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-rw-r--r--lib/libcapsicum/Makefile19
-rw-r--r--lib/libcapsicum/Makefile.depend10
-rw-r--r--lib/libcapsicum/capsicum_helpers.3181
-rw-r--r--lib/libcapsicum/capsicum_helpers.h205
4 files changed, 415 insertions, 0 deletions
diff --git a/lib/libcapsicum/Makefile b/lib/libcapsicum/Makefile
new file mode 100644
index 000000000000..3cb476e67e28
--- /dev/null
+++ b/lib/libcapsicum/Makefile
@@ -0,0 +1,19 @@
+INCS= capsicum_helpers.h
+
+MAN+= capsicum_helpers.3
+
+MLINKS+=capsicum_helpers.3 caph_enter.3
+MLINKS+=capsicum_helpers.3 caph_enter_casper.3
+MLINKS+=capsicum_helpers.3 caph_stream_rights.3
+MLINKS+=capsicum_helpers.3 caph_rights_limit.3
+MLINKS+=capsicum_helpers.3 caph_fcntls_limit.3
+MLINKS+=capsicum_helpers.3 caph_ioctls_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
+MLINKS+=capsicum_helpers.3 caph_limit_stdout.3
+MLINKS+=capsicum_helpers.3 caph_limit_stdio.3
+MLINKS+=capsicum_helpers.3 caph_cache_tzdata.3
+MLINKS+=capsicum_helpers.3 caph_cache_catpages.3
+
+.include <bsd.lib.mk>
diff --git a/lib/libcapsicum/Makefile.depend b/lib/libcapsicum/Makefile.depend
new file mode 100644
index 000000000000..11aba52f82cf
--- /dev/null
+++ b/lib/libcapsicum/Makefile.depend
@@ -0,0 +1,10 @@
+# Autogenerated - do NOT edit!
+
+DIRDEPS = \
+
+
+.include <dirdeps.mk>
+
+.if ${DEP_RELDIR} == ${_DEP_RELDIR}
+# local dependencies - needed for -jN in clean tree
+.endif
diff --git a/lib/libcapsicum/capsicum_helpers.3 b/lib/libcapsicum/capsicum_helpers.3
new file mode 100644
index 000000000000..fdb4f6f87977
--- /dev/null
+++ b/lib/libcapsicum/capsicum_helpers.3
@@ -0,0 +1,181 @@
+.\" Copyright (c) 2016 Mariusz Zaborski <oshogbo@FreeBSD.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 AUTHORS 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 AUTHORS 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.
+.\"
+.Dd May 16, 2024
+.Dt CAPSICUM_HELPERS 3
+.Os
+.Sh NAME
+.Nm caph_limit_stream ,
+.Nm caph_limit_stdin ,
+.Nm caph_limit_stderr ,
+.Nm caph_limit_stdout ,
+.Nm caph_limit_stdio ,
+.Nm caph_stream_rights ,
+.Nm caph_cache_tzdata ,
+.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
+.Sh SYNOPSIS
+.In capsicum_helpers.h
+.Ft int
+.Fn caph_enter "void"
+.Ft int
+.Fn caph_enter_casper "void"
+.Ft int
+.Fn caph_rights_limit "int fd" "const cap_rights_t *rights"
+.Ft int
+.Fn caph_ioctls_limit "int fd" "const unsigned long *cmds" "size_t ncmds"
+.Ft int
+.Fn caph_fcntls_limit "int fd" "uint32_t fcntlrights"
+.Ft int
+.Fn caph_limit_stream "int fd" "int flags"
+.Ft int
+.Fn caph_limit_stdin "void"
+.Ft int
+.Fn caph_limit_stderr "void"
+.Ft int
+.Fn caph_limit_stdout "void"
+.Ft int
+.Fn caph_limit_stdio "void"
+.Ft void
+.Fn caph_stream_rights "cap_rights_t *" "int flags"
+.Ft void
+.Fn caph_cache_tzdata "void"
+.Ft void
+.Fn caph_cache_catpages "void"
+.Sh DESCRIPTION
+The
+.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
+The
+.Nm caph_enter_casper
+is equivalent to the
+.Nm caph_enter
+it returns success when the system is built without Casper support.
+.Pp
+The
+.Nm capsicum helpers
+are a set of a inline functions which simplify modifying programs to use
+Capsicum.
+The goal is to reduce duplicated code patterns.
+The
+.Nm capsicum helpers
+are part of
+.Nm libcapsicum
+but there is no need to link to the library.
+.Pp
+.Fn caph_limit_stream
+restricts capabilities on
+.Fa fd
+to only those needed by POSIX stream objects (that is, FILEs).
+.Pp
+These flags can be provided:
+.Pp
+.Bl -tag -width "CAPH_IGNORE_EBADF" -compact -offset indent
+.It Dv CAPH_IGNORE_EBADF
+Do not return an error if file descriptor is invalid.
+.It Dv CAPH_READ
+Set CAP_READ on limited descriptor.
+.It Dv CAPH_WRITE
+Set CAP_WRITE on limited descriptor.
+.El
+.Pp
+.Fn caph_limit_stdin ,
+.Fn caph_limit_stderr
+and
+.Fn caph_limit_stdout
+limit standard descriptors using the
+.Nm caph_limit_stream
+function.
+.Pp
+.Fn caph_limit_stdio
+limits stdin, stderr and stdout.
+.Pp
+.Nm caph_stream_rights
+may be used to initialize
+.Fa rights
+with the same rights that a stream would be limited to, as if
+.Fn caph_limit_stream
+had been invoked using the same
+.Fa flags .
+.Pp
+.Fn caph_cache_tzdata
+precaches all timezone data needed to use
+.Li libc
+local time functions.
+.Pp
+.Fn caph_cache_catpages
+caches Native Language Support (NLS) data.
+NLS data is used for localized error printing by
+.Xr strerror 3
+and
+.Xr err 3 ,
+among others.
+.Sh RETURN VALUES
+Upon successful completion,
+.Fn caph_enter ,
+.Fn caph_enter_casper ,
+.Fn caph_rights_limit ,
+.Fn caph_ioctls_limit ,
+.Fn caph_fcntls_limit ,
+.Fn caph_limit_stream ,
+.Fn caph_limit_stdin ,
+.Fn caph_limit_stderr ,
+.Fn caph_limit_stdout ,
+and
+.Fn caph_limit_stdio
+return a value
+of 0.
+Otherwise, a value of -1 is returned and the global variable
+.Va errno
+is set to indicate the error.
+.Pp
+Functions
+.Fn caph_stream_rights ,
+.Fn caph_cache_tzdata ,
+and
+.Fn caph_cache_catpages
+can not fail.
+.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
new file mode 100644
index 000000000000..a6c696aa9a8e
--- /dev/null
+++ b/lib/libcapsicum/capsicum_helpers.h
@@ -0,0 +1,205 @@
+/*-
+ * Copyright (c) 2016 Mariusz Zaborski <oshogbo@FreeBSD.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.
+ */
+
+#ifndef _CAPSICUM_HELPERS_H_
+#define _CAPSICUM_HELPERS_H_
+
+#include <sys/param.h>
+#include <sys/capsicum.h>
+#include <sys/ioctl.h>
+
+#include <errno.h>
+#include <nl_types.h>
+#include <termios.h>
+#include <time.h>
+#include <unistd.h>
+
+#include <libcasper.h>
+
+#define CAPH_IGNORE_EBADF 0x0001
+#define CAPH_READ 0x0002
+#define CAPH_WRITE 0x0004
+#define CAPH_LOOKUP 0x0008
+
+__BEGIN_DECLS
+
+static const unsigned long caph_stream_cmds[] =
+ {
+#ifdef TIOCGETA
+ TIOCGETA,
+#endif
+#ifdef TIOCGWINSZ
+ TIOCGWINSZ,
+#endif
+#ifdef FIODTYPE
+ FIODTYPE,
+#endif
+ };
+static const uint32_t caph_stream_fcntls = CAP_FCNTL_GETFL;
+
+static __inline void
+caph_stream_rights(cap_rights_t *rights, int flags)
+{
+
+ cap_rights_init(rights, CAP_EVENT, CAP_FCNTL, CAP_FSTAT,
+ CAP_IOCTL, CAP_SEEK);
+
+ if ((flags & CAPH_READ) != 0)
+ cap_rights_set(rights, CAP_READ);
+ if ((flags & CAPH_WRITE) != 0)
+ cap_rights_set(rights, CAP_WRITE);
+ if ((flags & CAPH_LOOKUP) != 0)
+ cap_rights_set(rights, CAP_LOOKUP);
+}
+
+static __inline int
+caph_limit_stream(int fd, int flags)
+{
+ cap_rights_t rights;
+
+ caph_stream_rights(&rights, flags);
+ if (cap_rights_limit(fd, &rights) < 0 && errno != ENOSYS) {
+ if (errno == EBADF && (flags & CAPH_IGNORE_EBADF) != 0)
+ return (0);
+ return (-1);
+ }
+
+ if (cap_ioctls_limit(fd, caph_stream_cmds,
+ nitems(caph_stream_cmds)) < 0 && errno != ENOSYS)
+ return (-1);
+
+ if (cap_fcntls_limit(fd, caph_stream_fcntls) < 0 && errno != ENOSYS)
+ return (-1);
+
+ return (0);
+}
+
+static __inline int
+caph_limit_stdin(void)
+{
+
+ return (caph_limit_stream(STDIN_FILENO, CAPH_READ));
+}
+
+static __inline int
+caph_limit_stderr(void)
+{
+
+ return (caph_limit_stream(STDERR_FILENO, CAPH_WRITE));
+}
+
+static __inline int
+caph_limit_stdout(void)
+{
+
+ return (caph_limit_stream(STDOUT_FILENO, CAPH_WRITE));
+}
+
+static __inline int
+caph_limit_stdio(void)
+{
+ const int iebadf = CAPH_IGNORE_EBADF;
+
+ if (caph_limit_stream(STDIN_FILENO, CAPH_READ | iebadf) == -1 ||
+ caph_limit_stream(STDOUT_FILENO, CAPH_WRITE | iebadf) == -1 ||
+ caph_limit_stream(STDERR_FILENO, CAPH_WRITE | iebadf) == -1)
+ return (-1);
+ return (0);
+}
+
+static __inline void
+caph_cache_tzdata(void)
+{
+ time_t delta;
+
+ tzset();
+
+ /*
+ * The tzset() function does not cache all time zones.
+ * Some functions, such as gmtime(), require a GMT time zone.
+ * The only way to cache them is to call the function directly.
+ */
+ delta = 0;
+ (void)gmtime(&delta);
+}
+
+static __inline void
+caph_cache_catpages(void)
+{
+
+ (void)catopen("libc", NL_CAT_LOCALE);
+}
+
+static __inline int
+caph_enter(void)
+{
+
+ if (cap_enter() < 0 && errno != ENOSYS)
+ return (-1);
+
+ 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 (cap_fcntls_limit(fd, fcntlrights) < 0 && errno != ENOSYS)
+ return (-1);
+
+ return (0);
+}
+
+static __inline int
+caph_enter_casper(void)
+{
+
+ return (CASPER_SUPPORT == 0 ? 0 : caph_enter());
+}
+
+__END_DECLS
+
+#endif /* _CAPSICUM_HELPERS_H_ */