
+ " [size of buffer %ld] (filled in %d keys)\n",
+ __func__,
+ ret ? (int)ret : (int)total,
+ (long)size,
+ count_keys);
+ op_release(new_op);
+ if (ret == 0)
+ ret = total;
+out_unlock:
+ up_read(&orangefs_inode->xattr_sem);
+ return ret;
+}
+
+static int orangefs_xattr_set_default(const struct xattr_handler *handler,
+ struct user_namespace *mnt_userns,
+ struct dentry *unused,
+ struct inode *inode,
+ const char *name,
+ const void *buffer,
+ size_t size,
+ int flags)
+{
+ return orangefs_inode_setxattr(inode, name, buffer, size, flags);
+}
+
+static int orangefs_xattr_get_default(const struct xattr_handler *handler,
+ struct dentry *unused,
+ struct inode *inode,
+ const char *name,
+ void *buffer,
+ size_t size)
+{
+ return orangefs_inode_getxattr(inode, name, buffer, size);
+
+}
+
+static const struct xattr_handler orangefs_xattr_default_handler = {
+ .prefix = "", /* match any name => handlers called with full name */
+ .get = orangefs_xattr_get_default,
+ .set = orangefs_xattr_set_default,
+};
+
+const struct xattr_handler *orangefs_xattr_handlers[] = {
+ &posix_acl_access_xattr_handler,
+ &posix_acl_default_xattr_handler,
+ &orangefs_xattr_default_handler,
+ NULL
+};