diff options
| -rw-r--r-- | ChangeLog | 38 | ||||
| -rw-r--r-- | config.h.in | 3 | ||||
| -rw-r--r-- | config.make.in | 1 | ||||
| -rwxr-xr-x | configure | 167 | ||||
| -rw-r--r-- | nscd/Makefile | 8 | ||||
| -rw-r--r-- | nscd/connections.c | 10 | ||||
| -rw-r--r-- | nscd/nscd.c | 12 | ||||
| -rw-r--r-- | nscd/nscd_proto.h | 4 | ||||
| -rw-r--r-- | nscd/nscd_stat.c | 15 | ||||
| -rw-r--r-- | nscd/selinux.c | 266 | ||||
| -rw-r--r-- | nscd/selinux.h | 55 |
11 files changed, 577 insertions, 2 deletions
@@ -1,3 +1,41 @@ +2004-09-16 Ulrich Drepper <drepper@redhat.com> + + * configure.in: Add test for required SELinux features. + * config.make.in: Add have-selinux entry. + * config.h.in: Add HAVE_SELINUX entry. + * nscd/Makefile (nscd-modules): Add selinux. + (CFLAGS-selinux.c): Add -fpie. + Define selinux-LIBS and use in link line. + * nscd/connections.c (handle_request): Check access SELinux permissions + before processing request. + * nscd/nscd.c (main): Initialize selinux_enabled and stop avc thread. + * nscd/nscd_stat.c: Transmit and print AVC statistics. + * nscd/selinux.c: New file. + * nscd/selinux.h: New file. + +2004-09-16 Jakub Jelinek <jakub@redhat.com> + + * nscd/nscd_helper.c (__nscd_unmap, get_mapping): Use __munmap + instead of munmap. + + * nscd/Makefile (CFLAGS-aicache.c): Set to -fpie. + +2004-09-16 Thorsten Kukuk <kukuk@suse.de> + + * sysdeps/posix/getaddrinfo.c (gaih_inet): Check + __nss_not_use_nscd_hosts variable if nscd should be used or not. + +2004-09-16 Ulrich Drepper <drepper@redhat.com> + + * nscd/nscd_proto.h: Define NSS_NSCD_RETRY. + Add __nscd_getai prototype. + * nss/getXXbyYY_r.c: Remode definition of NSS_NSCD_RETRY. + * nscd/nscd-client.h: Remove __nscd_getai prototype. + * nscd/nscd_getai.c: Include nscd_proto.h. + + * elf/ldd.bash.in: Add support for SELinux environments. + Patch by Stephen Smalley <sds@epoch.ncsc.mil>. + 2004-09-16 Roland McGrath <roland@redhat.com> * configure.in (--with-headers): Let argument contain a : separated diff --git a/config.h.in b/config.h.in index bd990c6627..db3defc6b0 100644 --- a/config.h.in +++ b/config.h.in @@ -18,6 +18,9 @@ --with-elf. */ #undef HAVE_ELF +/* Define if building with SELinux support. Set by --with-selinux. */ +#undef HAVE_SELINUX + /* Define if using XCOFF. Set by --with-xcoff. */ #undef HAVE_XCOFF diff --git a/config.make.in b/config.make.in index b48dbb4fc5..81cb95b77f 100644 --- a/config.make.in +++ b/config.make.in @@ -58,6 +58,7 @@ have-cpp-asm-debuginfo = @libc_cv_cpp_asm_debuginfo@ enable-check-abi = @enable_check_abi@ have-forced-unwind = @libc_cv_forced_unwind@ have-fpie = @libc_cv_fpie@ +have-selinux = @have_selinux@ have-cc-with-libunwind = @libc_cv_cc_with_libunwind@ fno-unit-at-a-time = @fno_unit_at_a_time@ bind-now = @bindnow@ @@ -313,7 +313,7 @@ ac_includes_default="\ # include <unistd.h> #endif" -ac_subst_vars='SHELL PATH_SEPARATOR PACKAGE_NAME PACKAGE_TARNAME PACKAGE_VERSION PACKAGE_STRING PACKAGE_BUGREPORT exec_prefix prefix program_transform_name bindir sbindir libexecdir datadir sysconfdir sharedstatedir localstatedir libdir includedir oldincludedir infodir mandir build_alias host_alias target_alias DEFS ECHO_C ECHO_N ECHO_T LIBS with_fp with_cvs enable_check_abi oldest_abi bindnow force_install all_warnings build build_cpu build_vendor build_os host host_cpu host_vendor host_os subdirs add_ons base_machine sysnames INSTALL_PROGRAM INSTALL_SCRIPT INSTALL_DATA LN_S CC CFLAGS LDFLAGS CPPFLAGS ac_ct_CC OBJEXT BUILD_CC cross_compiling CPP CXX CXXFLAGS ac_ct_CXX AR OBJDUMP RANLIB ac_ct_RANLIB MIG AS LD PWD_P MAKE MSGFMT MAKEINFO SED AUTOCONF SYSINCLUDES libc_cv_gcc_static_libgcc BASH libc_cv_have_bash2 KSH libc_cv_have_ksh AWK PERL INSTALL_INFO BISON VERSIONING libc_cv_asm_protected_directive libc_cv_initfinit_array libc_cv_cc_with_libunwind libc_cv_z_nodelete libc_cv_z_nodlopen libc_cv_z_initfirst libc_cv_z_relro libc_cv_Bgroup libc_cv_libgcc_s_suffix libc_cv_as_needed ASFLAGS_config libc_cv_z_combreloc libc_cv_z_execstack libc_cv_fpie fno_unit_at_a_time libc_cv_have_initfini libc_cv_cpp_asm_debuginfo no_whole_archive exceptions LIBGD EGREP sizeof_long_double libc_cv_gcc_unwind_find_fde uname_sysname uname_release uname_version old_glibc_headers libc_cv_slibdir libc_cv_localedir libc_cv_sysconfdir libc_cv_rootsbindir libc_cv_forced_unwind use_ldconfig ldd_rewrite_script gnu_ld gnu_as elf xcoff static shared pic_default profile omitfp bounded static_nss nopic_initfini DEFINES linux_doors mach_interface_list VERSION RELEASE LIBOBJS LTLIBOBJS' +ac_subst_vars='SHELL PATH_SEPARATOR PACKAGE_NAME PACKAGE_TARNAME PACKAGE_VERSION PACKAGE_STRING PACKAGE_BUGREPORT exec_prefix prefix program_transform_name bindir sbindir libexecdir datadir sysconfdir sharedstatedir localstatedir libdir includedir oldincludedir infodir mandir build_alias host_alias target_alias DEFS ECHO_C ECHO_N ECHO_T LIBS with_fp with_cvs enable_check_abi oldest_abi bindnow force_install all_warnings build build_cpu build_vendor build_os host host_cpu host_vendor host_os subdirs add_ons base_machine sysnames INSTALL_PROGRAM INSTALL_SCRIPT INSTALL_DATA LN_S CC CFLAGS LDFLAGS CPPFLAGS ac_ct_CC OBJEXT BUILD_CC cross_compiling CPP CXX CXXFLAGS ac_ct_CXX AR OBJDUMP RANLIB ac_ct_RANLIB MIG AS LD PWD_P MAKE MSGFMT MAKEINFO SED AUTOCONF SYSINCLUDES libc_cv_gcc_static_libgcc BASH libc_cv_have_bash2 KSH libc_cv_have_ksh AWK PERL INSTALL_INFO BISON VERSIONING libc_cv_asm_protected_directive libc_cv_initfinit_array libc_cv_cc_with_libunwind libc_cv_z_nodelete libc_cv_z_nodlopen libc_cv_z_initfirst libc_cv_z_relro libc_cv_Bgroup libc_cv_libgcc_s_suffix libc_cv_as_needed ASFLAGS_config libc_cv_z_combreloc libc_cv_z_execstack libc_cv_fpie fno_unit_at_a_time libc_cv_have_initfini libc_cv_cpp_asm_debuginfo no_whole_archive exceptions LIBGD have_selinux EGREP sizeof_long_double libc_cv_gcc_unwind_find_fde uname_sysname uname_release uname_version old_glibc_headers libc_cv_slibdir libc_cv_localedir libc_cv_sysconfdir libc_cv_rootsbindir libc_cv_forced_unwind use_ldconfig ldd_rewrite_script gnu_ld gnu_as elf xcoff static shared pic_default profile omitfp bounded static_nss nopic_initfini DEFINES linux_doors mach_interface_list VERSION RELEASE LIBOBJS LTLIBOBJS' ac_subst_files='' # Initialize some variables set by options. @@ -895,6 +895,7 @@ Optional Packages: --with-fp if using floating-point hardware [default=yes] --with-binutils=PATH specify location of binutils (as and ld) --with-elf if using the ELF object format + --with-selinux if building with SELinux support --with-xcoff if using the XCOFF object format --without-cvs if CVS should not be used --with-headers=PATH location of system headers to use (for example @@ -1485,6 +1486,14 @@ else elf=no fi; +# Check whether --with-selinux or --without-selinux was given. +if test "${with_selinux+set}" = set; then + withval="$with_selinux" + with_selinux=$withval +else + with_selinux=auto +fi; + # Check whether --with-xcoff or --without-xcoff was given. if test "${with_xcoff+set}" = set; then withval="$with_xcoff" @@ -6694,6 +6703,161 @@ echo "$as_me:$LINENO: result: $LIBGD" >&5 echo "${ECHO_T}$LIBGD" >&6 +# SELinux detection +if test x$with_selinux = xno ; then + have_selinux=no; +else + # See if we have the SELinux library + echo "$as_me:$LINENO: checking for is_selinux_enabled in -lselinux" >&5 +echo $ECHO_N "checking for is_selinux_enabled in -lselinux... $ECHO_C" >&6 +if test "${ac_cv_lib_selinux_is_selinux_enabled+set}" = set; then + echo $ECHO_N "(cached) $ECHO_C" >&6 +else + ac_check_lib_save_LIBS=$LIBS +LIBS="-lselinux $LIBS" +cat >conftest.$ac_ext <<_ACEOF +/* confdefs.h. */ +_ACEOF +cat confdefs.h >>conftest.$ac_ext +cat >>conftest.$ac_ext <<_ACEOF +/* end confdefs.h. */ + +/* Override any gcc2 internal prototype to avoid an error. */ +#ifdef __cplusplus +extern "C" +#endif +/* We use char because int might match the return type of a gcc2 + builtin and then its argument prototype would still apply. */ +char is_selinux_enabled (); +int +main () +{ +is_selinux_enabled (); + ; + return 0; +} +_ACEOF +rm -f conftest.$ac_objext conftest$ac_exeext +if { (eval echo "$as_me:$LINENO: \"$ac_link\"") >&5 + (eval $ac_link) 2>conftest.er1 + ac_status=$? + grep -v '^ *+' conftest.er1 >conftest.err + rm -f conftest.er1 + cat conftest.err >&5 + echo "$as_me:$LINENO: \$? = $ac_status" >&5 + (exit $ac_status); } && + { ac_try='test -z "$ac_c_werror_flag" + || test ! -s conftest.err' + { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5 + (eval $ac_try) 2>&5 + ac_status=$? + echo "$as_me:$LINENO: \$? = $ac_status" >&5 + (exit $ac_status); }; } && + { ac_try='test -s conftest$ac_exeext' + { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5 + (eval $ac_try) 2>&5 + ac_status=$? + echo "$as_me:$LINENO: \$? = $ac_status" >&5 + (exit $ac_status); }; }; then + ac_cv_lib_selinux_is_selinux_enabled=yes +else + echo "$as_me: failed program was:" >&5 +sed 's/^/| /' conftest.$ac_ext >&5 + +ac_cv_lib_selinux_is_selinux_enabled=no +fi +rm -f conftest.err conftest.$ac_objext \ + conftest$ac_exeext conftest.$ac_ext +LIBS=$ac_check_lib_save_LIBS +fi +echo "$as_me:$LINENO: result: $ac_cv_lib_selinux_is_selinux_enabled" >&5 +echo "${ECHO_T}$ac_cv_lib_selinux_is_selinux_enabled" >&6 +if test $ac_cv_lib_selinux_is_selinux_enabled = yes; then + have_selinux=yes +else + have_selinux=no +fi + + # See if we have the SELinux header with the NSCD permissions in it. + if test x$have_selinux = xyes ; then + echo "$as_me:$LINENO: checking for NSCD Flask permissions in selinux/av_permissions.h" >&5 +echo $ECHO_N "checking for NSCD Flask permissions in selinux/av_permissions.h... $ECHO_C" >&6 + cat >conftest.$ac_ext <<_ACEOF +/* confdefs.h. */ +_ACEOF +cat confdefs.h >>conftest.$ac_ext +cat >>conftest.$ac_ext <<_ACEOF +/* end confdefs.h. */ +#include <selinux/av_permissions.h> +int +main () +{ +#ifdef NSCD__SHMEMHOST + return 0; + #else + #error NSCD__SHMEMHOST not defined + #endif + ; + return 0; +} +_ACEOF +rm -f conftest.$ac_objext +if { (eval echo "$as_me:$LINENO: \"$ac_compile\"") >&5 + (eval $ac_compile) 2>conftest.er1 + ac_status=$? + grep -v '^ *+' conftest.er1 >conftest.err + rm -f conftest.er1 + cat conftest.err >&5 + echo "$as_me:$LINENO: \$? = $ac_status" >&5 + (exit $ac_status); } && + { ac_try='test -z "$ac_c_werror_flag" + || test ! -s conftest.err' + { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5 + (eval $ac_try) 2>&5 + ac_status=$? + echo "$as_me:$LINENO: \$? = $ac_status" >&5 + (exit $ac_status); }; } && + { ac_try='test -s conftest.$ac_objext' + { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5 + (eval $ac_try) 2>&5 + ac_status=$? + echo "$as_me:$LINENO: \$? = $ac_status" >&5 + (exit $ac_status); }; }; then + have_selinux=yes +else + echo "$as_me: failed program was:" >&5 +sed 's/^/| /' conftest.$ac_ext >&5 + +have_selinux=no +fi +rm -f conftest.err conftest.$ac_objext conftest.$ac_ext + echo "$as_me:$LINENO: result: $have_selinux" >&5 +echo "${ECHO_T}$have_selinux" >&6 + fi + + if test x$with_selinux = xauto ; then + if test x$have_selinux = xno ; then + { echo "$as_me:$LINENO: WARNING: Sufficiently new SELinux library not found" >&5 +echo "$as_me: WARNING: Sufficiently new SELinux library not found" >&2;} + fi + else + if test x$have_selinux = xno ; then + { { echo "$as_me:$LINENO: error: SELinux explicitly required, and SELinux library not found" >&5 +echo "$as_me: error: SELinux explicitly required, and SELinux library not found" >&2;} + { (exit 1); exit 1; }; } + fi + fi +fi +# Check if we're building with SELinux support. +if test "x$have_selinux" = xyes; then + +cat >>confdefs.h <<\_ACEOF +#define HAVE_SELINUX 1 +_ACEOF + +fi + + echo "$as_me:$LINENO: checking for egrep" >&5 echo $ECHO_N "checking for egrep... $ECHO_C" >&6 @@ -8310,6 +8474,7 @@ s,@libc_cv_cpp_asm_debuginfo@,$libc_cv_cpp_asm_debuginfo,;t t s,@no_whole_archive@,$no_whole_archive,;t t s,@exceptions@,$exceptions,;t t s,@LIBGD@,$LIBGD,;t t +s,@have_selinux@,$have_selinux,;t t s,@EGREP@,$EGREP,;t t s,@sizeof_long_double@,$sizeof_long_double,;t t s,@libc_cv_gcc_unwind_find_fde@,$libc_cv_gcc_unwind_find_fde,;t t diff --git a/nscd/Makefile b/nscd/Makefile index 3e6a8b5182..d24bf9c2a6 100644 --- a/nscd/Makefile +++ b/nscd/Makefile @@ -51,6 +51,11 @@ otherlibs += $(nssobjdir)/libnss_files.a $(resolvobjdir)/libnss_dns.a \ $(resolvobjdir)/libresolv.a endif +ifeq (yes,$(have-selinux)) +nscd-modules += selinux +selinux-LIBS := -lselinux +endif + distribute := nscd.h nscd-client.h dbg_log.h \ $(addsuffix .c, $(filter-out xmalloc, $(nscd-modules))) \ nscd_nischeck.c TODO nscd.conf nscd.init nscd_proto.h \ @@ -83,6 +88,7 @@ CFLAGS-xstrdup.c = -fpie CFLAGS-mem.c = -fpie CFLAGS-nscd_setup_thread.c = -fpie CFLAGS-aicache.c = -fpie +CFLAGS-selinux.c = -fpie $(objpfx)nscd: $(addprefix $(objpfx),$(nscd-modules:=.o)) $(LINK.o) -pie -Wl,-O1 \ @@ -91,7 +97,7 @@ $(objpfx)nscd: $(addprefix $(objpfx),$(nscd-modules:=.o)) $(extra-B-$(@F:lib%.so=%).so) $(load-map-file) \ $(LDFLAGS) $(LDFLAGS-$(@F)) \ -L$(subst :, -L,$(rpath-link)) -Wl,-rpath-link=$(rpath-link) \ - -o $@ $^ $(common-objpfx)libc_nonshared.a + -o $@ $^ $(selinux-LIBS) $(common-objpfx)libc_nonshared.a endif # This makes sure -DNOT_IN_libc is passed for all these modules. diff --git a/nscd/connections.c b/nscd/connections.c index fe33c76bcf..164fdfbc84 100644 --- a/nscd/connections.c +++ b/nscd/connections.c @@ -41,6 +41,7 @@ #include "nscd.h" #include "dbg_log.h" +#include "selinux.h" /* Number of bytes of data we initially reserve for each hash table bucket. */ @@ -592,6 +593,15 @@ cannot handle old request version %d; current version is %d"), return; } + /* Make the SELinux check before we go on to the standard checks. We + need to verify that the request type is valid, since it has not + yet been checked at this point. */ + if (selinux_enabled + && __builtin_expect (req->type, GETPWBYNAME) >= GETPWBYNAME + && __builtin_expect (req->type, LASTREQ) < LASTREQ + && nscd_request_avc_has_perm (fd, req->type) != 0) + return; + struct database_dyn *db = serv2db[req->type]; if ((__builtin_expect (req->type, GETPWBYNAME) >= GETPWBYNAME diff --git a/nscd/nscd.c b/nscd/nscd.c index facea5ecdb..b0e7a20947 100644 --- a/nscd/nscd.c +++ b/nscd/nscd.c @@ -44,6 +44,7 @@ #include "dbg_log.h" #include "nscd.h" +#include "selinux.h" #include "../nss/nsswitch.h" #include <device-nrs.h> @@ -126,6 +127,9 @@ main (int argc, char **argv) /* Set the text message domain. */ textdomain (PACKAGE); + /* Determine if the kernel has SELinux support. */ + nscd_selinux_enabled (&selinux_enabled); + /* Parse and process arguments. */ argp_parse (&argp, argc, argv, 0, &remaining, NULL); @@ -244,6 +248,10 @@ main (int argc, char **argv) signal (SIGTSTP, SIG_IGN); } + /* Start the SELinux AVC. */ + if (selinux_enabled) + nscd_avc_init (); + signal (SIGINT, termination_handler); signal (SIGQUIT, termination_handler); signal (SIGTERM, termination_handler); @@ -421,6 +429,10 @@ termination_handler (int signum) // XXX async OK? msync (dbs[cnt].head, dbs[cnt].memsize, MS_ASYNC); + /* Shutdown the SELinux AVC. */ + if (selinux_enabled) + nscd_avc_destroy (); + _exit (EXIT_SUCCESS); } diff --git a/nscd/nscd_proto.h b/nscd/nscd_proto.h index b0ee03cd84..eb685a5eb0 100644 --- a/nscd/nscd_proto.h +++ b/nscd/nscd_proto.h @@ -27,6 +27,10 @@ /* Interval in which we transfer retry to contact the NSCD. */ #define NSS_NSCD_RETRY 100 +/* Type needed in the interfaces. */ +struct nscd_ai_result; + + /* Variables for communication between NSCD handler functions and NSS. */ extern int __nss_not_use_nscd_passwd attribute_hidden; extern int __nss_not_use_nscd_group attribute_hidden; diff --git a/nscd/nscd_stat.c b/nscd/nscd_stat.c index ebdfeac1d4..3e3be5bc8c 100644 --- a/nscd/nscd_stat.c +++ b/nscd/nscd_stat.c @@ -29,6 +29,12 @@ #include "nscd.h" #include "dbg_log.h" +#include "selinux.h" +#ifdef HAVE_SELINUX +# include <selinux/selinux.h> +# include <selinux/avc.h> +#endif /* HAVE_SELINUX */ + /* We use this to make sure the receiver is the same. */ static const char compilation[21] = __DATE__ " " __TIME__; @@ -71,6 +77,9 @@ struct statdata unsigned long int client_queued; int ndbs; struct dbstat dbs[lastdb]; +#ifdef HAVE_SELINUX + struct avc_cache_stats cstats; +#endif /* HAVE_SELINUX */ }; @@ -113,6 +122,9 @@ send_stats (int fd, struct database_dyn dbs[lastdb]) } } + if (selinux_enabled) + nscd_avc_cache_stats (&data.cstats); + if (TEMP_FAILURE_RETRY (write (fd, &data, sizeof (data))) != sizeof (data)) { char buf[256]; @@ -276,6 +288,9 @@ receive_print_stats (void) data.dbs[i].addfailed, check_file, dbnames[i]); } + if (selinux_enabled) + nscd_avc_print_stats (&data.cstats); + close (fd); exit (0); diff --git a/nscd/selinux.c b/nscd/selinux.c new file mode 100644 index 0000000000..0f975f71f6 --- /dev/null +++ b/nscd/selinux.c @@ -0,0 +1,266 @@ +/* SELinux access controls for nscd. + Copyright (C) 2004 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Matthew Rickard <mjricka@epoch.ncsc.mil>, 2004. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <error.h> +#include <errno.h> +#include <libintl.h> +#include <pthread.h> +#include <stdarg.h> +#include <stdio.h> +#include <stdlib.h> +#include <syslog.h> +#include <selinux/av_permissions.h> +#include <selinux/avc.h> +#include <selinux/flask.h> +#include <selinux/selinux.h> + +#include "dbg_log.h" +#include "selinux.h" + + +#ifdef HAVE_SELINUX +/* Global variable to tell if the kernel has SELinux support. */ +int selinux_enabled; + +/* Define mappings of access vector permissions to request types. */ +static const int perms[LASTREQ] = +{ + [GETPWBYNAME] = NSCD__GETPWD, + [GETPWBYUID] = NSCD__GETPWD, + [GETGRBYNAME] = NSCD__GETGRP, + [GETGRBYGID] = NSCD__GETGRP, + [GETHOSTBYNAME] = NSCD__GETHOST, + [GETHOSTBYNAMEv6] = NSCD__GETHOST, + [GETHOSTBYADDR] = NSCD__GETHOST, + [GETHOSTBYADDRv6] = NSCD__GETHOST, + [GETSTAT] = NSCD__GETSTAT, + [SHUTDOWN] = NSCD__ADMIN, + [INVALIDATE] = NSCD__ADMIN, + [GETFDPW] = NSCD__SHMEMPWD, + [GETFDGR] = NSCD__SHMEMGRP, + [GETFDHST] = NSCD__SHMEMHOST, + [GETAI] = NSCD__GETHOST +}; + +/* Store an entry ref to speed AVC decisions. */ +static struct avc_entry_ref aeref; + +/* Thread to listen for SELinux status changes via netlink. */ +static pthread_t avc_notify_thread; + +/* Prototypes for AVC callback functions. */ +static void *avc_create_thread (void (*run) (void)); +static void avc_stop_thread (void *thread); +static void *avc_alloc_lock (void); +static void avc_get_lock (void *lock); +static void avc_release_lock (void *lock); +static void avc_free_lock (void *lock); + +/* AVC callback structures for use in avc_init. */ +static const struct avc_log_callback log_cb = +{ + .func_log = dbg_log, + .func_audit = NULL +}; +static const struct avc_thread_callback thread_cb = +{ + .func_create_thread = avc_create_thread, + .func_stop_thread = avc_stop_thread +}; +static const struct avc_lock_callback lock_cb = +{ + .func_alloc_lock = avc_alloc_lock, + .func_get_lock = avc_get_lock, + .func_release_lock = avc_release_lock, + .func_free_lock = avc_free_lock +}; + + +/* Determine if we are running on an SELinux kernel. Set selinux_enabled + to the result. */ +void +nscd_selinux_enabled (int *selinux_enabled) +{ + *selinux_enabled = is_selinux_enabled (); + if (*selinux_enabled < 0) + { + dbg_log (_("Failed to determine if kernel supports SELinux")); + exit (EXIT_FAILURE); + } +} + + +/* Create thread for AVC netlink notification. */ +static void * +avc_create_thread (void (*run) (void)) +{ + int rc; + + rc = + pthread_create (&avc_notify_thread, NULL, (void *(*) (void *)) run, NULL); + if (rc != 0) + error (EXIT_FAILURE, rc, _("Failed to start AVC thread")); + + return &avc_notify_thread; +} + + +/* Stop AVC netlink thread. */ +static void +avc_stop_thread (void *thread) +{ + pthread_cancel (*(pthread_t *) thread); +} + + +/* Allocate a new AVC lock. */ +static void * +avc_alloc_lock (void) +{ + pthread_mutex_t *avc_mutex; + + avc_mutex = malloc (sizeof (pthread_mutex_t)); + if (avc_mutex == NULL) + error (EXIT_FAILURE, errno, _("Failed to create AVC lock")); + pthread_mutex_init (avc_mutex, NULL); + + return avc_mutex; +} + + +/* Acquire an AVC lock. */ +static void +avc_get_lock (void *lock) +{ + pthread_mutex_lock (lock); +} + + +/* Release an AVC lock. */ +static void +avc_release_lock (void *lock) +{ + pthread_mutex_unlock (lock); +} + + +/* Free an AVC lock. */ +static void +avc_free_lock (void *lock) +{ + pthread_mutex_destroy (lock); + free (lock); +} + + +/* Initialize the user space access vector cache (AVC) for NSCD along with + log/thread/lock callbacks. */ +void +nscd_avc_init (void) +{ + avc_entry_ref_init (&aeref); + + if (avc_init ("avc", NULL, &log_cb, &thread_cb, &lock_cb) < 0) + error (EXIT_FAILURE, errno, _("Failed to start AVC")); + else + dbg_log (_("Access Vector Cache (AVC) started")); +} + + +/* Check the permission from the caller (via getpeercon) to nscd. + Returns 0 if access is allowed, 1 if denied, and -1 on error. */ +int +nscd_request_avc_has_perm (int fd, request_type req) +{ + /* Initialize to NULL so we know what to free in case of failure. */ + security_context_t scon = NULL; + security_context_t tcon = NULL; + security_id_t ssid = NULL; + security_id_t tsid = NULL; + int rc = -1; + + if (getpeercon (fd, &scon) < 0) + { + dbg_log (_("Error getting context of socket peer")); + goto out; + } + if (getcon (&tcon) < 0) + { + dbg_log (_("Error getting context of nscd")); + goto out; + } + if (avc_context_to_sid (scon, &ssid) < 0 || + avc_context_to_sid (tcon, &tsid) < 0) + { + dbg_log (_("Error getting sid from context")); + goto out; + } + + rc = avc_has_perm (ssid, tsid, SECCLASS_NSCD, perms[req], &aeref, NULL) < 0; + +out: + if (scon) + freecon (scon); + if (tcon) + freecon (tcon); + if (ssid) + sidput (ssid); + if (tsid) + sidput (tsid); + + return rc; +} + + +/* Wrapper to get AVC statistics. */ +void +nscd_avc_cache_stats (struct avc_cache_stats *cstats) +{ + avc_cache_stats (cstats); +} + + +/* Print the AVC statistics to stdout. */ +void +nscd_avc_print_stats (struct avc_cache_stats *cstats) +{ + printf (_("\nSELinux AVC Statistics:\n\n" + "%15u entry lookups\n" + "%15u entry hits\n" + "%15u entry misses\n" + "%15u entry discards\n" + "%15u CAV lookups\n" + "%15u CAV hits\n" + "%15u CAV probes\n" + "%15u CAV misses\n"), + cstats->entry_lookups, cstats->entry_hits, cstats->entry_misses, + cstats->entry_discards, cstats->cav_lookups, cstats->cav_hits, + cstats->cav_probes, cstats->cav_misses); +} + + +/* Clean up the AVC before exiting. */ +void +nscd_avc_destroy (void) +{ + avc_destroy (); +} + +#endif /* HAVE_SELINUX */ diff --git a/nscd/selinux.h b/nscd/selinux.h new file mode 100644 index 0000000000..b9eb053aa0 --- /dev/null +++ b/nscd/selinux.h @@ -0,0 +1,55 @@ +/* Header for nscd SELinux access controls. + Copyright (C) 2004 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Matthew Rickard <mjricka@epoch.ncsc.mil>, 2004. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#ifndef _SELINUX_H +#define _SELINUX_H 1 + +#include "nscd.h" + +#ifdef HAVE_SELINUX +/* Global variable to tell if the kernel has SELinux support. */ +extern int selinux_enabled; + +/* Define this for AVC stat usage. */ +struct avc_cache_stats; + +/* Initialize the userspace AVC. */ +extern void nscd_avc_init (void); +/* Destroy the userspace AVC. */ +extern void nscd_avc_destroy (void); +/* Determine if we are running on an SELinux kernel. */ +extern void nscd_selinux_enabled (int *selinux_enabled); +/* Check if the client has permission for the request type. */ +extern int nscd_request_avc_has_perm (int fd, request_type req); +/* Initialize AVC statistic information. */ +extern void nscd_avc_cache_stats (struct avc_cache_stats *cstats); +/* Display statistics on AVC usage. */ +extern void nscd_avc_print_stats (struct avc_cache_stats *cstats); +#else +# define selinux_enabled 0 +# define nscd_avc_init() (void) 0 +# define nscd_avc_destroy() (void) 0 +# define nscd_selinux_enabled(selinux_enabled) (void) 0 +# define nscd_request_avc_has_perm(fd, req) 0 +# define nscd_avc_cache_stats(cstats) (void) 0 +# define nscd_avc_print_stats(cstats) (void) 0 +#endif /* HAVE_SELINUX */ + +#endif /* _SELINUX_H */ |