diff options
Diffstat (limited to 'pkg/seccomp/seccomp_unsafe.go')
-rw-r--r-- | pkg/seccomp/seccomp_unsafe.go | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/pkg/seccomp/seccomp_unsafe.go b/pkg/seccomp/seccomp_unsafe.go new file mode 100644 index 000000000..6682f8d9b --- /dev/null +++ b/pkg/seccomp/seccomp_unsafe.go @@ -0,0 +1,49 @@ +// Copyright 2018 Google Inc. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// +build amd64 + +package seccomp + +import ( + "fmt" + "syscall" + "unsafe" + + "gvisor.googlesource.com/gvisor/pkg/abi/linux" +) + +// sockFprog is sock_fprog taken from <linux/filter.h>. +type sockFprog struct { + Len uint16 + pad [6]byte + Filter *linux.BPFInstruction +} + +func seccomp(instrs []linux.BPFInstruction) error { + // SYS_SECCOMP is not available in syscall package. + const SYS_SECCOMP = 317 + + // PR_SET_NO_NEW_PRIVS is required in order to enable seccomp. See seccomp(2) for details. + if _, _, err := syscall.RawSyscall(syscall.SYS_PRCTL, linux.PR_SET_NO_NEW_PRIVS, 1, 0); err != 0 { + return fmt.Errorf("failed to set PR_SET_NO_NEW_PRIVS: %v", err) + } + sockProg := sockFprog{Len: uint16(len(instrs)), Filter: (*linux.BPFInstruction)(unsafe.Pointer(&instrs[0]))} + + // TODO: Use SECCOMP_FILTER_FLAG_KILL_PROCESS when available. + if _, _, err := syscall.RawSyscall(SYS_SECCOMP, linux.SECCOMP_SET_MODE_FILTER, linux.SECCOMP_FILTER_FLAG_TSYNC, uintptr(unsafe.Pointer(&sockProg))); err != 0 { + return fmt.Errorf("failed to set seccomp filter: %v", err) + } + return nil +} |