Merge r257633:

- Add manual pages for capability rights (rights(4)), cap_rights_init(3)
  family of functions and cap_rights_get(3) function.
- Update remaining Capsicum-related manual pages.

Sponsored by:	The FreeBSD Foundation
Reviewed by:	bdrewery
Approved by:	re (glebius)

2 files changed, 250 insertions, 10 deletions

diff --git a/lib/libc/capability/Makefile.inc b/lib/libc/capability/Makefile.inc
index 934fc8b..85be56a 100644
--- a/lib/libc/capability/Makefile.inc
+++ b/lib/libc/capability/Makefile.inc
@@ -1,19 +1,18 @@
 # $FreeBSD$
 
 # capability sources
-.PATH: ${.CURDIR}/../../sys/kern
+.PATH: ${.CURDIR}/../../sys/kern ${.CURDIR}/capability
 
 SRCS+=	subr_capability.c
 
 SYM_MAPS+=	${.CURDIR}/capability/Symbol.map
 
-#MAN+=	cap_rights_init.3
-
-#MLINKS+=cap_rights_init.3 cap_rights_set.3
-#MLINKS+=cap_rights_init.3 cap_rights_clear.3
-#MLINKS+=cap_rights_init.3 cap_rights_is_set.3
-#MLINKS+=cap_rights_init.3 cap_rights_is_valid.3
-#MLINKS+=cap_rights_init.3 cap_rights_merge.3
-#MLINKS+=cap_rights_init.3 cap_rights_remove.3
-#MLINKS+=cap_rights_init.3 cap_rights_contains.3
+MAN+=	cap_rights_init.3
 
+MLINKS+=cap_rights_init.3 cap_rights_set.3
+MLINKS+=cap_rights_init.3 cap_rights_clear.3
+MLINKS+=cap_rights_init.3 cap_rights_is_set.3
+MLINKS+=cap_rights_init.3 cap_rights_is_valid.3
+MLINKS+=cap_rights_init.3 cap_rights_merge.3
+MLINKS+=cap_rights_init.3 cap_rights_remove.3
+MLINKS+=cap_rights_init.3 cap_rights_contains.3
diff --git a/lib/libc/capability/cap_rights_init.3 b/lib/libc/capability/cap_rights_init.3
new file mode 100644
index 0000000..458e9d3
--- /dev/null
+++ b/lib/libc/capability/cap_rights_init.3
@@ -0,0 +1,241 @@
+.\"
+.\" Copyright (c) 2013 The FreeBSD Foundation
+.\" All rights reserved.
+.\"
+.\" This documentation was written by Pawel Jakub Dawidek under sponsorship
+.\" from the FreeBSD Foundation.
+.\"
+.\" 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.
+.\"
+.\" $FreeBSD$
+.\"
+.Dd September 23, 2013
+.Dt CAP_RIGHTS_INIT 3
+.Os
+.Sh NAME
+.Nm cap_rights_init ,
+.Nm cap_rights_set ,
+.Nm cap_rights_clear ,
+.Nm cap_rights_is_set ,
+.Nm cap_rights_is_valid ,
+.Nm cap_rights_merge ,
+.Nm cap_rights_remove ,
+.Nm cap_rights_contains
+.Nd manage cap_rights_t structure
+.Sh LIBRARY
+.Lb libc
+.Sh SYNOPSIS
+.In sys/capability.h
+.Ft cap_rights_t *
+.Fn cap_rights_init "cap_rights_t *rights" "..."
+.Ft cap_rights_t *
+.Fn cap_rights_set "cap_rights_t *rights" "..."
+.Ft cap_rights_t *
+.Fn cap_rights_clear "cap_rights_t *rights" "..."
+.Ft bool
+.Fn cap_rights_is_set "const cap_rights_t *rights" "..."
+.Ft bool
+.Fn cap_rights_is_valid "const cap_rights_t *rights"
+.Ft cap_rights_t *
+.Fn cap_rights_merge "cap_rights_t *dst" "const cap_rights_t *src"
+.Ft cap_rights_t *
+.Fn cap_rights_remove "cap_rights_t *dst" "const cap_rights_t *src"
+.Ft bool
+.Fn cap_rights_contains "const cap_rights_t *big" "const cap_rights_t *little"
+.Sh DESCRIPTION
+The functions documented here allow to manage the
+.Vt cap_rights_t
+structure.
+.Pp
+Capability rights should be separated with comma when passed to the
+.Fn cap_rights_init ,
+.Fn cap_rights_set ,
+.Fn cap_rights_clear
+and
+.Fn cap_rights_is_set
+functions.
+For example:
+.Bd -literal
+cap_rights_set(&rights, CAP_READ, CAP_WRITE, CAP_FSTAT, CAP_SEEK);
+.Ed
+.Pp
+The complete list of the capability rights can be found in the
+.Xr rights 4
+manual page.
+.Pp
+The
+.Fn cap_rights_init
+function initialize provided
+.Vt cap_rights_t
+structure.
+Only properly initialized structure can be passed to the remaining functions.
+For convenience the structure can be filled with capability rights instead of
+calling the
+.Fn cap_rights_set
+function later.
+For even more convenience pointer to the given structure is returned, so it can
+be directly passed to
+.Xr cap_rights_limit 2 :
+.Bd -literal
+cap_rights_t rights;
+
+if (cap_rights_limit(fd, cap_rights_init(&rights, CAP_READ, CAP_WRITE)) < 0)
+	err(1, "Unable to limit capability rights");
+.Ed
+.Pp
+The
+.Fn cap_rights_set
+function adds the given capability rights to the given
+.Vt cap_rights_t
+structure.
+.Pp
+The
+.Fn cap_rights_clear
+function removes the given capability rights from the given
+.Vt cap_rights_t
+structure.
+.Pp
+The
+.Fn cap_rights_is_set
+function checks if all the given capability rights are set for the given
+.Vt cap_rights_t
+structure.
+.Pp
+The
+.Fn cap_rights_is_valid
+function verifies if the given
+.Vt cap_rights_t
+structure is valid.
+.Pp
+The
+.Fn cap_rights_merge
+function merges all capability rights present in the
+.Fa src
+structure into the
+.Fa dst
+structure.
+.Pp
+The
+.Fn cap_rights_remove
+function removes all capability rights present in the
+.Fa src
+structure from the
+.Fa dst
+structure.
+.Pp
+The
+.Fn cap_rights_contains
+function checks if the
+.Fa big
+structure contains all capability rights present in the
+.Fa little
+structure.
+.Sh RETURN VALUES
+The functions never fail.
+In case an invalid capability right or an invalid
+.Vt cap_rights_t
+structure is given as an argument, the program will be aborted.
+.Pp
+The
+.Fn cap_rights_init ,
+.Fn cap_rights_set
+and
+.Fn cap_rights_clear
+functions return pointer to the
+.Vt cap_rights_t
+structure given in the
+.Fa rights
+argument.
+.Pp
+The
+.Fn cap_rights_merge
+and
+.Fn cap_rights_remove
+functions return pointer to the
+.Vt cap_rights_t
+structure given in the
+.Fa dst
+argument.
+.Pp
+The
+.Fn cap_rights_is_set
+returns
+.Va true
+if all the given capability rights are set in the
+.Fa rights
+argument.
+.Pp
+The
+.Fn cap_rights_is_valid
+function performs various checks to see if the given
+.Vt cap_rights_t
+structure is valid and returns
+.Va true
+if it is.
+.Pp
+The
+.Fn cap_rights_contains
+function returns
+.Va true
+if all capability rights set in the
+.Fa little
+structure are also present in the
+.Fa big
+structure.
+.Sh EXAMPLES
+The following example demonstrates how to prepare a
+.Vt cap_rights_t
+structure to be passed to the
+.Xr cap_rights_limit 2
+system call.
+.Bd -literal
+cap_rights_t rights;
+int fd;
+
+fd = open("/tmp/foo", O_RDWR);
+if (fd < 0)
+	err(1, "open() failed");
+
+cap_rights_init(&rights, CAP_FSTAT, CAP_READ);
+
+if (allow_write_and_seek)
+	cap_rights_set(&rights, CAP_WRITE, CAP_SEEK);
+
+if (dont_allow_seek)
+	cap_rights_clear(&rights, CAP_SEEK);
+
+if (cap_rights_limit(fd, &rights) < 0 && errno != ENOSYS)
+	err(1, "cap_rights_limit() failed");
+.Ed
+.Sh SEE ALSO
+.Xr cap_rights_limit 2 ,
+.Xr open 2 ,
+.Xr capsicum 4 ,
+.Xr rights 4
+.Sh HISTORY
+Support for capabilities and capabilities mode was developed as part of the
+.Tn TrustedBSD
+Project.
+.Sh AUTHORS
+This family of functions was created by
+.An Pawel Jakub Dawidek Aq pawel@dawidek.net
+under sponsorship from the FreeBSD Foundation.