From 5a453d5f5b8cff5a58b7c65df3822a2a6094f7b4 Mon Sep 17 00:00:00 2001
From: Mariusz Zaborski <oshogbo@FreeBSD.org>
Date: Sun, 4 Nov 2018 17:22:58 +0000
Subject: [PATCH] libcapsicum: Introduce caph_{rights,ioctls,fcntls}_limit

The idea behind those functions is not to force consumers to remember that there
is a need to check errno on failure. We already have a caph_enter(3) function
which does the same for cap_enter(2).

MFC after:	2 weeks
---
 lib/libcapsicum/Makefile           |  1 +
 lib/libcapsicum/capsicum_helpers.3 | 30 ++++++++++++++++++++++++------
 lib/libcapsicum/capsicum_helpers.h | 29 +++++++++++++++++++++++++++++
 3 files changed, 54 insertions(+), 6 deletions(-)

diff --git a/lib/libcapsicum/Makefile b/lib/libcapsicum/Makefile
index 85a0a56c2ba2..1adf57666f7e 100644
--- a/lib/libcapsicum/Makefile
+++ b/lib/libcapsicum/Makefile
@@ -8,6 +8,7 @@ MAN+=	capsicum_helpers.3
 
 MLINKS+=capsicum_helpers.3 caph_enter.3
 MLINKS+=capsicum_helpers.3 caph_enter_casper.3
+MLINKS+=capsicum_helpers.3 caph_rights_limit.3
 MLINKS+=capsicum_helpers.3 caph_limit_stream.3
 MLINKS+=capsicum_helpers.3 caph_limit_stdin.3
 MLINKS+=capsicum_helpers.3 caph_limit_stderr.3
diff --git a/lib/libcapsicum/capsicum_helpers.3 b/lib/libcapsicum/capsicum_helpers.3
index c22a201d8f43..8d4b875bf94c 100644
--- a/lib/libcapsicum/capsicum_helpers.3
+++ b/lib/libcapsicum/capsicum_helpers.3
@@ -24,7 +24,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd July 18, 2018
+.Dd November 4, 2018
 .Dt CAPSICUM_HELPERS 3
 .Os
 .Sh NAME
@@ -34,7 +34,12 @@
 .Nm caph_limit_stdout ,
 .Nm caph_limit_stdio ,
 .Nm caph_cache_tzdata ,
-.Nm caph_cache_catpages
+.Nm caph_cache_catpages ,
+.Nm caph_enter ,
+.Nm caph_enter_casper ,
+.Nm caph_rights_limit ,
+.Nm caph_ioctls_limit ,
+.Nm caph_fcntls_limit
 .Nd "set of the capsicum helpers, part of the libcapsicum"
 .Sh LIBRARY
 .Lb libcapsicum
@@ -45,7 +50,11 @@
 .Ft int
 .Fn caph_enter_casper "void"
 .Ft int
-.Fn caph_limit_stream "int fd" "int flags"
+.Fn caph_rights_limit "inf fd" "const cap_righst_t *rights"
+.Ft int
+.Fn caph_ioctls_limit "inf fd" "const unsigned long *cmds" "size_t ncmds"
+.Ft int
+.Fn caph_fcntls_limit "inf fd" "uint32_t fcntlrights"
 .Ft int
 .Fn caph_limit_stdin "void"
 .Ft int
@@ -60,9 +69,17 @@
 .Fn caph_cache_catpages "void"
 .Sh DESCRIPTION
 The
-.Nm caph_enter
-is equivalent to the
-.Xr cap_enter 2
+.Nm caph_enter ,
+.Nm caph_rights_limit ,
+.Nm caph_ioctls_limit
+and
+.Nm caph_fcntls_limit
+are respectively equivalent to
+.Xr cap_enter 2 ,
+.Xr cap_rights_limit 2 ,
+.Xr cap_ioctls_limit 2
+and
+.Xr cap_fcntls_limit 2 ,
 it returns success when the kernel is built without support of the capability
 mode.
 .Pp
@@ -125,4 +142,5 @@ among others.
 .Ed
 .Sh SEE ALSO
 .Xr cap_enter 2 ,
+.Xr cap_rights_limit 2 ,
 .Xr rights 4
diff --git a/lib/libcapsicum/capsicum_helpers.h b/lib/libcapsicum/capsicum_helpers.h
index 60c894f35a6e..c94cd867f2e1 100644
--- a/lib/libcapsicum/capsicum_helpers.h
+++ b/lib/libcapsicum/capsicum_helpers.h
@@ -136,6 +136,35 @@ caph_enter(void)
 	return (0);
 }
 
+static __inline int
+caph_rights_limit(int fd, const cap_rights_t *rights)
+{
+
+	if (cap_rights_limit(fd, rights) < 0 && errno != ENOSYS)
+		return (-1);
+
+	return (0);
+}
+
+static __inline int
+caph_ioctls_limit(int fd, const unsigned long *cmds, size_t ncmds)
+{
+
+	if (cap_ioctls_limit(fd, cmds, ncmds) < 0 && errno != ENOSYS)
+		return (-1);
+
+	return (0);
+}
+
+static __inline int
+caph_fcntls_limit(int fd, uint32_t fcntlrights)
+{
+
+	if (caph_fcntls_limit(fd, fcntlrights) < 0 && errno != ENOSYS)
+		return (-1);
+
+	return (0);
+}
 
 static __inline int
 caph_enter_casper(void)