/* * Copyright (C) 2008 Christoph Hellwig. * Portions Copyright (C) 2000-2008 Silicon Graphics, Inc. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation. * * This program is distributed in the hope that it would be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ #include "xfs.h" #include "xfs_format.h" #include "xfs_log_format.h" #include "xfs_trans_resv.h" #include "xfs_mount.h" #include "xfs_da_format.h" #include "xfs_inode.h" #include "xfs_attr.h" #include "xfs_attr_leaf.h" #include "xfs_acl.h" #include #include static int xfs_xattr_get(const struct xattr_handler *handler, struct dentry *dentry, const char *name, void *value, size_t size) { int xflags = handler->flags; struct xfs_inode *ip = XFS_I(d_inode(dentry)); int error, asize = size; /* Convert Linux syscall to XFS internal ATTR flags */ if (!size) { xflags |= ATTR_KERNOVAL; value = NULL; } error = xfs_attr_get(ip, (unsigned char *)name, value, &asize, xflags); if (error) return error; return asize; } void xfs_forget_acl( struct inode *inode, const char *name, int xflags) { /* * Invalidate any cached ACLs if the user has bypassed the ACL * interface. We don't validate the content whatsoever so it is caller * responsibility to provide data in valid format and ensure i_mode is * consistent. */ if (xflags & ATTR_ROOT) { #ifdef CONFIG_XFS_POSIX_ACL if (!strcmp(name, SGI_ACL_FILE)) forget_cached_acl(inode, ACL_TYPE_ACCESS); else if (!strcmp(name, SGI_ACL_DEFAULT)) forget_cached_acl(inode, ACL_TYPE_DEFAULT); #endif } } static int xfs_xattr_set(const struct xattr_handler *handler, struct dentry *dentry, const char *name, const void *value, size_t size, int flags) { int xflags = handler->flags; struct xfs_inode *ip = XFS_I(d_inode(dentry)); int error; /* Convert Linux syscall to XFS internal ATTR flags */ if (flags & XATTR_CREATE) xflags |= ATTR_CREATE; if (flags & XATTR_REPLACE) xflags |= ATTR_REPLACE; if (!value) return xfs_attr_remove(ip, (unsigned char *)name, xflags); error = xfs_attr_set(ip, (unsigned char *)name, (void *)value, size, xflags); if (!error) xfs_forget_acl(d_inode(dentry), name, xflags); return error; } static const struct xattr_handler xfs_xattr_user_handler = { .prefix = XATTR_USER_PREFIX, .flags = 0, /* no flags implies user namespace */ .get = xfs_xattr_get, .set = xfs_xattr_set, }; static const struct xattr_handler xfs_xattr_trusted_handler = { .prefix = XATTR_TRUSTED_PREFIX, .flags = ATTR_ROOT, .get = xfs_xattr_get, .set = xfs_xattr_set, }; static const struct xattr_handler xfs_xattr_security_handler = { .prefix = XATTR_SECURITY_PREFIX, .flags = ATTR_SECURE, .get = xfs_xattr_get, .set = xfs_xattr_set, }; const struct xattr_handler *xfs_xattr_handlers[] = { &xfs_xattr_user_handler, &xfs_xattr_trusted_handler, &xfs_xattr_security_handler, #ifdef CONFIG_XFS_POSIX_ACL &posix_acl_access_xattr_handler, &posix_acl_default_xattr_handler, #endif NULL }; static int __xfs_xattr_put_listent( struct xfs_attr_list_context *context, char *prefix, int prefix_len, unsigned char *name, int namelen) { char *offset; int arraytop; if (!context->alist) goto compute_size; arraytop = context->count + prefix_len + namelen + 1; if (arraytop > context->firstu) { context->count = -1; /* insufficient space */ return 1; } offset = (char *)context->alist + context->count; strncpy(offset, prefix, prefix_len); offset += prefix_len; strncpy(offset, (char *)name, namelen); /* real name */ offset += namelen; *offset = '\0'; compute_size: context->count += prefix_len + namelen + 1; return 0; } static int xfs_xattr_put_listent( struct xfs_attr_list_context *context, int flags, unsigned char *name, int namelen, int valuelen, unsigned char *value) { char *prefix; int prefix_len; ASSERT(context->count >= 0); if (flags & XFS_ATTR_ROOT) { #ifdef CONFIG_XFS_POSIX_ACL if (namelen == SGI_ACL_FILE_SIZE && strncmp(name, SGI_ACL_FILE, SGI_ACL_FILE_SIZE) == 0) { int ret = __xfs_xattr_put_listent( context, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN, XATTR_POSIX_ACL_ACCESS, strlen(XATTR_POSIX_ACL_ACCESS)); if (ret) return ret; } else if (namelen == SGI_ACL_DEFAULT_SIZE && strncmp(name, SGI_ACL_DEFAULT, SGI_ACL_DEFAULT_SIZE) == 0) { int ret = __xfs_xattr_put_listent( context, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN, XATTR_POSIX_ACL_DEFAULT, strlen(XATTR_POSIX_ACL_DEFAULT)); if (ret) return ret; } #endif /* * Only show root namespace entries if we are actually allowed to * see them. */ if (!capable(CAP_SYS_ADMIN)) return 0; prefix = XATTR_TRUSTED_PREFIX; prefix_len = XATTR_TRUSTED_PREFIX_LEN; } else if (flags & XFS_ATTR_SECURE) { prefix = XATTR_SECURITY_PREFIX; prefix_len = XATTR_SECURITY_PREFIX_LEN; } else { prefix = XATTR_USER_PREFIX; prefix_len = XATTR_USER_PREFIX_LEN; } return __xfs_xattr_put_listent(context, prefix, prefix_len, name, namelen); } ssize_t xfs_vn_listxattr(struct dentry *dentry, char *data, size_t size) { struct xfs_attr_list_context context; struct attrlist_cursor_kern cursor = { 0 }; struct inode *inode = d_inode(dentry); /* * First read the regular on-disk attributes. */ memset(&context, 0, sizeof(context)); context.dp = XFS_I(inode); context.cursor = &cursor; context.resynch = 1; context.alist = size ? data : NULL; context.bufsize = size; context.firstu = context.bufsize; context.put_listent = xfs_xattr_put_listent; xfs_attr_list_int(&context); if (context.count < 0) return -ERANGE; return context.count; }