--- /dev/null
+/*
+ * (C) 2001 Clemson University and The University of Chicago
+ *
+ * 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>
+
+
+#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;
+}
+
+
+/*
+ * 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 *prefix,
+ 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;
+ ssize_t ret = -ENOMEM;
+ ssize_t length = 0;
+ int fsuid;
+ int fsgid;
+
+ gossip_debug(GOSSIP_XATTR_DEBUG,
+ "%s: prefix %s name %s, buffer_size %zd\n",
+ __func__, prefix, name, size);
+
+ if (name == NULL || (size > 0 && buffer == NULL)) {
+ gossip_err("orangefs_inode_getxattr: bogus NULL pointers\n");
+ return -EINVAL;
+ }
+ if ((strlen(name) + strlen(prefix)) >= ORANGEFS_MAX_XATTR_NAMELEN) {
+ gossip_err("Invalid key length (%d)\n",
+ (int)(strlen(name) + strlen(prefix)));
+ return -EINVAL;
+ }
+
+ fsuid = from_kuid(current_user_ns(), current_fsuid());
+ fsgid = from_kgid(current_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);
+
+ new_op = op_alloc(ORANGEFS_VFS_OP_GETXATTR);
+ if (!new_op)
+ goto out_unlock;
+
+ new_op->upcall.req.getxattr.refn = orangefs_inode->refn;
+ ret = snprintf((char *)new_op->upcall.req.getxattr.key,
+ ORANGEFS_MAX_XATTR_NAMELEN, "%s%s", prefix, 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 = ret + 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);
+ }
+ 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;
+ }
+
+ memset(buffer, 0, size);
+ memcpy(buffer, new_op->downcall.resp.getxattr.val, 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;
+
+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 *prefix,
+ const char *name,
+ int flags)
+{
+ struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
+ struct orangefs_kernel_op_s *new_op = NULL;
+ int ret = -ENOMEM;
+
+ 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...
+ */
+ ret = snprintf((char *)new_op->upcall.req.removexattr.key,
+ ORANGEFS_MAX_XATTR_NAMELEN,
+ "%s%s",
+ (prefix ? prefix : ""),
+ name);
+ new_op->upcall.req.removexattr.key_sz = ret + 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);
+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 *prefix,
+ 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;
+ int ret = -ENOMEM;
+
+ gossip_debug(GOSSIP_XATTR_DEBUG,
+ "%s: prefix %s, name %s, buffer_size %zd\n",
+ __func__, prefix, name, size);
+
+ if (size < 0 ||
+ size >= ORANGEFS_MAX_XATTR_VALUELEN ||
+ flags < 0) {
+ gossip_err("orangefs_inode_setxattr: bogus values of size(%d), flags(%d)\n",
+ (int)size,
+ flags);
+ return -EINVAL;
+ }
+
+ if (name == NULL ||
+ (size > 0 && value == NULL)) {
+ gossip_err("orangefs_inode_setxattr: bogus NULL pointers!\n");
+ return -EINVAL;
+ }
+
+ internal_flag = convert_to_internal_xattr_flags(flags);
+
+ if (prefix) {
+ if (strlen(name) + strlen(prefix) >= ORANGEFS_MAX_XATTR_NAMELEN) {
+ gossip_err
+ ("orangefs_inode_setxattr: bogus key size (%d)\n",
+ (int)(strlen(name) + strlen(prefix)));
+ return -EINVAL;
+ }
+ } else {
+ if (strlen(name) >= ORANGEFS_MAX_XATTR_NAMELEN) {
+ gossip_err
+ ("orangefs_inode_setxattr: bogus key size (%d)\n",
+ (int)(strlen(name)));
+ return -EINVAL;
+ }
+ }
+
+ /* This is equivalent to a removexattr */
+ if (size == 0 && value == NULL) {
+ gossip_debug(GOSSIP_XATTR_DEBUG,
+ "removing xattr (%s%s)\n",
+ prefix,
+ name);
+ return orangefs_inode_removexattr(inode, prefix, 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...
+ */
+ ret = snprintf((char *)new_op->upcall.req.setxattr.keyval.key,
+ ORANGEFS_MAX_XATTR_NAMELEN,
+ "%s%s",
+ prefix, name);
+ new_op->upcall.req.setxattr.keyval.key_sz = ret + 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);
+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 == NULL) {
+ gossip_err("%s: bogus NULL pointers\n", __func__);
+ return -EINVAL;
+ }
+ if (size < 0) {
+ gossip_err("Invalid size (%d)\n", (int)size);
+ 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 dentry *dentry,
+ const char *name,
+ const void *buffer,
+ size_t size,
+ int flags)
+{
+ return orangefs_inode_setxattr(dentry->d_inode,
+ ORANGEFS_XATTR_NAME_DEFAULT_PREFIX,
+ name,
+ buffer,
+ size,
+ flags);
+}
+
+static int orangefs_xattr_get_default(const struct xattr_handler *handler,
+ struct dentry *dentry,
+ const char *name,
+ void *buffer,
+ size_t size)
+{
+ return orangefs_inode_getxattr(dentry->d_inode,
+ ORANGEFS_XATTR_NAME_DEFAULT_PREFIX,
+ name,
+ buffer,
+ size);
+
+}
+
+static int orangefs_xattr_set_trusted(const struct xattr_handler *handler,
+ struct dentry *dentry,
+ const char *name,
+ const void *buffer,
+ size_t size,
+ int flags)
+{
+ return orangefs_inode_setxattr(dentry->d_inode,
+ ORANGEFS_XATTR_NAME_TRUSTED_PREFIX,
+ name,
+ buffer,
+ size,
+ flags);
+}
+
+static int orangefs_xattr_get_trusted(const struct xattr_handler *handler,
+ struct dentry *dentry,
+ const char *name,
+ void *buffer,
+ size_t size)
+{
+ return orangefs_inode_getxattr(dentry->d_inode,
+ ORANGEFS_XATTR_NAME_TRUSTED_PREFIX,
+ name,
+ buffer,
+ size);
+}
+
+static struct xattr_handler orangefs_xattr_trusted_handler = {
+ .prefix = ORANGEFS_XATTR_NAME_TRUSTED_PREFIX,
+ .get = orangefs_xattr_get_trusted,
+ .set = orangefs_xattr_set_trusted,
+};
+
+static struct xattr_handler orangefs_xattr_default_handler = {
+ /*
+ * NOTE: this is set to be the empty string.
+ * so that all un-prefixed xattrs keys get caught
+ * here!
+ */
+ .prefix = ORANGEFS_XATTR_NAME_DEFAULT_PREFIX,
+ .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_trusted_handler,
+ &orangefs_xattr_default_handler,
+ NULL
+};
OSDN Git Service
