Return-Path: Received: from mail-wg0-f51.google.com ([74.125.82.51]:33211 "EHLO mail-wg0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964984AbbDXLFf (ORCPT ); Fri, 24 Apr 2015 07:05:35 -0400 From: Andreas Gruenbacher To: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-nfs@vger.kernel.org Subject: [RFC v3 31/45] richacl: Create acl with masks applied in richacl_from_mode() Date: Fri, 24 Apr 2015 13:04:28 +0200 Message-Id: <465fc03eef5cf40890c7366a01ff219fdead8ff5.1429868795.git.agruenba@redhat.com> In-Reply-To: References: In-Reply-To: References: Sender: linux-nfs-owner@vger.kernel.org List-ID: When creating a richacl that represents a particular file mode, one approach is to create one everyone@ allow entry and set the richacl masks according to the file mode; when those masks are applied with richacl_apply_masks(), that everyone@ allow entry gets transformed as needed. The other approach is to compute the result after richacl_apply_masks() directly; this commit does that. Signed-off-by: Andreas Gruenbacher --- fs/richacl_compat.c | 85 ++++++++++++++++++++++++++++++++++++++++++----------- 1 file changed, 68 insertions(+), 17 deletions(-) diff --git a/fs/richacl_compat.c b/fs/richacl_compat.c index 8ebe772..33fc50c 100644 --- a/fs/richacl_compat.c +++ b/fs/richacl_compat.c @@ -761,30 +761,81 @@ EXPORT_SYMBOL_GPL(richacl_apply_masks); struct richacl * richacl_from_mode_unmasked(mode_t mode) { + unsigned int owner_mask = richacl_mode_to_mask(mode >> 6) | + RICHACE_POSIX_OWNER_ALLOWED; + unsigned int group_mask = richacl_mode_to_mask(mode >> 3); + unsigned int other_mask = richacl_mode_to_mask(mode); + unsigned int denied; + unsigned int entries = 0; struct richacl *acl; struct richace *ace; - acl = richacl_alloc(1, GFP_KERNEL); + /* RICHACE_DELETE_CHILD is meaningless for non-directories. */ + if (!S_ISDIR(mode)) { + owner_mask &= ~RICHACE_DELETE_CHILD; + group_mask &= ~RICHACE_DELETE_CHILD; + other_mask &= ~RICHACE_DELETE_CHILD; + } + + if (owner_mask & ~(group_mask & other_mask)) + entries++; /* OWNER@ ALLOW entry needed */ + denied = ~owner_mask & (group_mask | other_mask); + if (denied) + entries++; /* OWNER@ DENY entry needed */ + if (group_mask & ~other_mask) + entries++; /* GROUP@ ALLOW entry needed */ + denied = ~group_mask & other_mask; + if (denied) + entries++; /* GROUP@ DENY entry needed */ + if (other_mask) + entries++; /* EVERYONE@ ALLOW entry needed */ + + acl = richacl_alloc(entries, GFP_KERNEL); if (!acl) return NULL; - acl->a_flags = RICHACL_MASKED; - acl->a_owner_mask = richacl_mode_to_mask(mode >> 6) | - RICHACE_POSIX_OWNER_ALLOWED; - acl->a_group_mask = richacl_mode_to_mask(mode >> 3); - acl->a_other_mask = richacl_mode_to_mask(mode); - + acl->a_owner_mask = owner_mask; + acl->a_group_mask = group_mask; + acl->a_other_mask = other_mask; ace = acl->a_entries; - ace->e_type = RICHACE_ACCESS_ALLOWED_ACE_TYPE; - ace->e_flags = RICHACE_SPECIAL_WHO; - ace->e_mask = RICHACE_POSIX_ALWAYS_ALLOWED | - RICHACE_POSIX_MODE_ALL | - RICHACE_POSIX_OWNER_ALLOWED; - /* RICHACE_DELETE_CHILD is meaningless for non-directories. */ - if (!S_ISDIR(mode)) - ace->e_mask &= ~RICHACE_DELETE_CHILD; - ace->e_id.special = RICHACE_EVERYONE_SPECIAL_ID; - return acl; + if (owner_mask & ~(group_mask & other_mask)) { + ace->e_type = RICHACE_ACCESS_ALLOWED_ACE_TYPE; + ace->e_flags = RICHACE_SPECIAL_WHO; + ace->e_mask = owner_mask; + ace->e_id.special = RICHACE_OWNER_SPECIAL_ID; + ace++; + } + denied = ~owner_mask & (group_mask | other_mask); + if (denied) { + ace->e_type = RICHACE_ACCESS_DENIED_ACE_TYPE; + ace->e_flags = RICHACE_SPECIAL_WHO; + ace->e_mask = denied; + ace->e_id.special = RICHACE_OWNER_SPECIAL_ID; + ace++; + } + if (group_mask & ~other_mask) { + ace->e_type = RICHACE_ACCESS_ALLOWED_ACE_TYPE; + ace->e_flags = RICHACE_SPECIAL_WHO; + ace->e_mask = group_mask; + ace->e_id.special = RICHACE_GROUP_SPECIAL_ID; + ace++; + } + denied = ~group_mask & other_mask; + if (denied) { + ace->e_type = RICHACE_ACCESS_DENIED_ACE_TYPE; + ace->e_flags = RICHACE_SPECIAL_WHO; + ace->e_mask = denied; + ace->e_id.special = RICHACE_GROUP_SPECIAL_ID; + ace++; + } + if (other_mask) { + ace->e_type = RICHACE_ACCESS_ALLOWED_ACE_TYPE; + ace->e_flags = RICHACE_SPECIAL_WHO; + ace->e_mask = other_mask; + ace->e_id.special = RICHACE_EVERYONE_SPECIAL_ID; + ace++; + } + return acl; } EXPORT_SYMBOL_GPL(richacl_from_mode_unmasked); -- 2.1.0