From: Andreas Gruenbacher <agruenba-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> To: Alexander Viro <viro-RmSDqhL/yNMiFSDQTTA3OLVCufUGDwFn@public.gmane.org> Cc: Andreas Gruenbacher <agruenba-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>, Christoph Hellwig <hch-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>, "Theodore Ts'o" <tytso-3s7WtUTddSA@public.gmane.org>, Andreas Dilger <adilger.kernel-m1MBpc4rdrD3fQ9qLvQP4Q@public.gmane.org>, "J. Bruce Fields" <bfields-uC3wQj2KruNg9hUCZPvPmw@public.gmane.org>, Jeff Layton <jlayton-vpEMnDpepFuMZCB2o+C8xQ@public.gmane.org>, Trond Myklebust <trond.myklebust-7I+n7zu2hftEKMMhf/gKZA@public.gmane.org>, Anna Schumaker <anna.schumaker-HgOvQuBEEgTQT0dZR+AlfA@public.gmane.org>, Dave Chinner <david-FqsqvQoI3Ljby3iVrkZq2A@public.gmane.org>, linux-ext4-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, xfs-VZNHf3L845pBDgjK7y7TUQ@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-fsdevel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-nfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-cifs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Subject: [PATCH v27 13/21] richacl: Check if an acl is equivalent to a file mode Date: Tue, 11 Oct 2016 14:50:48 +0200 [thread overview] Message-ID: <1476190256-1677-14-git-send-email-agruenba@redhat.com> (raw) In-Reply-To: <1476190256-1677-1-git-send-email-agruenba-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> ACLs are considered equivalent to file modes if they only consist of owner@, group@, and everyone@ entries, the owner@ permissions do not depend on whether the owner is a member in the owning group, and no inheritance flags are set. This test is used to avoid storing richacls if the acl can be computed from the file permission bits. Signed-off-by: Andreas Gruenbacher <agruenba-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> Reviewed-by: J. Bruce Fields <bfields-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> Reviewed-by: Jeff Layton <jlayton-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> --- fs/richacl.c | 104 ++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/richacl.h | 1 + 2 files changed, 105 insertions(+) diff --git a/fs/richacl.c b/fs/richacl.c index a199245..1022983 100644 --- a/fs/richacl.c +++ b/fs/richacl.c @@ -612,3 +612,107 @@ richacl_chmod(struct inode *inode, umode_t mode) return retval; } EXPORT_SYMBOL(richacl_chmod); + +/** + * richacl_equiv_mode - compute the mode equivalent of @acl + * + * An acl is considered equivalent to a file mode if it only consists of + * owner@, group@, and everyone@ entries and the owner@ permissions do not + * depend on whether the owner is a member in the owning group. + */ +int +richacl_equiv_mode(const struct richacl *acl, umode_t *mode_p) +{ + umode_t mode = *mode_p; + + /* + * The RICHACE_DELETE_CHILD flag is meaningless for non-directories, so + * we ignore it. + */ + unsigned int x = S_ISDIR(mode) ? 0 : RICHACE_DELETE_CHILD; + struct { + unsigned int allowed; + unsigned int defined; /* allowed or denied */ + } owner = { + .defined = RICHACE_POSIX_ALWAYS_ALLOWED | + RICHACE_POSIX_OWNER_ALLOWED | x, + }, group = { + .defined = RICHACE_POSIX_ALWAYS_ALLOWED | x, + }, everyone = { + .defined = RICHACE_POSIX_ALWAYS_ALLOWED | x, + }; + const struct richace *ace; + + if (acl->a_flags & ~(RICHACL_WRITE_THROUGH | RICHACL_MASKED)) + return -1; + + richacl_for_each_entry(ace, acl) { + if (ace->e_flags & ~RICHACE_SPECIAL_WHO) + return -1; + + if (richace_is_owner(ace) || richace_is_everyone(ace)) { + x = ace->e_mask & ~owner.defined; + if (richace_is_allow(ace)) { + unsigned int group_denied = + group.defined & ~group.allowed; + + if (x & group_denied) + return -1; + owner.allowed |= x; + } else /* if (richace_is_deny(ace)) */ { + if (x & group.allowed) + return -1; + } + owner.defined |= x; + + if (richace_is_everyone(ace)) { + x = ace->e_mask; + if (richace_is_allow(ace)) { + group.allowed |= + x & ~group.defined; + everyone.allowed |= + x & ~everyone.defined; + } + group.defined |= x; + everyone.defined |= x; + } + } else if (richace_is_group(ace)) { + x = ace->e_mask & ~group.defined; + if (richace_is_allow(ace)) + group.allowed |= x; + group.defined |= x; + } else + return -1; + } + + if (group.allowed & ~owner.defined) + return -1; + + if (acl->a_flags & RICHACL_MASKED) { + if (acl->a_flags & RICHACL_WRITE_THROUGH) { + owner.allowed = acl->a_owner_mask; + everyone.allowed = acl->a_other_mask; + } else { + owner.allowed &= acl->a_owner_mask; + everyone.allowed &= acl->a_other_mask; + } + group.allowed &= acl->a_group_mask; + } + + mode = (mode & ~S_IRWXUGO) | + (richacl_mask_to_mode(owner.allowed) << 6) | + (richacl_mask_to_mode(group.allowed) << 3) | + richacl_mask_to_mode(everyone.allowed); + + /* Mask flags we can ignore */ + x = S_ISDIR(mode) ? 0 : RICHACE_DELETE_CHILD; + + if (((richacl_mode_to_mask(mode >> 6) ^ owner.allowed) & ~x) || + ((richacl_mode_to_mask(mode >> 3) ^ group.allowed) & ~x) || + ((richacl_mode_to_mask(mode) ^ everyone.allowed) & ~x)) + return -1; + + *mode_p = mode; + return 0; +} +EXPORT_SYMBOL_GPL(richacl_equiv_mode); diff --git a/include/linux/richacl.h b/include/linux/richacl.h index 3cd5e53..a865f37 100644 --- a/include/linux/richacl.h +++ b/include/linux/richacl.h @@ -190,5 +190,6 @@ extern unsigned int richacl_mode_to_mask(umode_t); extern int richacl_permission(struct inode *, const struct richacl *, int); extern void richacl_compute_max_masks(struct richacl *); extern int richacl_chmod(struct inode *, umode_t); +extern int richacl_equiv_mode(const struct richacl *, umode_t *); #endif /* __RICHACL_H */ -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html
WARNING: multiple messages have this Message-ID (diff)
From: Andreas Gruenbacher <agruenba@redhat.com> To: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Andreas Gruenbacher <agruenba@redhat.com>, Christoph Hellwig <hch@infradead.org>, "Theodore Ts'o" <tytso@mit.edu>, Andreas Dilger <adilger.kernel@dilger.ca>, "J. Bruce Fields" <bfields@fieldses.org>, Jeff Layton <jlayton@poochiereds.net>, Trond Myklebust <trond.myklebust@primarydata.com>, Anna Schumaker <anna.schumaker@netapp.com>, Dave Chinner <david@fromorbit.com>, linux-ext4@vger.kernel.org, xfs@oss.sgi.com, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-nfs@vger.kernel.org, linux-cifs@vger.kernel.org, linux-api@vger.kernel.org Subject: [PATCH v27 13/21] richacl: Check if an acl is equivalent to a file mode Date: Tue, 11 Oct 2016 14:50:48 +0200 [thread overview] Message-ID: <1476190256-1677-14-git-send-email-agruenba@redhat.com> (raw) In-Reply-To: <1476190256-1677-1-git-send-email-agruenba@redhat.com> ACLs are considered equivalent to file modes if they only consist of owner@, group@, and everyone@ entries, the owner@ permissions do not depend on whether the owner is a member in the owning group, and no inheritance flags are set. This test is used to avoid storing richacls if the acl can be computed from the file permission bits. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Reviewed-by: J. Bruce Fields <bfields@redhat.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> --- fs/richacl.c | 104 ++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/richacl.h | 1 + 2 files changed, 105 insertions(+) diff --git a/fs/richacl.c b/fs/richacl.c index a199245..1022983 100644 --- a/fs/richacl.c +++ b/fs/richacl.c @@ -612,3 +612,107 @@ richacl_chmod(struct inode *inode, umode_t mode) return retval; } EXPORT_SYMBOL(richacl_chmod); + +/** + * richacl_equiv_mode - compute the mode equivalent of @acl + * + * An acl is considered equivalent to a file mode if it only consists of + * owner@, group@, and everyone@ entries and the owner@ permissions do not + * depend on whether the owner is a member in the owning group. + */ +int +richacl_equiv_mode(const struct richacl *acl, umode_t *mode_p) +{ + umode_t mode = *mode_p; + + /* + * The RICHACE_DELETE_CHILD flag is meaningless for non-directories, so + * we ignore it. + */ + unsigned int x = S_ISDIR(mode) ? 0 : RICHACE_DELETE_CHILD; + struct { + unsigned int allowed; + unsigned int defined; /* allowed or denied */ + } owner = { + .defined = RICHACE_POSIX_ALWAYS_ALLOWED | + RICHACE_POSIX_OWNER_ALLOWED | x, + }, group = { + .defined = RICHACE_POSIX_ALWAYS_ALLOWED | x, + }, everyone = { + .defined = RICHACE_POSIX_ALWAYS_ALLOWED | x, + }; + const struct richace *ace; + + if (acl->a_flags & ~(RICHACL_WRITE_THROUGH | RICHACL_MASKED)) + return -1; + + richacl_for_each_entry(ace, acl) { + if (ace->e_flags & ~RICHACE_SPECIAL_WHO) + return -1; + + if (richace_is_owner(ace) || richace_is_everyone(ace)) { + x = ace->e_mask & ~owner.defined; + if (richace_is_allow(ace)) { + unsigned int group_denied = + group.defined & ~group.allowed; + + if (x & group_denied) + return -1; + owner.allowed |= x; + } else /* if (richace_is_deny(ace)) */ { + if (x & group.allowed) + return -1; + } + owner.defined |= x; + + if (richace_is_everyone(ace)) { + x = ace->e_mask; + if (richace_is_allow(ace)) { + group.allowed |= + x & ~group.defined; + everyone.allowed |= + x & ~everyone.defined; + } + group.defined |= x; + everyone.defined |= x; + } + } else if (richace_is_group(ace)) { + x = ace->e_mask & ~group.defined; + if (richace_is_allow(ace)) + group.allowed |= x; + group.defined |= x; + } else + return -1; + } + + if (group.allowed & ~owner.defined) + return -1; + + if (acl->a_flags & RICHACL_MASKED) { + if (acl->a_flags & RICHACL_WRITE_THROUGH) { + owner.allowed = acl->a_owner_mask; + everyone.allowed = acl->a_other_mask; + } else { + owner.allowed &= acl->a_owner_mask; + everyone.allowed &= acl->a_other_mask; + } + group.allowed &= acl->a_group_mask; + } + + mode = (mode & ~S_IRWXUGO) | + (richacl_mask_to_mode(owner.allowed) << 6) | + (richacl_mask_to_mode(group.allowed) << 3) | + richacl_mask_to_mode(everyone.allowed); + + /* Mask flags we can ignore */ + x = S_ISDIR(mode) ? 0 : RICHACE_DELETE_CHILD; + + if (((richacl_mode_to_mask(mode >> 6) ^ owner.allowed) & ~x) || + ((richacl_mode_to_mask(mode >> 3) ^ group.allowed) & ~x) || + ((richacl_mode_to_mask(mode) ^ everyone.allowed) & ~x)) + return -1; + + *mode_p = mode; + return 0; +} +EXPORT_SYMBOL_GPL(richacl_equiv_mode); diff --git a/include/linux/richacl.h b/include/linux/richacl.h index 3cd5e53..a865f37 100644 --- a/include/linux/richacl.h +++ b/include/linux/richacl.h @@ -190,5 +190,6 @@ extern unsigned int richacl_mode_to_mask(umode_t); extern int richacl_permission(struct inode *, const struct richacl *, int); extern void richacl_compute_max_masks(struct richacl *); extern int richacl_chmod(struct inode *, umode_t); +extern int richacl_equiv_mode(const struct richacl *, umode_t *); #endif /* __RICHACL_H */ -- 2.7.4
next prev parent reply other threads:[~2016-10-11 12:50 UTC|newest] Thread overview: 44+ messages / expand[flat|nested] mbox.gz Atom feed top 2016-10-11 12:50 [PATCH v27 00/21] Richacls (Core and Ext4) Andreas Gruenbacher 2016-10-11 12:50 ` [PATCH v27 01/21] vfs: Add IS_ACL() and IS_RICHACL() tests Andreas Gruenbacher [not found] ` <1476190256-1677-1-git-send-email-agruenba-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> 2016-10-11 12:50 ` [PATCH v27 02/21] vfs: Add MAY_CREATE_FILE and MAY_CREATE_DIR permission flags Andreas Gruenbacher 2016-10-11 12:50 ` Andreas Gruenbacher 2016-12-02 9:22 ` Miklos Szeredi 2017-02-13 15:34 ` Andreas Gruenbacher 2016-10-11 12:50 ` [PATCH v27 03/21] vfs: Add MAY_DELETE_SELF and MAY_DELETE_CHILD " Andreas Gruenbacher 2016-10-11 12:50 ` Andreas Gruenbacher 2016-12-02 9:57 ` Miklos Szeredi 2016-12-06 20:15 ` J. Bruce Fields [not found] ` <20161206201529.GA1203-uC3wQj2KruNg9hUCZPvPmw@public.gmane.org> 2016-12-06 21:13 ` Jeremy Allison 2016-12-06 21:13 ` Jeremy Allison 2016-12-06 21:25 ` Miklos Szeredi [not found] ` <CAJfpegsvoZfzUXyCJrxXAG6dxk8HMCGMEKA0E-6FzWNGkM17Tw-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org> 2016-12-06 21:36 ` Jeremy Allison 2016-12-06 21:36 ` Jeremy Allison 2017-02-13 15:40 ` Andreas Gruenbacher 2017-02-13 15:40 ` Andreas Gruenbacher [not found] ` <CAELBmZCgttywPy3EtkFao7SPESaw8VB5K6x7PTRk7gwSk7sXqg-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org> 2017-02-13 15:42 ` Andreas Gruenbacher 2017-02-13 15:42 ` Andreas Gruenbacher 2016-10-11 12:50 ` [PATCH v27 04/21] vfs: Add permission flags for setting file attributes Andreas Gruenbacher 2016-10-11 12:50 ` Andreas Gruenbacher 2016-10-11 12:50 ` [PATCH v27 05/21] richacl: In-memory representation and helper functions Andreas Gruenbacher 2016-10-11 12:50 ` Andreas Gruenbacher 2016-10-11 12:50 ` [PATCH v27 06/21] richacl: Permission mapping functions Andreas Gruenbacher 2016-10-11 12:50 ` Andreas Gruenbacher 2016-10-11 12:50 ` Andreas Gruenbacher [this message] 2016-10-11 12:50 ` [PATCH v27 13/21] richacl: Check if an acl is equivalent to a file mode Andreas Gruenbacher 2016-10-11 12:50 ` [PATCH v27 14/21] richacl: Create-time inheritance Andreas Gruenbacher 2016-10-11 12:50 ` Andreas Gruenbacher 2016-10-11 12:50 ` [PATCH v27 16/21] richacl: xattr mapping functions Andreas Gruenbacher 2016-10-11 12:50 ` Andreas Gruenbacher 2016-10-11 12:50 ` [PATCH v27 21/21] ext4: Add richacl feature flag Andreas Gruenbacher 2016-10-11 12:50 ` Andreas Gruenbacher 2016-10-11 12:50 ` [PATCH v27 07/21] richacl: Permission check algorithm Andreas Gruenbacher 2016-10-11 12:50 ` [PATCH v27 08/21] richacl: Compute maximum file masks from an acl Andreas Gruenbacher 2016-10-11 12:50 ` [PATCH v27 09/21] vfs: Cache base_acl objects in inodes Andreas Gruenbacher 2016-10-11 12:50 ` [PATCH v27 10/21] vfs: Add get_richacl and set_richacl inode operations Andreas Gruenbacher 2016-10-11 12:50 ` [PATCH v27 11/21] vfs: Cache richacl in struct inode Andreas Gruenbacher 2016-10-11 12:50 ` [PATCH v27 12/21] richacl: Update the file masks in chmod() Andreas Gruenbacher 2016-10-11 12:50 ` [PATCH v27 15/21] richacl: Automatic Inheritance Andreas Gruenbacher 2016-10-11 12:50 ` [PATCH v27 17/21] richacl: Add richacl xattr handler Andreas Gruenbacher 2016-10-11 12:50 ` [PATCH v27 18/21] vfs: Add richacl permission checking Andreas Gruenbacher 2016-10-11 12:50 ` [PATCH v27 19/21] vfs: Move check_posix_acl and check_richacl out of fs/namei.c Andreas Gruenbacher 2016-10-11 12:50 ` [PATCH v27 20/21] ext4: Add richacl support Andreas Gruenbacher
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=1476190256-1677-14-git-send-email-agruenba@redhat.com \ --to=agruenba-h+wxahxf7alqt0dzr+alfa@public.gmane.org \ --cc=adilger.kernel-m1MBpc4rdrD3fQ9qLvQP4Q@public.gmane.org \ --cc=anna.schumaker-HgOvQuBEEgTQT0dZR+AlfA@public.gmane.org \ --cc=bfields-uC3wQj2KruNg9hUCZPvPmw@public.gmane.org \ --cc=david-FqsqvQoI3Ljby3iVrkZq2A@public.gmane.org \ --cc=hch-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org \ --cc=jlayton-vpEMnDpepFuMZCB2o+C8xQ@public.gmane.org \ --cc=linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \ --cc=linux-cifs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \ --cc=linux-ext4-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \ --cc=linux-fsdevel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \ --cc=linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \ --cc=linux-nfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \ --cc=trond.myklebust-7I+n7zu2hftEKMMhf/gKZA@public.gmane.org \ --cc=tytso-3s7WtUTddSA@public.gmane.org \ --cc=viro-RmSDqhL/yNMiFSDQTTA3OLVCufUGDwFn@public.gmane.org \ --cc=xfs-VZNHf3L845pBDgjK7y7TUQ@public.gmane.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.