Extended Attribute support, from FreeBSD/TrustedBSD. ok art@ deraadt@

libc support pieces

2 files changed, 235 insertions, 1 deletions

diff --git a/lib/libc/sys/Makefile.inc b/lib/libc/sys/Makefile.inc
index 1505d12c36c..365a30a28b1 100644
--- a/lib/libc/sys/Makefile.inc
+++ b/lib/libc/sys/Makefile.inc
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile.inc,v 1.50 2002/02/21 21:19:20 art Exp $
+#	$OpenBSD: Makefile.inc,v 1.51 2002/02/22 21:06:01 drahn Exp $
 #	$NetBSD: Makefile.inc,v 1.35 1995/10/16 23:49:07 jtc Exp $
 #	@(#)Makefile.inc	8.1 (Berkeley) 6/17/93
 
@@ -61,6 +61,10 @@ ASM=	accept.o access.o acct.o adjtime.o bind.o chdir.o chflags.o chmod.o \
 	utimes.o vadvise.o wait4.o write.o writev.o xfspioctl.o __semctl.o \
 	__syscall.o __sysctl.o
 
+ASM+=	extattrctl.o extattr_set_file.o extattr_get_file.o \
+	extattr_delete_file.o extattr_set_fd.o extattr_get_fd.o \
+	extattr_delete_fd.o
+
 GASM=	${ASM:.o=.go}
 PASM=	${ASM:.o=.po}
 SASM=	${ASM:.o=.so}
@@ -226,6 +230,14 @@ MAN+=	accept.2 access.2 acct.2 adjtime.2 bind.2 brk.2 chdir.2 chflags.2 \
 	sysarch.2 syscall.2 truncate.2 umask.2 unlink.2 utimes.2 vfork.2 \
 	wait.2 write.2
 
+MAN+=	extattr_get_file.2
+MLINKS+=extattr_get_file.2 extattr_set_file.2 \
+	extattr_get_file.2 extattr_delete_file.2 \
+	extattr_get_file.2 extattr_get_fd.2 \
+	extattr_get_file.2 extattr_set_fd.2 \
+	extattr_get_file.2 extattr_delete_fd.2 \
+	extattr_get_file.2 extattr.2
+
 MAN+=	msgctl.2 shmctl.2 shmat.2 semop.2 semget.2 semctl.2 msgsnd.2 msgrcv.2 \
 	msgget.2 shmget.2
 
diff --git a/lib/libc/sys/extattr_get_file.2 b/lib/libc/sys/extattr_get_file.2
new file mode 100644
index 00000000000..c20699875a7
--- /dev/null
+++ b/lib/libc/sys/extattr_get_file.2
@@ -0,0 +1,222 @@
+.\" $OpenBSD: extattr_get_file.2,v 1.1 2002/02/22 21:06:01 drahn Exp $
+.\"
+.\" Copyright (c) 2001 Dima Dorfman <dima@unixfreak.org>
+.\" All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\" $FreeBSD: extattr_get_file.2,v 1.7 2002/02/10 04:46:28 rwatson Exp $
+.\"
+.Dd March 28, 2001
+.Dt EXTATTR 2
+.Os
+.Sh NAME
+.Nm extattr_get_fd ,
+.Nm extattr_set_fd ,
+.Nm extattr_delete_fd ,
+.Nm extattr_get_file ,
+.Nm extattr_set_file ,
+.Nm extattr_delete_file
+.Nd system calls to manipulate VFS extended attributes
+.Sh LIBRARY
+.Lb libc
+.Sh SYNOPSIS
+.In sys/types.h
+.In sys/extattr.h
+.In sys/uio.h
+.Ft ssize_t
+.Fn extattr_get_fd "int fd" "int attrnamespace" "const char *attrname" "void *data" "size_t nbytes"
+.Ft int
+.Fn extattr_set_fd "int fd" "int attrnamespace" "const char *attrname" "const void *data" "size_t nbytes"
+.Ft int
+.Fn extattr_delete_fd "int fd" "int attrnamespace" "const char *attrname"
+.Ft ssize_t
+.Fn extattr_get_file "const char *path" "int attrnamespace" "const char *attrname" "void *data" "size_t nbytes"
+.Ft int
+.Fn extattr_set_file "const char *path" "int attrnamespace" "const char *attrname" "const void *data" "size_t nbytes"
+.Ft int
+.Fn extattr_delete_file "const char *path" "int attrnamespace" "const char *attrname"
+.Sh DESCRIPTION
+Named extended attributes are meta-data associated with vnodes
+representing files and directories.
+They exist as
+.Qq Li name=value
+pairs within a set of namespaces.
+The
+.Fn extattr_get_file
+call retrieves the value of the specified extended attribute into
+a buffer pointed to by
+.Fa data
+of size
+.Fa nbytes
+.
+The
+.Fn extattr_set_file
+call sets the value of the specified extended attribute to the data
+described by
+.Fa data .
+The
+.Fn extattr_delete_file
+call deletes the extended attribute specified.
+The
+.Fn extattr_get_file
+and
+.Fn extattr_set_file
+calls consume the
+.Fa data
+and
+.Fa nbytes
+arguments in the style of
+.Xr read 2
+and
+.Xr write 2 ,
+respectively.
+If
+.Fa data
+is
+.Dv NULL
+in a call to
+.Fn extattr_get_file
+then the size of defined extended attribute data will be returned, rather
+than the quantity read, permitting applications to test the size of the
+data without performing a read.
+.Pp
+The
+.Fn extatttr_get_fd ,
+.Fn extattr_set_fd ,
+and
+.Fn extattr_delete_fd
+calls are identical to their
+.Qq Li _file
+counterparts except for the first argument.
+The
+.Qq Li _fd
+functions take a file descriptor, while the
+.Qq Li _file
+functions take a path.
+Both arguments describe a file associated with the extended attribute
+that should be manipulated.
+.Pp
+The following arguments are common to all the system calls described here:
+.Bl -tag -width attrnamespace
+.It Fa attrnamespace
+the namespace in which the extended attribute resides; see
+.Xr extattr 9
+.It Fa attrname
+the name of the extended attribute
+.El
+.Pp
+Named extended attribute semantics vary by filesystem implementing the call.
+Not all operations may be supported for a particular attribute.
+Additionally, the format of the data in
+.Fa data
+is attribute-specific.
+.Pp
+For more information on named extended attributes, please see
+.Xr extattr 9 .
+.Sh CAVEAT
+This interface is under active development, and as such is subject to
+change as applications are adapted to use it.
+Developers are discouraged from relying on its stability.
+.Sh RETURN VALUES
+If successful, the
+.Fn extattr_get_file
+and
+.Fn extattr_set_file
+calls return the number of bytes
+that were read or written from the
+.Fa data ,
+respectively, or if
+.Fa data
+was
+.Dv NULL ,
+then
+.Fn extattr_get_file
+returns the number of bytes available to read.
+If any of the calls are unsuccessful, the value \-1 is returned
+and the global variable
+.Va errno
+is set to indicate the error.
+.Pp
+.Rv -std extattr_delete_file
+.Sh ERRORS
+The following errors may be returned by the system calls themselves.
+Additionally, the filesystem implementing the call may return any
+other errors it desires.
+.Bl -tag -width Er
+.It Bq Er EFAULT
+.Fa attrnamespace ,
+.Fa attrname ,
+or the memory range defined by
+.Fa data
+and
+.Fa nbytes
+points outside the process's allocated address space.
+.It Bq Er ENAMETOOLONG
+The attribute name was longer than
+.Dv EXTATTR_MAXNAMELEN .
+.El
+.Pp
+The
+.Fn extattr_get_fd ,
+.Fn extattr_set_fd ,
+and
+.Fn extattr_delete_fd
+functions may also fail if:
+.Bl -tag -width Er
+.It Bq Er EBADF
+The file descriptor referenced by
+.Fa fd
+was invalid.
+.El
+.Pp
+Additionally, the
+.Fn extattr_get_file ,
+.Fn extattr_set_file ,
+and
+.Fn extattr_delete_file
+calls may also fail due to the following errors:
+.Bl -tag -width Er
+.It Bq Er ENOTDIR
+A component of the path prefix is not a directory.
+.It Bq Er ENAMETOOLONG
+A component of a pathname exceeded 255 characters,
+or an entire path name exceeded 1023 characters.
+.It Bq Er ENOENT
+A component of the path name that must exist does not exist.
+.It Bq Er EACCES
+Search permission is denied for a component of the path prefix.
+.\" XXX are any missing?
+.El
+.Sh SEE ALSO
+.Xr extattr 3 ,
+.Xr extattrctl 8 ,
+.Xr getextattr 8 ,
+.Xr setextattr 8 ,
+.Xr extattr 9 ,
+.Sh HISTORY
+Extended attribute support was developed as part of the
+.Tn TrustedBSD
+Project, and introduced in
+.Ox 3.1 .
+It was developed to support security extensions requiring additional labels
+to be associated with each file or directory.