diff options
Diffstat (limited to 'lib/libcapsicum')
| -rw-r--r-- | lib/libcapsicum/Makefile | 19 | ||||
| -rw-r--r-- | lib/libcapsicum/Makefile.depend | 10 | ||||
| -rw-r--r-- | lib/libcapsicum/capsicum_helpers.3 | 181 | ||||
| -rw-r--r-- | lib/libcapsicum/capsicum_helpers.h | 205 |
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_ */ |