[systemd-devel] [PATCH v3 2/2] syscallfilter: port to libseccomp

Ronny Chevalier chevalier.ronny at gmail.com
Tue Feb 11 16:29:54 PST 2014


---
Ok so I found the problem. I forgot a condition in SET_FOREACH that if e is 0, it will stop the foreach (and read have the id 0)

Here is the new patch fixing this. Sorry again

 Makefile.am                    | 30 ++-----------
 README                         |  1 +
 TODO                           |  1 -
 configure.ac                   | 14 ++++++
 man/systemd.exec.xml           | 18 +++++++-
 src/core/build.h               |  8 +++-
 src/core/dbus-execute.c        |  8 +---
 src/core/execute.c             | 88 ++++++++++++++++++--------------------
 src/core/execute.h             | 12 +++++-
 src/core/load-fragment.c       | 96 +++++++++++++++++++++++++++---------------
 src/shared/.gitignore          |  4 --
 src/shared/linux/seccomp-bpf.h | 76 ---------------------------------
 src/shared/linux/seccomp.h     | 47 ---------------------
 src/shared/syscall-list.c      | 56 ------------------------
 src/shared/syscall-list.h      | 41 ------------------
 src/test/test-tables.c         |  3 --
 16 files changed, 157 insertions(+), 346 deletions(-)
 delete mode 100644 src/shared/linux/seccomp-bpf.h
 delete mode 100644 src/shared/linux/seccomp.h
 delete mode 100644 src/shared/syscall-list.c
 delete mode 100644 src/shared/syscall-list.h

diff --git a/Makefile.am b/Makefile.am
index 6a3fd48..1b978e5 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -653,8 +653,6 @@ noinst_LTLIBRARIES += \
 libsystemd_shared_la_SOURCES = \
 	src/shared/linux/auto_dev-ioctl.h \
 	src/shared/linux/fanotify.h \
-	src/shared/linux/seccomp.h \
-	src/shared/linux/seccomp-bpf.h \
 	src/shared/ioprio.h \
 	src/shared/missing.h \
 	src/shared/initreq.h \
@@ -762,8 +760,6 @@ libsystemd_shared_la_SOURCES = \
 	src/shared/net-util.h \
 	src/shared/errno-list.c \
 	src/shared/errno-list.h \
-	src/shared/syscall-list.c \
-	src/shared/syscall-list.h \
 	src/shared/audit.c \
 	src/shared/audit.h \
 	src/shared/xml.c \
@@ -771,9 +767,7 @@ libsystemd_shared_la_SOURCES = \
 
 nodist_libsystemd_shared_la_SOURCES = \
 	src/shared/errno-from-name.h \
-	src/shared/errno-to-name.h \
-	src/shared/syscall-from-name.h \
-	src/shared/syscall-to-name.h
+	src/shared/errno-to-name.h
 
 # ------------------------------------------------------------------------------
 noinst_LTLIBRARIES += \
@@ -998,6 +992,7 @@ libsystemd_core_la_CFLAGS = \
 	$(PAM_CFLAGS) \
 	$(AUDIT_CFLAGS) \
 	$(KMOD_CFLAGS) \
+	$(SECCOMP_CFLAGS) \
 	-pthread
 
 libsystemd_core_la_LIBADD = \
@@ -1012,6 +1007,7 @@ libsystemd_core_la_LIBADD = \
 	$(PAM_LIBS) \
 	$(AUDIT_LIBS) \
 	$(CAP_LIBS) \
+	$(SECCOMP_LIBS) \
 	$(KMOD_LIBS)
 
 src/core/load-fragment-gperf-nulstr.c: src/core/load-fragment-gperf.gperf
@@ -1025,33 +1021,13 @@ CLEANFILES += \
 	src/core/load-fragment-gperf.gperf \
 	src/core/load-fragment-gperf.c \
 	src/core/load-fragment-gperf-nulstr.c \
-	src/shared/syscall-list.txt \
-	src/shared/syscall-from-name.gperf \
 	src/shared/errno-list.txt \
 	src/shared/errno-from-name.gperf
 
 BUILT_SOURCES += \
-	src/shared/syscall-from-name.h \
-	src/shared/syscall-to-name.h \
 	src/shared/errno-from-name.h \
 	src/shared/errno-to-name.h
 
-src/shared/syscall-list.txt:
-	$(AM_V_at)$(MKDIR_P) $(dir $@)
-	$(AM_V_GEN)$(CPP) $(CFLAGS) $(AM_CPPFLAGS) $(CPPFLAGS) -dM -include sys/syscall.h - < /dev/null | $(AWK) '/^#define[ \t]+__NR_[^ ]+[ \t]+[0-9(]/ { sub(/__NR_/, "", $$2); if ($$2 !~ /SYSCALL_BASE/) print $$2; }' > $@
-
-src/shared/syscall-from-name.gperf: src/shared/syscall-list.txt
-	$(AM_V_at)$(MKDIR_P) $(dir $@)
-	$(AM_V_GEN)$(AWK) 'BEGIN{ print "struct syscall_name { const char* name; int id; };"; print "%null-strings"; print "%%";} { printf "%s, __NR_%s\n", $$1, $$1 }' < $< > $@
-
-src/shared/syscall-from-name.h: src/shared/syscall-from-name.gperf
-	$(AM_V_at)$(MKDIR_P) $(dir $@)
-	$(AM_V_GPERF)$(GPERF) -L ANSI-C -t --ignore-case -N lookup_syscall -H hash_syscall_name -p -C < $< > $@
-
-src/shared/syscall-to-name.h: src/shared/syscall-list.txt
-	$(AM_V_at)$(MKDIR_P) $(dir $@)
-	$(AM_V_GEN)$(AWK) 'BEGIN{ print "static const char* const syscall_names[] = { "} { printf "[SYSCALL_TO_INDEX(__NR_%s)] = \"%s\",\n", $$1, $$1 } END{print "};"}' < $< > $@
-
 src/shared/errno-list.txt:
 	$(AM_V_at)$(MKDIR_P) $(dir $@)
 	$(AM_V_GEN)$(CPP) $(CFLAGS) $(AM_CPPFLAGS) $(CPPFLAGS) -dM -include errno.h - < /dev/null | $(AWK) '/^#define[ \t]+E[^ _]+[ \t]+[0-9]/ { print $$2; }'  > $@
diff --git a/README b/README
index 509b45f..a237672 100644
--- a/README
+++ b/README
@@ -92,6 +92,7 @@ REQUIREMENTS:
 
         glibc >= 2.14
         libcap
+        libseccomp >= 1.0.0 (optional)
         libblkid >= 2.20 (from util-linux) (optional)
         libkmod >= 15 (optional)
         PAM >= 1.1.2 (optional)
diff --git a/TODO b/TODO
index fd2cfcb..220b6ee 100644
--- a/TODO
+++ b/TODO
@@ -503,7 +503,6 @@ Features:
   - syscall filter: add knowledge about compat syscalls
   - syscall filter: don't enforce no new privs?
   - syscall filter: option to return EPERM rather than SIGSYS?
-  - syscall filter: port to libseccomp
   - system-wide seccomp filter
 
 * load-fragment: when loading a unit file via a chain of symlinks
diff --git a/configure.ac b/configure.ac
index d92f1fe..940ae9f 100644
--- a/configure.ac
+++ b/configure.ac
@@ -321,6 +321,19 @@ fi
 AM_CONDITIONAL(HAVE_BLKID, [test "$have_blkid" = "yes"])
 
 # ------------------------------------------------------------------------------
+have_seccomp=no
+AC_ARG_ENABLE(seccomp, AS_HELP_STRING([--disable-seccomp], [Disable optional SECCOMP support]))
+if test "x$enable_seccomp" != "xno"; then
+        PKG_CHECK_MODULES(SECCOMP, [libseccomp >= 1.0.0],
+               [AC_DEFINE(HAVE_SECCOMP, 1, [Define if seccomp is available]) have_seccomp=yes],
+               [have_seccomp=no])
+        if test "x$have_seccomp" = "xno" -a "x$enable_seccomp" = "xyes"; then
+                AC_MSG_ERROR([*** seccomp support requested but libraries not found])
+        fi
+fi
+AM_CONDITIONAL(HAVE_SECCOMP, [test "$have_seccomp" = "yes"])
+
+# ------------------------------------------------------------------------------
 have_ima=yes
 AC_ARG_ENABLE([ima], AS_HELP_STRING([--disable-ima],[Disable optional IMA support]),
                 [case "${enableval}" in
@@ -1088,6 +1101,7 @@ AC_MSG_RESULT([
         AUDIT:                   ${have_audit}
         IMA:                     ${have_ima}
         SELinux:                 ${have_selinux}
+        SECCOMP:                 ${have_seccomp}
         SMACK:                   ${have_smack}
         XZ:                      ${have_xz}
         ACL:                     ${have_acl}
diff --git a/man/systemd.exec.xml b/man/systemd.exec.xml
index f4caccd..0c6ca5a 100644
--- a/man/systemd.exec.xml
+++ b/man/systemd.exec.xml
@@ -1029,7 +1029,23 @@
                                 merged. If the empty string is
                                 assigned, the filter is reset, all
                                 prior assignments will have no
-                                effect.</para></listitem>
+                                effect.</para>
+
+                                <para>If you specify both types of this option
+                                (i.e. whitelisting and blacklisting) the first
+                                encountered will take precedence and will
+                                dictate the default action (termination
+                                or approval of a system call). Then the
+                                next occurrences of this option will add or
+                                delete the listed system calls from the set
+                                of the filtered system calls, depending of
+                                its type and the default action (e.g. You
+                                have started with a whitelisting of <function>
+                                read</function> and <function>write</function>
+                                and right after it add a blacklisting of
+                                <function>write</function>, then <function>
+                                write</function> will be removed from the set)
+                                </para></listitem>
                         </varlistentry>
 
                 </variablelist>
diff --git a/src/core/build.h b/src/core/build.h
index 4513a0b..f04f03f 100644
--- a/src/core/build.h
+++ b/src/core/build.h
@@ -81,4 +81,10 @@
 #define _XZ_FEATURE_ "-XZ"
 #endif
 
-#define SYSTEMD_FEATURES _PAM_FEATURE_ " " _LIBWRAP_FEATURE_ " " _AUDIT_FEATURE_ " " _SELINUX_FEATURE_ " " _IMA_FEATURE_ " " _SYSVINIT_FEATURE_ " " _LIBCRYPTSETUP_FEATURE_ " " _GCRYPT_FEATURE_ " " _ACL_FEATURE_ " " _XZ_FEATURE_
+#ifdef HAVE_SECCOMP
+#define _SECCOMP_FEATURE_ "+SECCOMP"
+#else
+#define _SECCOMP_FEATURE_ "-SECCOMP"
+#endif
+
+#define SYSTEMD_FEATURES _PAM_FEATURE_ " " _LIBWRAP_FEATURE_ " " _AUDIT_FEATURE_ " " _SELINUX_FEATURE_ " " _IMA_FEATURE_ " " _SYSVINIT_FEATURE_ " " _LIBCRYPTSETUP_FEATURE_ " " _GCRYPT_FEATURE_ " " _ACL_FEATURE_ " " _XZ_FEATURE_ _SECCOMP_FEATURE_
diff --git a/src/core/dbus-execute.c b/src/core/dbus-execute.c
index db16990..2ed7a3c 100644
--- a/src/core/dbus-execute.c
+++ b/src/core/dbus-execute.c
@@ -25,7 +25,6 @@
 #include "missing.h"
 #include "ioprio.h"
 #include "strv.h"
-#include "syscall-list.h"
 #include "fileio.h"
 #include "execute.h"
 #include "dbus-execute.h"
@@ -354,10 +353,7 @@ static int property_get_syscall_filter(
         assert(reply);
         assert(c);
 
-        if (c->syscall_filter)
-                return sd_bus_message_append_array(reply, 'u', c->syscall_filter, (syscall_max() + 31) >> 4);
-        else
-                return sd_bus_message_append_array(reply, 'u', NULL, 0);
+        return sd_bus_message_append(reply, "s", c->syscall_filter_string);
 }
 
 const sd_bus_vtable bus_exec_vtable[] = {
@@ -422,7 +418,7 @@ const sd_bus_vtable bus_exec_vtable[] = {
         SD_BUS_PROPERTY("SELinuxContext", "s", NULL, offsetof(ExecContext, selinux_context), SD_BUS_VTABLE_PROPERTY_CONST),
         SD_BUS_PROPERTY("IgnoreSIGPIPE", "b", bus_property_get_bool, offsetof(ExecContext, ignore_sigpipe), SD_BUS_VTABLE_PROPERTY_CONST),
         SD_BUS_PROPERTY("NoNewPrivileges", "b", bus_property_get_bool, offsetof(ExecContext, no_new_privileges), SD_BUS_VTABLE_PROPERTY_CONST),
-        SD_BUS_PROPERTY("SystemCallFilter", "au", property_get_syscall_filter, 0, SD_BUS_VTABLE_PROPERTY_CONST),
+        SD_BUS_PROPERTY("SystemCallFilter", "s", property_get_syscall_filter, 0, SD_BUS_VTABLE_PROPERTY_CONST),
         SD_BUS_VTABLE_END
 };
 
diff --git a/src/core/execute.c b/src/core/execute.c
index b941a02..d2e5b74 100644
--- a/src/core/execute.c
+++ b/src/core/execute.c
@@ -38,9 +38,13 @@
 #include <linux/fs.h>
 #include <linux/oom.h>
 #include <sys/poll.h>
-#include <linux/seccomp-bpf.h>
 #include <glob.h>
 #include <libgen.h>
+#ifdef HAVE_SECCOMP
+#include <seccomp.h>
+
+#include "set.h"
+#endif
 #undef basename
 
 #ifdef HAVE_PAM
@@ -67,7 +71,6 @@
 #include "utmp-wtmp.h"
 #include "def.h"
 #include "path-util.h"
-#include "syscall-list.h"
 #include "env-util.h"
 #include "fileio.h"
 #include "unit.h"
@@ -933,57 +936,32 @@ static void rename_process_from_path(const char *path) {
         rename_process(process_name);
 }
 
-static int apply_seccomp(uint32_t *syscall_filter) {
-        static const struct sock_filter header[] = {
-                VALIDATE_ARCHITECTURE,
-                EXAMINE_SYSCALL
-        };
-        static const struct sock_filter footer[] = {
-                _KILL_PROCESS
-        };
-
-        int i;
-        unsigned n;
-        struct sock_filter *f;
-        struct sock_fprog prog = {};
-
-        assert(syscall_filter);
+#ifdef HAVE_SECCOMP
+static int apply_seccomp(ExecContext *c) {
+        uint32_t action = SCMP_ACT_ALLOW;
+        Iterator i;
+        void *id;
 
-        /* First: count the syscalls to check for */
-        for (i = 0, n = 0; i < syscall_max(); i++)
-                if (syscall_filter[i >> 4] & (1 << (i & 31)))
-                        n++;
-
-        /* Second: build the filter program from a header the syscall
-         * matches and the footer */
-        f = alloca(sizeof(struct sock_filter) * (ELEMENTSOF(header) + 2*n + ELEMENTSOF(footer)));
-        memcpy(f, header, sizeof(header));
-
-        for (i = 0, n = 0; i < syscall_max(); i++)
-                if (syscall_filter[i >> 4] & (1 << (i & 31))) {
-                        struct sock_filter item[] = {
-                                BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, INDEX_TO_SYSCALL(i), 0, 1),
-                                BPF_STMT(BPF_RET+BPF_K, SECCOMP_RET_ALLOW)
-                        };
+        assert(c);
 
-                        assert_cc(ELEMENTSOF(item) == 2);
+        c->syscall_filter = seccomp_init(c->syscall_filter_default_action);
+        if (!c->syscall_filter)
+                return -1;
 
-                        f[ELEMENTSOF(header) + 2*n]  = item[0];
-                        f[ELEMENTSOF(header) + 2*n+1] = item[1];
+        if (c->syscall_filter_default_action == SCMP_ACT_ALLOW)
+                action = SCMP_ACT_KILL;
 
-                        n++;
+        SET_FOREACH(id, c->filtered_syscalls, i) {
+                int r = seccomp_rule_add(c->syscall_filter, action, PTR_TO_INT(id) - 1, 0);
+                if (r < 0) {
+                        log_error("Failed to add syscall filter");
+                        return r;
                 }
+        }
 
-        memcpy(f + (ELEMENTSOF(header) + 2*n), footer, sizeof(footer));
-
-        /* Third: install the filter */
-        prog.len = ELEMENTSOF(header) + ELEMENTSOF(footer) + 2*n;
-        prog.filter = f;
-        if (prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog) < 0)
-                return -errno;
-
-        return 0;
+        return seccomp_load(c->syscall_filter);
 }
+#endif
 
 static void do_idle_pipe_dance(int idle_pipe[4]) {
         assert(idle_pipe);
@@ -1562,13 +1540,15 @@ int exec_spawn(ExecCommand *command,
                                         goto fail_child;
                                 }
 
-                        if (context->syscall_filter) {
-                                err = apply_seccomp(context->syscall_filter);
+#ifdef HAVE_SECCOMP
+                        if (context->filtered_syscalls) {
+                                err = apply_seccomp(context);
                                 if (err < 0) {
                                         r = EXIT_SECCOMP;
                                         goto fail_child;
                                 }
                         }
+#endif
 #ifdef HAVE_SELINUX
                         if (context->selinux_context && use_selinux()) {
                                 bool ignore;
@@ -1751,6 +1731,18 @@ void exec_context_done(ExecContext *c) {
 
         free(c->syscall_filter);
         c->syscall_filter = NULL;
+
+        free(c->syscall_filter_string);
+        c->syscall_filter_string = NULL;
+
+#ifdef HAVE_SECCOMP
+        if (c->syscall_filter) {
+                seccomp_release(c->syscall_filter);
+                c->syscall_filter = NULL;
+        }
+        set_free(c->filtered_syscalls);
+        c->filtered_syscalls = NULL;
+#endif
 }
 
 void exec_command_done(ExecCommand *c) {
diff --git a/src/core/execute.h b/src/core/execute.h
index be811a9..b2d70d7 100644
--- a/src/core/execute.h
+++ b/src/core/execute.h
@@ -33,6 +33,11 @@ typedef struct ExecRuntime ExecRuntime;
 #include <stdbool.h>
 #include <stdio.h>
 #include <sched.h>
+#ifdef HAVE_SECCOMP
+#include <seccomp.h>
+
+#include "set.h"
+#endif
 
 #include "list.h"
 #include "util.h"
@@ -162,7 +167,12 @@ struct ExecContext {
          * don't enter a trigger loop. */
         bool same_pgrp;
 
-        uint32_t *syscall_filter;
+#ifdef HAVE_SECCOMP
+        scmp_filter_ctx syscall_filter;
+        Set *filtered_syscalls;
+        uint32_t syscall_filter_default_action;
+#endif
+        char *syscall_filter_string;
 
         bool oom_score_adjust_set:1;
         bool nice_set:1;
diff --git a/src/core/load-fragment.c b/src/core/load-fragment.c
index 7a2d32d..06ff18b 100644
--- a/src/core/load-fragment.c
+++ b/src/core/load-fragment.c
@@ -33,6 +33,11 @@
 #include <sys/stat.h>
 #include <sys/time.h>
 #include <sys/resource.h>
+#ifdef HAVE_SECCOMP
+#include <seccomp.h>
+
+#include "set.h"
+#endif
 
 #include "sd-messages.h"
 #include "unit.h"
@@ -47,13 +52,12 @@
 #include "unit-printf.h"
 #include "utf8.h"
 #include "path-util.h"
-#include "syscall-list.h"
 #include "env-util.h"
 #include "cgroup.h"
 #include "bus-util.h"
 #include "bus-error.h"
 
-#ifndef HAVE_SYSV_COMPAT
+#if !defined(HAVE_SYSV_COMPAT) || !defined(HAVE_SECCOMP)
 int config_parse_warn_compat(const char *unit,
                              const char *filename,
                              unsigned line,
@@ -1916,16 +1920,7 @@ int config_parse_documentation(const char *unit,
         return r;
 }
 
-static void syscall_set(uint32_t *p, int nr) {
-        nr = SYSCALL_TO_INDEX(nr);
-        p[nr >> 4] |= 1 << (nr & 31);
-}
-
-static void syscall_unset(uint32_t *p, int nr) {
-        nr = SYSCALL_TO_INDEX(nr);
-        p[nr >> 4] &= ~(1 << (nr & 31));
-}
-
+#ifdef HAVE_SECCOMP
 int config_parse_syscall_filter(const char *unit,
                                 const char *filename,
                                 unsigned line,
@@ -1936,13 +1931,23 @@ int config_parse_syscall_filter(const char *unit,
                                 const char *rvalue,
                                 void *data,
                                 void *userdata) {
-
         ExecContext *c = data;
         Unit *u = userdata;
         bool invert = false;
         char *w;
         size_t l;
         char *state;
+        _cleanup_strv_free_ char **syscalls = strv_new(NULL, NULL);
+        _cleanup_free_ char *sorted_syscalls = NULL;
+        uint32_t action = SCMP_ACT_ALLOW;
+        Iterator i;
+        void *e;
+        static char const *default_syscalls[] = {"execve",
+                                                 "exit",
+                                                 "exit_group",
+                                                 "rt_sigreturn",
+                                                 "sigreturn",
+                                                 NULL};
 
         assert(filename);
         assert(lvalue);
@@ -1951,34 +1956,37 @@ int config_parse_syscall_filter(const char *unit,
 
         if (isempty(rvalue)) {
                 /* Empty assignment resets the list */
-                free(c->syscall_filter);
-                c->syscall_filter = NULL;
+                set_free(c->filtered_syscalls);
+                c->filtered_syscalls= NULL;
+                free(c->syscall_filter_string);
+                c->syscall_filter_string = NULL;
                 return 0;
         }
 
         if (rvalue[0] == '~') {
                 invert = true;
+                action = SCMP_ACT_KILL;
                 rvalue++;
         }
 
-        if (!c->syscall_filter) {
-                size_t n;
+        if (!c->filtered_syscalls) {
+                c->filtered_syscalls = set_new(trivial_hash_func, trivial_compare_func);
+                if (invert)
+                        c->syscall_filter_default_action = SCMP_ACT_ALLOW;
+                else {
+                        char const **syscall;
 
-                n = (syscall_max() + 31) >> 4;
-                c->syscall_filter = new(uint32_t, n);
-                if (!c->syscall_filter)
-                        return log_oom();
+                        c->syscall_filter_default_action = SCMP_ACT_KILL;
 
-                memset(c->syscall_filter, invert ? 0xFF : 0, n * sizeof(uint32_t));
+                        /* accept default syscalls if we are on a whitelist */
+                        STRV_FOREACH(syscall, default_syscalls) {
+                                int id = seccomp_syscall_resolve_name(*syscall);
+                                if (id < 0)
+                                        continue;
 
-                /* Add these by default */
-                syscall_set(c->syscall_filter, __NR_execve);
-                syscall_set(c->syscall_filter, __NR_rt_sigreturn);
-#ifdef __NR_sigreturn
-                syscall_set(c->syscall_filter, __NR_sigreturn);
-#endif
-                syscall_set(c->syscall_filter, __NR_exit_group);
-                syscall_set(c->syscall_filter, __NR_exit);
+                                set_replace(c->filtered_syscalls, INT_TO_PTR(id + 1));
+                        }
+                }
         }
 
         FOREACH_WORD_QUOTED(w, l, rvalue, state) {
@@ -1989,23 +1997,39 @@ int config_parse_syscall_filter(const char *unit,
                 if (!t)
                         return log_oom();
 
-                id = syscall_from_name(t);
+                id = seccomp_syscall_resolve_name(t);
                 if (id < 0)  {
                         log_syntax(unit, LOG_ERR, filename, line, EINVAL,
                                    "Failed to parse syscall, ignoring: %s", t);
                         continue;
                 }
 
-                if (invert)
-                        syscall_unset(c->syscall_filter, id);
+                /* If we previously wanted to forbid a syscall
+                 * and now we want to allow it, then remove it from the list
+                 * libseccomp will also return -EPERM if we try to add
+                 * a rule with the same action as the default
+                 */
+                if (action == c->syscall_filter_default_action)
+                        set_remove(c->filtered_syscalls, INT_TO_PTR(id + 1));
                 else
-                        syscall_set(c->syscall_filter, id);
+                        set_replace(c->filtered_syscalls, INT_TO_PTR(id + 1));
+        }
+
+        SET_FOREACH(e, c->filtered_syscalls, i) {
+                char *name = seccomp_syscall_resolve_num_arch(SCMP_ARCH_NATIVE, PTR_TO_INT(e) - 1);
+                strv_push(&syscalls, name);
         }
 
+        sorted_syscalls = strv_join(strv_sort(syscalls), " ");
+        if (invert)
+                c->syscall_filter_string = strv_join(STRV_MAKE("~", sorted_syscalls, NULL), "");
+        else
+                c->syscall_filter_string = strdup(sorted_syscalls);
         c->no_new_privileges = true;
 
         return 0;
 }
+#endif
 
 int config_parse_unit_slice(
                 const char *unit,
@@ -2778,7 +2802,11 @@ void unit_dump_config_items(FILE *f) {
                 { config_parse_set_status,            "STATUS" },
                 { config_parse_service_sockets,       "SOCKETS" },
                 { config_parse_environ,               "ENVIRON" },
+#ifdef HAVE_SECCOMP
                 { config_parse_syscall_filter,        "SYSCALL" },
+#else
+                { config_parse_warn_compat,           "NOTSUPPORTED" },
+#endif
                 { config_parse_cpu_shares,            "SHARES" },
                 { config_parse_memory_limit,          "LIMIT" },
                 { config_parse_device_allow,          "DEVICE" },
diff --git a/src/shared/.gitignore b/src/shared/.gitignore
index 3820d19..c9b5f81 100644
--- a/src/shared/.gitignore
+++ b/src/shared/.gitignore
@@ -1,7 +1,3 @@
-/syscall-from-name.gperf
-/syscall-from-name.h
-/syscall-list.txt
-/syscall-to-name.h
 /errno-from-name.gperf
 /errno-from-name.h
 /errno-list.txt
diff --git a/src/shared/linux/seccomp-bpf.h b/src/shared/linux/seccomp-bpf.h
deleted file mode 100644
index 1e3d136..0000000
--- a/src/shared/linux/seccomp-bpf.h
+++ /dev/null
@@ -1,76 +0,0 @@
-/*
- * seccomp example for x86 (32-bit and 64-bit) with BPF macros
- *
- * Copyright (c) 2012 The Chromium OS Authors <chromium-os-dev at chromium.org>
- * Authors:
- *  Will Drewry <wad at chromium.org>
- *  Kees Cook <keescook at chromium.org>
- *
- * The code may be used by anyone for any purpose, and can serve as a
- * starting point for developing applications using mode 2 seccomp.
- */
-#ifndef _SECCOMP_BPF_H_
-#define _SECCOMP_BPF_H_
-
-#include <stdio.h>
-#include <stddef.h>
-#include <stdlib.h>
-#include <errno.h>
-#include <signal.h>
-#include <string.h>
-#include <unistd.h>
-
-#include <sys/prctl.h>
-
-#include <linux/unistd.h>
-#include <linux/audit.h>
-#include <linux/filter.h>
-#include <linux/seccomp.h>
-
-#ifndef SECCOMP_MODE_FILTER
-# define SECCOMP_MODE_FILTER	2 /* uses user-supplied filter. */
-# define SECCOMP_RET_KILL	0x00000000U /* kill the task immediately */
-# define SECCOMP_RET_TRAP	0x00030000U /* disallow and force a SIGSYS */
-# define SECCOMP_RET_ALLOW	0x7fff0000U /* allow */
-struct seccomp_data {
-    int nr;
-    __u32 arch;
-    __u64 instruction_pointer;
-    __u64 args[6];
-};
-#endif
-#ifndef SYS_SECCOMP
-# define SYS_SECCOMP 1
-#endif
-
-#define syscall_nr (offsetof(struct seccomp_data, nr))
-#define arch_nr (offsetof(struct seccomp_data, arch))
-
-#if defined(__i386__)
-# define REG_SYSCALL	REG_EAX
-# define ARCH_NR	AUDIT_ARCH_I386
-#elif defined(__x86_64__)
-# define REG_SYSCALL	REG_RAX
-# define ARCH_NR	AUDIT_ARCH_X86_64
-#else
-# warning "Platform does not support seccomp filter yet"
-# define REG_SYSCALL	0
-# define ARCH_NR	0
-#endif
-
-#define VALIDATE_ARCHITECTURE \
-	BPF_STMT(BPF_LD+BPF_W+BPF_ABS, arch_nr), \
-	BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, ARCH_NR, 1, 0), \
-	BPF_STMT(BPF_RET+BPF_K, SECCOMP_RET_KILL)
-
-#define EXAMINE_SYSCALL \
-	BPF_STMT(BPF_LD+BPF_W+BPF_ABS, syscall_nr)
-
-#define ALLOW_SYSCALL(name) \
-	BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, __NR_##name, 0, 1), \
-	BPF_STMT(BPF_RET+BPF_K, SECCOMP_RET_ALLOW)
-
-#define _KILL_PROCESS \
-	BPF_STMT(BPF_RET+BPF_K, SECCOMP_RET_KILL)
-
-#endif /* _SECCOMP_BPF_H_ */
diff --git a/src/shared/linux/seccomp.h b/src/shared/linux/seccomp.h
deleted file mode 100644
index 9c03683..0000000
--- a/src/shared/linux/seccomp.h
+++ /dev/null
@@ -1,47 +0,0 @@
-#ifndef _LINUX_SECCOMP_H
-#define _LINUX_SECCOMP_H
-
-
-#include <linux/types.h>
-
-
-/* Valid values for seccomp.mode and prctl(PR_SET_SECCOMP, <mode>) */
-#define SECCOMP_MODE_DISABLED	0 /* seccomp is not in use. */
-#define SECCOMP_MODE_STRICT	1 /* uses hard-coded filter. */
-#define SECCOMP_MODE_FILTER	2 /* uses user-supplied filter. */
-
-/*
- * All BPF programs must return a 32-bit value.
- * The bottom 16-bits are for optional return data.
- * The upper 16-bits are ordered from least permissive values to most.
- *
- * The ordering ensures that a min_t() over composed return values always
- * selects the least permissive choice.
- */
-#define SECCOMP_RET_KILL	0x00000000U /* kill the task immediately */
-#define SECCOMP_RET_TRAP	0x00030000U /* disallow and force a SIGSYS */
-#define SECCOMP_RET_ERRNO	0x00050000U /* returns an errno */
-#define SECCOMP_RET_TRACE	0x7ff00000U /* pass to a tracer or disallow */
-#define SECCOMP_RET_ALLOW	0x7fff0000U /* allow */
-
-/* Masks for the return value sections. */
-#define SECCOMP_RET_ACTION	0x7fff0000U
-#define SECCOMP_RET_DATA	0x0000ffffU
-
-/**
- * struct seccomp_data - the format the BPF program executes over.
- * @nr: the system call number
- * @arch: indicates system call convention as an AUDIT_ARCH_* value
- *        as defined in <linux/audit.h>.
- * @instruction_pointer: at the time of the system call.
- * @args: up to 6 system call arguments always stored as 64-bit values
- *        regardless of the architecture.
- */
-struct seccomp_data {
-	int nr;
-	__u32 arch;
-	__u64 instruction_pointer;
-	__u64 args[6];
-};
-
-#endif /* _LINUX_SECCOMP_H */
diff --git a/src/shared/syscall-list.c b/src/shared/syscall-list.c
deleted file mode 100644
index dc84dca..0000000
--- a/src/shared/syscall-list.c
+++ /dev/null
@@ -1,56 +0,0 @@
-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
-/***
-  This file is part of systemd.
-
-  Copyright 2012 Lennart Poettering
-
-  systemd 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.
-
-  systemd 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 systemd; If not, see <http://www.gnu.org/licenses/>.
-***/
-
-#include <sys/syscall.h>
-#include <string.h>
-
-#include "util.h"
-#include "syscall-list.h"
-
-static const struct syscall_name* lookup_syscall(register const char *str,
-                                                 register unsigned int len);
-
-#include "syscall-to-name.h"
-#include "syscall-from-name.h"
-
-const char *syscall_to_name(int id) {
-        id = SYSCALL_TO_INDEX(id);
-        if (id < 0 || id >= (int) ELEMENTSOF(syscall_names))
-                return NULL;
-
-        return syscall_names[id];
-}
-
-int syscall_from_name(const char *name) {
-        const struct syscall_name *sc;
-
-        assert(name);
-
-        sc = lookup_syscall(name, strlen(name));
-        if (!sc)
-                return -1;
-
-        return sc->id;
-}
-
-int syscall_max(void) {
-        return ELEMENTSOF(syscall_names);
-}
diff --git a/src/shared/syscall-list.h b/src/shared/syscall-list.h
deleted file mode 100644
index 37efc56..0000000
--- a/src/shared/syscall-list.h
+++ /dev/null
@@ -1,41 +0,0 @@
-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
-#pragma once
-
-/***
-  This file is part of systemd.
-
-  Copyright 2012 Lennart Poettering
-
-  systemd 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.
-
-  systemd 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 systemd; If not, see <http://www.gnu.org/licenses/>.
-***/
-
-#if defined __x86_64__ && defined __ILP32__
-/* The x32 ABI defines all of its syscalls with bit 30 set, which causes
-   issues when attempting to use syscalls as simple indices into an array.
-   Instead, use the syscall id & ~SYSCALL_MASK as the index, and | the
-   internal id with the syscall mask as needed.
-*/
-#include <asm/unistd.h>
-#define SYSCALL_TO_INDEX(x) ((x) & ~__X32_SYSCALL_BIT)
-#define INDEX_TO_SYSCALL(x) ((x) | __X32_SYSCALL_BIT)
-#else
-#define SYSCALL_TO_INDEX(x) (x)
-#define INDEX_TO_SYSCALL(x) (x)
-#endif
-
-const char *syscall_to_name(int id);
-int syscall_from_name(const char *name);
-
-int syscall_max(void);
diff --git a/src/test/test-tables.c b/src/test/test-tables.c
index 3b7800c..dff6431 100644
--- a/src/test/test-tables.c
+++ b/src/test/test-tables.c
@@ -43,7 +43,6 @@
 #include "unit-name.h"
 #include "unit.h"
 #include "util.h"
-#include "syscall-list.h"
 
 #include "test-tables.h"
 
@@ -99,7 +98,5 @@ int main(int argc, char **argv) {
         test_table(unit_load_state, UNIT_LOAD_STATE);
         test_table(unit_type, UNIT_TYPE);
 
-        _test_table("syscall", syscall_to_name, syscall_from_name, syscall_max(), true);
-
         return EXIT_SUCCESS;
 }
-- 
1.8.5.4



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