From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andreas Gruenbacher Subject: [RFC v4 27/31] richacl: Create richacl from mode values Date: Wed, 24 Jun 2015 23:57:16 +0200 Message-ID: <1435183040-22726-28-git-send-email-agruenba@redhat.com> References: <1435183040-22726-1-git-send-email-agruenba@redhat.com> To: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-fsdevel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-nfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, samba-technical-w/Ol4Ecudpl8XjKLYN78aQ@public.gmane.org, linux-security-module-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Return-path: In-Reply-To: <1435183040-22726-1-git-send-email-agruenba-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> Sender: linux-api-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-fsdevel.vger.kernel.org Signed-off-by: Andreas Gruenbacher --- fs/richacl_compat.c | 88 +++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/richacl.h | 1 + 2 files changed, 89 insertions(+) diff --git a/fs/richacl_compat.c b/fs/richacl_compat.c index c9c33df..03c04ab 100644 --- a/fs/richacl_compat.c +++ b/fs/richacl_compat.c @@ -818,3 +818,91 @@ richacl_apply_masks(struct richacl **acl, kuid_t owner) return 0; } EXPORT_SYMBOL_GPL(richacl_apply_masks); + +/** + * richacl_from_mode - create an acl which corresponds to @mode + * + * The resulting acl doesn't have the RICHACL_MASKED flag set. + * + * @mode: file mode including the file type + */ +struct richacl * +richacl_from_mode(mode_t mode) +{ + unsigned int owner_mask = richacl_mode_to_mask(mode >> 6); + 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; + + /* 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; + } + + denied = ~owner_mask & (group_mask | other_mask); + if (denied) + entries++; /* owner@ deny entry needed */ + if (owner_mask & ~(group_mask & other_mask)) + entries++; /* owner@ allow entry needed */ + denied = ~group_mask & other_mask; + if (denied) + entries++; /* group@ deny entry needed */ + if (group_mask & ~other_mask) + entries++; /* group@ allow entry needed */ + if (other_mask) + entries++; /* everyone@ allow entry needed */ + + acl = richacl_alloc(entries, GFP_KERNEL); + if (!acl) + return NULL; + acl->a_owner_mask = owner_mask; + acl->a_group_mask = group_mask; + acl->a_other_mask = other_mask; + ace = acl->a_entries; + + 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 (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 = ~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 (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++; + } + 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); diff --git a/include/linux/richacl.h b/include/linux/richacl.h index 3d1af44..d59ad20 100644 --- a/include/linux/richacl.h +++ b/include/linux/richacl.h @@ -337,5 +337,6 @@ extern struct richacl *richacl_create(struct inode *, struct inode *); /* richacl_compat.c */ extern int richacl_apply_masks(struct richacl **, kuid_t); +extern struct richacl *richacl_from_mode(mode_t); #endif /* __RICHACL_H */ -- 2.4.2