/* * (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 *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: 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); 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); } 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; 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; 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); 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; 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); 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 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 };