mirror of
https://github.com/systemd/systemd.git
synced 2025-01-11 09:18:07 +03:00
nspawn: split out seccomp call into nspawn-seccomp.[ch]
Split seccomp into nspawn-seccomp.[ch]. Currently there are no changes, but this will make it easy in the future to share or use the seccomp logic from systemd core.
This commit is contained in:
parent
231bfb1b02
commit
f011b0b87a
@ -3016,6 +3016,8 @@ systemd_nspawn_SOURCES = \
|
|||||||
src/nspawn/nspawn-expose-ports.h \
|
src/nspawn/nspawn-expose-ports.h \
|
||||||
src/nspawn/nspawn-cgroup.c \
|
src/nspawn/nspawn-cgroup.c \
|
||||||
src/nspawn/nspawn-cgroup.h \
|
src/nspawn/nspawn-cgroup.h \
|
||||||
|
src/nspawn/nspawn-seccomp.c \
|
||||||
|
src/nspawn/nspawn-seccomp.h \
|
||||||
src/nspawn/nspawn-register.c \
|
src/nspawn/nspawn-register.c \
|
||||||
src/nspawn/nspawn-register.h \
|
src/nspawn/nspawn-register.h \
|
||||||
src/nspawn/nspawn-setuid.c \
|
src/nspawn/nspawn-setuid.c \
|
||||||
|
143
src/nspawn/nspawn-seccomp.c
Normal file
143
src/nspawn/nspawn-seccomp.c
Normal file
@ -0,0 +1,143 @@
|
|||||||
|
/***
|
||||||
|
This file is part of systemd.
|
||||||
|
|
||||||
|
Copyright 2016 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 <errno.h>
|
||||||
|
#include <linux/netlink.h>
|
||||||
|
#include <sys/capability.h>
|
||||||
|
#include <sys/types.h>
|
||||||
|
|
||||||
|
#ifdef HAVE_SECCOMP
|
||||||
|
#include <seccomp.h>
|
||||||
|
#endif
|
||||||
|
|
||||||
|
#include "log.h"
|
||||||
|
|
||||||
|
#ifdef HAVE_SECCOMP
|
||||||
|
#include "seccomp-util.h"
|
||||||
|
#endif
|
||||||
|
|
||||||
|
#include "nspawn-seccomp.h"
|
||||||
|
|
||||||
|
#ifdef HAVE_SECCOMP
|
||||||
|
|
||||||
|
static int seccomp_add_default_syscall_filter(scmp_filter_ctx ctx,
|
||||||
|
uint64_t cap_list_retain) {
|
||||||
|
unsigned i;
|
||||||
|
int r;
|
||||||
|
static const struct {
|
||||||
|
uint64_t capability;
|
||||||
|
int syscall_num;
|
||||||
|
} blacklist[] = {
|
||||||
|
{ CAP_SYS_RAWIO, SCMP_SYS(iopl) },
|
||||||
|
{ CAP_SYS_RAWIO, SCMP_SYS(ioperm) },
|
||||||
|
{ CAP_SYS_BOOT, SCMP_SYS(kexec_load) },
|
||||||
|
{ CAP_SYS_ADMIN, SCMP_SYS(swapon) },
|
||||||
|
{ CAP_SYS_ADMIN, SCMP_SYS(swapoff) },
|
||||||
|
{ CAP_SYS_ADMIN, SCMP_SYS(open_by_handle_at) },
|
||||||
|
{ CAP_SYS_MODULE, SCMP_SYS(init_module) },
|
||||||
|
{ CAP_SYS_MODULE, SCMP_SYS(finit_module) },
|
||||||
|
{ CAP_SYS_MODULE, SCMP_SYS(delete_module) },
|
||||||
|
{ CAP_SYSLOG, SCMP_SYS(syslog) },
|
||||||
|
};
|
||||||
|
|
||||||
|
for (i = 0; i < ELEMENTSOF(blacklist); i++) {
|
||||||
|
if (cap_list_retain & (1ULL << blacklist[i].capability))
|
||||||
|
continue;
|
||||||
|
|
||||||
|
r = seccomp_rule_add(ctx, SCMP_ACT_ERRNO(EPERM), blacklist[i].syscall_num, 0);
|
||||||
|
if (r == -EFAULT)
|
||||||
|
continue; /* unknown syscall */
|
||||||
|
if (r < 0) {
|
||||||
|
log_error_errno(r, "Failed to block syscall: %m");
|
||||||
|
return r;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
int setup_seccomp(uint64_t cap_list_retain) {
|
||||||
|
scmp_filter_ctx seccomp;
|
||||||
|
int r;
|
||||||
|
|
||||||
|
seccomp = seccomp_init(SCMP_ACT_ALLOW);
|
||||||
|
if (!seccomp)
|
||||||
|
return log_oom();
|
||||||
|
|
||||||
|
r = seccomp_add_secondary_archs(seccomp);
|
||||||
|
if (r < 0) {
|
||||||
|
log_error_errno(r, "Failed to add secondary archs to seccomp filter: %m");
|
||||||
|
goto finish;
|
||||||
|
}
|
||||||
|
|
||||||
|
r = seccomp_add_default_syscall_filter(seccomp, cap_list_retain);
|
||||||
|
if (r < 0)
|
||||||
|
goto finish;
|
||||||
|
|
||||||
|
/*
|
||||||
|
Audit is broken in containers, much of the userspace audit
|
||||||
|
hookup will fail if running inside a container. We don't
|
||||||
|
care and just turn off creation of audit sockets.
|
||||||
|
|
||||||
|
This will make socket(AF_NETLINK, *, NETLINK_AUDIT) fail
|
||||||
|
with EAFNOSUPPORT which audit userspace uses as indication
|
||||||
|
that audit is disabled in the kernel.
|
||||||
|
*/
|
||||||
|
|
||||||
|
r = seccomp_rule_add(
|
||||||
|
seccomp,
|
||||||
|
SCMP_ACT_ERRNO(EAFNOSUPPORT),
|
||||||
|
SCMP_SYS(socket),
|
||||||
|
2,
|
||||||
|
SCMP_A0(SCMP_CMP_EQ, AF_NETLINK),
|
||||||
|
SCMP_A2(SCMP_CMP_EQ, NETLINK_AUDIT));
|
||||||
|
if (r < 0) {
|
||||||
|
log_error_errno(r, "Failed to add audit seccomp rule: %m");
|
||||||
|
goto finish;
|
||||||
|
}
|
||||||
|
|
||||||
|
r = seccomp_attr_set(seccomp, SCMP_FLTATR_CTL_NNP, 0);
|
||||||
|
if (r < 0) {
|
||||||
|
log_error_errno(r, "Failed to unset NO_NEW_PRIVS: %m");
|
||||||
|
goto finish;
|
||||||
|
}
|
||||||
|
|
||||||
|
r = seccomp_load(seccomp);
|
||||||
|
if (r == -EINVAL) {
|
||||||
|
log_debug_errno(r, "Kernel is probably not configured with CONFIG_SECCOMP. Disabling seccomp audit filter: %m");
|
||||||
|
r = 0;
|
||||||
|
goto finish;
|
||||||
|
}
|
||||||
|
if (r < 0) {
|
||||||
|
log_error_errno(r, "Failed to install seccomp audit filter: %m");
|
||||||
|
goto finish;
|
||||||
|
}
|
||||||
|
|
||||||
|
finish:
|
||||||
|
seccomp_release(seccomp);
|
||||||
|
return r;
|
||||||
|
}
|
||||||
|
|
||||||
|
#else
|
||||||
|
|
||||||
|
int setup_seccomp(uint64_t cap_list_retain) {
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
#endif
|
24
src/nspawn/nspawn-seccomp.h
Normal file
24
src/nspawn/nspawn-seccomp.h
Normal file
@ -0,0 +1,24 @@
|
|||||||
|
#pragma once
|
||||||
|
|
||||||
|
/***
|
||||||
|
This file is part of systemd.
|
||||||
|
|
||||||
|
Copyright 2016 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/types.h>
|
||||||
|
|
||||||
|
int setup_seccomp(uint64_t cap_list_retain);
|
@ -26,9 +26,6 @@
|
|||||||
#include <linux/loop.h>
|
#include <linux/loop.h>
|
||||||
#include <pwd.h>
|
#include <pwd.h>
|
||||||
#include <sched.h>
|
#include <sched.h>
|
||||||
#ifdef HAVE_SECCOMP
|
|
||||||
#include <seccomp.h>
|
|
||||||
#endif
|
|
||||||
#ifdef HAVE_SELINUX
|
#ifdef HAVE_SELINUX
|
||||||
#include <selinux/selinux.h>
|
#include <selinux/selinux.h>
|
||||||
#endif
|
#endif
|
||||||
@ -82,15 +79,13 @@
|
|||||||
#include "nspawn-settings.h"
|
#include "nspawn-settings.h"
|
||||||
#include "nspawn-setuid.h"
|
#include "nspawn-setuid.h"
|
||||||
#include "nspawn-stub-pid1.h"
|
#include "nspawn-stub-pid1.h"
|
||||||
|
#include "nspawn-seccomp.h"
|
||||||
#include "parse-util.h"
|
#include "parse-util.h"
|
||||||
#include "path-util.h"
|
#include "path-util.h"
|
||||||
#include "process-util.h"
|
#include "process-util.h"
|
||||||
#include "ptyfwd.h"
|
#include "ptyfwd.h"
|
||||||
#include "random-util.h"
|
#include "random-util.h"
|
||||||
#include "rm-rf.h"
|
#include "rm-rf.h"
|
||||||
#ifdef HAVE_SECCOMP
|
|
||||||
#include "seccomp-util.h"
|
|
||||||
#endif
|
|
||||||
#include "selinux-util.h"
|
#include "selinux-util.h"
|
||||||
#include "signal-util.h"
|
#include "signal-util.h"
|
||||||
#include "socket-util.h"
|
#include "socket-util.h"
|
||||||
@ -1667,99 +1662,6 @@ static int reset_audit_loginuid(void) {
|
|||||||
return 0;
|
return 0;
|
||||||
}
|
}
|
||||||
|
|
||||||
static int setup_seccomp(void) {
|
|
||||||
|
|
||||||
#ifdef HAVE_SECCOMP
|
|
||||||
static const struct {
|
|
||||||
uint64_t capability;
|
|
||||||
int syscall_num;
|
|
||||||
} blacklist[] = {
|
|
||||||
{ CAP_SYS_RAWIO, SCMP_SYS(iopl) },
|
|
||||||
{ CAP_SYS_RAWIO, SCMP_SYS(ioperm) },
|
|
||||||
{ CAP_SYS_BOOT, SCMP_SYS(kexec_load) },
|
|
||||||
{ CAP_SYS_ADMIN, SCMP_SYS(swapon) },
|
|
||||||
{ CAP_SYS_ADMIN, SCMP_SYS(swapoff) },
|
|
||||||
{ CAP_SYS_ADMIN, SCMP_SYS(open_by_handle_at) },
|
|
||||||
{ CAP_SYS_MODULE, SCMP_SYS(init_module) },
|
|
||||||
{ CAP_SYS_MODULE, SCMP_SYS(finit_module) },
|
|
||||||
{ CAP_SYS_MODULE, SCMP_SYS(delete_module) },
|
|
||||||
{ CAP_SYSLOG, SCMP_SYS(syslog) },
|
|
||||||
};
|
|
||||||
|
|
||||||
scmp_filter_ctx seccomp;
|
|
||||||
unsigned i;
|
|
||||||
int r;
|
|
||||||
|
|
||||||
seccomp = seccomp_init(SCMP_ACT_ALLOW);
|
|
||||||
if (!seccomp)
|
|
||||||
return log_oom();
|
|
||||||
|
|
||||||
r = seccomp_add_secondary_archs(seccomp);
|
|
||||||
if (r < 0) {
|
|
||||||
log_error_errno(r, "Failed to add secondary archs to seccomp filter: %m");
|
|
||||||
goto finish;
|
|
||||||
}
|
|
||||||
|
|
||||||
for (i = 0; i < ELEMENTSOF(blacklist); i++) {
|
|
||||||
if (arg_retain & (1ULL << blacklist[i].capability))
|
|
||||||
continue;
|
|
||||||
|
|
||||||
r = seccomp_rule_add(seccomp, SCMP_ACT_ERRNO(EPERM), blacklist[i].syscall_num, 0);
|
|
||||||
if (r == -EFAULT)
|
|
||||||
continue; /* unknown syscall */
|
|
||||||
if (r < 0) {
|
|
||||||
log_error_errno(r, "Failed to block syscall: %m");
|
|
||||||
goto finish;
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
/*
|
|
||||||
Audit is broken in containers, much of the userspace audit
|
|
||||||
hookup will fail if running inside a container. We don't
|
|
||||||
care and just turn off creation of audit sockets.
|
|
||||||
|
|
||||||
This will make socket(AF_NETLINK, *, NETLINK_AUDIT) fail
|
|
||||||
with EAFNOSUPPORT which audit userspace uses as indication
|
|
||||||
that audit is disabled in the kernel.
|
|
||||||
*/
|
|
||||||
|
|
||||||
r = seccomp_rule_add(
|
|
||||||
seccomp,
|
|
||||||
SCMP_ACT_ERRNO(EAFNOSUPPORT),
|
|
||||||
SCMP_SYS(socket),
|
|
||||||
2,
|
|
||||||
SCMP_A0(SCMP_CMP_EQ, AF_NETLINK),
|
|
||||||
SCMP_A2(SCMP_CMP_EQ, NETLINK_AUDIT));
|
|
||||||
if (r < 0) {
|
|
||||||
log_error_errno(r, "Failed to add audit seccomp rule: %m");
|
|
||||||
goto finish;
|
|
||||||
}
|
|
||||||
|
|
||||||
r = seccomp_attr_set(seccomp, SCMP_FLTATR_CTL_NNP, 0);
|
|
||||||
if (r < 0) {
|
|
||||||
log_error_errno(r, "Failed to unset NO_NEW_PRIVS: %m");
|
|
||||||
goto finish;
|
|
||||||
}
|
|
||||||
|
|
||||||
r = seccomp_load(seccomp);
|
|
||||||
if (r == -EINVAL) {
|
|
||||||
log_debug_errno(r, "Kernel is probably not configured with CONFIG_SECCOMP. Disabling seccomp audit filter: %m");
|
|
||||||
r = 0;
|
|
||||||
goto finish;
|
|
||||||
}
|
|
||||||
if (r < 0) {
|
|
||||||
log_error_errno(r, "Failed to install seccomp audit filter: %m");
|
|
||||||
goto finish;
|
|
||||||
}
|
|
||||||
|
|
||||||
finish:
|
|
||||||
seccomp_release(seccomp);
|
|
||||||
return r;
|
|
||||||
#else
|
|
||||||
return 0;
|
|
||||||
#endif
|
|
||||||
|
|
||||||
}
|
|
||||||
|
|
||||||
static int setup_propagate(const char *root) {
|
static int setup_propagate(const char *root) {
|
||||||
const char *p, *q;
|
const char *p, *q;
|
||||||
@ -2988,7 +2890,7 @@ static int outer_child(
|
|||||||
if (r < 0)
|
if (r < 0)
|
||||||
return r;
|
return r;
|
||||||
|
|
||||||
r = setup_seccomp();
|
r = setup_seccomp(arg_retain);
|
||||||
if (r < 0)
|
if (r < 0)
|
||||||
return r;
|
return r;
|
||||||
|
|
||||||
|
Loading…
Reference in New Issue
Block a user